ARCA biopharma, Inc. (Form: 10-K, Received: 03/27/2009 06:09:02)

Gly Carrier*

Wt/Wt

µ _2c

VF = Very Favorable Genotype F = Favorable Genotype

UF = Unfavorable Genotype

Del Carrier ^†

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

þ	ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2008

¨	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission File Number: 000-22873

ARCA BIOPHARMA, INC.

(Exact Name of Registrant as Specified in Its Charter)


Delaware		36-3855489
(State or Other Jurisdiction of Incorporation or Organization)		(I.R.S. Employer Identification No.)

8001 Arista Place, Suite 200 Broomfield, CO		80021
(Address of Principal Executive Offices)		(Zip Code)

(720) 940-2200

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Exchange Act:


Title of Each Class		Name of Each Exchange on Which Registered
Common Stock $0.001 par value		Nasdaq Global Market

Securities registered pursuant to Section 12(g) of the Exchange Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in rule 405 of the Securities Act. Yes ¨ No þ

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 and Section 15(d) of the Act. Yes ¨ No þ

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes þ No ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. þ

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,” and “small reporting company” in Rule 12b-2 of the Exchange Act.


Large accelerated filer ¨		Accelerated filer ¨
Non-accelerated filer ¨ (Do not check if a smaller reporting company)		Smaller reporting company þ

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ¨ No þ

The aggregate market value of the common stock held by non-affiliates of the Registrant on June 30, 2008, the last business day of the most recently completed second fiscal quarter, was $29,925,354 based on the last sale price of the common stock as reported on that day by the Nasdaq Global Market.

As of March 17, 2009, the Registrant had 7,567,399 shares of common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant’s Definitive Proxy Statement, which will be filed with the Commission pursuant to Section 14A in connection with the 2009 annual meeting of stockholders, are incorporated by reference into Part III of this Form 10-K.

TABLE OF CONTENTS


PART I		3

Item 1. Business		3

Item 1A. Risk Factors		22

Item 1B. Unresolved Staff Comments		47

Item 2. Properties		48

Item 3. Legal Proceedings		48

Item 4. Submission of Matters to a Vote of Security Holders		49

PART II		50

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities		50

Item 6. Selected Financial Data		51

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations		51

Item 7A. Quantitative and Qualitative Disclosures About Market Risk		61

Item 8. Financial Statements and Supplementary Data		62

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM		63

CONSOLIDATED BALANCE SHEETS		64

CONSOLIDATED STATEMENTS OF OPERATIONS		65

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY		66

CONSOLIDATED STATEMENTS OF CASH FLOWS		67

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS		68

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure		89

Item 9A(T). Controls and Procedures		89

Item 9B. Other Information		90

PART III		91

Item 10. Directors, Executive Officers and Corporate Governance		91

Item 11. Executive Compensation		91

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters		91

Item 13. Certain Relationships and Related Transactions, and Director Independence		92

Item 14. Principal Accountant Fees and Services		92

PART IV		93

Item 15. Exhibits and Financial Statement Schedules		93

SIGNATURES		98

PART I

Item 1.

Business

We have included or incorporated by reference into this Annual Report on Form 10-K statements that may constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Forward-looking statements may be identified by words including “anticipate,” “plan,” “believe,” “intend,” “estimate,” “expect,” “should,” “may,” “potential” and similar expressions. Such statements are based on our management’s current expectations and involve risks and uncertainties. Our actual results and performance could differ materially from those projected in the forward-looking statements as a result of many factors discussed in this Annual Report, including those set forth in this Item 1, as well as under “Item 1A. Risk Factors” and “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.” We do not intend to update any of the forward-looking statements after the date of this Annual Report to conform these statements to actual results unless required by law.

Merger Transaction

On January 27 2009, ARCA biopharma, Inc., formerly known as Nuvelo, Inc., or Nuvelo, completed the merger contemplated by that Agreement and Plan of Merger and Reorganization, dated September 24, 2008, as amended October 28, 2008, by and among Nuvelo, Dawn Acquisition Sub, Inc., a wholly-owned subsidiary of Nuvelo, or Merger Sub, and ARCA biopharma, Inc., or ARCA, a privately held developmental-stage biopharmaceutical company based in Broomfield, Colorado, which merger agreement, as amended, is referred to herein as the Merger Agreement.

In accordance with the Merger Agreement, immediately prior to the consummation of the merger, Nuvelo effected a reverse stock split of its common stock. Pursuant to this reverse stock split, each 20 shares of Nuvelo’s common stock that were issued and outstanding immediately prior to the merger were converted into one share of Nuvelo’s common stock. In addition, pursuant to the Merger Agreement, Merger Sub merged with and into ARCA, with ARCA continuing after the merger as the surviving corporation and a wholly owned subsidiary of Nuvelo. Immediately following the merger, Nuvelo changed its name to ARCA biopharma, Inc. On January 28, 2009, ARCA’s common stock began trading on the Nasdaq Global Market under the new symbol “ABIO.”

The business combination is treated as a reverse merger for accounting purposes, and as such, historical financial information included in our future filings with the SEC will be the financial information of ARCA as the accounting acquirer in the merger. However, since the merger was consummated after the end of the period covered by this report, the historical financial information included in this report is that of Nuvelo prior to the merger and not that of ARCA.

Unless the context otherwise requires, all references herein to “ARCA,” “the Company,” “we,” “us” and “our” refer to ARCA both before and after the completion of the merger, and all references to “Nuvelo” refer to Nuvelo and its business prior to the completion of the merger and the name change. All share and per share amounts contained in this report give effect to the reverse stock split completed in connection with the merger.

Nuvelo’s Business Prior to the Merger

Prior to the completion of the merger, Nuvelo was developing drugs for acute cardiovascular disease, gastro-intestinal, or GI, diseases and other debilitating medical conditions. Its development pipeline included NU172, a direct thrombin inhibitor that has completed Phase I development for use as a short-acting anticoagulant during medical or surgical procedures, and Phase I clinical candidate NU206, a recombinant, secreted protein for the potential treatment of GI, diseases, including inflammatory bowel disease, mucositis and bone disease.

On March 17, 2008, Nuvelo announced its decision to discontinue clinical development of its clinical-stage product candidate, alfimeprase, and restructure its operations in order to make additional resources available for its other research and development programs. As part of the restructuring plan, Nuvelo reduced its workforce by approximately 19% and recorded a restructuring expense of $2.5 million, including $1.3 million of termination benefits and $1.2 million of non-cash stock-based compensation expense.

Overview

ARCA is a biopharmaceutical company whose principal focus is developing genetically-targeted therapies for heart failure and other cardiovascular diseases.

ARCA’s lead product candidate is Gencaro ^TM (bucindolol hydrochloride), a pharmacologically unique beta-blocker and mild vasodilator, which is under review by the U.S. Food and Drug Administration, or FDA, for chronic heart failure, or HF. ARCA also plans to pursue several significant follow-on indications for Gencaro. Gencaro is an oral tablet formulation, dosed twice daily. ARCA has identified common genetic variations, or genetic markers, that predict patient response to Gencaro. Subject to approval by the FDA, ARCA, through its collaboration with Laboratory Corporation of America, or LabCorp, anticipates introducing a test for these genetic markers with the market launch of Gencaro, potentially making Gencaro the first genetically-personalized cardiovascular drug. When prescribed using the test for these markers, ARCA believes that Gencaro can become an important new therapy for many chronic heart failure patients, with the potential for positive clinical outcomes in a defined genetic subpopulation, and good tolerability. In September 2008, the FDA formally accepted for filing ARCA’s New Drug Application, or NDA, for Gencaro as a potential treatment for HF. In accordance with the Prescription Drug User Free Act, or PDUFA, the FDA’s goal is to complete its review of the Gencaro NDA by May 31, 2009, and ARCA anticipates an FDA decision on the approvability of Gencaro in the second or third quarter of 2009. Gencaro was the subject of a major North America based heart failure Phase III trial, known as BEST, which ARCA believes will provide the primary basis for approval of Gencaro in the U.S.

Chronic heart failure is one of the largest health care problems in the United States and the rest of the world. Beta-blockers are part of the current standard of care for HF, and are considered to be among the most effective drug classes for the disease. However, a significant percentage of eligible patients in the United States is not being treated, or does not tolerate or respond well to those beta-blockers currently approved for the treatment of HF. ARCA believes that new therapies for which patient response can be predicted before a drug is prescribed can help improve the current standard of practice in the treatment of HF.

ARCA has collaborated with LabCorp to develop the Gencaro Test, a companion test for the genetic markers that predict clinical response to Gencaro. The proposed use of the Gencaro Test, if approved by the FDA, will be to enable a physician to determine, prior to therapy, whether a patient is likely to have a good response to Gencaro. LabCorp has developed the Gencaro Test to be administered using a blood test or a cheek swab, and to provide prompt results to the treating physician. The Gencaro Test was submitted through the Premarket Approval, or PMA, process in January 2009, and an FDA decision on approval, based on FDA guidance, is expected in conjunction with the FDA decision on Gencaro. ARCA intends to closely coordinate the commercial launch of Gencaro and the Gencaro Test with LabCorp.

ARCA holds worldwide rights to Gencaro and plans to commercialize the drug in the U.S. through its own specialized sales force. ARCA’s commercial effort in the United States will focus on cardiologists specializing in heart failure, and selected other physicians. ARCA intends to seek partners to assist it in commercializing Gencaro in international markets. ARCA believes that Gencaro will have market exclusivity under federal and international laws following commercial launch, and will also potentially have protection under patent applications, which ARCA believes would substantially extend market exclusivity. ARCA also plans to pursue several significant follow-on indications for Gencaro, including various forms of cardiac arrhythmias.

ARCA is also evaluating continued development of NU172, a novel, short-acting anticoagulant. ARCA believes that NU172 may have potential as a new therapy in indications where heparin paired with its antidote,

protamine, is the current standard of care, such as coronary artery bypass graft (CABG) surgery, kidney dialysis and a variety of vascular surgical and coronary interventions. NU172 recently completed a successful Phase Ib study. ARCA is currently exploring collaborations for the other research and development programs that Nuvelo had conducted prior to the merger.

ARCA believes that its expertise in cardiovascular pathophysiology and genetics, and its clinical and commercial experience, will enable it to identify and develop other cardiovascular therapies, with an emphasis on those that may be personalized using genetic markers. ARCA is currently exploring such opportunities.

Market Opportunity

HF is one of the world’s most significant health care challenges. Industry sources estimate that about 6 million Americans have HF and nearly 550,000 new patients are diagnosed annually. In addition, HF is the underlying reason for approximately 12 to 15 million annual visits to physicians, 6.5 million annual hospital days and over $34 billion in direct and indirect healthcare costs. Some sources estimate that the number of chronic heart failure patients in countries within the European Union is significantly higher than in the U.S.

Medical therapy has made progress in treating HF, but morbidity and mortality remain high. The current standard of care for HF involves the use of various therapies that operate to inhibit the activity of the renin-angiotensin-aldosterone system (these include angiotensin converting enzyme, or ACE, inhibitors, angiotensin II receptor blockers, or ARB’s, and aldosterone receptor antagonists), diuretics, and drugs in the class known as beta-blockers.

Beta-blockers are named for their characteristic mechanism of binding to certain receptors in the nervous system of the heart, and in doing so blocking those receptors from being activated by binding with other molecules. This drug class is part of the current standard of care in patients with HF and left ventricular dysfunction. The American Heart Association and the American College of Cardiology physician guidelines for the treatment of HF state the following:

Beta-blockers should be prescribed to all patients with stable heart failure due to reduced left ventricular ejection fraction, unless they have a contraindication to their use or have been shown to be unable to tolerate treatment with the drugs. Because of favorable effects of beta-blockers on survival and disease progression, treatment with a beta-blocker should be initiated as soon as left ventricular dysfunction is diagnosed.

The benefits of beta-blockade are well established. Beta blockers are potentially usable by a majority of the HF population, they are effective in reducing mortality, and they are considered to be the most effective drugs overall for the treatment of HF. However, many patients who could potentially benefit from therapy are not being treated. It is estimated that approximately 40% of eligible HF patients in the U.S., and 50% in the European Union, are not being treated with beta-blockers. Further, it is believed that a substantial portion of patients being treated with beta-blockers are not receiving the target dose. Based on analysis of this market and expert opinion, ARCA believes this lack of adoption may be due in part to the fact that a significant percentage of chronic heart failure patients do not tolerate one or more of the beta-blockers currently approved for HF, or do not respond well to them.

In addition, due to the fact that patients respond unevenly to beta-blockers, it is difficult to predict what a particular patient’s response is likely to be in advance of therapy. This uncertainty creates special problems in the context of HF. The current standard of practice in administering a beta-blocker for HF involves a lengthy, often months-long process, in which the patient is gradually moved from a low initial dose up to one that has been proven to be clinically beneficial. This extended protocol is necessary because the therapeutic mechanism of this drug class inhibits processes in the failing heart that, while deleterious over the long term, initially provide support for diminished cardiac function. Thus, the dosage must be increased slowly to allow the patient to adjust to the therapy, and it may be months before it is known whether the patient will both tolerate the therapy and will benefit from it.

During this process, the patient may feel worse and exhibit no objective benefit. However, it can be difficult for the physician to determine whether this is due to the mechanism of the drug class, or whether it is a problem with the particular drug. A serious adverse event, such as hospitalization for an acute episode, or death, may be the first substantial evidence that the patient is not responding well to the particular therapy. ARCA believes that many HF patients on beta-blockers never reach their target dose, whether due to actual side effects or the perception that the patient is not benefiting. Some patients simply do not respond, after enduring this long and potentially difficult process. Unfortunately, the physician has no good method to determine, in advance of therapy, whether a patient is likely to benefit, introducing an element of trial and error into the use of these agents that is frustrating to prescribers, potentially harmful to patients and costly to payors. ARCA believes that a new HF therapy that includes a simple test to identify those patients likely to benefit, can help alleviate some of the problems encountered with the current standard of practice.

ARCA Strategy

ARCA’s mission is to become a leading biopharmaceutical company developing and commercializing cardiovascular therapies, with an emphasis on genetically-targeted therapies. To achieve this goal, ARCA is pursuing the following strategies:

•

Obtain FDA approval for Gencaro for the treatment of chronic heart failure and initiate U.S. commercialization. ARCA believes that Gencaro has a clinical record that supports its approvability. Gencaro’s NDA was accepted for filing by the FDA in September 2008. ARCA expects a decision by the FDA on the approvability of Gencaro in the second or third quarter of 2009. If Gencaro is approved, ARCA currently intends to market it in the United States as the first pharmacogenetic cardiovascular therapy through its own sales force. ARCA plans to differentiate Gencaro based on its pharmacogenetic profile, unique mode of action, the Gencaro Test’s expected ability to predict response, favorable tolerability and improved clinical endpoints. ARCA plans to support its commercialization effort with a publication strategy, appropriate contacts with key opinion leaders, a heart failure patient registry and an effective reimbursement strategy, in compliance with applicable federal requirements.

•

Build a specialty sales and marketing capability. In anticipation of the potential commercial launch of Gencaro in the U.S., ARCA is building a specialty sales and marketing organization, focusing on cardiologists that specialize in heart failure, and other physicians who treat heart failure or are influential in this setting. ARCA’s management and employees, including its chief executive officer and its executive vice president in charge of commercialization, have extensive experience in the commercialization of cardiovascular therapies, including specialty sales and marketing organizations. ARCA also intends to use this sales and marketing organization to commercialize future product candidates in the U.S.

•

Expand Gencaro indications. ARCA plans to pursue clinical development of several potential additional indications for Gencaro, including the prevention of several forms of arrhythmia. ARCA believes these indications have pharmacogenetic potential, reasonable clinical development paths, will help differentiate Gencaro, and could potentially be successfully marketed by the specialty sales and marketing organization ARCA is currently building.

•

Develop NU172. ARCA’s second investigational compound under consideration is NU172, a novel, short-acting anticoagulant that ARCA is evaluating for development as a potential new therapy in indications where heparin paired with its antidote, protamine, are the current standard of care, such as CABG surgery, kidney dialysis and a variety of vascular surgical and coronary interventions. NU172 recently completed a successful Phase Ib study.

•

Build a cardiovascular pipeline. ARCA’s management and employees, including its chief executive officer and chief science and medical officer, have extensive experience in cardiovascular research, molecular genetics, cardiovascular clinical development, and the commercialization of cardiovascular

therapies. ARCA intends to leverage this expertise to seek to identify, acquire, develop and commercialize other cardiovascular products or candidates, with an emphasis on pharmacogenetic applications.

Gencaro

Gencaro (bucindolol hydrochloride) is a pharmacologically unique beta-blocker and mild vasodilator which is under review by the FDA for the treatment of chronic heart failure. ARCA also plans to pursue several significant follow-on indications for Gencaro. Gencaro is considered part of the beta-blocker class because of its property of blocking both beta-1, or ß ₁ and beta-2, or ß ₂ receptors in the cardiac nervous system from binding with other molecules that activate these receptors. Because of its mild vasodilator effects, Gencaro is well-tolerated in patients with advanced HF. Originally developed by Bristol-Myers Squibb, or BMS, the active pharmaceutical ingredient, or API, in Gencaro, bucindolol has been tested clinically in approximately 4,500 patients. Gencaro was the subject of a Phase III heart failure mortality trial of over 2,700, mostly U.S. patients, known as the “BEST” trial. The BEST trial included a DNA bank of over 1,000 patients, which was used to conduct studies of the effect of genetic variation on bucindolol response.

At the time of the BEST trial, ARCA’s founding scientists, Dr. Michael Bristow and Dr. Stephen Liggett, hypothesized that the unique pharmacologic properties of Gencaro would interact with common genetic variations or polymorphisms of the ß ₁ , and alpha2C, or µ _2C , receptors, which are important receptors that regulate cardiac function. They tested this hypothesis prospectively in a substudy conducted using data from the BEST DNA bank. On the basis of this study, Drs. Bristow and Liggett determined that patients with certain variations, or polymorphisms, in these receptors had substantially improved outcomes on primary and certain secondary clinical endpoints in the trial, such as mortality, heart failure progression and hospitalization, relative to the general patient population of the BEST trial. ARCA believes that these polymorphisms, which are detectable using standard genetic testing technology, can serve as diagnostic markers for predicting enhanced therapeutic response to Gencaro, and avoiding adverse events, in individual patients.

Pharmacology and Pharmacogenetics

Gencaro’s pharmacology appears to be different from other compounds in the beta-blocker class in two fundamental respects. First, studies conducted by ARCA researchers indicate that in human myocardial preparations, Gencaro significantly inactivates high functioning ß ₁ receptors through a mechanism separate from ß ₁ -blockade, in addition to inhibiting the binding activity of the ß ₁ receptor like a typical beta-blocker. Second, these same ARCA studies indicate that Gencaro lowers the systemic levels of the neurotransmitter norepinephrine, or NE, which is released by cardiac and other sympathetic nerves. These two properties interact with common genetic variations in two cardiac receptors, the ß ₁ and µ _2C receptors, to produce the unique pharmacogenetic profile of Gencaro. ARCA believes that these two properties, and their pharmacogenetic implications, are unique to Gencaro. These receptors, their genetic variants, and the biological system in which they function, are illustrated below:

LOGO

Gencaro has an important interaction with the ß ₁ receptor found on muscle cells, or cardiac myocytes, of the heart. The general role of the ß ₁ receptor and its downstream signaling cascades is to regulate the strength and rate of the heart’s contractions. NE serves as an activator of the ß ₁ receptor, causing the receptor to initiate signaling to the cardiac myocyte. Although this signaling may be beneficial to the failing heart in the short term, in chronic heart failure patients the ß ₁ receptor also initiates harmful, or cardiomyopathic, signaling which, over time, exacerbates the heart’s functional and structural decline. Beta-blockers counteract this destructive process by reducing ß ₁ receptor signaling. They do this by binding to the receptor and blocking NE molecules from binding and activating the signaling activity, and in Gencaro’s case by also inactivating the constitutively active (active in the absence of NE stimulation) state of certain ß ₁ receptors.

There are two common genetic variations of the ß ₁ receptor, each of which ARCA estimates is present in approximately 50% of the U.S. population. One of these variations is known as the “ß ₁ -Arg/Arg” variant. Laboratory studies indicate that this variation results in a higher functioning ß ₁ receptor, one which has a greater ability to mediate the stimulatory effects of NE. In addition, this variation is also more likely to be constitutively active and signal the cardiac myocyte to contract in the absence of NE. Heart failure patients with this genotype may have the potential for greater cardiomyopathic ß ₁ signaling. The other variation, the “ß ₁ -Gly carrier”, also present in about 50% of the U.S. population, results in a ß ₁ receptor that is much lower functioning and, according to laboratory studies, has less probability of being in a constitutively active state compared to the ß ₁ -Arg/Arg receptor.

Gencaro has a powerful interaction with the higher-functioning ß ₁ -Arg/Arg variation of the ß ₁ receptor. Laboratory studies show that constitutively active receptors will continue to signal in the presence of standard beta-blockade. Laboratory studies in isolated human heart preparations also show that Gencaro has the unusual

ability of being able to stop the signaling of constitutively active receptors. ARCA believes that individuals with the ß ₁ -Arg/Arg genotype potentially will recognize an enhanced therapeutic response to Gencaro because of the greater potential for active state, cardiomyopathic signaling among individuals with this genotype, and the larger reduction in signaling that these individuals experience when taking Gencaro, relative to individuals with the ß ₁ -Gly carrier genotype.

The other receptor that appears to give Gencaro its pharmacogenetic properties is the µ _2C receptor. This receptor is located on the terminus of the sympathetic cardiac nerve, at its junction with the cardiac myocyte. The role of this receptor is to modulate the amount of NE that is present at this junction, which in turn affects the activation of ß ₁ receptors and the heart’s activity. There are two important genetic variations of this receptor that appear to affect the performance of Gencaro. Approximately 10-13% of the general population in the U.S. has a modified µ _2C receptor resulting from at least one modified gene that functions poorly. Patients with this variant, also known as the “deletion variant”, or “ µ _2C 322—325 DEL,” are believed to have a diminished ability to regulate the amount of NE released by the cardiac nerve. The remaining 85% of the population has a normal functioning version of this receptor, referred to as the “ µ _2C -wild type.”

Individuals with the deletion variant of the µ _2C receptor tend to have abnormally high levels of NE in their cardiac nervous system. Gencaro, unlike other ß-blocking agents, exhibits the pharmacologic property of “sympatholysis”, or the ability to lower systemic NE levels, through effects that are mediated at least in part by blockade of ß ₂ receptors residing on sympathetic nerve terminals. Therefore, when chronic heart failure patients with the deletion variant of the µ _2C receptor are treated with Gencaro, some of them may be more likely to experience an exaggerated lowering of NE resulting from Gencaro interacting with this variant, leading to a loss of efficacy. This risk may be more pronounced with late stage chronic heart failure patients, who are more dependent on high NE levels to support cardiac function. In contrast to those with the µ _2C deletion variant, the majority of patients with the µ _2C -wild type variant appear to experience only a mild reduction in NE levels from Gencaro. In these patients, mild NE lowering by Gencaro appears to have a favorable therapeutic effect. In addition, patients with the ß ₁ -Arg/Arg genotype can tolerate the greater amount of NE lowering associated with µ _2C DEL genotypes, and in these patients any amount of sympatholysis appears to be beneficial.

The DNA substudy of patients from the BEST trial conducted by Drs. Bristow and Liggett indicated that the combinations of these polymorphisms in individual patients appear to influence the response to Gencaro with respect to significant clinical endpoints. As a result, ARCA anticipates three broad treatment groups for Gencaro:

•

The “very favorable” group, constituting an estimated 47-50% of the U.S. population and comprised of patients with the ß ₁ -Arg/Arg genotype. ARCA believes these individuals may have an enhanced therapeutic response to Gencaro because of its effect on this higher-functioning/constitutively active ß ₁ receptor variant, and a favorable response to NE lowering, regardless of their µ _2C receptor genotype and the degree of bucindolol-associated sympatholysis.

•

A second “favorable” group, constituting an estimated 40% of the U.S. population, and comprised of individuals with the ß ₁ -Gly carrier ß ₁ receptor and wild-type µ _2c receptor. ARCA believes these individuals will benefit therapeutically from Gencaro (although not as much as the very favorable group), because of Gencaro’s enhanced efficacy in the wild-type µ _2C receptor population, combined with some (although reduced) efficacy in ß ₁ -Gly carriers.

•

A third and much smaller, “unfavorable” group, constituting about 10-13% of the U.S. population, comprised of individuals with both ß ₁ -Gly carrier ß ₁ receptors and the deletion variant µ _2C receptors. In these patients, compensatory support to the failing heart may be compromised when Gencaro is administered, likely due to the inability of the lower functioning ß ₁ -Gly carrier ß ₁ receptor to compensate for marked NE lowering from the deletion variant µ _2C receptor. Clinical data suggest Gencaro should not be administered to these patients.

Diagram of subgroups based on ß ₁ - and µ _2c -AR genotype status:

*	ß ₁ 389 Arg/Gly or Gly/Gly

^†	µ _2c 322-325 Wt/Del or Del/Del

The BEST Trial

Bucindolol was originally developed by BMS for hypertension, and was licensed in the early 1990’s to Intercardia, a biopharmaceutical company. Around the time of completion of the Phase II clinical trials with bucindolol, a group of leading heart failure researchers proposed to the U.S. Department of Veteran Affairs Cooperative Clinical Studies Program that a large mortality study of beta-blockers be conducted in chronic heart failure. This grant application was approved, and shortly thereafter the U.S. National Heart, Lung and Blood Institute agreed to join in the sponsorship of the trial, known as the Beta-Blocker Evaluation of Survival Trial, or BEST. The Steering Committee of the BEST trial selected bucindolol as the agent to be tested against placebo, and Intercardia joined the trial as a sponsor.

The BEST trial was a double-blind, placebo-controlled, multi-center study of bucindolol on mortality and morbidity in an advanced chronic heart failure population. Most of the patients were from the United States. The basis for the selection of bucindolol as the tested ß-blocker included its Phase II clinical results and its high tolerability in more advanced HF patients. The trial was planned to run four and one-half years, and enroll 2,800 patients. Under the umbrella of the BEST trial substudies program, a DNA bank and substudy was created, and 1,040 of the BEST patients participated by providing blood for DNA analysis. The DNA bank provided data for the DNA substudy of BEST patients conducted by Drs. Bristow and Liggett.

The BEST trial began in 1995 and enrolled a total of 2,708 chronic heart failure patients. The patients were the most advanced clinical heart failure population ever studied in a large mortality trial, based on baseline systolic blood pressure and other criteria, and clinical stability was not an entry criterion for the trial. The primary endpoint of the BEST trial was total mortality and the pre-specified main secondary endpoint was progression of heart failure, defined as heart failure death, cardiac transplant, heart failure hospitalization, or emergency room visit for the treatment of worsening heart failure not requiring hospitalization. Other pre-specified secondary endpoints included death from cardiovascular causes, a composite of death or heart transplantation, heart failure hospitalization, improvement in left ventricular ejection fraction, incidence of myocardial infarction, quality of life, and any change in the need for concomitant heart failure therapy, including administration of intravenous inotropic agents, intravenous diuretics, or increase in doses of orally-administered diuretics.

In 1999, the BEST trial was terminated prior to the completion of follow-up, in response to a recommendation of the BEST trial Data and Safety Monitoring Board. The primary reason for termination was loss of investigator equipoise; in other words, the fact that the BEST investigators were no longer uncertain regarding the comparative therapeutic merits of giving a placebo versus giving a beta-blocker to a HF patient. Positive mortality results from two other heart failure trials involving other beta-blockers had been reported, and a substantial number of BEST trial investigators concluded that it was unethical to continue to give placebo to

BEST trial participants. As a result, some investigators began to prescribe these other beta-blockers to patients in the trial, which threatened to destroy the trial’s integrity. At the time the BEST study was terminated, approximately 70% of the trial information was available, with 2,708 of a projected 2,800 patients enrolled and 797 out of 916 deaths reported. A companion trial to the BEST trial, known as the BEAT trial, studying European patients with left ventricular dysfunction and a history of heart attack, was terminated when BEST was terminated, with approximately 10% of trial information available (including 343 of 2,000 patients enrolled and 53 out of 630 deaths reported).

Following termination, the preliminary results of both studies were analyzed and published. The preliminary determination and general perception were that the BEST trial had failed, on the basis of not meeting its primary endpoint of total mortality. The published values were a 10% risk reduction in mortality with a p-value of 0.10.

Clinical Results and the DNA Substudy

In 2003 and 2004, the results of the DNA substudy conducted by Drs. Bristow and Liggett began to be released and analyzed. The DNA substudy results indicated a significant enhancement of response on the major clinical endpoints from the BEST trial in patients with the “very favorable” genotype. The risk reduction on clinical efficacy endpoints such as mortality and hospitalization ranged from approximately 35% to approximately 48% in this genotype. In addition, in arrhythmia endpoints of atrial fibrillation or ventricular fibrillation tracked by safety analyses, the risk reduction by bucindolol in the “very favorable” genotype appeared to be even greater, by 62-70%. Also, beginning in 2005, ARCA began to more fully analyze the overall BEST results in accordance with FDA-approved, pre-specified statistical plans, which had not been done by the sponsors when the BEST trial was terminated. For example, as re-analyzed by ARCA in accordance with the statistical plan, there appeared to be a 13% risk reduction on the primary endpoint in the BEST trial of mortality for the entire patient population taking bucindolol, with a p-value of 0.053. In addition, the pre-specified main secondary endpoint, reduction in the progression of heart failure, had not been analyzed when the BEST trial ended. As analyzed by ARCA, the results of the BEST trial indicated a 20% risk reduction on this secondary endpoint for the entire patient population taking bucindolol, that was highly statistically significant (p = 0.00003). The endpoint of heart failure progression, in similar forms, was the original basis of approval for the two beta-blockers currently approved in the U.S. for HF.

Shown below are certain of the primary and secondary endpoint data from the BEST DNA substudy results, by genotype:

BEST Clinical Responses ¹ by Genotype Groups



Endpoint (% of study population)	Very Favorable patients (47%)	Favorable patients (40%)	Unfavorable patients (13%)

All Cause Mortality (ACM), TTE	i 38%*	i 25%	h 4%

Cardiovascular Mortality (CVM), TTE	i 48%*	i 40%*	h 11%

ACM + transplantation	i 43%*	i 24%	h 4%

Heart failure (HF) Morbidity & Mortality, CRF, TTE	i 34%**	i 20%	i 1%

HF M&M, TTE (Adj.)	i 42%**	i 27%	i 16%

HF Hosp days/patient	i 48%**	i 17%	h 19%

AF prevention (from AE db)	i 62%*	i 11%	i 4%

VT/VF prevention (from AE db)	i 70%**	i 44%	i 9%

1	Covariate adjusted, transplant censored analysis

*	p<0.05; **p £ 0.007; TTE: Time To Event; CRF: Case Report Form; Adj.: Adjudicated

While the results of the DNA substudy of the BEST trial indicate that Gencaro’s efficacy varies by genotype with the most robust clinical effects found in patients with the very favorable genotype, they also indicate that patients with the favorable genotype may also benefit from the drug. The results of the DNA substudy indicate that patients in the unfavorable genotype group are not recommended for Gencaro. ARCA estimates that approximately 10-13% of the U.S. HF patient population falls into the unfavorable genotype group. In addition to these results, there was a 45-47% reduction in myocardial infarction in all patients in the BEST trial taking bucindolol. This result, which is unique to Gencaro, was supported by the limited results of the companion BEAT trial in Europe, in which Gencaro, with only approximately 10% of the trial information available, demonstrated a statistically significant improvement in combined myocardial infarction endpoints versus placebo, in patients with left ventricular dysfunction and a history of myocardial infarction.

Regulatory Strategy

In 2005, ARCA approached the FDA to discuss the results of the DNA substudy and ARCA’s revised analysis of data from the BEST trial, as well as the prospect of an NDA for Gencaro for the treatment of HF. Through a number of meetings over the next several years, ARCA received guidance from the FDA on the potential NDA and the coordination of the NDA with a potential application for approval of the Gencaro Test.

The regulatory strategy for Gencaro and the Gencaro Test has been guided by this interaction with the FDA. In the NDA submitted for Gencaro, it is ARCA’s position that Gencaro is approvable based on the full clinical program associated with its development, including data from the total patient cohort population in the BEST trial. The Gencaro clinical development program encompassed numerous clinical studies, including four randomized and placebo controlled studies in patients with HF or myocardial infarction, of which two, the BEST and BEAT trials, evaluated rigorous clinical endpoints, including mortality, hospitalization and myocardial infarction. The remaining clinical studies include the Phase II study conducted by BMS for the treatment of hypertension, several safety studies in other patient populations and a Phase I program in healthy subjects. The NDA presents the pharmacogenetic data from the DNA substudy conducted by Drs. Bristow and Liggett as important to the prescribing information in the proposed label for Gencaro, but not as the basis for its approval.

ARCA believes that the clinical trial results for Gencaro, including the results of the BEST trial and DNA substudy, demonstrate the efficacy and safety of Gencaro for treatment of patients with HF, both for decreasing the risk of mortality and cardiovascular or heart failure hospitalization, and also for reducing the risk of ischemic events and myocardial infarction. The primary endpoint of mortality (when analyzed in accordance with the pre-specified plan) was reduced in all BEST trial patients on bucindolol by 13%, with a p-value of 0.053. While the FDA typically views significance as a p-value of less than 0.05, the Gencaro p-value is within the range found sufficient for approval based on certain FDA precedent. This primary endpoint result is enhanced by the response of the BEST trial patient population with respect to eight secondary endpoints, all of which were positive and statistically significant. As pre-specified with FDA, heart failure progression was the most important secondary endpoint, and was positive and statistically significant; a heart failure progression endpoint was FDA’s basis of approval for the two beta-blockers approved for HF. ARCA also believes that other statistical analyses and the attributes of the BEST trial itself add to its credibility.

ARCA believes Gencaro’s status as a beta-blocker adds further support to its clinical record, as this class has a well-established record of safety and efficacy. The results of the BEST trial are supported by qualitatively consistent results from almost every trial in the beta-blocker class for the treatment of HF. ARCA believes the use of “class effects” to support marketing approval of Gencaro by the FDA is consistent with prior precedent, especially within the precedent of approvals in cardiovascular and heart-specific therapies.

ARCA believes that the pharmacogenetic data generated from the DNA substudy conducted by Drs. Bristow and Liggett create a separate public health rationale for approval of Gencaro. These DNA substudy results are not the primary basis for approval as set forth in the Gencaro NDA, but ARCA believes they will represent an important part of the prescribing information in the label being sought for Gencaro. ARCA believes the genetic

results will provide physicians with a tool to help predict individual patient response prior to therapy. This unique attribute of Gencaro represents a new approach in treating HF, one that ARCA believes has the potential to improve the standard of care.

Licensing and Partnership Obligations

ARCA has licensed worldwide rights to Gencaro, including all preclinical and clinical data, from Cardiovascular Pharmacology and Engineering Consultants, LLC, or CPEC, who has licensed rights in Gencaro from BMS; ARCA has sublicensed CPEC’s rights from BMS. CPEC is a licensing entity which holds the rights of the biotechnology companies that were the commercial sponsors of the BEST trial. Under this license agreement, ARCA is obligated under the CPEC license to make an $8.0 million milestone payment within 180 days after receiving approval from the FDA. ARCA also has the obligation under the CPEC license to make milestone payments of up to $13.0 million in the aggregate upon regulatory marketing approval in the U.S., Europe and Japan. Under the CPEC and BMS licenses, ARCA is obligated to pay royalties based on a percentage of annual sales of Gencaro in any jurisdiction worldwide, which in the aggregate are likely to average from the mid- to high-teens depending on actual annual sales. ARCA has an option to reduce these royalty rates by making a lump-sum payment.

ARCA has also licensed worldwide rights to intellectual property covering the pharmacogenetic response of bucindolol hydrochloride based on the cardiac receptor polymorphisms, which is owned by the University of Colorado. ARCA has no material future financial obligations under this license. ARCA has also licensed the nonexclusive rights to develop and commercialize diagnostics for these receptor polymorphisms, for the purpose of prescribing Gencaro, from the licensee of these rights, CardioDx, Inc. ARCA has certain milestone and royalty obligations under this license agreement, which have been assumed by LabCorp under the parties’ collaboration agreement.

The Gencaro Test

If cleared or approved, ARCA believes that Gencaro will be the first cardiovascular drug to be integrated with a companion diagnostic to predict enhanced efficacy. The drug label being sought for Gencaro would identify the patient receptor genotypes that can expect enhanced efficacy, as well as those with a likelihood of a standard beta-blocker response and the small unfavorable subgroup with a low probability of benefit. The label being sought would recommend receptor genotype testing prior to initiation of therapy. Accordingly, ARCA believes it is critical to the successful commercialization of Gencaro to develop a companion genetic test that is simple to administer and widely available.

ARCA has collaborated with LabCorp to develop and commercialize the Gencaro Test. Under the terms of the collaboration, which has a 10-year term, ARCA has licensed to LabCorp the rights to commercialize a receptor genotype diagnostic for the ß ₁ and µ ₂ _c polymorphisms. In return, LabCorp has agreed to develop the Gencaro Test, obtain FDA clearance or approval of the Gencaro Test, and commercially launch the Gencaro Test in parallel with the commercial launch of Gencaro and in coordination with ARCA’s commercial plan. LabCorp has assumed all financial obligations of ARCA’s license for the diagnostic technology, and retains all the economic benefits.

LabCorp has developed the commercial method for the Gencaro Test, which will use either a blood draw or a cheek swab to obtain a sample. ARCA believes that the Gencaro Test involves a straightforward genetic test that relies on well-validated technology. Based on FDA guidance, LabCorp has submitted a PMA regulatory submission, which was formally accepted by the FDA in January 2009, with the expectation of a decision on approval in the second or third quarter of 2009. LabCorp and ARCA believe that no further clinical trials will be required for the Gencaro Test submission, though there is no guarantee that FDA will not require additional clinical data. The clinical basis for the Gencaro Test will be the clinical studies discussed in ARCA’s NDA for Gencaro, which the LabCorp submission cross-references.

ARCA and LabCorp are developing a joint commercialization and marketing plan, which addresses commercial performance metrics such as turnaround time and distribution, the coordination of the drug and diagnostic sales and marketing programs, and strategies for third-party reimbursement.

Marketing and Sales

ARCA’s strategy is to market Gencaro as the first pharmacogenetically targeted cardiovascular therapy for HF patients. For the U.S. market, ARCA currently plans to build its own specialized sales force, which it expects to be experienced in heart failure and cardiovascular drug sales. Cardiologists specializing in heart failure and selected other physicians will be the focus of ARCA’s specialty sales force. ARCA believes a relatively small number of cardiologists and other heart failure specialists treat a significant percentage of HF patients, and, ARCA believes, also have a disproportionate influence on the prescribing practices of other health care providers that treat HF. Accordingly, ARCA believes that the HF market may be successfully targeted by a specialized sales strategy. Commercialization of Gencaro in the U.S. will require substantial additional capital resources. If sufficient capital is not available on acceptable terms, we may consider alternative commercialization strategies.

Additional elements of ARCA’s U.S. marketing and sales strategy include:

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Publication plan. ARCA has developed a plan that it believes is consistent with applicable federal laws and regulations.

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National and regional key opinion leader development. ARCA plans to develop appropriate contacts with key decision makers in the heart failure market.

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Registry. ARCA intends to develop an observational database integrating genetic and HF data.

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Reimbursement. ARCA plans to implement a comprehensive reimbursement plan for Gencaro and the Gencaro Test in connection with the commercial launch of both products and in compliance with applicable federal requirements.

ARCA holds world-wide rights to Gencaro and has filed its patent applications covering Gencaro in the major international pharmaceutical markets. ARCA plans to accelerate its international commercialization strategy for Gencaro in 2009, by obtaining guidance from foreign regulatory agencies and engaging in discussions with potential international partners.

Competition

If approved, Gencaro will compete against existing beta-blockers approved for HF and their generic equivalents. Currently, there are two beta-blockers (three branded formulations) approved for the treatment of HF in the U.S.:

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TOPROL-XL ^® ;

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Coreg ^® and Coreg CR ^® (a sustained release formulation)

TOPROL-XL and immediate release Coreg have generic equivalents commercially available in the U.S. (Metoprolol Succinate and Carvedilol respectively). It is anticipated that both of these generic equivalents will be priced at less than the price of Gencaro. During the 12-month period ended January 31, 2009, total sales of beta-blockers approved for use in HF were approximately $4.6 billion in the U.S., with generic formulations accounting for a substantial majority of the market. ARCA estimates up to 50% of these revenues could be attributable to patients with heart failure. While reports vary on the proportion of the beta-blocker market represented by heart failure, ARCA believes HF contributes to a significant portion of the U.S. market.

The companies that sell the existing therapies are much larger than ARCA and have much greater resources. In addition, ARCA’s proposed prescribing information for Gencaro includes a recommendation for genetic

testing, which will add additional cost and procedures to the process of prescribing Gencaro, and which could make it more difficult for ARCA to compete against existing therapies.

Additionally, Gencaro may also compete against existing therapies whose follow-on indications may include treatment for HF. For example, Forest Laboratories may apply for approval to use Bystolic, a drug currently used to treat high blood pressure, for treatment of heart failure. If approved for treatment of heart failure, Gencaro may not be successful in competing against Bystolic, an already well-known name brand.

Other Potential Indications for Gencaro

ARCA is exploring the potential of Gencaro for the prevention of atrial fibrillation, and/or ventricular tachycardia/ventricular fibrillation. ARCA believes these could be attractive follow-on indications. ARCA believes that data from the BEST trial suggests that Gencaro has potential for these indications, and that the clinical response is also pharmacogenetic, based on the same genetic markers that stratify response on HF endpoints.

Development Pipeline

ARCA intends to leverage its management’s experience in cardiovascular research, genetics, clinical development, and commercialization to acquire and develop other cardiovascular products or candidates, with an emphasis on pharmacogenetic applications. ARCA is evaluating further clinical development of NU172, a novel, short-acting anticoagulant, as a potential new therapy in indications where heparin paired with its antidote, protamine, are the current standard of care, such as CABG surgery, kidney dialysis and a variety of vascular surgical and coronary interventions.

NU172 is an aptamer, a single-stranded nucleic acid that forms a well-defined, three-dimensional shape conceptually similar to an antibody. NU172 was designed to directly inhibit thrombin’s ability to stimulate blood clot formation in the setting of medical or surgical procedures where human blood is exposed to foreign materials. ARCA believes that NU172 has potential as a therapy for use in CABG surgeries, kidney dialysis, and other vascular and coronary interventions. Approximately 450,000 CABG procedures and 50 million dialysis procedures are performed annually in the U.S. In these procedures, heparin is often paired with its antidote protamine as the anticoagulation effect of heparin needs to be reversed once the procedure has been completed. Data from the Phase I trial and preclinical studies suggest that NU172 has the potential to produce rapid and predictable onset and offset of anticoagulation, work in stagnant blood, avoid thrombocytopenia, and has the potential for non-renal clearance. These studies also suggest that NU172 may have a short half-life in patients, giving it the potential to be rapidly reversed without the need for an antidote.

The development of NU172 is subject to a collaboration agreement with Archemix Corporation, under which ARCA is responsible for development and worldwide commercialization of NU172 and other potential product candidates that may be developed under this collaboration. In February 2008, Nuvelo paid Archemix a $1.0 million milestone fee in connection with the dosing of the first patient in the Phase I trial for NU172. If ARCA enrolls the first patient in a Phase II trial of NU172, ARCA will be obligated to pay Archemix a $3.0 million milestone fee.

Manufacturing and Product Supply

Gencaro is a small molecule drug with an established manufacturing history. Multiple manufacturers of both the API and drug product have successfully produced Gencaro for use in clinical trials over the course of its clinical development. ARCA outsources all manufacturing and analytical testing of the API of Gencaro and the drug product. Third party contract manufacturing organizations have been selected by ARCA on the basis of their technical and regulatory expertise. ARCA’s approach with its contract manufacturing partners has been to replicate the manufacturing processes that were used to support the pivotal clinical trials with Gencaro, and to minimize any changes from these baseline processes, thereby reducing technical and regulatory risk.

ARCA has contracted with Groupe Novasep to manufacture commercial quantities of the API for Gencaro. Registration batches have been completed to support the NDA submission for Gencaro, with all batches meeting specifications.

For drug product production, ARCA has contracted with Patheon, Inc. to manufacture the Gencaro tablets. Gencaro is produced in a tablet form, utilizing standard solid oral dosage processing techniques. Six separate dosage strengths are manufactured, with the maximum recommended dose of 50mg twice daily for patient weighing 75kg or less and 100mg twice daily for patients weighing more than 75kg. This is consistent with dosages studied in pivotal clinical trials of Gencaro, and ARCA believes they support the appropriate titration and chronic dosages required for HF patients. Registration batches have been successfully completed to support the NDA submission for Gencaro.

ARCA’s manufacturing focus for the remainder of 2009 will be to complete the process validation programs and to build product inventory in anticipation of potential commercial launch. ARCA believes both facilities have adequate production capacity to support the projected market demand for Gencaro.

Research and Development Expenses

For the years ended December 31, 2008 and 2007, Nuvelo incurred research and development expenses of $27.8 million and $42.7 million, respectively. For the years ended December 31, 2008 and 2007, ARCA incurred research and development expenses of $11.0 million and $10.2 million, respectively. During 2009, ARCA expects to focus its research and development efforts on obtaining Gencaro approval, investigating potential new indications, developing an international regulatory strategy and furthering its cardiovascular pipeline development. Due to the significant reduction in the scope of Nuvelo’s research and development efforts, ARCA anticipates a significant reduction in combined research and development spending in 2009 as compared with 2008.

Government Regulation

Governmental authorities in the U.S. at the federal, state, and local levels and foreign countries extensively regulate, among other things, the research, development, testing, manufacture, labeling, promotion, advertising, marketing, distribution, sampling, and import and export of pharmaceutical and medical device products.

Premarket Approval of Drugs

FDA approval is required before any new drug, dosage form, indication, or strength can be marketed in the U.S. ARCA anticipates that all of its products will require regulatory approval by governmental agencies prior to commercialization. The process of obtaining approval and the subsequent process of maintaining compliance with appropriate federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. In addition, these statutes, rules, regulations and policies may change and ARCA’s products may be subject to new legislation or regulations. There are numerous FDA and other federal and state sanctions for non-compliance.

The steps required before new human therapeutic products are marketed in the U.S. and foreign countries include rigorous preclinical and clinical testing and other approval requirements by regulatory agencies, such as the FDA and comparable agencies in foreign countries.

Preclinical Phase. Preclinical studies are generally conducted in the laboratory to evaluate the potential efficacy and safety of a product candidate. These studies include laboratory evaluation of product chemistry, formulation and stability, as well as studies to evaluate toxicity in animals. Preclinical studies are governed by numerous regulations.

Clinical Phase. Before human clinical trials can commence, an Investigational New Drug, or IND, application, submitted to FDA must become effective. The clinical phase of development involves the performance of human studies, including adequate and well-controlled human clinical trials to establish the safety and efficacy of the product candidate for each proposed indication. Typically, clinical evaluation involves three sequential phases, which may overlap. During Phase I, clinical trials are conducted with a relatively small number of subjects or patients to determine the early safety profile of a product candidate, as well as dose tolerance, absorption, and the pattern of drug distribution and drug metabolism. In Phase II, trials are conducted with groups of patients afflicted by a specific target disease to determine preliminary efficacy, optimal dosages and dosage tolerance and to identify possible adverse effects and safety risks. In Phase III, larger-scale, multi-center trials are conducted with patients afflicted with a specific target disease to provide data for the statistical proof of efficacy and safety as required by regulatory agencies. The conduct of the clinical trials is subject to extensive regulation.

NDA Submission. In the U.S., the results of preclinical and clinical testing along with chemistry, manufacturing and controls information, are submitted to the FDA in the form of an NDA. In September 2008, the FDA formally accepted for filing ARCA’s NDA for Gencaro as a potential treatment for chronic heart failure.

Under PDUFA, after submission of an NDA and payment, or waiver, of the required fee, the FDA’s goal is to review most standard NDAs within 10 months from acceptance of the application to the time the FDA decides to issue a “complete response,” or approve the NDA. The PDUFA date for Gencaro is May 31, 2009. The review process is often significantly extended by FDA requests for additional information or clarification. The FDA may ultimately decide that the NDA does not satisfy the criteria for approval.

In responding to an NDA, the FDA may grant marketing approval or deny the application if the FDA determines that the application does not satisfy the statutory and regulatory approval criteria. A denial may include a request for additional information, including additional clinical data and/or an additional Phase III clinical trial. Data from clinical trials are not always conclusive and FDA may interpret data differently than ARCA interprets data. For instance, ARCA believes that results from a single Phase III study, the BEST study, are sufficient to support approval of Gencaro’s NDA. Under the Food and Drug Modernization Act of 1997, the FDA is authorized to approve a drug based on a single adequate and well-controlled study if such study and other confirmatory data are sufficient to establish the drug’s effectiveness. However, it has long been the FDA’s general position that the standard of proof of a drug’s effectiveness generally requires at least two well-controlled and adequate Phase III clinical studies with p-values of less than 0.05 on the primary endpoint.

In addition, in accordance with current FDA law and regulations, the FDA may refer a drug to an advisory committee for review prior to approval. In some cases, FDA may require completion, within a specified time period, of additional clinical studies after approval, referred to as Phase IV clinical studies, to monitor the effect of a new product and may prevent or limit future marketing of the product based on the results of these post-marketing programs. Furthermore, prior to granting approval, the FDA generally conducts an inspection of the facilities, including outsourced facilities that will be involved in the manufacture, production, packaging, testing and control of the drug substance and finished drug product for compliance with current Good Manufacturing Practice, or cGMP, requirements.

If the FDA approves the NDA, the sponsor is authorized to begin commercialization of the drug in accordance with the approval. Even if the FDA approves the NDA, the agency may decide later to suspend or withdraw product approval if compliance with regulatory standards is not maintained or if safety problems are recognized after the product reaches the market. In addition, the FDA requires surveillance programs to monitor approved products that have been commercialized, and the agency has the power to require additional clinical studies, to require changes in labeling or to prevent further marketing of a product based on the results of these post-marketing programs. The FDA also has authority to request implementation of a risk evaluation and mitigation strategy, or REMS, that could restrict distribution of Gencaro or require ARCA to provide additional risk information to prescribers.

Whether or not FDA approval has been obtained, approval of a product candidate by comparable foreign regulatory authorities is necessary prior to the commencement of marketing of a product candidate in those countries. The approval procedures vary among countries and can involve additional testing. The time required to obtain approval may differ from that required for FDA approval. Although there are some centralized procedures for filings in the European Union countries, in general each country has its own procedures and requirements.

Post-approval Compliance. If regulatory approval for a drug or medical device is obtained, the product and the facilities manufacturing the product are subject to periodic inspection and continued regulation by regulatory authorities, including compliance with cGMP, as well as labeling, advertising, promotion, recordkeeping, and reporting requirements, including the reporting of adverse events. In addition, the FDA closely regulates the post-approval marketing and promotion of drugs, including standards and regulations for direct-to-consumer advertising, off-label promotion, industry-sponsored scientific and educational activities and promotional activities involving the Internet. Drugs may be marketed only for the approved indications and in accordance with the provisions of the approved label. Failure to comply with these requirements can result in adverse publicity, warning letters, corrective advertising and potential civil and criminal penalties.

Drug Price Competition and Patent Term Restoration Act of 1984. Under the Drug Price Competition and Patent Term Restoration Act of 1984, also known as the Hatch-Waxman Act, Congress created an abbreviated FDA review process for generic versions of pioneer (brand name) drug products. The Hatch-Waxman Act also provides for patent term restoration and the award, in certain circumstances, of non-patent marketing exclusivities.

Generic Drug Approval . The Hatch-Waxman Act established an abbreviated FDA review process for drugs that are shown to be equivalent to approved pioneer drugs. Approval for a generic drug is obtained by filing an abbreviated NDA, or ANDA. Generic drug applications are “abbreviated” because they generally do not include clinical data to demonstrate safety and effectiveness. Instead, an ANDA applicant must establish that its product is bioequivalent to an approved drug and that it is the same as the approved drug with respect to active ingredient(s), route of administration, dosage form, strength and recommended conditions of use (labeling). The FDA will approve the generic as suitable for an ANDA if it finds that the generic does not raise questions of safety and effectiveness as compared to the pioneer drug. A drug is not eligible for ANDA approval if the FDA determines that it is not equivalent to the pioneer drug or if it is intended for a different use. Any applicant who files an ANDA seeking approval of a generic version of an approved drug listed in FDA’s Approved Drug Products with Therapeutic Equivalence Evaluations, or the Orange Book, before expiration of the patent(s) listed in the Orange Book for that approved drug, must certify to the FDA for each patent that (i) no patent information on the drug has been submitted to the FDA; (ii) that such patent has expired; (iii) the date on which such patent expires; or (iv) that such patent is invalid, unenforceable or will not be infringed by the manufacture, use or sale of the generic drug. If the ANDA applicant makes a Paragraph IV certification and the NDA holder files an infringement suit against the ANDA applicant within 45 days of receiving the paragraph IV notification, the NDA owner is entitled to an automatic 30-month stay of FDA’s ability to approve the ANDA. This 30-month stay will end early upon any decision by a court that the patent is invalid, unenforceable or not infringed by the generic drug.

Patent Term Restoration. The Hatch-Waxman Act provides for the restoration of a portion of the patent term lost during product development and FDA review of an application. However, the maximum period of restoration cannot exceed five years, or restore the total remaining term of the patent to greater than 14 years from the date of FDA approval of the product.

Non-Patent Marketing Exclusivities. Separate and apart from patent protection, the Hatch-Waxman Act entitles approved drugs to various periods of non-patent statutory protection, known as marketing exclusivity. The Hatch-Waxman Act provides five years of “new chemical entity” marketing exclusivity to the first applicant to gain approval of an NDA for a product that contains an active moiety not found in any other approved product. This exclusivity means that another manufacturer cannot submit an ANDA or 505(b)(2) NDA until the marketing

exclusivity period ends. This exclusivity protects the entire new chemical entity franchise, including all products containing the active ingredient for any use and in any strength or dosage form, but will not prevent the submission or approval of stand-alone NDAs where the applicants have conducted their own clinical studies to demonstrate safety and effectiveness. There is an exception, however, for a competitor that seeks to challenge a patent with a Paragraph IV certification. Four years into the five-year exclusivity period, a manufacturer who alleges that one or more of the patents listed with the NDA is invalid, unenforceable or not infringed may submit an ANDA or 505(b)(2) NDA for a generic or modified version of the product.

The Hatch-Waxman Act also provides three years of “new use” marketing exclusivity for the approval of NDAs, and supplements, where those applications contain the results of new clinical investigations (other than bioavailability studies) essential to the FDA’s approval of the applications. Such applications may be submitted for new indications, dosage forms, strengths, or new conditions of use of approved products. So long as the studies are essential to the FDA’s approval or were conducted by or for the applicant, this three-year exclusivity prohibits the final approval of ANDAs or 505(b)(2) NDAs for products with the specific changes associated with those studies. It does not prohibit the FDA from approving ANDAs or 505(b)(2) NDAs for other products containing the same active ingredient, without those changes.

FDA Approval of Medical Devices

Based on FDA guidance, LabCorp has submitted a PMA regulatory submission, which was formally accepted by the FDA in January 2009, with the expectation of a decision on approval in the second or third quarter of 2009.

Unless an exemption applies, each medical device that a company wishes to market in the U.S. will require either approval of a PMA or 510(k) clearance from the FDA. The FDA classifies medical devices into one of three classes. Devices deemed to pose lower risks are placed in either class I or II, which may require the manufacturer to submit to the FDA a 510(k) requesting permission to commercially distribute the device. This process is generally known as 510(k) clearance. Some low risk devices are exempted from this requirement. Devices deemed by the FDA to pose the greatest risks, or for which there is no predicate, are placed in class III, requiring approval of a PMA.

PMA Pathway . Generally, a PMA must be supported by extensive data including, but not limited to, technical, preclinical, clinical trials, manufacturing and labeling to demonstrate to the FDA’s satisfaction a reasonable assurance of the safety and effectiveness of the device for its intended use. After a PMA is sufficiently complete, the FDA will accept the application and begin an in-depth review of the submitted information and will generally conduct a pre-approval inspection of the manufacturing facility or facilities to ensure compliance. By statute, the FDA has 180 days to review the “accepted application”, although, generally, review of the application can take between one and three years, but it may take significantly longer.

Clinical Trials. Clinical trials are generally required to support a PMA application and are sometimes required for 510(k) clearance. Based on discussions with FDA, ARCA believes that the clinical trials in the Gencaro NDA are sufficient to support the Gencaro Test submission and that no further clinical trials will be required. Following the FDA’s guidance from these discussions, the Gencaro Test regulatory filing cross-referenced the Gencaro NDA.

Continuing Regulation. After a device is placed on the market, numerous regulatory requirements apply to the manufacturer, or holder of a PMA approval. With respect to the Gencaro Test, LabCorp will be responsible for compliance with such requirements. The FDA has broad post-market and regulatory enforcement powers. Accordingly, LabCorp’s facilities and the manufacturing facilities of certain of its suppliers will be subject to inspections by the FDA to determine those facilities’ level of compliance with various regulations.

International Marketing Approvals. International sales of medical devices are subject to foreign government regulations, which vary substantially from country to country and are subject to change. The time required to

obtain approval by a foreign country may be longer or shorter than that required for FDA clearance or approval, and the requirements may differ.

Other Regulatory Requirements. ARCA is also subject to various federal, state and local laws, regulations and recommendations relating to safe working conditions, laboratory and manufacturing practices, the experimental use of animals and the use and disposal of hazardous or potentially hazardous substances, including radioactive compounds and infectious disease agents, used in connection with ARCA’s work. The extent and character of governmental regulation that might result from future legislation or administrative action cannot be accurately predicted.

Intellectual Property

The future success of ARCA’s business will partly depend on its ability to maintain market exclusivity in the United States and important international markets for Gencaro, and for other products or product candidates that it may acquire or develop. ARCA will rely on statutory protection, patent protection, trade secrets, know-how, and in-licensing of technology rights to maintain protection for its products.

ARCA believes that both patent protection and data exclusivity statutes will give Gencaro market exclusivity in the U.S. and in major international markets. Upon approval by the FDA or international regulatory agencies, Gencaro will qualify as a New Chemical Entity, or NCE, as it has never received regulatory approval in any jurisdiction. As an NCE, Gencaro will enjoy market exclusivity in the United States and most international markets under data exclusivity statutes. These laws provide for an exclusivity period beginning from regulatory approval, during which any generic competitor is barred from submitting an application that relies on the data that has been submitted in connection with the approval of the NCE. In the U.S., the Hatch-Waxman Act provides for an initial period of four or five years from approval of the NCE, during which a generic application attempting to rely on the data submitted for the NCE cannot be filed with FDA. This period can be extended under certain circumstances, and ARCA believes that the maximum period of exclusivity under these provisions is seven and one-half years from FDA approval, as discussed below.

Many international markets have data exclusivity statutes that are analogous to Hatch-Waxman and often more protective. The analogous statute in the European Medicines Evaluation Agency will, in general, provide Gencaro with a minimum of ten years of protection before such a generic application may be approved. Protection under Hatch-Waxman and other data exclusivity statutes is sometimes considered superior to patent protection, as the generic cannot be marketed during the period of exclusivity, thus eliminating the need to initiate patent infringement litigation with its accompanying risks and costs.

In addition to protection under data exclusivity statutes, ARCA believes that its patent portfolio will extend Gencaro’s market exclusivity. ARCA has filed patent applications in the United States and in major international markets that claim the use of Gencaro with the genetic polymorphisms of the ß ₁ and µ _2c receptors that predict Gencaro response. ARCA believes that this patent strategy will effectively serve to exclude generic competition, if the prescribing information in the Gencaro label includes a recommendation to genotype patients, a use covered by the patent applications. Consequently, if the patents are granted and ARCA’s patent strategy is successful, ARCA believes that the possibility of generic competition with Gencaro will be significantly reduced until the expiration of these patents, which would be in 2025. ARCA also believes that if these patents are granted, the initial period of statutory exclusivity for Gencaro in the U.S. may be extended to seven and one-half years from approval, under a special Hatch-Waxman provision that permits an automatic 30-month extension of the exclusivity period by pursuing litigation against any company attempting to enter the market with a generic for a drug that is covered by a composition of matter or method of use patent.

ARCA also owns or has rights in a number of patents and patent applications relating to a number of clinical candidate molecules, including NU172. ARCA estimates that the primary patents for NU172 would expire in the U.S. and in Europe in 2026.

In some cases, certain of the U.S. patents may be entitled to an extension of their term and certain European patents may be entitled to supplemental protection in one or more countries in Europe. The length of any such extension, if an extension is granted, will vary by country. ARCA cannot predict whether any such extensions will be granted.

Employees

As of February 28, 2009, the Company had 85 employees, 81 of whom are full-time, including 21 of Nuvelo’s employees who have been retained for a transition period of up to 12 weeks from the closing date of the merger. Most of these employees operate out of the Broomfield, Colorado, and San Carlos, California locations while others operate from home-based offices in other states. None of the Company’s employees are represented by any collective bargaining unit. The Company believes that it maintains good relations with its employees.

Corporate Information

Nuvelo was originally incorporated as Hyseq, Inc. in Illinois in 1992 and reincorporated in Nevada in 1993. On January 31, 2003, Nuvelo merged with Variagenics, Inc., a publicly traded Delaware corporation based in Massachusetts, and, in connection with the merger, changed its name to Nuvelo, Inc. On March 25, 2004, Nuvelo was reincorporated from Nevada to Delaware. On January 27, 2009, in connection with the merger described above, Nuvelo changed its name to ARCA biopharma, Inc. The Company has two wholly-owned subsidiaries, Hyseq Diagnostics, Inc., which is inactive, and ARCA biopharma Colorado, Inc. Its principal offices are located in Broomfield, Colorado. It also has facilities in San Carlos, California.

The Company files its annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 electronically with the SEC. The public may read or copy any materials that have been filed with the SEC at the SEC’s Public Reference Rooms at 100 F Street, N.E., Washington, D.C. 20549. The public may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC. The address of that site is http://www.sec.gov.

You may obtain a free copy of the Company’s annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports on the Company’s website at http://www.arcabiopharma.com on the earliest practicable date following the filing with the SEC or by contacting the Investor Relations Department at the Company’s corporate office by calling (720) 940-2200. Information found on the Company’s website is not incorporated by reference into this report.

Item 1A.

Risk Factors

An investment in our securities involves certain risks, including those set forth below and elsewhere in this report. In addition to the risks set forth below and elsewhere in this report, other risks and uncertainties not known to us, that are beyond our control or that we deem to be immaterial may also materially adversely affect our business operations. All of the following risks could materially and adversely affect our business, financial condition or results of operations. In such a case, you could lose all of or a part of your original investment. You should carefully consider the risks described below as well as other information and data included in this report.

Risks Related to ARCA’s Business

Transitioning from a developmental stage company will require successful completion of a number of steps, many of which are outside of ARCA’s control and, consequently, ARCA can provide no assurance of its successful and timely transition from a developmental stage company.

ARCA is a development stage biopharmaceutical company with a limited operating history. In addition, to date ARCA has not generated any product revenue and has historically funded its operations through investment capital. ARCA’s future growth depends on its ability to emerge from the developmental stage and successfully commercialize Gencaro and its other product candidates, which in turn, will depend, among other things, on ARCA’s ability to:

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develop and obtain regulatory approval for Gencaro or other product candidates;

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successfully partner a companion genetic test with the commercial launch of Gencaro;

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build an internal specialty sales and marketing capability or enter into agreements with third parties to provide sales and marketing functions;

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pursue additional indications for Gencaro and develop other product candidates, including other cardiovascular therapies;

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raise additional capital to support the commercialization of Gencaro and other product candidates;

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increase the size of its organization;

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obtain commercial quantities of Gencaro or other product candidates at acceptable cost levels; and

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successfully conduct and complete clinical trials for Gencaro and other product candidates.

Any one of these factors or other factors discussed in this annual report could affect ARCA’s ability to successfully commercialize Gencaro and other product candidates, which could impact ARCA’s ability to earn sufficient revenues to transition from a developmental stage company and continue its business.

If ARCA is not able to obtain FDA approval and successfully develop and commercialize Gencaro or another product candidate in a timely manner, it may not be able to continue its business operations.

ARCA currently has no products that have received regulatory approval for commercial sale. The process to develop, obtain regulatory approval for and commercialize potential product candidates is long, complex and costly. The Gencaro NDA is currently under FDA review. Gencaro is ARCA’s only product candidate at a late stage of clinical development. As a result, ARCA’s business is substantially dependent on its ability to obtain regulatory approval for and successfully commercialize Gencaro in a timely manner.

In addition to Gencaro, ARCA currently plans to develop other product candidates, and is evaluating further clinical development of NU172, which has completed one Phase I clinical trial. This product candidate must be rigorously tested in clinical trials, and be shown to be safe and effective, before the FDA or other regulatory authorities outside the U.S. will consider it for approval.

Failure to demonstrate that one or more of ARCA’s product candidates is safe and effective, or significant delays in demonstrating such safety and efficacy, could adversely affect ARCA’s business. Failure to obtain marketing approval of one or more of ARCA’s product candidates from appropriate regulatory authorities, or significant delays in obtaining such approval, could also adversely affect ARCA’s business. If approved for sale, ARCA’s product candidates must be successfully commercialized. Failure to successfully commercialize one or more of ARCA’s product candidates could damage ARCA’s business, and, in particular, if the NDA for Gencaro is not approved, or is substantially delayed, or if ARCA is unable to successfully commercialize Gencaro, it may not be able to earn sufficient revenues to continue its business.

If ARCA is unable to establish a direct sales force in the U.S., its business may be harmed.

ARCA is currently building its sales organization. If Gencaro is approved by the FDA for commercial sale, ARCA intends to market Gencaro in the U.S. to physicians, hospitals and other health care providers using its own sales force. While certain ARCA employees have experience in establishing and managing a sales force, these employees have no such experience since being with ARCA. Commercialization of Gencaro in the U.S., particularly the establishment of a sales organization, will require substantial additional capital resources. If sufficient capital is not available on acceptable terms, we would need to consider alternative commercialization strategies for Gencaro. ARCA will need to incur significant additional expenses and commit significant additional management resources to establish a sufficient sales force for Gencaro.

ARCA may not be able to successfully establish these capabilities even if it is able to secure sufficient capital resources for its commercialization efforts. If ARCA elects to rely on third parties to sell Gencaro and any other products, then it may receive less revenue than if it sold such products directly. In addition, ARCA may have little or no control over the sales efforts of those third parties. In the event ARCA is unable to sell Gencaro and other selected product candidates, either directly or through third parties, the commercialization of Gencaro may be delayed indefinitely and ARCA’s business may be harmed

ARCA is relying upon LabCorp to obtain marketing clearance or approval of the companion Gencaro Test. There is no guarantee that the FDA will grant timely clearance or approval of the Gencaro Test, if at all, and failure to obtain such timely clearance or approval would adversely affect ARCA’s ability to market Gencaro.

The drug label being sought for Gencaro would identify the patient receptor genotypes with a potential for enhanced efficacy, as well as those with a likelihood of a standard beta-blocker response and the smaller unfavorable subgroup with a low probability of benefit. Accordingly, ARCA believes it will be critical to the successful commercialization of Gencaro to develop a companion genetic test, or the Gencaro Test, that is simple to administer and widely available.

The Gencaro Test is subject to regulation by the FDA and by comparable agencies in various foreign countries. The process of complying with the requirements of the FDA and comparable agencies is costly, time consuming and burdensome.

Under ARCA’s agreement with LabCorp, LabCorp is responsible for determining the appropriate regulatory pathway for the Gencaro Test and obtaining market clearance or approval from the FDA. Based on FDA guidance, LabCorp has submitted a PMA regulatory submission, which the FDA formally accepted in January 2009. The FDA may decide that the Gencaro Test should be evaluated for clearance under the FDA’s 510(k) notification process. LabCorp and ARCA do not believe that any further clinical trials will be required for the Gencaro Test PMA, though there is no guarantee that FDA will not require additional clinical data.

Despite the time and expense expended, regulatory clearance or approval is never guaranteed. If regulatory clearance or approval is delayed, or if LabCorp is unable to obtain FDA approval of the Gencaro Test at all or in parallel with the approval of Gencaro, or is unable to commercialize the test successfully and in a manner that effectively supports ARCA’s commercial efforts, or if the information concerning the differential response to

Gencaro resulting from certain genetic variation is not included in the approval label for Gencaro, the commercial launch of Gencaro may be significantly and adversely affected. In such cases, ARCA could be forced to identify a new third-party test provider and obtain regulatory approval for that provider’s genetic test, which could substantially delay and negatively affect the commercial prospects for Gencaro.

Future sales of Gencaro may suffer if its marketplace acceptance is negatively affected by the Gencaro Test.

The Gencaro Test is an important component of the commercial strategy for Gencaro. ARCA believes that the Gencaro Test helps predict patient response to Gencaro, and that this aspect of the drug is important to its ability to compete effectively with current therapies. The Gencaro Test adds an additional step in the prescribing process, an additional cost for the patient and payors, the risk that the test results may not be rapidly available and the possibility that it may not be available at all to hospitals and medical centers. Although ARCA anticipates that Gencaro will be the first genetically-targeted cardiovascular drug, Gencaro will be one of a number of successful drugs in the beta-blocker class currently on the market. Prescribers may be more familiar with these other beta-blockers, and may be resistant to prescribing Gencaro as an HF therapy without efforts on ARCA’s part to educate prescribers. Any one of these factors could affect prescriber behavior, which in turn may substantially impede market acceptance of the Gencaro Test, which could cause significant harm to Gencaro’s ability to compete, and in turn harm ARCA’s business.

ARCA will need to significantly increase the size of its organization and may experience difficulties in managing its growth.

ARCA expects that it will need to substantially increase and modify its operations in the future to commercialize Gencaro and to conduct clinical trials for and commercialize any additional indications or markets for Gencaro and any future product candidates that ARCA acquires or develops, as well as to support the administrative functions of a public company. Future growth will impose significant added responsibilities on members of management, including the need to identify, recruit, retain and integrate additional employees. ARCA’s future financial performance and its ability to commercialize its product candidates and to compete effectively will depend, in part, on its ability to manage any future growth effectively. To that end, ARCA must be able to:

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manage its clinical trials effectively;

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integrate current and additional management, administrative, financial and sales and marketing personnel;

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hire new personnel necessary to effectively commercialize product candidates it licenses;

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develop its administrative, accounting and management information systems and controls; and

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hire and train additional qualified personnel.

Unless ARCA is able to generate sufficient product revenue, ARCA will continue to incur losses from operations and may not achieve or maintain profitability.

ARCA’s historical losses, among other things, have had and will continue to have an adverse effect on ARCA’s stockholders’ equity and working capital. Even if ARCA receives regulatory approval for any of its product candidates, including Gencaro, sales of such products may not generate sufficient revenue for it to achieve or maintain profitability. ARCA expects to incur increased general and administrative expenses and higher sales and marketing expenses. As a result, it expects to continue to incur significant and increasing operating losses for the foreseeable future. Because of the numerous risks and uncertainties associated with developing therapeutic drugs, ARCA may experience larger than expected future losses and may never reach profitability.

ARCA is dependent on key personnel, and it must attract and retain qualified employees, collaborators and consultants.

The success of ARCA’s business is highly dependent on the principal members of ARCA’s scientific and management staff, including its Chairman of the Board, Michael R. Bristow, and its President and Chief Executive Officer, Richard, B. Brewer. The loss of the services of any such individual might seriously harm ARCA’s product development efforts. Recruiting and training personnel with the requisite skills is challenging and extremely competitive.

ARCA’s product candidates are subject to extensive regulation, which can be costly and time-consuming, and unsuccessful or delayed regulatory approvals could increase ARCA’s future development costs or impair ARCA’s future revenue.

The preclinical and clinical development, testing, manufacture, safety, efficacy, labeling, storage, recordkeeping, advertising, promotion, sale, and marketing, and distribution of ARCA’s product candidates are subject to extensive regulation by the FDA and other regulatory authorities in the United States and elsewhere. These regulations also vary in important, meaningful ways from country to country. ARCA is not permitted to market a potential drug in the United States until ARCA receives approval of an NDA from the FDA. ARCA has not received an NDA approval from the FDA for any of its product candidates. There can be no guarantees with respect to ARCA’s product candidates that clinical studies will adequately support an NDA, that the products will receive necessary regulatory approvals, or that they will prove to be commercially successful.

To receive regulatory approval for the commercial sale of any product candidates, ARCA must demonstrate safety and efficacy in humans to the satisfaction of regulatory authorities through preclinical studies and adequate and well-controlled clinical trials of the product candidates. This process is expensive and can take many years, and failure can occur at any stage of the testing. ARCA’s failure to adequately demonstrate the safety and efficacy of its product candidates will prevent regulatory approval and commercialization of such products. With respect to Gencaro, the FDA could determine that the preclinical studies and clinical trials conducted by or on Gencaro’s behalf were inadequate, and such a determination would prevent regulatory approval and commercialization of Gencaro. For instance, ARCA filed an NDA for Gencaro in July 2008, based primarily on a single Phase III trial. The FDA guidelines generally suggest that sponsors conduct two adequate and well-controlled studies to demonstrate the safety and efficacy of a product candidate such as Gencaro in support of FDA approval. FDA interpretation of the statutory requirements also states that a single study may be sufficient to support approval if the FDA determines that, based on relevant science and other confirmatory evidence, there is strong evidence to establish the safety and efficacy of the drug candidate using a single adequate and well-controlled study. If the FDA determines that the clinical data for Gencaro is not sufficiently strong to demonstrate Gencaro’s safety and efficacy for chronic heart failure, then Gencaro may not be approved by the FDA for ARCA’s proposed indications, may be approved for a more limited indication, or the FDA may require ARCA to conduct additional studies before approving Gencaro for chronic heart failure. Even if ARCA conducted additional studies and submitted the attendant data, FDA may ultimately decide that the NDA does not satisfy the criteria for approval.

In the event that ARCA or its collaborators conduct preclinical studies that did not comply with Good Laboratory Practices or incorrectly design or carry out human clinical trials or those clinical trials fail to demonstrate clinical significance, ARCA will not likely be able to obtain FDA approval for product development candidates. ARCA’s inability to successfully and effectively complete clinical trials for any product candidates on schedule or at all will severely harm ARCA’s business. Significant delays in clinical development could materially increase product development costs or allow ARCA’s competitors to bring products to market before it does, impairing ARCA’s ability to effectively commercialize any future product candidates. ARCA does not know whether planned clinical trials will begin on time, will need to be redesigned or will be completed on schedule, if at all. Clinical trials can be delayed for a variety of reasons, including:

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delays or failures in obtaining regulatory authorization to commence a trial because of safety concerns of regulators relating to ARCA’s product candidates or similar product candidates of ARCA’s competitors or failure to follow regulatory guidelines;

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delays or failures in obtaining clinical materials and manufacturing sufficient quantities of the product candidate for use in trials;

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delays or failures in reaching agreement on acceptable terms with prospective study sites;

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delays or failures in obtaining approval of ARCA’s clinical trial protocol from an institutional review board, or IRB, to conduct a clinical trial at a prospective study site;

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delays in recruiting patients to participate in a clinical trial, which may be due to the size of the patient population, eligibility criteria, protocol design, perceived risks and benefits of the drug, availability of other approved and standard of care therapies, availability of clinical trial sites;

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other clinical trials seeking to enroll subjects with similar profile;

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failure of ARCA’s clinical trials and clinical investigators to be in compliance with the FDA’s Good Clinical Practices;

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unforeseen safety issues, including negative results from ongoing preclinical studies;

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inability to monitor patients adequately during or after treatment;

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difficulty monitoring multiple study sites; and

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failure of ARCA’s third-party contract research organizations, clinical site organizations and other clinical trial managers, to satisfy their contractual duties, comply with regulations or meet expected deadlines.

In addition, any approvals ARCA may obtain may not cover all of the clinical indications for which it seeks approval. In addition, if ARCA chooses to make claims of superiority over currently marketed competitive products, ARCA must substantiate those claims with scientific evidence from prospectively designed head-to-head clinical trials. Also, an approval might contain significant limitations in the form of narrow indications, warnings, precautions or contraindications with respect to conditions of use. If the FDA determines that a risk evaluation and mitigation strategy, or REMS, is necessary to ensure that the benefits of the drug outweigh the risks, ARCA may be required to include as part of the NDA a proposed REMS that may include a package insert directed to patients, a plan for communication with healthcare providers, restrictions on a drug’s distribution, or a Medication Guide to provide better information to consumers about the drug’s risks and benefits. Finally, an approval could be conditioned on ARCA’s commitment to conduct further clinical trials, which ARCA may not have the resources to conduct or which may negatively impact ARCA’s financial situation.

In September 2008, the FDA formally accepted for filing ARCA’s NDA, for Gencaro, with the goal of completing its review of the NDA by May 31, 2009. Filing of the NDA indicates that the application is sufficiently complete to allow for FDA to review ARCA’s data supporting the safety profile and effectiveness of Gencaro, but does not guarantee approval. All of ARCA’s product candidates are prone to the risks of failure inherent in drug development. The results from preclinical animal testing and early human clinical trials may not be predictive of results obtained in later human clinical trials. Further, although a new product may show promising results in preclinical or early human clinical trials, it may subsequently prove unfeasible or impossible to generate sufficient safety and efficacy data to obtain necessary regulatory approvals. The data obtained from preclinical and clinical studies are susceptible to varying interpretations that may delay, limit or prevent regulatory approval, and the FDA and other regulatory authorities in the United States and elsewhere exercise substantial discretion in the drug approval process. The numbers, size and design of preclinical studies and clinical trials that will be required for FDA or other regulatory approval will vary depending on the product candidate, the disease or condition for which the product candidate is intended to be used and the regulations and guidance documents applicable to any particular product candidate. The FDA or other regulators can delay, limit or deny approval of any product candidate for many reasons, including, but not limited to:

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side effects;

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safety and efficacy;

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defects in the design of clinical trials;

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the fact that the FDA or other regulatory officials may not approve ARCA’s or ARCA’s third party manufacturer’s processes or facilities; or

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the fact that new regulations may be enacted by the FDA or other regulators may change their approval policies or adopt new regulations requiring new or different evidence of safety and efficacy for the intended use of a product candidate.

In light of widely publicized events concerning the safety of certain drug products, regulatory authorities, members of Congress, the Government Accountability Office, medical professionals and the general public have raised concerns about potential drug safety issues. These events have resulted in the withdrawal of certain drug products, revisions to certain drug labeling that further limit use of the drug products and establishment of risk management programs that may, for instance, restrict distribution of drug products. The increased attention to drug safety issues may result in a more cautious approach by the FDA to clinical trials and approval. Data from clinical trials may receive greater scrutiny with respect to safety and the product’s risk/benefit profile, which may make the FDA or other regulatory authorities more likely to terminate clinical trials before completion, or require longer or additional clinical trials that may result in substantial additional expense, and a delay or failure in obtaining approval or approval for a more limited indication than originally sought. Aside from issues concerning the quality and sufficiency of submitted preclinical and clinical data, the FDA may be constrained by limited resources from reviewing and determining the approvability of the Gencaro NDA by May 31, 2009. Indeed, in early 2008, the FDA announced that due to a lack of resources, NDAs may not be reviewed within the performance goals under PDUFA, and from time to time, the FDA has extended the review period for NDAs.

In addition, the manufacture and tableting of Gencaro is done by third party suppliers, who must pass a pre-approval inspection of their facilities before ARCA can obtain marketing approval. The FDA could also request additional information or data, including data from an additional Phase III study, which may extend the review period.

In its NDA, ARCA has requested that the FDA approve Gencaro as a therapy that can be prescribed by physicians for patients with heart failure, and specifically for its effect on certain clinical outcomes for these heart failure patients. ARCA has also requested that certain information be included in the prescribing information distributed with Gencaro that shows the effect of genetic differences in patients on the clinical results for Gencaro. The FDA could approve Gencaro, but without including some or all of the prescribing information that ARCA has requested. For instance, FDA could approve Gencaro without some or all of the pharmacogenetic information in the labeling. This, in turn, could substantially and detrimentally impact ARCA’s ability to successfully commercialize Gencaro and effectively protect its intellectual property rights in Gencaro.

ARCA has no manufacturing capacity which puts it at risk of lengthy and costly delays of bringing its products to market.

ARCA does not currently operate manufacturing facilities for clinical or commercial production of its product candidates, including their active pharmaceutical ingredients, or API. ARCA has no experience in drug formulation or manufacturing, and it lacks the resources and the capabilities to manufacture any of its product candidates on a clinical or commercial scale. ARCA does not intend to develop facilities for the manufacture of product candidates for clinical trials or commercial purposes in the foreseeable future.

ARCA has contracted with Groupe Novasep to manufacture commercial quantities of the API for Gencaro. For drug production, ARCA has contracted with Patheon, Inc. to manufacture the Gencaro tablets. In addition, ARCA is dependent upon other third-party contract manufacturers to develop the necessary production processes and produce the volume of cGMP-grade material needed to complete the anticipated Phase II study of NU172. These contract manufacturers may not perform as agreed or may not remain in the contract manufacturing business for the time required to successfully produce, store and distribute ARCA’s products. In the event of

errors in forecasting production quantities required to meet demand, natural disaster, equipment malfunctions or failures, technology malfunctions, strikes, lock-outs or work stoppages, regional power outages, product tampering, war or terrorist activities, actions of regulatory authorities, business failure, strike or other difficulty, ARCA may be unable to find an alternative third-party manufacturer in a timely manner and the production of its product candidates would be interrupted, resulting in delays and additional costs, which could impact ARCA’s ability to commercialize and sell its product candidates.

ARCA or its contract manufacturers may also fail to achieve and maintain required manufacturing standards, which could result in patient injury or death, product recalls or withdrawals, an order by governmental authorities to halt production, delays or failures in product testing or delivery, cost overruns or other problems that could seriously hurt its business. Contract manufacturers also often encounter difficulties involving production yields, quality control and quality assurance, as well as shortages of qualified personnel. In addition, its contract manufacturers are subject to ongoing inspections and regulation by the FDA, the U.S. Drug Enforcement Agency and corresponding state agencies and they may fail to meet these agencies’ acceptable standards of compliance. If ARCA’s contract manufacturers fail to comply with applicable governmental regulations, such as quality control, quality assurance and the maintenance of records and documentation, ARCA may not be able to continue production of the API or finished product. If the safety of any API or product supplied is compromised due to failure to adhere to applicable law or for other reasons, this may jeopardize ARCA’s regulatory approval for Gencaro and other product candidates, and ARCA may be held liable for any injuries sustained as a result.

Upon the occurrence of one of the aforementioned events, the ability to switch manufacturers may be difficult for a number of reasons, including:

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the number of potential manufacturers is limited and ARCA may not be able to negotiate agreements with alternative manufacturers on commercially reasonable terms, if at all;

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long lead times are often needed to manufacture drugs;

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the manufacturing process is complex and may require a significant learning curve; and

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the FDA must approve any replacement prior to manufacturing, which requires new testing and compliance inspections.

If ARCA’s product candidates receive regulatory approval, ARCA would be subject to ongoing regulatory obligations and restrictions, which may result in significant expenses and limit its ability to commercialize other potential products.

If a product candidate of ARCA is approved by the FDA or by another regulatory authority, ARCA would be held to extensive regulatory requirements over product manufacturing, testing, distribution, labeling, packaging, adverse event reporting and other reporting to regulatory authorities, storage, advertising, marketing, promotion, distribution, and record keeping. Regulatory approvals may also be subject to significant limitations on the indicated uses or marketing of the product candidates. Potentially costly follow-up or post-marketing clinical studies may be required as a condition of approval to further substantiate safety or efficacy, or to investigate specific issues of interest to the regulatory authority. Previously unknown problems with the product candidate, including adverse events of unanticipated severity or frequency, may result in additional regulatory controls or restrictions on the marketing or use of the product or the need for postmarketing studies, and could include suspension or withdrawal of the products from the market.

Furthermore, ARCA’s third-party manufacturers and the manufacturing facilities that they use to make ARCA’s product candidates are regulated by the FDA. Quality control and manufacturing procedures must continue to conform to cGMP after approval. Drug manufacturers and their subcontractors are required to register their facilities and products manufactured annually with the FDA and certain state agencies and are

subject to periodic unannounced inspections by the FDA, state and/or other foreign authorities. Any subsequent discovery of problems with a product, or a manufacturing or laboratory facility used by ARCA or its collaborators, may result in restrictions on the product, or on the manufacturing or laboratory facility, including a withdrawal of the drug from the market or suspension of manufacturing. Any changes to an approved product, including the way it is manufactured or promoted, often require FDA approval before the product, as modified, can be marketed. ARCA and its third-party manufacturers will also be subject to ongoing FDA requirements for submission of safety and other post-market information.

The marketing and advertising of ARCA’s drug products by its collaborators or ARCA will be regulated by the FDA, certain state agencies or foreign regulatory authorities. Violations of these laws and regulations, including promotion of ARCA’s products for unapproved uses or failing to disclose risk information, are punishable by criminal and civil sanctions and may result in the issuance of enforcement letters or other enforcement action by the FDA, U.S. Department of Justice, state agencies, or foreign regulatory authorities that could jeopardize ARCA’s ability to market the product.

In addition to the FDA, state or foreign regulations, the marketing of ARCA’s drug products by ARCA or its collaborators will be regulated by federal, state or foreign laws pertaining to health care “fraud and abuse,” such as the federal anti-kickback law prohibiting bribes, kickbacks or other remuneration for the order or recommendation of items or services reimbursed by federal health care programs. Many states have similar laws applicable to items or services reimbursed by commercial insurers. Violations of these laws are punishable by criminal and civil sanctions, including, in some instances, imprisonment and exclusion from participation in federal and state health care programs, including the Medicare, Medicaid and Veterans Affairs healthcare programs. Because of the far-reaching nature of these laws, ARCA may be required to discontinue one or more of its practices to be in compliance with these laws. Health care fraud and abuse regulations are complex, and even minor irregularities can potentially give rise to claims that a statute or prohibition has been violated. Any violations of these laws, or any action against ARCA for violations of these laws, even if ARCA successfully defends against it, could have a material adverse effect on ARCA’s business, financial condition and results of operations.

ARCA could also become subject to false claims litigation under federal statutes, which can lead to civil money penalties, restitution, criminal fines and imprisonment, and exclusion from participation in Medicare, Medicaid and other federal and state health care programs. These false claims statutes include the False Claims Act, which allows any person to bring a suit on behalf of the federal government alleging submission of false or fraudulent claims, or causing to present such false or fraudulent claims, under federal programs or contracts claims or other violations of the statute and to share in any amounts paid by the entity to the government in fines or settlement. These suits against pharmaceutical companies have increased significantly in volume and breadth in recent years. Some of these suits have been brought on the basis of certain sales practices promoting drug products for unapproved uses. This new growth in litigation has increased the risk that a pharmaceutical company will have to defend a false claim action, pay fines or restitution, or be excluded from the Medicare, Medicaid, Veterans Affairs and other federal and state healthcare programs as a result of an investigation arising out of such action. ARCA may become subject to such litigation and, if ARCA is not successful in defending against such actions, those actions may have a material adverse effect on its business, financial condition and results of operations. ARCA could also become subject to false claims litigation and consumer protection claims under state statutes, which also could lead to civil monetary penalties, restitution, criminal fines and imprisonment, and exclusion from participation in state health care programs.

Of note, over the past few years there has been an increased focus on the sales and marketing practices of the pharmaceutical industry at both the federal and state level. Additionally, the law or regulatory policies governing pharmaceuticals may change. New statutory requirements may be enacted or additional regulations may be enacted that could prevent or delay regulatory approval of ARCA’s product candidates. ARCA cannot predict the likelihood, nature or extent of adverse government regulation that may arise from future legislation or administrative action, either in the U.S. or elsewhere.

If ARCA, its collaborators or its third-party manufacturers fail to comply with applicable continuing regulatory requirements, ARCA’s business could be seriously harmed because a regulatory agency may:

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issue untitled or warning letters;

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suspend or withdraw ARCA’s regulatory approval for approved products;

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seize or detain products or recommend a product recall of a drug or medical device, or issue a mandatory recall of a medical device;

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refuse to approve pending applications or supplements to approved applications filed by ARCA;

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suspend any of ARCA’s ongoing clinical trials;

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impose restrictions on ARCA’s operations, including costly new manufacturing requirements, and restrictions on ARCA’s sales, marketing and/or distribution of ARCA’s products;

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seek an injunction;

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pursue criminal prosecutions;

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close the facilities of ARCA’s contract manufacturers; or

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impose civil or criminal penalties.

If LabCorp or certain of its third-party suppliers fail to comply with ongoing FDA or other foreign regulatory authority requirements, or if there are unanticipated problems with the Gencaro Test, these products could be subject to restrictions or withdrawal from the market.

Any medical device for which LabCorp obtains clearance or approval, and the manufacturing processes, reporting requirements, post-approval clinical data and promotional activities for such product, will be subject to continued regulatory review, oversight and periodic inspections by the FDA and other domestic and foreign regulatory bodies. With respect to the Gencaro Test, to the extent applicable, LabCorp and certain of its suppliers will be required to comply with the FDA’s Quality System Regulation, or QSR, and International Standards Organization, or ISO, requirements which cover the methods and documentation of the design, testing, production, control, quality assurance, labeling, packaging, storage and shipping of any product for which clearance or approval is obtained. Regulatory bodies, such as the FDA, enforce the QSR and other regulations through periodic inspections. The failure by LabCorp, or certain of its third-party manufacturers or suppliers, as the case may be, to comply with applicable statutes and regulations administered by the FDA and other regulatory bodies, or the failure to timely and adequately respond to any adverse inspectional observations or product safety issues, could result in, among other things, enforcement actions. If any of these actions were to occur, it could harm ARCA’s reputation and cause product sales and profitability of Gencaro to suffer and may prevent ARCA from generating revenue.

Even if regulatory clearance or approval is granted, such clearance or approval may be subject to limitations on the intended uses for which the product may be marketed and reduce ARCA’s potential to successfully commercialize the product and generate revenue from the product.

If LabCorp or certain of its third party suppliers fail to supply the Gencaro Test, the product sales and profitability of Gencaro will suffer.

LabCorp is ARCA’s single-source supplier of the Gencaro Test. If LabCorp or its third party suppliers were to cease or interrupt production of or otherwise fail to supply the Gencaro Test, or the materials required to produce it, in a timely manner or at all, ARCA could be unable to obtain a contract manufacturer of companion genetic test for Gencaro for an indeterminate period of time. This could adversely affect ARCA’s ability to satisfy demand for Gencaro, which could cause product sales and profitability of Gencaro to suffer and may have an adverse effect on the ARCA’s financial condition and results of operations.

Medical devices related to Gencaro, such as the Gencaro Test, may in the future be subject to product recalls that could harm ARCA’s reputation, business and financial results.

The FDA and similar foreign governmental authorities have the authority to require the recall of commercialized products in the event of material deficiencies or defects in design or manufacture. In the case of the FDA, the authority to require a mandatory recall must be based on an FDA finding that there is a reasonable probability that the device would cause serious adverse health consequences or death. In addition, foreign governmental bodies have the authority to require the recall of ARCA’s products in the event of material deficiencies or defects in design or manufacture. Manufacturers may, under their own initiative, initiate a field correction or removal, known as a recall, for a product if any material deficiency in a device is found. A government-mandated or voluntary recall by ARCA’s third-party suppliers, including LabCorp, could occur as a result of component failures, manufacturing errors, design or labeling defects or other deficiencies and issues. Any such recalls would divert managerial and financial resources and may have an adverse effect on the ARCA’s financial condition and results of operations.

If medical devices related to Gencaro, such as the Gencaro Test, cause or contribute to a death or a serious injury, or malfunction in certain ways, ARCA’s third-party suppliers will be subject to medical device reporting regulations, which can result in voluntary corrective actions or agency enforcement actions.

Under the FDA’s medical device reporting regulations, medical device manufacturers are required to report to the FDA information that a device has or may have caused or contributed to a death or serious injury or has malfunctioned in a way that would likely cause or contribute to death or serious injury if the malfunction of the device or one of ARCA’s similar devices were to recur. If ARCA’s third-party suppliers, including LabCorp, fail to report these events to the FDA within the required timeframes, or at all, the FDA could take enforcement action against ARCA’s third-party suppliers, including LabCorp. Any such adverse event involving the Gencaro Test also could result in future voluntary corrective actions, such as recalls or customer notifications, or agency action, such as inspection or enforcement action. Any corrective action, whether voluntary or involuntary, taken by ARCA’s third-party suppliers, including LabCorp, may significantly affect ARCA’s ability to market Gencaro. In such cases, ARCA could be forced to identify a new third-party test provider for the Gencaro Test.

LabCorp may need to conduct clinical trials to support current or future versions of the Gencaro Test. Delays or failures in any such clinical trials may prevent LabCorp from commercializing any modified or new versions of the Gencaro Test and will adversely affect ARCA’s business, operating results and prospects.

Based on discussions with the FDA, ARCA and LabCorp do not believe that clinical data are needed for the Gencaro Test submission. However, the FDA may require clinical data for the Gencaro Test submission and/or future products. Initiating and completing clinical trials necessary to support 510(k)s or PMAs, if required, for current or future products will be time consuming and expensive and the outcome uncertain. Moreover, the results of early clinical trials are not necessarily predictive of future results, and any product ARCA or its third party suppliers, including LabCorp, advance into clinical trials may not have favorable results in later clinical trials.

Conducting successful clinical studies may require the enrollment of large numbers of patients, and suitable patients may be difficult to identify and recruit. Patient enrollment in clinical trials and completion of patient participation and follow-up depends on many factors, including: the size of the patient population; the number of patients to be enrolled; the nature of the trial protocol; the attractiveness of, or the discomforts and risks associated with, the treatments received by enrolled subjects; the availability of appropriate clinical trial investigators, support staff, and proximity of patients to clinical sites; and the patients’ ability to meet the eligibility and exclusion criteria for participation in the clinical trial and patient compliance. For example, patients may be discouraged from enrolling in clinical trials if the trial protocol requires them to undergo extensive post-treatment procedures or follow-up to assess the safety and effectiveness of ARCA’s products or if they determine that the treatments received under the trial protocols are not attractive or involve unacceptable

risks or discomforts. In addition, patients participating in clinical trials may die before completion of the trial or suffer adverse medical events unrelated to investigational products.

Development of sufficient and appropriate clinical protocols to demonstrate safety and efficacy are required, and LabCorp, or ARCA may not adequately develop such protocols to support clearance and approval. Significant risk trials will require the submission and approval of an investigational device exemption, or IDE, from the FDA. There is no guarantee that the FDA will approve LabCorp’s or ARCA’s future IDE submissions. Further, the FDA may require LabCorp or ARCA to submit data on a greater number of patients than originally anticipated and/or for a longer follow-up period or change the data collection requirements or data analysis applicable to ARCA’s clinical trials. Delays in patient enrollment or failure of patients to continue to participate in a clinical trial may cause an increase in costs and delays in the approval and attempted commercialization of future products or result in the failure of the clinical trial. In addition, despite considerable time and expense invested in such clinical trials, the FDA may not consider the data to be adequate to demonstrate safety and efficacy. Such increased costs and delays or failures could adversely affect ARCA’s third party suppliers’, or ARCA’s business, operating results and prospects.

Federal regulatory reforms may adversely affect ARCA’s or its suppliers’ ability to sell products profitably.

From time to time, legislation is drafted and introduced in the U.S. Congress that could significantly change the statutory provisions governing the clearance or approval, manufacture and marketing of a medical device. In addition, FDA regulations and guidance are often revised or reinterpreted by the agency in ways that may significantly affect the way that medical devices are marketed and promoted. It is impossible to predict whether legislative changes will be enacted or FDA regulations, guidance or interpretations changed, and what the impact of such changes, if any, may be.

Without limiting the generality of the foregoing, in September 2007, the Food and Drug Administration Amendments Act of 2007, or the Amendments, were enacted. The Amendments require, among other things, that the FDA propose, and ultimately implement, regulations that will require manufacturers to label medical devices with unique identifiers unless a waiver is received from the FDA. Once implemented, compliance with those regulations may require manufacturers to take additional steps in the manufacture and labeling of medical devices. These steps may require additional resources and could be costly. In addition, the Amendments require medical device manufacturers to, among other things, comply with clinical trial registration requirements once clinical trials are initiated.

ARCA’s failure to establish and manage a distribution network for its products could delay or compromise the commercialization of Gencaro and other future products.

ARCA has not yet established systems and processes necessary for distributing products to customers. ARCA plans to contract with one or more wholesale distributors to warehouse its products and distribute them to retail, hospital and other pharmacy suppliers that would then distribute its products directly to patients. This distribution network will require significant coordination with its sales and marketing and finance organizations. Failure to secure contracts with distribution services could negatively impact the distribution of ARCA’s products, if any, and failure to coordinate financial systems could negatively impact its ability to accurately report product revenue, if any. If ARCA is unable to effectively establish and manage the distribution process, then the commercialization of Gencaro and other product candidates may be delayed or severely compromised and ARCA’s results of operations may be harmed.

If approved by the FDA, Gencaro will be entering into a competitive marketplace and may not succeed.

Gencaro is a new type of beta-blocker and vasodilator being developed for heart failure and other indications. While ARCA anticipates that this drug will be the first genetically-targeted cardiovascular drug, Gencaro will be one of a number of successful drugs in the beta-blocker class currently on the market. Currently,

there are three branded beta-blockers indicated for chronic heart failure in New York Health Association, or NYHA class II-IV patients: TOPROL-XL (once-a-day formulation), Coreg and Coreg CR (once-a-day). TOPROL-XL and Coreg have generic equivalents commercially available in the U.S. (Metoprolol Succinate and Carvedilol, respectively). The price of the generic forms of these drugs will be less than the anticipated price of Gencaro, if approved. As a result, Gencaro may not be successful in competing against these existing drugs.

Additionally, Forest Laboratories may apply for approval to use Bystolic, a drug currently used to treat high blood pressure, for treatment of heart failure. If approved for treatment of heart failure, Gencaro may not be successful in competing against Bystolic, an already well-known name brand. Accordingly, ARCA may not achieve its revenue goals, and its business may be harmed.

ARCA’s commercial opportunity may be reduced or eliminated if competitors develop and commercialize products that are safer, more effective, have fewer side effects, are more convenient or are less expensive than Gencaro. If products with any of these properties are developed, or any of the existing products are better marketed, then prescriptions of Gencaro by physicians and patient use of Gencaro could be significantly reduced or rendered obsolete and noncompetitive. Further, public announcements regarding the development of any such competing drugs could adversely affect the market price of ARCA’s common stock.

Future sales of ARCA’s products may suffer if they are not accepted in the marketplace by physicians, patients and the medical community.

Gencaro or ARCA’s other product candidates may not gain market acceptance among physicians, patients and the medical community. The degree of market acceptance of Gencaro or ARCA’s other product candidates will depend on a number of factors, such as its effectiveness and tolerability, as compared with competitive drugs. Also, prevalence and severity of side-effects could negatively affect market acceptance of Gencaro or ARCA’s other product candidates. For example, side-effects of Gencaro observed during clinical trials included fatigue, dizziness and slowed heart beat. Failure to achieve market acceptance of Gencaro would significantly harm ARCA’s business.

If ARCA is unable to obtain acceptable prices or adequate reimbursement from third-party payors for Gencaro, or any other product candidates that ARCA may seek to commercialize, then its revenues and prospects for profitability will suffer.

ARCA’s ability to commercialize Gencaro, or any other product candidates that it may seek to commercialize, is highly dependent on the extent to which coverage and reimbursement for these product candidates will be available from:

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governmental payors, such as Medicare and Medicaid;

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private health insurers, including managed-care organizations; and

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other third-party payors.

Many patients will not be capable of paying for ARCA’s potential products themselves and will rely on third-party payors to pay for their medical needs. A primary current trend in the U.S. health care industry is toward cost containment. Large private payors, managed-care organizations, group purchasing organizations and similar organizations are exerting increasing influence on decisions regarding the use of, and reimbursement levels for, particular treatments. Such third-party payors, including Medicare, are challenging the prices charged for medical products and services, and many third-party payors limit reimbursement for newly approved health care products. In particular, third-party payors may limit the reimbursed indications.

Cost-control initiatives could decrease the price ARCA might establish for products, which could result in product revenues lower than anticipated. If the prices for ARCA’s product candidates decrease or if

governmental and other third-party payors do not provide adequate coverage and reimbursement levels, then ARCA’s revenue and prospects for profitability will suffer.

ARCA’s competitors may be better positioned in the marketplace and thereby may be more successful than ARCA at developing, manufacturing and marketing approved products.

Many of ARCA’s competitors currently have significantly greater financial resources and expertise in conducting clinical trials, obtaining regulatory approvals, managing manufacturing and marketing approved products than ARCA. Other early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. In addition, these third parties compete with ARCA in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring therapies and therapy licenses complementary to ARCA’s programs or advantageous to its business. ARCA expects that its ability to compete effectively will depend upon its ability to:

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successfully and rapidly complete clinical trials for any future product candidates and obtain all requisite regulatory approvals in a cost-effective manner;

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build an adequate sales and marketing infrastructure;

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develop competitive formulations of its product candidates;

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attract and retain key personnel; and

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identify and obtain other product candidates on commercially reasonable terms.

If ARCA fails to identify and license or acquire other products or product candidates, then it may be unable to expand its business, and the acquisition or licensing of other products or product candidates may put a strain on ARCA’s operations and will likely require ARCA to seek additional financing.

One of ARCA’s key strategies is to license or acquire clinical-stage products or product candidates and further develop them for commercialization. The market for licensing and acquiring products and product candidates is intensely competitive and many of ARCA’s competitors may have greater resources than ARCA. If ARCA undertakes any additional acquisitions, whether of product candidates or other biopharmaceutical companies, the process of integrating an acquired product, candidate or complementary company into ARCA’s business may put a strain on its operations, divert personnel, financial resources and management’s attention. If ARCA is not successful in identifying and licensing or acquiring other products or product candidates or completing future acquisitions, then it may be unable expand its pipeline of product candidates. In addition, any future acquisition would give rise to additional operating costs and will likely require ARCA to seek additional financing. Future acquisitions could result in additional issuances of equity securities that would dilute the ownership of existing stockholders. Future acquisitions could also result in the incurrence of debt, contingent liabilities or the amortization of expenses related to other intangible assets, any of which could adversely affect ARCA’s operating results.

Any future product revenues could be reduced by imports from countries where ARCA’s product candidates are available at lower prices.

Even if ARCA obtains FDA approval to market Gencaro or other products in the U.S., ARCA’s sales in the U.S. may be reduced if ARCA’s products are imported into the U.S. from lower priced markets, whether legally or illegally. In the U.S., prices for pharmaceuticals are generally higher than in the bordering nations of Canada and Mexico. There have been proposals to legalize the import of pharmaceuticals from outside the U.S. If such legislation were enacted, then ARCA’s future revenues could be reduced.

If ARCA encounters difficulties enrolling patients in its clinical trials, its trials could be delayed or otherwise adversely affected.

Clinical trials for ARCA’s product candidates require that ARCA identify and enroll a large number of patients with the disorder or condition under investigation. ARCA may not be able to enroll a sufficient number of patients to complete its clinical trials in a timely manner.

Patient enrollment is affected by factors including:

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design of the protocol;

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the size of the patient population;

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eligibility criteria for the study in question;

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perceived risks and benefits of the drug under study;

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availability of competing therapies, including the off-label use of therapies approved for related indications;

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efforts to facilitate timely enrollment in clinical trials;

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the success of ARCA’s personnel in making the arrangements with potential clinical trial sites necessary for those sites to begin enrolling patients;

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patient referral practices of physicians;

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availability of clinical trial sites; and

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other clinical trials seeking to enroll subjects with similar profiles.

If ARCA has difficulty enrolling a sufficient number of patients to conduct its clinical trials as planned, ARCA may need to delay or terminate ongoing or planned clinical trials, either of which would have a negative effect on its business. Delays in enrolling patients in ARCA’s clinical trials would also adversely affect its ability to generate product, milestone and royalty revenues and could impose significant additional costs on ARCA or on its collaborators.

ARCA’s clinical trials for its product candidates may not yield results that will enable ARCA to further develop its products and obtain the regulatory approvals necessary to sell them.

ARCA, and its collaborators, will only receive regulatory approval for its product candidates if ARCA can demonstrate in carefully designed and conducted clinical trials that the product candidate is safe and effective. ARCA does not know whether its current or any future clinical trials will demonstrate sufficient safety and efficacy to obtain the requisite regulatory approvals or will result in marketable products. Clinical trials are lengthy, complex and expensive processes with uncertain results. ARCA has spent, and expects to continue to spend, significant amounts of time and money in the clinical development of its product candidates.

The results ARCA obtains in preclinical testing and early clinical trials may not be predictive of results that are obtained in later studies. ARCA may suffer significant setbacks in advanced clinical trials, even after promising results in earlier studies. Based on results at any stage of clinical trials, ARCA may decide to repeat or redesign a trial or discontinue development of one or more of ARCA’s product candidates. If ARCA fails to adequately demonstrate the safety and efficacy of its products under development, ARCA will not be able to obtain the required regulatory approvals to commercialize ARCA’s product candidates, and its business, results of operations and financial condition would be materially adversely affected.

Administering ARCA’s product candidates to humans may produce undesirable side effects. These side effects could interrupt, delay or halt clinical trials of ARCA’s product candidates and could result in the FDA or other regulatory authorities denying approval of its product candidates for any or all targeted indications.

If clinical trials for a product candidate are unsuccessful, ARCA will be unable to commercialize the product candidate. If one or more of ARCA’s clinical trials are delayed, it will be unable to meet its anticipated development timelines. Either circumstance could cause the market price of ARCA’s common stock to decline.

ARCA may not achieve its projected development goals in the time frames it announces and expects.

ARCA sets goals for, and makes public statements regarding, the timing of certain accomplishments, such as the commencement and completion of clinical trials, the disclosure of trial results, the obtaining of regulatory approval and drug product sales, which ARCA sometimes refers to as milestones. These milestones may not be achieved, and the actual timing of these events can vary dramatically due to a number of factors such as delays or failures in ARCA’s clinical trials, disagreements with current or future collaborative partners, the uncertainties inherent in the regulatory approval process and manufacturing scale-up and delays in achieving manufacturing or marketing arrangements sufficient to commercialize ARCA’s products. There can be no assurance that ARCA’s clinical trials will be completed, or that it will make regulatory submissions or receive regulatory approvals as planned. If ARCA fails to achieve one or more of these milestones as planned, its business will be materially adversely affected, and the price of ARCA’s shares will decline.

ARCA would be subject to applicable regulatory approval requirements of the foreign countries in which ARCA markets its products, which are costly and may prevent or delay ARCA from marketing its products in those countries.

In addition to regulatory requirements in the United States, ARCA would subject to the regulatory approval requirements in each foreign country where it markets its products. In addition, ARCA might be required to identify one or more collaborators in these foreign countries to develop, seek approval for and manufacture it products and any companion genetic test for Gencaro. If ARCA determines to pursue regulatory approvals and commercialization of its product candidates internationally, it may not be able to obtain the required foreign regulatory approvals on a timely basis, if at all, and any failure to do so may cause ARCA to incur additional costs or prevent ARCA from marketing its products in foreign countries, which may have a material adverse effect on ARCA’s business, financial condition and results of operations.

If ARCA cannot successfully integrate the Nuvelo organization, ARCA may not be able to operate efficiently after the merger or to realize any benefits from the merger.

Achieving the benefits of the merger will depend in part on the successful integration of ARCA’s and Nuvelo’s technical and business operations and remaining personnel in a timely and efficient manner. The integration process requires coordination of the personnel of both companies, involves the integration of systems, applications, policies, procedures, business processes and operations and is a complex, costly and time-consuming process. The difficulties of combining the operations of the companies include, among others:

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consolidating research and development operations;

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retaining key employees;

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consolidating corporate and administrative infrastructures;

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preserving the research and development and other important relationships of the companies;

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integrating and managing the technology of two companies;

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using the combined company’s liquid capital and other assets efficiently to develop the business of the combined company;

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appropriately managing the liabilities of the combined company;

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diverting management’s attention from ongoing business concerns; and

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coordinating geographically separate organizations.

ARCA cannot assure you that it will receive any benefits of this or any other merger or acquisitions, or that any of the difficulties described above will not adversely affect the Company. The integration process may be difficult and unpredictable because of possible conflicts and differing opinions on business, scientific and regulatory matters. If the companies cannot successfully integrate their technical and business operations and personnel, ARCA may not realize the expected benefits of the merger.

ARCA expects to incur significant costs integrating the companies into a single business.

ARCA expects to incur significant costs integrating the technical and business operations and personnel of Nuvelo and ARCA, which may include costs for employee redeployment, relocation or severance, conversion of information systems, reorganization of facilities, disposition of excess facilities and relocation or disposition of excess equipment. The benefits of the merger may not be sufficient to justify these integration costs.

Integrating the companies may divert the attention of ARCA’s management away from its operations.

ARCA’s successful integration of Nuvelo’s technical and business operations and personnel into its own organization may place a significant burden on ARCA’s management and internal resources. The diversion of management’s attention and any difficulties encountered in the transition and integration process could result in delays in ARCA’s clinical trial and product development programs and could otherwise harm ARCA’s business, financial condition and operating results.

ARCA has incurred and will continue to incur increased costs as a result of being a public company.

As a public company, ARCA has incurred and will continue to incur significant levels of legal, accounting and other expenses. The Sarbanes-Oxley Act of 2002, or the Sarbanes-Oxley Act, and related rules of the SEC and Nasdaq regulate corporate governance practices of public companies and impose significant requirements relating to disclosure controls and procedures and internal control over financial reporting. Compliance with these public company requirements has increased ARCA’s costs, required additional resources and made some activities more time consuming. ARCA is required to expend considerable time and resources complying with public company regulations.

Failure to establish and maintain effective internal control over financial reporting could have a material adverse effect on ARCA’s business, operating results and stock price.

Maintaining effective internal control over financial reporting is necessary for ARCA to produce reliable financial reports and is important in helping to prevent financial fraud. Prior to the recently completed merger involving Nuvelo, ARCA was not subject to the Sarbanes-Oxley Act. Therefore, ARCA’s management only performed an evaluation of Nuvelo’s internal control over financial reporting as of December 31, 2008 in accordance with the provisions of the Sarbanes-Oxley Act. Material weaknesses may exist when ARCA reports on the effectiveness of its internal control over financial reporting for purposes of its reporting requirements under the Exchange Act or Section 404 of the Sarbanes-Oxley Act for ARCA’s fiscal year ending December 31, 2009. The existence of one or more material weaknesses would preclude a conclusion that ARCA maintains effective internal control over financial reporting. Such a conclusion would be required to be disclosed in ARCA’s future Annual Reports on Form 10-K and could impact the accuracy and timing of its financial reporting and the reliability of its internal control over financial reporting, which could harm ARCA’s reputation and cause the market price of its common stock to drop.

ARCA’s investments in marketable debt securities are subject to credit risk that may adversely affect their fair value.

ARCA maintains a significant portfolio of investments in marketable debt securities, which are recorded at fair value. To minimize ARCA’s exposure to credit risk, ARCA invests in securities with strong credit ratings

and has established guidelines relative to diversification and maturity with the objective of maintaining safety of principal and liquidity. ARCA does not invest in derivative financial instruments, mortgage-backed securities or auction rate securities, and ARCA has not recorded any losses on ARCA’s securities due to credit or liquidity issues. Since 2007, rising delinquency and default rates on subprime mortgages and declining home prices have caused a significant decline in the value of residential mortgage-backed securities, which has negatively impacted the entire credit market in the U.S. In recent months, certain other financial instruments have also sustained downgrades in credit ratings and declines in value. Further deterioration in the credit market may have an adverse effect on the fair value of ARCA’s investment portfolio.

The continued economic downturn could adversely affect our business and operating results.

The U.S. economy was in a recession through much or all of 2008, which has continued and deepened in 2009. As the global financial crisis has broadened and intensified, a severe recession appears likely. Business activity across a wide range of industries and regions is substantially reduced, and many companies are in serious difficulty due to the lack of consumer spending, reduced access to credit, cash flow shortages, deterioration of their businesses and lack of liquidity in the capital markets. Challenging economic and market conditions may also result in:

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reductions to our workforce;

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increased price competition, which may adversely affect the revenue and gross margins we anticipate from any of our product candidates, once commercialized;

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financial strain on the health care system, which may lead to lower than anticipated sales of our product candidates, once commercialized;

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the bankruptcy or insolvency of our collaborators and third party manufacturers; and

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difficulties in forecasting, budgeting and planning due to limited visibility into economic conditions.

A prolonged national or regional economic recession, or other events that have produced or could produce major changes economic patterns, such as the housing market crisis, the credit crisis or a terrorist attack, could have a material adverse effect on our business, results of operations and financial condition.

Risks Related to ARCA’s Capital Structure and Stock Price Volatility

ARCA is evaluating whether and when to raise additional funds through the public or private debt and equity markets.

ARCA believes that its current cash, cash equivalents and marketable securities balances are sufficient to fund operations through at least December 31, 2009. However, because of ARCA’s substantial capital requirements necessary to fund commercialization of Gencaro, if approved, ARCA will seek to access the public or private debt and equity markets. Additional funding may not be available to ARCA, and, if available, may not be on acceptable terms.

ARCA’s future capital requirements depend on a number of factors, including, but not limited to, the following:

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timing and outcomes of regulatory approvals, in particular the approval of ARCA’s NDA for Gencaro by the FDA;

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the costs of commercializing ARCA’s product candidates once regulatory approvals are obtained, including the costs of establishing or contracting for marketing, sales and manufacturing capabilities, and other costs related to increasing the size of ARCA’s organization;

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the extent to which ARCA is able to acquire or in-license new products, technologies or businesses;

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the costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; and

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the terms and timing of any additional collaborative, strategic partnership or licensing agreements that ARCA may establish.

If ARCA’s available cash and cash equivalents and funding received or made available are insufficient to satisfy its liquidity requirements, or if ARCA develops additional products or pursues additional applications for its products or conducts additional clinical trials beyond those currently contemplated, ARCA may seek to sell additional equity or incur additional indebtedness. The sale of additional equity or convertible debt securities may result in additional dilution to ARCA’s stockholders. If ARCA raises additional funds through the incurrence of additional indebtedness, the obligations related to such indebtedness would be senior to rights of holders of ARCA capital stock and could contain covenants that would restrict ARCA’s operations. Any required additional funds may not be available on reasonable terms, if at all. If ARCA is unable to obtain additional financing, it may be required to modify or limit its planned research, development and commercialization strategies, which could adversely affect its business.

Continued disruption in financial markets may affect ARCA’s ability to access sufficient funding.

The global financial crisis and the broad domestic economic downturn have disrupted credit and equity markets globally, which has reduced the availability of investment capital and credit. A continuation or worsening of these conditions may make it difficult or impossible for us to refinance our indebtedness and access adequate funding to raise additional capital if needed, and may otherwise have a material adverse effect on our liquidity and capital resources.

ARCA may be limited in its ability to access sufficient funding through a private equity or convertible debt offering.

Nasdaq rules impose restrictions on ARCA’s ability to raise funds through a private offering of ARCA’s common stock, convertible debt or similar instruments without obtaining stockholder approval. Under Nasdaq rules, an offering of more than 20% of ARCA’s total shares outstanding for less than the greater of book or market value requires stockholder approval unless the offering qualifies as a “public offering” for purposes of the Nasdaq rules. As of March 17, 2009, ARCA had 7,567,399 shares of common stock outstanding, 20% of which is approximately 1,513,479 shares. If ARCA were to seek to raise funds through a private offering of stock, convertible debt or similar instruments, it would be limited in how much funding it could raise privately without requiring a stockholder vote and may instead be required to raise funding through a more costly public offering of its securities.

Ownership of ARCA’s common stock is highly concentrated, and it may prevent you and other stockholders from influencing significant corporate decisions and may result in conflicts of interest that could cause ARCA’s stock price to decline.

ARCA’s executive officers, directors and their affiliates beneficially own approximately 49% of the outstanding common stock of ARCA as of January 27, 2009. Accordingly, these executive officers, directors and their affiliates, acting individually or as a group, have substantial influence over the outcome of a corporate action of ARCA requiring stockholder approval, including the election of directors, any merger, consolidation or sale of all or substantially all of ARCA’s assets or any other significant corporate transaction. These stockholders may also delay or prevent a change in control of ARCA, even if such change in control would benefit the other stockholders of ARCA. The significant concentration of stock ownership may adversely affect the value of ARCA’s common stock due to investors’ perception that conflicts of interest may exist or arise.

ARCA’s stock price is expected to be volatile.

ARCA’s common stock could be subject to significant fluctuations. Market prices for securities of early-stage pharmaceutical, biotechnology and other life sciences companies have historically been particularly volatile. Some of the factors that may cause the market price of ARCA’s common stock to fluctuate include:

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the regulatory status of Gencaro and the Gencaro Test, and whether and when they are approved for sale, if at all, and the labeling or other conditions of use imposed by the FDA;

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the results of ARCA’s future clinical trials and any future NDAs of its current and future product candidates;

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the entry into, or termination of, key agreements, including key strategic alliance agreements;

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the results and timing of regulatory reviews relating to the approval of ARCA’s product candidates;

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failure of any of ARCA’s product candidates, if approved, to achieve commercial success;

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general and industry-specific economic conditions that may affect ARCA’s research and development expenditures;

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the results of clinical trials conducted by others on drugs that would compete with ARCA’s product candidates;

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issues in manufacturing ARCA’s product candidates or any approved products;

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the initiation of material developments in or the conclusion of litigation to enforce or defend any of the ARCA’s intellectual property rights;

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the loss of key employees;

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the introduction of technological innovations or new commercial products by competitors of ARCA;

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changes in estimates or recommendations by securities analysts, if any, who cover ARCA’s common stock;

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future sales of ARCA’s common stock;

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changes in the structure of health care payment systems; and

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period-to-period fluctuations in ARCA’s financial results.

Moreover, the stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of individual companies. These broad market fluctuations may also adversely affect the trading price of ARCA’s common stock.

In the past, following periods of volatility in the market price of a company’s securities, stockholders have often instituted class action securities litigation against those companies. Such litigation, if instituted, could result in substantial costs and diversion of management attention and resources, which could significantly harm ARCA’s profitability and reputation.

Our existing indebtedness could adversely affect our financial condition, prevent us from fulfilling our financial obligations and limit our ability to obtain additional investment capital and credit.

ARCA’s subsidiary, ARCA biopharma Colorado, Inc., or ARCA Colorado, is a party to a Loan and Security Agreement dated July 17, 2007, as amended January 21, 2009, with Silicon Valley Bank, or SVB, under which SVB provided a growth capital facility of up to $4.0 million dollars, to be used solely for working capital and to fund ARCA’s general business requirements. As of March 2, 2009, approximately $3.5 million aggregate principal amount was outstanding under the SVB credit facility. No additional drawings are permitted under the credit facility. The credit facility is not subject to any prepayment penalties. All borrowings under this agreement bear interest at a floating per annum rate equal to SVB’s prime rate, which was 4.0% as of March 2, 2009.

The agreement contains customary affirmative and negative covenants including, without limitation, (i) covenants requiring ARCA Colorado to comply with applicable laws, provide to SVB copies of ARCA’s financial statements, maintain appropriate levels of insurance, protect, defend and maintain the validity and enforceability of ARCA Colorado’s material intellectual property, and (ii) covenants restricting ARCA Colorado’s ability to dispose of all or substantially all of its assets, engage in other lines of business, change its senior management, enter into transactions constituting a change of control, assume additional indebtedness, incur liens on its assets, among other covenants. ARCA Colorado’s obligations under the credit facilities are secured by all of ARCA Colorado’s assets.

This indebtedness could have important consequences to you. For example, it could:

•

make it more difficult to satisfy our financial obligations to third parties other than SVB;

•

increase our vulnerability to adverse economic and industry conditions;

•

require us to dedicate a substantial portion of our cash to debt service, thereby reducing the availability of our cash to fund acquisitions, working capital, capital expenditures, research and development efforts and other general corporate purposes;

•

limit our flexibility in planning for, or reacting to, changes in our business and the industry in which we operate;

•

place us at a competitive disadvantage compared to our competitors that have less or no debt;

•

limit our ability to borrow additional funds; and

•

limit our ability to make future acquisitions.

The SVB credit facility was to mature on March 23, 2009, but ARCA and SVB are in discussions to refinance the existing credit facility and extend the credit facility’s maturity date until December 1, 2010. Pending the execution and delivery of definitive documentation reflecting the refinancing of the credit facility, SVB has agreed to extend the maturity date of the credit facility until April 6, 2009. We may not be able to refinance the existing SVB credit facility on commercially reasonable terms or at all.

Future sales or the possibility of future sales of ARCA’s common stock may depress the market price of ARCA’s common stock.

Sales in the public market of substantial amounts of ARCA’s common stock could depress prevailing market prices of its common stock. As of March 17, 2009, ARCA had 7,567,399 shares of common stock outstanding. All of these shares are freely transferable without restriction or further registration under the Securities Act, except for shares held by ARCA’s directors, officers and other affiliates and unregistered shares held by non-affiliates. Although ARCA does not believe that its directors, officers and other affiliates have any present intentions to dispose of large amounts of any shares of common stock owned by them, there can be no assurance that such intentions will not change in the future. The sale of these additional shares could depress the market price of ARCA’s common stock.

As of March 17, 2009, ARCA had approximately 1.1 million shares of ARCA’s common stock which may be issued upon exercise of outstanding stock options. If and when these options are exercised, such shares are available for sale in the open market without further registration under the Securities Act. The existence of these outstanding options may negatively affect ARCA’s ability to complete future equity financings at acceptable prices and on acceptable terms. The exercise of those options, and the prompt resale of shares of ARCA’s common stock received, may also result in downward pressure on the price of ARCA’s common stock.

As of March 17, 2009, approximately 210,000 shares of ARCA’s common stock were issuable upon the exercise of outstanding warrants, which were all exercisable as of this date. Once a warrant is exercised, if the shares of ARCA common stock issued upon the exercise of any such warrant are not available for sale in the open market without further registration under the Securities Act, then the holder can arrange for the resale of shares either by invoking any applicable registration rights, causing the shares to be registered under the Securities Act and thus freely transferable, or by relying on an exemption to the Securities Act. If these registration rights, or similar registration rights that may apply to securities ARCA may issue in the future, are exercised, it could result in additional sales of ARCA’s common stock in the market, which may have an adverse effect on ARCA’s stock price.

ARCA may need to raise significant additional capital to finance its capital requirements, including the research, development and commercialization of its drug products. If future securities offerings are successful, they could dilute ARCA’s current stockholders’ equity interests and reduce the market price of its common stock.

ARCA does not expect to pay cash dividends, and accordingly, stockholders must rely on stock appreciation for any return on their investment.

ARCA anticipates that it will retain its earnings, if any, for future growth and therefore does not anticipate paying cash dividends in the future. As a result, only appreciation of the price of its common stock will provide a return to stockholders. Investors seeking cash dividends should not invest in its common stock.

ARCA has implemented anti-takeover provisions that could discourage, prevent or delay a takeover, even if the acquisition would be beneficial to ARCA’s stockholders.

Provisions of ARCA’s certificate of incorporation and bylaws, as well as provisions of Delaware law, could make it more difficult for a third party to acquire ARCA, even if doing so would benefit ARCA’s stockholders. These provisions:

•

establish a classified board of directors so that not all members of ARCA’s board may be elected at one time;

•

authorize the issuance of up to 5 million additional shares of preferred stock that could be issued by ARCA’s board of directors to increase the number of outstanding shares and hinder a takeover attempt;

•

limit who may call a special meeting of stockholders;

•

prohibit stockholder action by written consent, thereby requiring all stockholder actions to be taken at a meeting of ARCA’s stockholders; and

•

establish advance notice requirements for nominations for election to ARCA’s board of directors or for proposing matters that can be acted upon at a stockholder meeting.

Specifically, ARCA’s certificate of incorporation provides that all stockholder action must be effected at a duly called meeting and not by a written consent. The bylaws provide, however, that ARCA’s stockholders may call a special meeting of stockholders only upon a request of stockholders owning at least 50% of ARCA’s common stock. These provisions of ARCA’s certificate of incorporation and bylaws could discourage potential acquisition proposals and could delay or prevent a change in control. ARCA designed these provisions to reduce ARCA’s vulnerability to unsolicited acquisition proposals and to discourage certain tactics that may be used in proxy fights. These provisions, however, could also have the effect of discouraging others from making tender offers for ARCA’s shares. As a consequence, they also may inhibit fluctuations in the market price of ARCA’s shares that could result from actual or rumored takeover attempts. Such provisions also may have the effect of preventing changes in ARCA’s management.

ARCA is permitted to issue shares of ARCA’s preferred stock without stockholder approval upon such terms as ARCA’s board of directors determines. Therefore, the rights of the holders of ARCA’s common stock are subject to, and may be adversely affected by, the rights of the holders of ARCA’s preferred stock that may be issued in the future. In addition, the issuance of preferred stock could have a dilutive effect on the holdings of ARCA’s current stockholders.

ARCA is subject to the Delaware anti-takeover laws regulating corporate takeovers. These anti-takeover laws prevent a Delaware corporation from engaging in a merger or sale of more than 10% of its assets with any stockholder, including all affiliates and associates of the stockholder, who owns 15% or more of the corporation’s outstanding voting stock, for six years following the date that the stockholder acquired 15% or more of the corporation’s stock unless:

•

the board of directors approved the transaction where the stockholder acquired 15% or more of the corporation’s stock;

•

after the transaction in which the stockholder acquired 15% or more of the corporation’s stock, the stockholder owned at least 85% of the corporation’s outstanding voting stock, excluding shares owned by directors, officers and employee stock plans in which employee participants do not have the right to determine confidentially whether shares held under the plan will be tendered in a tender or exchange offer; or

•

on or after this date, the merger or sale is approved by the board of directors and the holders of at least two-thirds of the outstanding voting stock that is not owned by the stockholder.

The provisions of ARCA’s governing documents and current Delaware law may, collectively:

•

lengthen the time required for a person or entity to acquire control of ARCA through a proxy contest for the election of a majority of ARCA’s board of directors;

•

discourage bids for ARCA’s common stock at a premium over market price; and

•

generally deter efforts to obtain control of ARCA.

Risks Related to Intellectual Property and Other Legal Matters

ARCA is party to securities litigation, and defending these lawsuits could hurt ARCA’s business. The volatility of the market price could engender additional class action securities litigation.

Following periods of volatility in the market price of a company’s securities, class action securities litigation has often been instituted against such a company. This risk is especially acute for biotechnology companies, which have experienced greater than average stock price volatility in recent years and, as a result, have been subject to, on average, a greater number of securities class action claims than companies in other industries. Any such litigation instigated against ARCA could result in substantial costs and a diversion of management’s attention and resources, which could significantly harm ARCA’s business, financial condition and operating results.

For example, in December 2006, after Nuvelo announced that alfimeprase did not meet its primary endpoint in the first of two planned Phase III trials for the treatment of acute peripheral arterial occlusion and in the first of two planned Phase III trials for the treatment of catheter occlusion, the closing price of one share of Nuvelo’s common stock was $81 (as adjusted for the 20-to-1 reverse stock split) on the day of the announcement, as compared with a closing price of $391 (as adjusted for the 20-to-1 reverse stock split) on the trading day prior to the announcement. On February 9, 2007, Nuvelo and certain of Nuvelo’s former and current officers and directors were named as defendants in a purported securities class action lawsuit filed in the U.S. District Court for the Southern District of New York. The suit alleged violations of the Securities Exchange Act of 1934 related to the clinical trial results of alfimeprase, which Nuvelo announced on December 11, 2006, and sought damages on behalf of purchasers of Nuvelo’s common stock during the period between January 5, 2006 and December 8,

2006. Specifically, the suit alleged that Nuvelo misled investors regarding the efficacy of alfimeprase and the drug’s likelihood of success. The plaintiff sought unspecified damages and injunctive relief. Three additional lawsuits were filed in the Southern District of New York on February 16, 2007, March 1, 2007 and March 6, 2007, respectively. On April 10, 2007, three separate motions to consolidate the cases, appoint lead plaintiff, and appoint lead plaintiff’s counsel were filed. On April 18, 2007, Nuvelo filed a motion to transfer the four cases to the Northern District of California. The Court granted Nuvelo’s motion to transfer the cases to the Northern District of California in July 2007. Plaintiffs have filed motions for consolidation, lead plaintiff and lead plaintiff’s counsel in the Northern District of California. Plaintiffs filed their consolidated complaint in the Northern District of California on November 9, 2007. Nuvelo filed a motion to dismiss plaintiffs consolidated complaint on December 21, 2007. Plaintiffs filed an opposition to Nuvelo’s motion to dismiss on February 4, 2008. On June 12, 2008, the Court held a hearing on the motion to dismiss.

On December 4, 2008, the Court issued an order dismissing plaintiff’s complaint, and granting leave to amend. On January 23, 2009, the plaintiffs filed an amended complaint, alleging similar claims. Based on the Court’s December 4, 2008 order, and plaintiff’s amended complaint, ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by its insurance providers. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the case is not finally dismissed, or if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

In addition, Variagenics, with which Nuvelo merged in 2003, has been named as a defendant in a securities class action lawsuit alleging the failure to disclose additional and excessive commissions purportedly solicited by and paid to underwriters who are also named defendants in the lawsuit. Plaintiffs in the suit allege that underwriters took these commissions and in exchange allocated shares of Variagenics’ stock to their preferred customers through alleged agreements with these preferred customers that tied the allocation of initial public offering shares to agreements by the customers to make additional aftermarket purchases at pre-determined prices. As a result of Nuvelo’s merger with Variagenics, ARCA is obligated to continue to defend against this litigation. ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will not be material to ARCA’s financial position or results of operations, and that any loss, settlement payment or attorneys’ fees accrued with respect to the suit will be paid by Nuvelo’s insurance provider. Because of a recent court ruling, the settlement class, as defined in the settlement papers, is no longer feasible. While a new complaint has not been filed against Nuvelo, there are several “focus” cases against other issuers in which new complaints have been filed. Defendant issuers in the “focus” cases filed motions to dismiss the new complaints. On March 26, 2008, the District Court issued an order granting in part and denying in part the “focus” issuers motions to dismiss. The “focus” issuers had been advised that plaintiffs intended to file new complaints against Nuvelo, but none have been filed yet. ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by Nuvelo’s insurance provider. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

If product liability lawsuits are successfully brought against ARCA, then ARCA will incur substantial liabilities and may be required to limit commercialization of Gencaro or other product candidates.

ARCA faces product liability exposure related to the testing of its product candidates in human clinical trials, and may face exposure to claims by an even greater number of persons once it begins marketing and distributing its products commercially. If ARCA cannot successfully defend itself against product liability claims, then it will incur substantial liabilities. Regardless of merit or eventual outcome, liability claims may result in:

•

decreased demand for its products and product candidates;

•

injury to its reputation;

•

withdrawal of clinical trial participants;

•

costs of related litigation;

•

substantial monetary awards to patients and others;

•

loss of revenues; and

•

the inability to commercialize its products and product candidates.

ARCA has obtained limited product liability insurance coverage. Such coverage, however, may not be adequate or may not continue to be available to ARCA in sufficient amounts or at an acceptable cost, or at all. ARCA may not be able to obtain commercially reasonable product liability insurance for any product approved for marketing.

Defending against claims relating to improper handling, storage or disposal of hazardous chemicals, radioactive or biological materials could be time consuming and expensive.

ARCA’s research and development of product candidates may involve the controlled use of hazardous materials, including chemicals, radioactive and biological materials. ARCA cannot eliminate the risk of accidental contamination or discharge and any resultant injury from the materials. Various laws and regulations govern the use, manufacture, storage, handling and disposal of hazardous materials. ARCA may be sued or be required to pay fines for any injury or contamination that results from its use or the use by third parties of these materials. Compliance with environmental laws and regulations may be expensive, and current or future environmental regulations may impair its research, development and production efforts.

The loss of any rights to market key products would significantly impair ARCA’s operating results.

ARCA has licensed from CPEC, who has licensed rights in Gencaro from BMS, the exclusive rights to Gencaro for all therapeutic and diagnostic uses in any country until the later of (i) 10 years from the first commercial sale of Gencaro in such country, or (ii) the termination of ARCA’s commercial exclusivity in such country. This license includes a sublicense to ARCA from BMS. ARCA is obligated to use commercially reasonable efforts to develop and commercialize Gencaro, including obtaining regulatory approvals. ARCA’s ability to develop and commercialize Gencaro is dependent on numerous factors, including some factors that are outside of its control. CPEC has the right to terminate ARCA’s license if ARCA materially breaches its obligations under the license agreement and fails to cure any such breach within the terms of the license.

If ARCA’s license agreement with CPEC is terminated for reasons related to non-payment of fees, or for any other breach, then ARCA would have no further rights to develop and commercialize Gencaro for any indication. The termination of this license, or of any other agreement which enables ARCA to market a key product or product candidate, could significantly and adversely affect ARCA’s business.

Third parties may own or control patents or patent applications that ARCA may be required to license to commercialize its product candidates or that could result in litigation that would be costly and time consuming.

ARCA’s ability to commercialize Gencaro and other product candidates depends upon its ability to develop, manufacture, market and sell these drugs without infringing the proprietary rights of third parties. A number of pharmaceutical and biotechnology companies, universities and research institutions have or may be granted patents that cover technologies similar to the technologies owned by or licensed to ARCA. ARCA may choose to seek, or be required to seek, licenses under third party patents, which would likely require the payment of license fees or royalties or both. ARCA may also be unaware of existing patents that may be infringed by Gencaro, the genetic testing ARCA intends to use in connection with Gencaro or its other product candidates. Because patent applications can take many years to issue, there may be other currently pending applications that may later result in issued patents that are infringed by Gencaro or ARCA’s other product candidates. Moreover, a license may not be available to ARCA on commercially reasonable terms, or at all.

There is a substantial amount of litigation involving patent and other intellectual property rights in the biotechnology and biopharmaceutical industries generally. If a third party claims that ARCA is infringing on its technology, then ARCA’s business and results of operations could be harmed by a number of factors, including:

•

infringement and other intellectual property claims, even if without merit, are expensive and time-consuming to litigate and can divert management’s attention from ARCA’s core business;

•

monetary damage awards for past infringement can be substantial;

•

a court may prohibit ARCA from selling or licensing product candidates unless the patent holder chooses to license the patent to ARCA; and

•

if a license is available from a patent holder, ARCA may have to pay substantial royalties.

ARCA may also be forced to bring an infringement action if it believes that a competitor is infringing its protected intellectual property. Any such litigation will be costly, time-consuming and divert management’s attention, and the outcome of any such litigation may not be favorable to ARCA.

ARCA’s intellectual property rights may not preclude competitors from developing competing products and ARCA’s business may suffer.

ARCA’s competitive success will depend, in part, on ARCA’s ability to obtain and maintain patent protection for its inventions, technologies and discoveries, including intellectual property that ARCA licenses. The patent positions of biotechnology companies involve complex legal and factual questions, and ARCA cannot be certain that ARCA’s patents and licenses will successfully preclude others from using ARCA’s technology. Although Gencaro has an established patent strategy, the timing of the grant of a patent cannot be predicted. Patent applications describing and seeking patent protection of methods, compositions or processes relating to proprietary inventions involving human therapeutics could require ARCA to generate data, which may involve substantial costs. In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued. Consequently, ARCA cannot be certain that any of its patent applications will result in the issuance of patents or, if any patents are issued, that they will provide significant market protection or will not be circumvented or challenged and found to be unenforceable or invalid. In some cases, patent applications in the U.S. and certain other jurisdictions are maintained in secrecy until patents issue, and since publication of discoveries in the scientific or patent literature often lags behind actual discoveries, ARCA cannot be certain of the priority of inventions covered by pending patent applications. Moreover, ARCA may have to participate in interference proceedings declared by the U.S. Patent and Trademark Office to determine priority of invention or in opposition proceedings in a foreign patent office, any of which could result in substantial cost to ARCA, even if the eventual outcome is favorable. There can be no assurance that a court of competent jurisdiction would hold any patents issued valid. An adverse outcome could subject ARCA to significant liabilities to third parties, require disputed rights to be licensed from third parties or require ARCA to cease using such technology. ARCA could also incur substantial costs in seeking to enforce its proprietary rights against infringement.

While the composition of matter patents on the compound have expired, ARCA holds the intellectual property arising from the discovery of the interaction of Gencaro with the polymorphisms of the ß ₁ and µ _2c receptors. ARCA has filed patent applications that claim the use of Gencaro with the diagnosis of a patient’s receptor genotype. ARCA’s NDA requested a label that will include a claim that efficacy varies based on receptor genotype and a recommendation in the prescribing information that prospective patients be tested for their receptor genotype. Under applicable law, a generic bucindolol label would likely be required to include this recommendation as it pertains directly to the safe or efficacious use of the drug. Such a label could be considered as inducing infringement, carrying the same liability as direct infringement. Even if the patents are granted, the approved label may not contain language covered by the patents, or ARCA may be unsuccessful in enforcing them.

ARCA may not be able to effectively protect its intellectual property rights in some foreign countries, as many countries do not offer the same level of legal protection for intellectual property as the U.S. Furthermore, the patent applications describing ARCA’s proprietary methods are filed only in the U.S.

ARCA requires its employees, consultants, business partners and members of its scientific advisory board to execute confidentiality agreements upon the commencement of employment, consulting or business relationships with ARCA. These agreements provide that all confidential information developed or made known during the course of the relationship with ARCA be kept confidential and not disclosed to third parties except in specific circumstances. In the case of employees, the agreements provide that all inventions resulting from work performed for ARCA, utilizing the property or relating to the business of ARCA and conceived or completed by the individual during employment shall be the exclusive property of ARCA to the extent permitted by applicable law.

Third parties may breach these and other agreements with ARCA regarding its intellectual property, and ARCA may not have adequate remedies for the breach. Third parties could also fail to take necessary steps to protect ARCA’s licensed intellectual property, which could seriously harm ARCA’s intellectual property position.

If ARCA is not able to protect its proprietary technology, trade secrets and know-how, then its competitors may develop competing products. Any issued patent may not be sufficient to prevent others from competing with ARCA. Further, ARCA has trade secrets relating to Gencaro, and such trade secrets may become known or independently discovered. ARCA’s issued patents and those that may issue in the future, or those licensed to ARCA, may be challenged, opposed, invalidated or circumvented, which could limit ARCA’s ability to stop competitors from marketing related products or the term of patent protection that ARCA may have for its product candidates. All of these factors may affect ARCA’s competitive position.

If the manufacture, use or sale of ARCA’s products infringe on the intellectual property rights of others, ARCA could face costly litigation, which could cause ARCA to pay substantial damages or licensing fees and limit its ability to sell some or all of its products.

Extensive litigation regarding patents and other intellectual property rights has been common in the biopharmaceutical industry. Litigation may be necessary to assert infringement claims, enforce patent rights, protect trade secrets or know-how and determine the enforceability, scope and validity of certain proprietary rights. The defense and prosecution of intellectual property lawsuits, U.S. Patent and Trademark Office interference proceedings, and related legal and administrative proceedings in the U.S. and internationally involve complex legal and factual questions. As a result, such proceedings are costly and time-consuming to pursue, and their outcome is uncertain.

Regardless of merit or outcome, ARCA’s involvement in any litigation, interference or other administrative proceedings could cause ARCA to incur substantial expense and could significantly divert the efforts of ARCA’s technical and management personnel. Any public announcements related to litigation or interference proceedings initiated or threatened against ARCA could cause ARCA’s stock price to decline. An adverse determination may subject ARCA to the loss of its proprietary position or to significant liabilities, or require ARCA to seek licenses that may include substantial cost and ongoing royalties. Licenses may not be available from third parties, or may not be obtainable on satisfactory terms. An adverse determination or a failure to obtain necessary licenses may restrict or prevent ARCA from manufacturing and selling its products, if any. These outcomes could materially harm ARCA’s business, financial condition and results of operations.

Item 1B.

Unresolved Staff Comments

Not applicable.

Item 2.

Properties

The Company’s headquarters facility consists of approximately 15,000 square feet of newly constructed office space in Broomfield, Colorado, which is leased until June 2013. It also leases approximately 1,500 square feet of laboratory facilities located in Aurora, Colorado.

In January 2005, the Company entered into a seven-year facility lease agreement for 61,826 square feet of industrial space in San Carlos, California. A subtenant leases approximately 6,754 square feet of this space, and the Company currently plans to sublet additional portions of this facility.

The Company also leases approximately 139,000 square feet of space in Sunnyvale, California, which it has leased to a subtenant through May 31, 2011.

The Company believes that these facilities are adequate to meet its current needs.

Item 3.

Legal Proceedings

On February 9, 2007, Nuvelo and certain of Nuvelo’s former and current officers and directors were named as defendants in a purported securities class action lawsuit filed in the United States District Court for the Southern District of New York. The suit alleges violations of the Securities Exchange Act of 1934 related to the clinical trial results of alfimeprase, which Nuvelo announced on December 11, 2006, and seeks damages on behalf of purchasers of Nuvelo’s common stock during the period between January 5, 2006 and December 8, 2006. Specifically, the suit alleges that Nuvelo misled investors regarding the efficacy of alfimeprase and the drug’s likelihood of success. The plaintiff seeks unspecified damages and injunctive relief. Three additional lawsuits were filed in the Southern District of New York on February 16, 2007, March 1, 2007 and March 6, 2007, respectively. On April 10, 2007, three separate motions to consolidate the cases, appoint lead plaintiff, and appoint lead plaintiff’s counsel were filed. On April 18, 2007, Nuvelo filed a motion to transfer the four cases to the Northern District of California. The Court granted Nuvelo’s motion to transfer the cases to the Northern District of California in July 2007. Plaintiffs have filed motions for consolidation, lead plaintiff and lead plaintiff’s counsel in the Northern District of California. Plaintiffs filed their consolidated complaint in the Northern District of California on November 9, 2007. Nuvelo filed a motion to dismiss plaintiffs consolidated complaint on December 21, 2007. Plaintiffs filed an opposition to Nuvelo’s motion to dismiss on February 4, 2008. On June 12, 2008, the Court held a hearing on the motion to dismiss.

On December 4, 2008, the Court issued an order dismissing plaintiff’s complaint, and granting leave to amend. On January 23, 2009, plaintiffs filed an amended complaint, alleging similar claims. Based on the Court’s December 4, 2008 order, and plaintiff’s amended complaint, ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by its insurance providers. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the case is not finally dismissed, or if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

on Form S-1 filed with the SEC in July 2000 and the prospectus, a part of the registration statement, materially false and misleading. Plaintiffs seek unspecified damages. On or about April 19, 2002, an amended complaint was filed which makes essentially the same allegations. On or about July 15, 2002, Variagenics and the individuals filed a motion to dismiss. The Company is involved in this litigation as a result of Nuvelo’s merger with Variagenics in January 2003. On July 16, 2003, Nuvelo’s board of directors approved a settlement proposal initiated by the plaintiffs. However, because of a recent court ruling, the settlement class, as defined in the settlement papers, is no longer feasible. While a new complaint has not been filed against Nuvelo, there are several “focus” cases against other issuers in which new complaints have been filed. Defendant issuers in the “focus” cases filed motions to dismiss the new complaints. On March 26, 2008, the District Court issued an order granting in part and denying in part the “focus” issuers motions to dismiss. The “focus” issuers had been advised that plaintiffs intended to file new complaints against Nuvelo, but none have been filed yet. ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by Nuvelo’s insurance provider. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

Item 4.

Submission of Matters to a Vote of Security Holders

A special meeting of the stockholders of Nuvelo was held on Wednesday, January 7, 2009 to consider matters related to the then still-proposed merger contemplated by the Merger Agreement. At the special meeting, the following proposals were approved by Nuvelo’s stockholders:

To approve the issuance of shares of Nuvelo’s common stock pursuant to the Merger Agreement; and

To adjourn the special meeting to solicit additional proxies in favor of a proposal to amend Nuvelo’s amended and restated certificate of incorporation to effect a reverse stock split of the issued and outstanding shares of Nuvelo’s common stock.

The following is a tabulation of the votes cast with respect to these proposals:


	Votes
Proposal	For	Against	Abstain
1	26,184,584	3,495,798	179,936
2	25,401,442	4,118,506	340,370

At the special meeting, notice of the time and date of the adjourned meeting, 9:00 a.m. Pacific time on January 23, 2009, was provided and the special meeting was adjourned. On January 23, 2009, at the adjourned meeting, Nuvelo’s stockholders approved the proposal to amend Nuvelo’s amended and restated certificate of incorporation to effect a reverse stock split of the issued and outstanding shares of Nuvelo’s common stock. The following is a tabulation of the votes cast with respect to this proposal:


Votes
For	Against	Abstain
27,518,491	4,391,237	212,480

PART II

Item 5.

Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Nuvelo’s common stock began trading on the Nasdaq Global Market on August 8, 1997 as Hyseq, Inc. (HYSQ) and has traded under the symbol “NUVO” from January 31, 2003 to January 27, 2009 (except for the period between June 19, 2003 and March 19, 2004, where we temporarily traded under the symbol “NUVOD”). After the close of market on January 27, 2009, Nuvelo completed a 20-to-1 reverse stock split of its common stock and changed its name to ARCA biopharma, Inc. On January 28, 2009, ARCA’s common stock began trading on the Nasdaq Global Market on a post-reverse-split basis under the new symbol “ABIO.” Unless otherwise indicated, all per share amounts, except for the par value per share, in this Form 10-K have been adjusted retroactively to reflect the reverse stock split.

The following table sets forth, for the periods indicated, the high and low sales prices for Nuvelo’s common stock, as reported by the Nasdaq Global Market under these symbols and as adjusted for the reverse stock split:


	High		Low
Year ended December 31, 2007
First quarter	$	82.40	$	60.80
Second quarter		132.60		51.00
Third quarter		60.60		30.40
Fourth quarter		54.00		25.20

Year ended December 31, 2008
First quarter	$	37.60	$	11.00
Second quarter		19.40		11.00
Third quarter		15.00		6.80
Fourth quarter		9.40		4.21

Stockholders

As of March 17, 2009, ARCA had approximately 177 stockholders of record of its common stock, and the last sale price reported on the Nasdaq Global Market for Nuvelo’s common stock was $4.00 per share.

Dividend Policy

The holders of ARCA’s common stock are entitled to dividends in such amounts and at such times, if any, as may be declared by ARCA’s Board of Directors out of legally available funds. Nuvelo has not paid any dividends on its common stock, and ARCA does not anticipate paying any cash dividends on its common stock in the foreseeable future.

Securities Authorized for Issuance Under Equity Compensation Plans

Information relating to Nuvelo’s equity compensation plans as of December 31, 2008, under which Nuvelo’s equity securities were authorized for issuance, is included in Item 12 of Part III of this Annual Report.

Unregistered Sales of Equity Securities and Use of Proceeds

None.

Issuer Purchases of Equity Securities

None.

Item 6.

Selected Financial Data

Not applicable.

Item 7.

Management’s Discussion and Analysis of Financial Condition and Results of Operations

We have included or incorporated by reference into this Management’s Discussion and Analysis of Financial Condition and Results of Operations and elsewhere in this Annual Report on Form 10-K, and from time to time our management may make, statements that constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Forward-looking statements may be identified by words including “anticipate,” “plan,” “believe,” “intend,” “estimate,” “expect,” “should,” “may,” “potential” and similar expressions. Such statements are based on our management’s current expectations and involve risks and uncertainties. Our actual results and performance could differ materially from those projected in the forward-looking statements as a result of many factors discussed in this Annual Report, including those set forth in this Item 7 as well as under “Item 1. Business” and “Item 1A. Risk Factors.” We do not intend to update any of the forward-looking statements after the date of this Annual Report to conform these statements to actual results unless required by law.

Merger of ARCA and Nuvelo

On January 27, 2009, ARCA, which then was named Nuvelo, Inc., or Nuvelo, completed the merger contemplated by that Agreement and Plan of Merger and Reorganization, dated September 24, 2008, as amended October 28, 2008, by and among Nuvelo, Dawn Acquisition Sub, Inc., a wholly-owned subsidiary of Nuvelo, or Merger Sub, and ARCA biopharma, Inc., or ARCA, a privately held developmental-stage biopharmaceutical company based in Broomfield, Colorado, which merger agreement, as amended, is referred to herein as the Merger Agreement.

In accordance with the Merger Agreement, immediately prior to the consummation of the merger, Nuvelo effected a reverse stock split of its common stock. Pursuant to this reverse stock split, each 20 shares of Nuvelo’s common stock that were issued and outstanding immediately prior to the merger were converted into one share of Nuvelo’s common stock. In addition, pursuant to the Merger Agreement, Merger Sub merged with and into ARCA, with ARCA continuing after the merger as the surviving corporation and a wholly-owned subsidiary of Nuvelo. Immediately following the merger, Nuvelo changed its name to ARCA biopharma, Inc.

Unless otherwise indicated, all references herein to “ARCA” refer to ARCA both before and after the completion of the merger, and all references to “Nuvelo” refer to Nuvelo prior to the completion of the merger and the name change. The financial information included in this Management’s Discussion and Analysis of Financial Condition and Results of Operations is that of Nuvelo, not that of ARCA.

Under the terms of the Merger Agreement, holders of ARCA capital stock prior to the merger were entitled to receive shares of post-merger ARCA common stock, such that Nuvelo stockholders were expected to own approximately 33% of the common stock of the combined company immediately after the merger and ARCA stockholders, together with holders of ARCA options and warrants, were expected to own or had the right to acquire approximately 67% of the common stock of the combined company immediately after the merger, after giving effect to the issuance of shares pursuant to outstanding options and warrants primarily on the treasury stock method. The merger is intended to qualify for federal income tax purposes as a tax-free reorganization under the provisions of Section 368(a) of the U.S. Internal Revenue Code of 1986, as amended.

The merger will be treated by ARCA as a reverse merger and accounted for as a business combination using the purchase method of accounting in accordance with Statement of Financial Accounting Standards No. 141 (Revised 2007), “ Business Combinations ” (SFAS 141R). For accounting purposes, ARCA is considered to have acquired Nuvelo in the merger, as the stockholders of ARCA prior to the merger now have a controlling interest

in the combined company and ARCA’s management is the management of the combined company. As a result, the results of operations and financial position of Nuvelo as reported herein are not indicative of the future results of operations and financial position of the combined company

In connection with the merger, approximately 26 of Nuvelo’s employees were terminated in January 2009, and a substantial majority of the remaining Nuvelo employees are retained for a transition period of up to 12 weeks. Total termination benefits related to employees terminated in January 2009 and those on a transition plan were estimated to be $5.0 million.

Overview

ARCA biopharma, Inc., or ARCA, is a biopharmaceutical company developing genetically-targeted therapies for heart failure and other cardiovascular diseases. ARCA’s lead product candidate is Gencaro (bucindolol hydrochloride), a twice-a-day oral formulation that has been developed for the treatment of chronic heart failure. ARCA believes it has identified common genetic variations that help predict patient response to Gencaro. The FDA accepted ARCA’s NDA for Gencaro in September 2008. ARCA believes that Gencaro, if approved, will be the first genetically-targeted cardiovascular drug.

ARCA holds worldwide rights to Gencaro and, if it is approved, currently plans to commercialize the drug in the U.S., through its own specialized sales force. ARCA intends to seek commercial partners outside the United States. ARCA has collaborated with Laboratory Corporation of America, or LabCorp, to develop and launch a companion genetic test for Gencaro, in conjunction with any commercialization of Gencaro.

ARCA is in the development stage and, since inception, ARCA’s activities have been focused primarily on conducting research and development, hiring personnel and raising capital to support these activities. ARCA has incurred net losses since inception and expects to incur net losses in the future as research and development activities continue and it prepares to commercialize Gencaro.

ARCA’s costs associated with Gencaro have represented substantially all of ARCA’s research and development expenses to date. ARCA expects significant costs for the foreseeable future while it awaits the FDA’s decision on the NDA for Gencaro and builds its sales and marketing organization in anticipation of the potential commercial launch of Gencaro. ARCA has not generated any revenues from sales of commercial products since inception and does not expect to generate any revenues unless and until the NDA for Gencaro is approved. During 2009, ARCA expects to focus its research and development efforts on obtaining Gencaro approval, investigating potential new indications, developing an international regulatory strategy and furthering its cardiovascular pipeline development. Due to the significant reduction in the scope of Nuvelo’s research and development efforts, ARCA anticipates a significant reduction in combined spending in 2009 as compared with 2008.

NU172

NU172 is a novel, short-acting anticoagulant that ARCA plans to develop as a potential new therapy in indications where heparin paired with its antidote, protamine, are the current standard of care, such as coronary artery bypass graft (CABG) surgery, kidney dialysis and a variety of vascular surgical and coronary interventions.

ARCA is developing NU172 through a collaboration with Archemix Corporation, under which ARCA is responsible for development and worldwide commercialization of NU172 and other potential product candidates that may be developed under this collaboration. In February 2008, Nuvelo paid Archemix a $1.0 million milestone fee in connection with the dosing of the first patient in the Phase I trial for NU172. If ARCA enrolls the first patient in a Phase II trial of NU172, ARCA will be obligated to pay Archemix a $3.0 million milestone fee. ARCA is currently conducting preclinical studies and evaluating a potential Phase II study in CABG patients in 2009.

Unless otherwise indicated, the following discussions of historical results of operations, cash flows information, and sources and uses of capital are that of Nuvelo prior to the merger with ARCA.

Results of Operations

Contract Revenues

Contract revenues were $15.3 million in 2008, as compared with $46.9 million in 2007.

In 2008, Nuvelo recorded as revenue $15.0 million that was received from Bayer HealthCare AG, or Bayer, in connection with the termination of its collaboration agreement in June 2007. Following Nuvelo’s decision to discontinue further clinical development of alfimeprase that was announced in March 2008, the $15.0 million, which had been recorded as deferred revenue, was recognized as revenue in May 2008 upon the expiration of the notice period, as defined in the termination agreement with Bayer.

In 2007, Nuvelo recorded as revenue $44.9 million of the $50.0 million up-front license fee received from Bayer in January 2006 as a result of the termination of its collaboration agreement in June 2007. The up-front license fee had been recorded as deferred revenue upon receipt and was being recognized on a straight-line basis over the performance period under the agreement, originally estimated to be through September 2020.

Research and Development Expenses


	Years Ended December 31,				% Change
	2008		2007		% Change
	(In thousands)
Research and development	$	27,764	$	42,654	(35	%)

Research and development, or R&D, expenses primarily consist of clinical trial and drug manufacturing costs, personnel costs, including related stock-based compensation expense, license, collaboration and allocated facilities expenses.

R&D expenses for Nuvelo’s significant programs were as follows for the periods indicated (including upfront fees and collaboration cost-sharing credits, and excluding occupancy costs and stock-based compensation expense):


	Since Inception		Years Ended December 31,
Program	Since Inception		2008		2007
			(In millions)
Alfimeprase	$	124.2	$	4.8	$	8.3
NU172	$	18.4	$	5.3	$	8.0
NU206	$	14.1	$	4.5	$	3.6

The decrease in R&D expenses of $14.9 million in 2008, as compared with 2007, was primarily attributable to the following: a $4.1 million decrease in rNAPc2-related expenses due to Nuvelo’s suspension of development of rNAPc2 in 2007, a $3.5 million decrease in alfimeprase-related expenses due to the discontinuance of development of alfimeprase announced in March 2008, a $2.7 million decrease in NU172-related expenses, and a $3.4 million decrease in employees’ stock-based compensation expense as a result of a reduction in headcount. The decrease in NU172-related expenses in 2008 was primarily due to a decrease in manufacturing costs, partially offset by increases in clinical trial and collaboration expenses as a result of the initiation of the Phase I trials in 2008.

The timing, cost of completing the clinical development of any product candidate, and any potential future product revenues will depend on a number of factors, including the maintenance of existing collaboration agreements with cost-sharing arrangements, disease or medical condition to be treated, clinical trial design and endpoints, availability of patients to participate in trials and the relative efficacy of the product versus treatments already approved.

General and Administrative Expenses


	Years Ended December 31,				% Change
	2008		2007		% Change
	(In thousands)
General and administrative	$	14,939	$	20,762	(28	%)

General and administrative, or G&A, expenses primarily consist of personnel costs, including related stock-based compensation expense, consulting and professional fees, insurance, facilities and depreciation expenses, and various other administrative costs.

The decrease in G&A expenses of $5.8 million in 2008, as compared with 2007, was primarily due to a $4.6 million decrease in personnel related costs, of which $2.0 million was related to employee stock-based compensation expense, as a result of a reduction in headcount and a $1.1 million charge related to the impairment of software implementation costs in 2007. In connection with the recently completed merger, Nuvelo incurred $1.8 million of expenses in 2008, which were primarily related to financial advisory, accounting and legal fees, as well as costs of preparing, printing and distributing the proxy statement for the special meeting of Nuvelo’s stockholders. These merger-related expenses were largely offset by reductions in temporary services, consulting and other professional fees in 2008 as compared with 2007.

Restructuring Expense

On March 17, 2008, Nuvelo announced its decision to discontinue alfimeprase clinical development and restructure to make additional resources available for its other research and development programs. In connection with the restructuring, Nuvelo reduced its workforce by approximately 19% and recorded a restructuring expense of $2.5 million, including $1.3 million of termination benefits and $1.2 million of non-cash stock-based compensation expense.

On August 1, 2007, Nuvelo announced a reduction in its workforce by approximately 30% to realign its organization to focus on core development programs that it believed would produce nearest-term proof-of-concept data. In addition, Nuvelo announced the decision to suspend development of rNAPc2 in all indications including cancer and acute coronary syndromes. As a result, Nuvelo recorded a restructuring expense of $2.3 million, including $1.4 million of termination benefits and $0.9 million of non-cash stock-based compensation expense.

Facility Exit Costs

In December 2006, Nuvelo ceased use of its facility in Sunnyvale, California, referred to herein as the Sunnyvale facility, as it was no longer required for its business, and recorded a liability to reflect the estimated fair value of future lease-related payments for the remainder of the lease term, less estimated sublease income. In March 2008, Nuvelo determined that the likelihood of subleasing the Sunnyvale facility during the remainder of the lease term had become remote and, therefore, recorded a $1.5 million charge to reflect such change in the sublease assumption. Nuvelo continued to actively market the facility for sublease. In December 2008, Nuvelo entered into a sublease agreement and recorded a $2.1 million credit, to reflect the change in estimated fair value of the remaining lease obligations after taking into consideration of future cash flows from the sublease. For the year ended December 31, 2008, Nuvelo recorded a net $0.6 million credit as a result of the changes in the sublease assumption. Additionally, in connection with the execution of the sublease agreement, the landlord of the Sunnyvale facility agreed to release Nuvelo from the facility restoration obligation. As a result, Nuvelo reversed this accrual and recorded a $0.8 million credit in December 2008.

Impairment of Goodwill

In 2008, Nuvelo performed a goodwill impairment test due to the significant decline of its stock price subsequent to the announcement of the discontinuation of alfimeprase discussed above. As a result of the impairment test, Nuvelo determined that goodwill was impaired. Accordingly, Nuvelo recorded an impairment charge of the full balance of goodwill totaling $4.7 million in 2008.

Interest Income, Net

Net interest income was $2.4 million in 2008, as compared with $6.6 million in 2007. The decrease in net interest income in 2008 was primarily due to declining balances in cash equivalents and marketable securities and a substantial reduction in the yield on cash equivalents and marketable securities.

Other Income

In connection with the sale of Nuvelo’s subsidiary in December 2004, Nuvelo received a convertible promissory note with a principal amount of $0.9 million, for which Nuvelo had initially assessed the value to be zero due to its assessment of the probability of collection. In December 2008, Nuvelo received a full payment of the promissory note. As a result, Nuvelo recorded the $0.9 million as other income in its statement of operations.

Net Loss

Since Nuvelo’s inception, Nuvelo has incurred significant net losses, and as of December 31, 2008, its accumulated deficit was $500.4 million. Nuvelo incurred a net loss of $29.9 million in 2008, as compared with a net loss of $12.3 million in 2007. The increase in net loss was primarily due to a decrease in contract revenues and an impairment of goodwill, partially offset by an overall reduction in R&D and G&A expenses, as noted above.

Liquidity and Capital Resources

Cash and Cash Equivalents, Marketable Securities and Restricted Cash


	December 31, 2008		December 31, 2007
	(In thousands)
Cash and cash equivalents	$	35,891	$	32,061
Marketable securities		15,081		65,506
Restricted cash(1)		6,000		6,000

	$	56,972	$	103,567

(1)	ARCA has a $6.0 million letter of credit issued to the landlord of its Sunnyvale facility as required by the lease agreement of this facility, and the letter of credit is being collateralized by a certificate of deposit of the same amount, which is recorded as restricted cash.

As of December 31, 2008, Nuvelo had total cash and cash equivalents, marketable securities and restricted cash of $57.0 million, as compared to $103.6 million as of December 31, 2007. The decrease of $46.6 million resulted primarily from operating expenditures during the period.

As of December 31, 2008, all of Nuvelo’s investments in marketable securities were classified as available-for-sale securities, as defined by Statement of Financial Accounting Standards No. 115, “Accounting for Certain Investments in Debt and Equity Securities.” They were recorded at their fair value and primarily consisted of corporate debt securities. Nuvelo has made its investments in accordance with its investment policy. The primary objectives of Nuvelo’s investment policy are liquidity and safety of principal.

Cash Flows from Operating, Investing and Financing Activities


	Years Ended December 31,
	2008			2007
	(In thousands)
Net cash provided by (used in):
Operating activities	$	(46,508	)	$	(45,958	)
Investing activities		50,183			21,085
Financing activities		155			(3,401	)

Net increase (decrease) in cash and cash equivalents	$	3,830		$	(28,274	)

The net cash used in operating activities in 2008 was comparable with 2007. Reductions in R&D and G&A expenses in 2008 were largely offset by the receipt of $15.0 million from Bayer related to the termination of the collaboration agreement in 2007.

The increase in net cash provided by investing activities in 2008 as compared with 2007 was primarily due to an increase in maturities, net of purchases, of marketable securities.

The change in net cash provided by or used in financing between 2008 and 2007 was primarily because Nuvelo paid in full in 2007 the remaining principal balances related to its related party line of credit and the loans from Silicon Valley Bank totaling $3.8 million.

Sources and Uses of Capital

Nuvelo’s primary sources of liquidity to date have been financing activities and collaboration receipts. Nuvelo’s primary uses of capital resources to date have been to fund operating activities, including research, clinical development and drug manufacturing expenses, license payments, and spending on capital items.

Under the collaboration agreement with Archemix, Archemix is responsible for the discovery of short-acting aptamers targeting the coagulation cascade for use in acute cardiovascular procedures, and ARCA is responsible for development and worldwide commercialization of these product candidates. If the first patient is enrolled in a Phase II trial of NU172, which may occur in 2009, a $3.0 million milestone fee is payable to Archemix. In addition, ARCA is obligated to purchase Archemix common stock having a value equal to the lesser of $10.0 million or 15% of the total gross proceeds raised by Archemix in a qualified public offering of Archemix stock occurring within five years of the effective date of the collaboration agreement.

ARCA believes that its current cash, cash equivalents and marketable securities balances are sufficient to fund operations through at least December 31, 2009. However, because of ARCA’s substantial capital requirements necessary to fund commercialization of Gencaro, if approved, ARCA will seek to access public or private debt or equity markets. ARCA’s future capital requirements depend on a number of factors, including, but not limited to, the following:

•

timing and outcomes of regulatory approvals, in particular the approval of ARCA’s NDA for Gencaro by the FDA;

•

the extent to which ARCA is able to acquire or in-license new products, technologies or businesses;

•

the costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; and

•

the terms and timing of any additional collaborative, strategic partnership or licensing agreements that ARCA may establish.

If ARCA’s available cash and cash equivalents and funding received or made available are insufficient to satisfy its liquidity requirements, or if ARCA develops additional products or pursues additional applications for its products or conducts additional clinical trials beyond those currently contemplated, ARCA may seek to sell additional equity or incur additional indebtedness. The sale of additional equity or convertible debt securities may result in additional dilution to ARCA’s stockholders. If ARCA raises additional funds through the incurrence of additional indebtedness, the obligations related to such indebtedness would be senior to rights of holders of ARCA capital stock and could contain covenants that would restrict ARCA’s operations. Should additional capital not be available to ARCA in the near term, ARCA may be required to delay or suspend research, development and/or commercialization activities to conserve its cash resources. Should ARCA be unable to raise additional capital or if the terms of available capital are not acceptable to ARCA, ARCA’s management believes that the level of activities and expenditures can be adjusted, if necessary, such that current funds available to ARCA would allow ARCA to continue operations through at least December 31, 2009.

Critical Accounting Policies and Estimates

Nuvelo’s discussion and analysis of its operating results and financial condition is based upon Nuvelo’s consolidated financial statements, which were prepared in accordance with accounting principles generally accepted in the United States of America. The preparation of the financial statements required Nuvelo to make estimates, judgments, and assumptions that affected the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent amounts. While Nuvelo believed its estimates, judgments and assumptions were reasonable, the inherent nature of estimates is that actual results will likely differ from the estimates made. Nuvelo’s significant accounting policies are described in Note 1 to the Consolidated Financial Statements included in this Report. Nuvelo believed the following critical accounting policies affected its most significant judgments, assumptions, and estimates used in the preparation of its consolidated financial statements and, therefore, are important in understanding its financial condition and results of operations.

Clinical Trial and Drug Manufacturing Expenses

Costs related to clinical trial and drug manufacturing activities were based upon estimates of the services received and related expenses incurred by the contract research organizations, or CROs, clinical study sites, drug manufacturers, collaboration partners, laboratories, consultants, or otherwise. Related contracts varied significantly in length, and could be for a fixed amount, a variable amount based on actual costs incurred, capped at a certain limit, or for a combination of these elements. Nuvelo monitored the activity levels through close communication with the CROs and other vendors, including detailed invoice and task completion review, analysis of expenses against budgeted amounts, and pre-approval of any changes in scope of the services to be performed. Nuvelo also requested certain significant vendors to provide an estimate of costs incurred but not invoiced on a periodic basis. For accrual of expenses related to CROs and clinical study sites, Nuvelo’s estimate was primarily based on patient enrollment or progress made against specified milestones or targets in each period, which was reported by the CROs or other third parties. All estimates may differ from the actual amounts subsequently invoiced. No adjustments for material changes in estimates were recognized in any period presented.

In accordance with Statement of Financial Accounting Standards No. 2, “Accounting for Research and Development Costs,” Nuvelo capitalized clinical trial drug manufacturing costs as “clinical trial supplies,” a current asset on Nuvelo’s balance sheet, as long as there were alternative future uses for the related clinical trial drug material in other indications not currently being studied. During 2007 and 2008, Nuvelo determined that there were no alternative future uses of clinical trial supplies for all current drug programs and that all expenditures related to clinical trial supplies were charged to expense as incurred.

development activities until the related goods are delivered or the related services are performed. The adoption of EITF 07-3 did not have a material effect on Nuvelo’s consolidated financial position and results of operations.

Revenue Recognition

Nuvelo recognized revenue in accordance with Staff Accounting Bulletin No. 104, “Revenue Recognition” (SAB 104), when (i) persuasive evidence of an arrangement existed, (ii) delivery has occurred or services have been rendered, (iii) the price was fixed and determinable, and (iv) collectibility was reasonably assured. In situations where there were no continuing performance obligations, or continuing obligations were perfunctory or inconsequential, Nuvelo recognized up-front non-refundable fees as revenues on the effective date of the related agreement. Up-front non-refundable licensing fees that required continuing involvement in the form of development, manufacturing or other commercialization efforts by Nuvelo were recognized as revenue ratably over the performance period. Judgment was required in determining this performance period, and the effects of any changes to the estimated period are recognized prospectively.

Nuvelo evaluated revenue from agreements that had multiple elements to determine whether the components of the arrangement represented separate units of accounting as defined in EITF Issue No. 00- 21, “ Revenue Arrangements with Multiple Deliverables” (EITF 00-21). To recognize revenue for a delivered item in a multiple element arrangement, EITF 00-21 requires that the delivered items have value to the customer on a stand-alone basis, there is objective and reliable evidence of fair value of the undelivered items, and delivery of any undelivered items is probable and within Nuvelo’s control if delivered items have a general right of return. The determination that multiple elements in an arrangement met the criteria for separate units of accounting required Nuvelo to exercise its judgment.

Stock-based Compensation

Nuvelo accounted for stock-based compensation expense in accordance with the provisions of Statement of Financial Accounting Standards No. 123 (revised 2004), “Share-Based Payment” (SFAS 123R). Under SFAS 123R, employee stock-based compensation cost is generally measured at the grant date, based on the fair value of the award, and is recognized as an expense over the employee’s requisite service period, net of estimated forfeitures.

Nuvelo used the Black-Scholes option–pricing model as management believed that it was the most appropriate fair-value method for Nuvelo’s stock-based awards. The Black-Scholes option–pricing model requires assumptions to be made for the expected term of the awards, expected volatility of Nuvelo’s stock price, risk-free interest rates and expected dividend yields. These assumptions were highly subjective and involve inherent uncertainties and were based on management’s best estimates and judgment. If alternative assumptions were used instead of those presented in the notes to the financial statements, stock-based compensation expense could be materially different from amounts recorded in the financial statements under SFAS 123R. In addition, under SFAS 123R Nuvelo was required to estimate the expected forfeiture rate of awards and only recognized expense for those awards expected to vest. If the actual forfeiture rate was materially different from the estimate, the stock-based compensation expense could be materially different from amounts recorded in the financial statements. For options granted prior to January 1, 2006, Nuvelo continued to use the graded-vested (multiple-option) method for expense attribution. For options granted since January 1, 2006, Nuvelo used the straight-line (single-option) method for expense attribution, estimates forfeitures based on historical data and only recognized expense for those shares expected to vest. Adjustments to the forfeiture rate were made if actual forfeitures differed from previous estimates.

To determine the expected term of the options granted, Nuvelo used historical data, including post-vesting termination behavior and the contractual term to estimate future exercises and cancellations. The expected volatility was based on a combination of historic and implied volatility of Nuvelo’s common stock. The risk-free

interest rate assumptions were based on the yield of U.S. Treasury instruments with similar durations as the expected term of the related awards. The expected dividend yield assumption was based on Nuvelo’s historic and expected dividend payouts.

Nuvelo accounted for stock-based compensation expense for non-employee awards based on the fair values estimated using the Black-Scholes model on the date of grant and re-measured at each reporting date until vested, in compliance with Emerging Issues Task Force No. 96-18, “ Accounting for Equity Instruments That Are Issued to Other Than Employees for Acquiring, or in Conjunction with Selling, Goods or Services . ” Nuvelo used the straight-line method to expense the value associated with non-employee awards.

Goodwill and Other Long-Lived Assets—Impairment Assessments

Nuvelo tested goodwill for impairment using a fair value approach at the reporting unit level on an annual basis or when events indicated that the carrying value of the asset might be impaired in accordance with Statement of Financial Accounting Standards No. 142, “ Goodwill and other Intangible Assets , ” (SFAS 142). Consistent with the determination that Nuvelo had only one reporting segment, it had determined that there was only one reporting unit and, therefore, goodwill was tested at the entity level. Nuvelo elected October 31 ^st as its measurement date. Nuvelo completed its last annual goodwill test as of October 31, 2007, and no impairments were recognized.

SFAS 142 requires a two-step test for goodwill impairment. In the first step, Nuvelo compared the fair value of Nuvelo to its carrying value. Nuvelo generally based its fair value on its market capitalization, which was based on quoted market prices of its common stock, taking into account other factors that might affect the fair value of Nuvelo as a whole. Significant judgment is required to evaluate the fair value of a company, as quoted market prices of a company’s common stock and consequently market capitalization may experience significant fluctuations in reaction to disclosures of new information about the company. If the fair value of Nuvelo exceeded the carrying value of its net assets, goodwill was not impaired and Nuvelo was not required to proceed to the second step of the impairment test.

After Nuvelo announced its decision to discontinue alfimeprase clinical development in 2008, it experienced a significant decline of its stock price. Nuvelo management determined that Nuvelo’s fair value was lower than the carrying value of its net assets and that its goodwill was impaired. As a result, Nuvelo proceeded to perform the second step of the goodwill impairment test in order to determine the implied fair value of the goodwill and compare it to the carrying value of goodwill. The activities in the second step included valuing the tangible and intangible assets and liabilities of Nuvelo based on their fair value and determining the implied goodwill based upon the difference between the fair value of the reporting unit and the net fair values of identified tangible and intangible assets and liabilities. Based on the results of the second step of calculating the implied goodwill, Nuvelo recorded an impairment charge of the full balance of goodwill totaling $4.7 million.

In accordance with Statement of Financial Accounting Standards No. 144, “ Accounting for Impairment or Disposal of Long-Lived Assets ” (SFAS 144), Nuvelo evaluated long-lived assets, other than goodwill, for impairment whenever events or changes in circumstances indicated that the carrying value of an asset might not be recoverable based on expected undiscounted cash flows attributable to that asset. The amount of any impairment was measured as the difference between the carrying value and the fair value of the impaired asset.

Assumptions and estimates about future values and remaining useful lives are complex and often subjective. They can be affected by a variety of factors, including external factors such as industry and economic trends, competition to Nuvelo’s products and internal factors such as changes in Nuvelo’s business strategy and Nuvelo’s internal forecasts. Although Nuvelo believed the assumptions and estimates Nuvelo made in the past were reasonable and appropriate, different assumptions and estimates and certain events could materially impact Nuvelo’s reported financial results.

Exit and Disposal Activities

Nuvelo recorded costs and liabilities associated with exit and disposal activities, as defined in SFAS 146, at fair value in the period the liability was incurred. SFAS 146 requires that the estimated future cash flows to be used in the fair value calculation be discounted using a credit-adjusted risk-free interest rate and that such interest rate shall have a maturity date that approximates the expected timing of future cash flows. Future cash flows related to lease obligations shall include the effect of sublease rental income and other lease operating expenses. Nuvelo re-evaluated its sublease assumptions on a quarterly basis considering current market data, including vacancy rates and lease activities for similar facilities within the area. In periods subsequent to initial measurement, changes to the liability resulting from changes in sublease assumptions were measured using the same credit-adjusted risk-free rate that was applied in the initial period. In addition, accretion of the liability due to the passage of time was recorded as an expense.

In December 2006, Nuvelo exited the facility located in Sunnyvale, California, and recorded a liability of $26.6 million related to the remaining lease obligations, less estimated sublease income, for the remainder of the lease term. As of March 31, 2008, Nuvelo determined that the likelihood of subleasing this facility during the remainder of the lease term had become remote and, therefore, recorded an additional $1.5 million charge to reflect such change in the sublease assumption. Nuvelo continued to actively market the facility for sublease. In December 2008, Nuvelo entered into a sublease agreement and recorded a credit of $2.1 million in its statement of operations, to reflect the change in estimated fair value of the remaining lease obligations after taking into consideration future cash flows from the sublease. For the year ended December 31, 2008, Nuvelo recorded a net credit of $0.6 million due to the above changes in sublease assumption.

Income Taxes

Income taxes were accounted for under the liability method pursuant to Statement of Financial Accounting Standards No. 109, “Accounting for Income Taxes” (SFAS 109). Under SFAS 109, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

Nuvelo recorded a valuation allowance to reduce deferred tax assets to an amount that was more likely than not to be realized. Assessment of the realization of deferred income tax assets requires that estimates and assumptions be made as to the taxable income of future periods. Nuvelo’s deferred tax assets had been reduced to zero, as Nuvelo’s management believed that it was more likely than not that the deferred tax assets would not be realized. Projection of future period earnings was inherently difficult as it involved consideration of numerous factors such as Nuvelo’s overall strategies and estimates of new product development and acceptance, product lifecycles, selling prices and volumes, responses by competitors, manufacturing costs and assumptions as to operating expenses and other industry specific and macro and micro economic factors. In addition, consideration was also given to ongoing and constantly evolving global tax laws and Nuvelo’s own tax minimization strategies.

Utilization of Nuvelo’s net operating loss and research and development credit carryforwards were subject to an annual limitation under the “change in ownership” provisions of the Internal Revenue Code of 1986 and similar state law provisions as a result of certain transactions that Nuvelo entered into prior to 2006. On January 27, 2009, Nuvelo completed its business combination with ARCA. A change of ownership of Nuvelo per IRC Section 382 occurred, and accordingly, ARCA’s ability to utilize these carryforwards has been substantially reduced.

On January 1, 2007, Nuvelo adopted the provisions of FASB Interpretation No. 48, “ Accounting for Uncertainty in Income Taxes , an interpretation of FASB Statement No. 109 ” (FIN 48). FIN 48 requires that a

position taken or expected to be taken in a tax return be recognized in the financial statements when it is more likely than not (i.e. a likelihood of more than 50%) that the position would be sustained upon examination by tax authorities. A recognized tax position is then measured at the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement.

Recent Accounting Pronouncements

In September 2006, the FASB issued Statement 157, “ Fair Value Measurements ” (SFAS 157). SFAS 157 establishes a framework for measuring fair value by providing a standard definition of fair value as it applies to assets and liabilities. SFAS 157, which does not require any new fair value measurements, clarifies the application of other accounting pronouncements that require or permit fair value measurements. The effective date for the Company was January 1, 2008. However, in February 2008, the FASB issued FASB Staff Position No. FAS 157-2, “ Effective Date of FASB Statement No. 157” (FSP 157-2), which delays the effective date of SFAS 157 for all nonfinancial assets and nonfinancial liabilities, except items that are recognized or disclosed at fair value on a recurring basis (at least annually), until fiscal years beginning after November 15, 2008. ARCA is evaluating the impact of adopting SFAS 157 and FSP 157-2 on its consolidated financial statements.

In December 2007, the FASB issued SFAS 141R, which replaces SFAS 141. SFAS 141R requires the acquirer of a business to recognize and measure the identifiable assets acquired, the liabilities assumed, and any non-controlling interest in the acquiree at fair value on the acquisition date. SFAS 141R also requires that transactions costs related to the business combination be expensed as incurred and that changes in accounting for business combination related deferred tax asset valuation allowances and income tax uncertainties after the measurement period be recognized as current period income tax expense. SFAS 141R applies prospectively to business combinations for which the acquisition date is on or after the beginning of the first annual reporting period beginning on or after December 15, 2008. The effective date for Nuvelo was January 1, 2009. ARCA will account for the reverse merger with Nuvelo in accordance with the provisions of SFAS 141R.

In December 2007, the FASB ratified the consensus reached by the EITF on EITF Issue 07-1, “ Accounting for Collaborative Arrangements ” (EITF 07-1). EITF 07-1 requires collaborators to present the results of activities for which they act as the principal on a gross basis and report any payments received from (made to) other collaborators based on other applicable GAAP or, in the absence of other applicable GAAP, based on analogy to authoritative accounting literature or a reasonable, rational, and consistently applied accounting policy election. The effective date for Nuvelo was January 1, 2009. ARCA has not yet determined the impact of EITF 07-1 on its consolidated financial statements.

Off-Balance Sheet Arrangements

Nuvelo had not participated in any transactions with unconsolidated entities, such as special purpose entities, which would have been established for the purpose of facilitating off-balance sheet arrangements.

Indemnifications

In the ordinary course of business, Nuvelo entered into contractual arrangements under which Nuvelo agreed to indemnify certain parties from any losses incurred relating to the services they performed on Nuvelo’s behalf or for losses arising from certain events as defined within the particular contract. Such indemnification obligations may not be subject to maximum loss clauses. Historically, payments made related to these indemnifications had been insignificant. In addition, Nuvelo had entered into indemnity agreements with each of its directors and officers. Such indemnity agreements contain provisions, which are in some respects broader than the specific indemnification provisions contained in Delaware law. Nuvelo also maintained an insurance policy for its directors and executive officers insuring against certain liabilities arising in their capacities as such.

Item 7A.

Quantitative and Qualitative Disclosures About Market Risk

Not applicable.

Item 8.

Financial Statements and Supplementary Data


		Page
Report of Ernst & Young LLP, Independent Registered Public Accounting Firm		63

Consolidated Balance Sheets as of December 31, 2008 and 2007		64

Consolidated Statements of Operations for the years ended December 31, 2008 and 2007		65

Consolidated Statements of Stockholders’ Equity for the years ended December 31, 2008 and 2007		66

Consolidated Statements of Cash Flows for the years ended December 31, 2008 and 2007		67

Notes to Consolidated Financial Statements		68

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Board of Directors and Stockholders of ARCA biopharma, Inc., formerly known as Nuvelo, Inc.:

We have audited the accompanying consolidated balance sheets of ARCA biopharma, Inc., formerly known as Nuvelo, Inc., as of December 31, 2008 and 2007, and the related consolidated statements of operations, stockholders’ equity, and cash flows for the years then ended. These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. We were not engaged to perform an audit of the Company’s internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the consolidated financial position of ARCA biopharma, Inc., formerly known as Nuvelo, Inc., at December 31, 2008 and 2007, and the consolidated results of its operations and its cash flows for the years then ended, in conformity with U.S. generally accepted accounting principles.

/s/ Ernst & Young LLP

Palo Alto, California

March 25, 2009

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

CONSOLIDATED BALANCE SHEETS


	As of December 31,
	2008			2007
	(In thousands, except share and per share information)
ASSETS
Cash and cash equivalents	$	35,891		$	32,061
Marketable securities		15,081			65,506
Collaboration receivable		441			588
Other current assets		715			1,831

Total current assets		52,128			99,986
Restricted cash		6,000			6,000
Property and equipment, net		6,833			8,906
Goodwill		—			4,671
Other assets		1,084			1,120

Total assets	$	66,045		$	120,683

LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	$	1,262		$	2,307
Accrued compensation and employee benefits		876			2,350
Accrued clinical trial and drug manufacturing costs		1,124			3,232
Current portion of deferred revenue		250			250
Current portion of deferred rent		1,459			1,400
Current portion of accrued facility exit costs		6,007			7,389
Other current liabilities		368			1,259

Total current liabilities		11,346			18,187
Non-current portion of deferred revenue		813			16,063
Non-current portion of deferred rent		4,138			5,597
Non-current portion of accrued facility exit costs		7,164			13,098
Other liabilities		76			79

Total liabilities		23,537			53,024

Commitments and contingencies (Notes 8 and 14)

Stockholders’ equity:
Preferred stock, par value $0.001; 5,000,000 shares authorized; none issued and outstanding as of December 31, 2008 and 2007		—			—
Common stock, par value $0.001; 100,000,000 shares authorized; 2,686,957 and 2,671,076 issued and outstanding as of December 31, 2008 and 2007, respectively		3			3
Additional paid-in capital		542,930			538,120
Accumulated other comprehensive income		11			49
Accumulated deficit		(500,436	)		(470,513	)

Total stockholders’ equity		42,508			67,659

Total liabilities and stockholders’ equity	$	66,045		$	120,683

Note:

The above consolidated financial statements are those of Nuvelo, Inc. prior to the merger with ARCA biopharma, Inc.

See accompanying Notes to Consolidated Financial Statements.

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

CONSOLIDATED STATEMENTS OF OPERATIONS


	Year Ended December 31,
	2008			2007
	(In thousands, except per share data)
Contract revenues	$	15,251		$	46,861
Operating expenses:
Research and development		27,764			42,654
General and administrative		14,939			20,762
Restructuring		2,470			2,336
Facility exit costs		(1,342	)		—
Impairment of goodwill		4,671			—

Total operating expenses		48,502			65,752

Operating loss		(33,251	)		(18,891	)
Interest income, net		2,428			6,590
Other income		900			—

Net loss	$	(29,923	)	$	(12,301	)

Basic and diluted net loss per share	$	(11.17	)	$	(4.61	)

Weighted average shares used in computing basic and diluted net loss per share		2,679			2,667

Note:

The above consolidated financial statements are those of Nuvelo, Inc. prior to the merger with ARCA biopharma, Inc.

See accompanying Notes to Consolidated Financial Statements.

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

For the Years Ended December 31, 2008 and 2007


				Additional Paid-in Capital		Accumulated Other Comprehensive Income (Loss)			Accumulated Deficit			Total Stockholders’ Equity
	Common Stock
	Share	Amount
	(in thousands)
Balance at December 31, 2006	2,657	$	3	$	528,042	$	10		$	(458,212	)	$	69,843

Components of comprehensive loss:
Net loss	—		—		—		—			(12,301	)		(12,301	)
Change in unrealized gains or losses on available-for-sale securities	—		—		—		45			—			45
Change in unrealized gains or losses on hedging instruments	—		—		—		(6	)		—			(6	)

Comprehensive loss													(12,262	)
Issuance of common stock upon exercise of stock options and under employee stock purchase plan	9		—		426		—			—			426
Issuance of common stock upon cashless exercise of warrants	5		—		—		—			—			—
Stock-based compensation expense	—		—		9,652		—			—			9,652

Balance at December 31, 2007	2,671		3		538,120		49			(470,513	)		67,659

Components of comprehensive loss:
Net loss	—		—		—		—			(29,923	)		(29,923	)
Change in unrealized gains or losses on available-for-sale securities	—		—		—		(38	)		—			(38	)

Comprehensive loss													(29,961	)
Issuance of common stock under employee stock purchase plan and upon vesting of restricted stock units	16		—		201		—			—			201
Stock-based compensation expense	—		—		4,609		—			—			4,609

Balance at December 31, 2008	2,687	$	3	$	542,930	$	11		$	(500,436	)	$	42,508

Note:

The above consolidated financial statements are those of Nuvelo, Inc. prior to the merger with ARCA biopharma, Inc.

See accompanying Notes to Consolidated Financial Statements.

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

CONSOLIDATED STATEMENTS OF CASH FLOWS


	Year Ended December 31,
	2008			2007
	(In thousands)
Cash flows from operating activities:
Net loss	$	(29,923	)	$	(12,301	)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		2,285			2,343
Stock-based compensation expense		4,609			9,652
Non-cash accretion expense and facility exit costs		131			1,915
Impairment of assets		4,671			1,117
Gain on sale of assets		(8	)		(130	)
Changes in operating assets and liabilities:
Collaboration receivable		147			7,971
Other current assets		1,116			2,800
Other assets		36			301
Accounts payable		(1,045	)		(4,140	)
Accrued compensation and employee benefits		(1,474	)		(748	)
Accrued clinical trial and drug manufacturing costs		(2,108	)		(11,183	)
Deferred revenue		(15,250	)		(31,860	)
Deferred rent		(1,400	)		(1,343	)
Accrued facility exit costs		(8,204	)		(8,044	)
Accrued interest		—			(2,172	)
Other current and non-current liabilities		(91	)		(136	)

Net cash used in operating activities		(46,508	)		(45,958	)

Cash flows from investing activities:
Maturities of marketable securities		94,996			143,936
Purchases of marketable securities		(44,609	)		(116,606	)
Increase in restricted cash		—			(6,000	)
Purchases of property and equipment		(222	)		(381	)
Proceeds from sale of assets		18			136

Net cash provided by investing activities		50,183			21,085

Cash flows from financing activities:
Proceeds from issuance of common stock upon exercise of stock options and under employee stock purchase plan		201			426
Payments on related party line of credit		—			(2,292	)
Payments on bank loans		—			(1,492	)
Payments on capital lease obligations		(46	)		(43	)

Net cash provided by (used in) financing activities		155			(3,401	)

Net increase (decrease) in cash and cash equivalents		3,830			(28,274	)
Cash and cash equivalents at beginning of year		32,061			60,335

Cash and cash equivalents at end of year	$	35,891		$	32,061

Supplemental disclosures of cash flow information:
Interest paid	$	5		$	2,312

Note:

The above consolidated financial statements are those of Nuvelo, Inc. prior to the merger with ARCA biopharma, Inc.

See accompanying Notes to Consolidated Financial Statements.

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Organization and Summary of Significant Accounting Policies

Organization

Nuvelo, Inc. (“Nuvelo”) was incorporated as “Hyseq, Inc.” in Illinois in 1992 and reincorporated in Nevada in 1993. On January 31, 2003, it merged with Variagenics, Inc., a publicly traded Delaware corporation based in Massachusetts, and, in connection with the merger, changed its name to “Nuvelo, Inc.” On March 25, 2004, Nuvelo was reincorporated from Nevada to Delaware.

On January 27, 2009, Nuvelo completed its business combination with ARCA biopharma, Inc. (“ARCA”) in accordance with the terms of the Agreement and Plan of Merger and Reorganization, dated September 24, 2008, by and among Nuvelo, Dawn Acquisition Sub, Inc., a wholly-owned subsidiary of Nuvelo (“Merger Sub”), and ARCA, which was amended on October 28, 2008 (as amended, the “Merger Agreement”). Pursuant to the Merger Agreement, Merger Sub merged with and into ARCA, with ARCA continuing after the merger as the surviving corporation and a wholly-owned subsidiary of Nuvelo. Immediately following the merger, Nuvelo changed its name to ARCA biopharma, Inc. All references herein to “Nuvelo” refer to Nuvelo prior to the completion of the merger and the name change. See Note 2 for further discussion of the merger.

Prior to the merger, Nuvelo was a biopharmaceutical company engaged in the discovery, development and commercialization of novel drugs for acute cardiovascular disease, cancer and other debilitating medical conditions.

Reverse Stock Split

On January 23, 2009, Nuvelo’s stockholders approved an amendment to Nuvelo’s amended and restated certificate of incorporation to effect a reverse stock split of the issued and outstanding shares of Nuvelo’s common stock. Pursuant to the approval by the stockholders, Nuvelo’s board of directors approved the reverse stock split at a ratio of 20-to-1. The reverse stock split became effective after the close of the markets on January 27, 2009.

All share and per share amounts for all periods presented in the consolidated financial statements and notes have been adjusted retroactively to reflect the effect of the reverse stock split, except for the par value per share and the number of shares of common stock and preferred stock authorized for issuance, which are not affected by the reverse stock split.

Basis of Presentation and Principles of Consolidation

The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and include the accounts of Nuvelo and its subsidiaries. All inter-company transactions and accounts have been eliminated in consolidation. Since the merger with ARCA was consummated after December 31, 2008, the accompanying consolidated financial statements and notes reflect the results of operations and financial position of Nuvelo prior to the merger, and do not include the results of operations and financial position of ARCA. Because the merger with ARCA will be treated as a reverse merger, with ARCA considered to be acquiring Nuvelo (see Note 2), the results of operations and financial position of Nuvelo as reported herein are not indicative of the future results of operations and financial position of the combined company.

Use of Estimates

Conformity with GAAP requires the use of estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent amounts. Nuvelo based its estimates on historical experience and on assumptions that were believed to be reasonable under the circumstances, the results of which formed the basis for the judgments made about the carrying values of assets and liabilities that were not readily apparent from other sources. Future results may differ from these estimates. Nuvelo believed significant judgment was involved in evaluating whether alternative future use existed for materials and equipment acquired for use in research and development, in estimating goodwill and long-lived asset impairment, facility exit costs, clinical trial accruals, stock-based compensation, income taxes and in determining revenue recognition.

Liquidity

Nuvelo’s primary sources of liquidity were from financing activities and collaboration receipts. Nuvelo’s primary uses of capital resources were to fund operating activities, including research, clinical development and drug manufacturing expenses, license payments, and spending on capital items.

In order to fund the commercialization of Gencaro, if approved, and to continue development of the current product pipeline, ARCA will need to seek access to the public or private debt and equity markets. Should additional capital not be available to ARCA in the near term, or not be available on acceptable terms, ARCA will not be able to meet its cash requirements under its current operating plan, and therefore will need to reduce its planned expenditures, perhaps significantly, to preserve cash. If necessary, ARCA will implement, beginning as early as the third quarter of 2009, appropriate plans and measures to reduce operating expenses and preserve its cash such that it can continue operations through at least December 31, 2009.

Concentration Risk

Nuvelo was relying on a number of sole-source service providers and suppliers to manufacture bulk drug substance, fill and finish its drug product candidates, and label and package them, and Nuvelo did not have long-term supply agreements with these third-party manufacturers. If these service providers and suppliers are unable to produce the drug product candidates in the quantities and with the quality required, if and when they are needed, ARCA could incur significant additional expenses and efforts to complete its ongoing and anticipated clinical trials.

Cash Equivalents and Marketable Securities

Cash equivalents consisted of money market funds and debt securities with maturities of 90 days or less at the time of purchase. Nuvelo considered its investments in marketable debt securities, which have consisted of U.S. Treasury, U.S. government agency, corporate debt and asset-backed securities, as available for use in current operations. Accordingly, Nuvelo classified these investments as short-term, even though the stated maturity date may be more than one year from the current balance sheet date. Nuvelo invested its excess cash in securities with strong ratings and has established guidelines relative to diversification and maturity with the objective of maintaining safety of principal and liquidity.

Nuvelo classified all cash equivalents and marketable securities as available-for-sale securities, as defined by Statement of Financial Accounting Standards No. 115, “Accounting for Certain Investments in Debt and Equity Securities,” and recorded investments at fair value. Unrealized holding gains and losses on available-for-sale securities, net of any tax effect, were excluded from earnings and were reported in accumulated other comprehensive income (loss), a separate component of stockholders’ equity, until realized. The specific identification method was utilized to calculate the cost to determine realized gains and losses from the sale of available-for-sale securities. Realized gains and losses and declines in value judged to be other than temporary were included in interest income in the statements of operations.

Restricted Cash

Restricted cash represented a certificate of deposit used to collateralize a letter of credit as required by the lease agreement for the unoccupied facility in Sunnyvale, California. See Note 6, Facility Exit Costs, for discussion of the related lease commitment, and Note 8, Commitments, for discussion of the letter of credit arrangement.

Property and Equipment

Property and equipment were recorded at cost less accumulated depreciation. Depreciation expense was calculated using the straight-line method over the estimated useful lives of the assets. Leasehold improvements were related to Nuvelo’s office space in San Carlos, California. The lease term on this office space is seven years. Leasehold improvements were amortized over the shorter of the estimated useful lives of the assets or the lease term. Maintenance and repairs were charged to expenses as incurred. Estimated useful lives were as follows:


Category		Estimated Useful Lives
Leasehold improvements		Shorter of lease term or economic life
Furniture and equipment		Five years
Computer software and equipment		Two to three years

Goodwill and Other Long-Lived Assets—Impairment Assessments

Nuvelo assessed goodwill for impairment in accordance with Statement of Financial Accounting Standards No. 142, “ Goodwill and other Intangible Assets ” (SFAS 142), which requires that goodwill be tested for impairment at the “reporting unit level” (“reporting unit”) at least annually and more frequently upon the occurrence of certain events, as defined by SFAS 142. Consistent with Nuvelo’s determination that it had only one reporting segment, it had determined that there was only one reporting unit. Nuvelo had tested goodwill for impairment in the annual impairment test on October 31 ^st and also reviewed for signs of impairment on a quarterly basis, using the two-step process required by SFAS 142. See Note 5 for further discussion of the goodwill impairment tests performed in 2007 and 2008.

In accordance with Statement of Financial Accounting Standards No. 144, “ Accounting for Impairment or Disposal of Long-Lived Assets, ” Nuvelo evaluated long-lived assets, other than goodwill, for impairment whenever events or changes in circumstances indicated that the carrying value of an asset might not be recoverable based on expected undiscounted cash flows attributable to that asset. The amount of any impairment was measured as the difference between the carrying value and the fair value of the impaired asset. In June 2007, Nuvelo recorded a $1.1 million charge related to an impairment of software implementation costs that were previously capitalized and deemed not recoverable, as it determined that the likelihood of completing the software implementation is remote. The $1.1 million charge was included in general and administrative expenses for the year ended December 31, 2007.

Exit and Disposal Activities

Nuvelo recorded costs and liabilities associated with exit and disposal activities, as defined in Statement of Financial Accounting Standards No. 146, “Accounting for Costs Associated with Exit or Disposal Activities” (SFAS 146), at fair value in the period the liability was incurred. SFAS 146 requires that the estimated future cash flows to be used in the fair value calculation be discounted using a credit-adjusted risk-free interest rate and that such interest rate shall have a maturity date that approximates the expected timing of future cash flows. Future cash flows related to lease obligations include the effect of sublease rental income and other lease operating expenses. Nuvelo re-evaluated its sublease assumptions on a quarterly basis considering current market data, including vacancy rates and lease activities for similar facilities within the area. In periods subsequent to

initial measurement, changes to a liability resulting from changes to the sublease assumptions were measured using the same credit-adjusted risk-free rate that was applied in the initial period. In addition, accretion of the liability due to the passage of time was recorded as a general and administrative expense.

Fair Value Disclosures

On January 1, 2008, Nuvelo adopted Statement of Financial Accounting Standards No. 157, “ Fair Value Measurements ” (SFAS 157). SFAS 157 establishes a common definition for fair value to be applied to U.S. GAAP requiring use of fair value, establishes a framework for measuring fair value, and expands disclosure about such fair value measurements. In February 2008, the FASB issued FASB Staff Position No. FAS 157-2, “ Effective Date of FASB Statement No. 157” (FSP 157-2), which defers the effective date of SFAS 157 for all nonfinancial assets and nonfinancial liabilities, except items that are recognized or disclosed at fair value on a recurring basis (at least annually), until fiscal years beginning after November 15, 2008. The implementation of SFAS 157 for financial assets and financial liabilities did not have a material impact on Nuvelo’s consolidated financial position and results of operations. ARCA is currently assessing the impact of adopting SFAS 157 for nonfinancial assets and nonfinancial liabilities on its financial position and results of operations.

SFAS 157 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). SFAS 157 classifies the inputs used to measure fair value into the following hierarchy:

Level 1—Unadjusted quoted prices in active markets for identical assets or liabilities

Level 2—Unadjusted quoted prices in active markets for similar assets or liabilities; unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active; or inputs other than quoted prices that are observable for the asset or liability

Level 3—Unobservable inputs for the asset or liability

The following table represents Nuvelo’s fair value hierarchy for its financial assets (cash equivalents and marketable securities) measured at fair value on a recurring basis as of December 31, 2008 (in thousands):


	Level 1		Level 2		Level 3		Total
Money market fund	$	34,935	$	—	$	—	$	34,935
Corporate debt securities		—		15,081		—		15,081

Total	$	34,935	$	15,081	$	—	$	50,016

The money market fund, which is expected to maintain a net asset value of $1 per share, was categorized in Level 1 of the fair value hierarchy. Corporate debt securities were categorized in Level 2 of the fair value hierarchy. The fair value of these securities was generally based on pricing models which took into consideration market prices of identical or similar securities from multiple sources and the securities’ accreted balance on the reporting day.

Statement of Financial Accounting Standards No. 159, “ The Fair Value Option for Financial Assets and Financial Liabilities, ” allows entities to voluntarily choose, at specified election dates, to measure many financial instruments and certain other items at fair value that are not currently required to be measured at fair value. To date, Nuvelo has not elected this fair value option for any assets or liabilities.

Revenue Recognition

Nuvelo recognized revenue in accordance with Staff Accounting Bulletin No. 104, “Revenue Recognition,” when (i) persuasive evidence of an arrangement existed, (ii) delivery has occurred or services have been rendered, (iii) the price was fixed and determinable, and (iv) collectibility was reasonably assured. In situations

where there were no continuing performance obligations, or continuing obligations were perfunctory or inconsequential, up-front non-refundable fees were recognized as revenues on the effective date of the related agreement. Up-front non-refundable licensing fees that required continuing involvement in the form of development, manufacturing or other commercialization efforts by Nuvelo were recognized as revenue ratably over the performance period.

Nuvelo evaluated revenue from agreements that had multiple elements to determine whether the components of the arrangement represented separate units of accounting as defined in Emerging Issues Task Force (EITF) Issue No. 00-21, “Revenue Arrangements with Multiple Deliverables” (EITF 00-21). To recognize revenue for a delivered item in a multiple element arrangement, EITF 00-21 requires that the delivered items have value to the customer on a stand-alone basis, there is objective and reliable evidence of fair value of the undelivered items, and delivery of any undelivered items is probable and within Nuvelo’s control if delivered items have a general right of return.

Clinical Trial and Drug Manufacturing Expenses

Costs related to clinical trial and drug manufacturing activities were based upon estimates of the services received and related expenses incurred by contract research organizations (CROs), clinical study sites, drug manufacturers, collaboration partners, laboratories, consultants, or otherwise. Related contracts varied significantly in length, and could be for a fixed amount, a variable amount based on actual costs incurred, capped at a certain limit, or for a combination of these elements. Activity levels were monitored through communications with the CROs and other vendors, including detailed invoices and task completion review, analysis of expenses against budgeted amounts, and pre-approval of any changes in scope of the services to be performed. Certain significant vendors would also provide an estimate of costs incurred but not invoiced on a periodic basis. Expenses related to the CROs and clinical study sites were primarily based on patient enrollment or progress made against specified milestones or targets in each period.

In accordance with Statement of Financial Accounting Standards No. 2, “Accounting for Research and Development Costs,” Nuvelo capitalized clinical trial drug manufacturing costs as “clinical trial supplies,” a current asset on the balance sheet, as long as there were alternative future uses for the related clinical trial drug material in other indications not currently being studied. During 2008 and 2007, Nuvelo determined that there were no alternative future uses for all current drug supplies and that all expenditures related to clinical trial supplies were charged to expense as incurred.

On January 1, 2008, Nuvelo adopted EITF Issue No. 07-3, “ Accounting for Nonrefundable Advance Payments for Goods or Services Received for Use in Future Research and Development Activities ” (EITF 07-3). EITF 07-3 requires that an entity defer and capitalize nonrefundable advance payments made for research and development activities until the related goods are delivered or the related services are performed. The adoption of EITF 07-3 did not have a material effect on Nuvelo’s consolidated financial position and results of operations.

Stock-based Compensation

Nuvelo used the Black-Scholes option-pricing model as it believed that it was the most appropriate fair-value method for its stock-based awards. The Black-Scholes option-pricing model requires assumptions to be made for the expected term of the awards, expected volatility of Nuvelo’s stock price, risk-free interest rates and expected dividend yields. Nuvelo then amortized compensation cost for awards expected to vest over the related

vesting periods. For options granted prior to January 1, 2006, Nuvelo continued to use the graded-vested (multiple-option) method for expense attribution. For options granted after January 1, 2006, Nuvelo was using the straight-line (single-option) method for expense attribution, estimates forfeitures based on historical data and only recognized expense for those shares expected to vest. Adjustments to the forfeiture rate were made if actual forfeitures differed from previous estimates.

For all option grants, Nuvelo considered historical data, including post-vesting termination behavior, and the contractual term to estimate future exercises and cancellations, and therefore the expected term of each option. The expected volatility was based on a combination of historic and implied volatility of Nuvelo’s common stock. The risk-free interest rate assumptions were based on the yield of U.S. Treasury instruments with similar durations as the expected term of the related awards. The expected dividend yield assumption was based on Nuvelo’s historic and expected dividend payouts.

Nuvelo accounted for stock-based compensation expense for non-employee awards based on the fair values estimated using the Black-Scholes model on the date of grant and re-measured at each reporting date until vested, in compliance with EITF Issue No. 96-18, “Accounting for Equity Instruments That Are Issued to Other Than Employees for Acquiring, or in Conjunction with Selling, Goods or Services.” Nuvelo was using the straight-line method to expense the value associated with non-employee awards over the expected service period.

The fair values of employee stock options granted under Nuvelo’s stock option plans during the periods presented were estimated at the date of grant using the Black-Scholes model with the following assumptions and had the following estimated weighted-average grant date fair values per share:


	Year Ended December 31,
	2008			2007
Assumptions:
Expected term		4.63 years			4.94 years
Expected volatility		0.95			0.88
Risk-free interest rate		2.78	%		4.65	%
Expected dividend yield		—			—
Weighted-average grant date fair value per share	$	21.62		$	49.40

The fair values of purchase rights granted under Nuvelo’s employee stock purchase plan during the periods presented were estimated at the date of grant using the Black-Scholes model with the following assumptions and had the following estimated weighted-average grant date fair values per share:


	Year Ended December 31,
	2008			2007
Assumptions:
Expected term		0.25 years			0.25 years
Expected volatility		0.98			0.84
Risk-free interest rate		1.77	%		4.51	%
Expected dividend yield		—			—
Weighted-average grant date fair value per share	$	6.06		$	18.80

Income Taxes

Income taxes were accounted for under the liability method pursuant to Statement of Financial Accounting Standards No. 109, “ Accounting for Income Taxes ” (SFAS 109). Under SFAS 109, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to

apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded to reduce deferred income tax assets to an amount that is more likely than not to be realized.

On January 1, 2007, Nuvelo adopted the provisions of FASB Interpretation No. 48, “Accounting for Uncertainty in Income Taxes—An Interpretation of FASB Statement No. 109” (FIN 48). FIN 48 provides detailed guidance for the financial statement recognition, measurement and disclosure of uncertain tax positions recognized in the financial statements in accordance with SFAS 109. Tax positions must meet a “more-likely- than-not” recognition threshold at the effective date to be recognized upon the adoption of FIN 48 and in subsequent periods. The adoption of FIN 48 did not have a material impact on Nuvelo’s results of operations or financial position.

Net Loss Per Share

Basic and diluted net loss per share are presented in conformity with Statement of Financial Accounting Standards No. 128, “ Earnings Per Share ” (SFAS 128), for all periods presented. In accordance with SFAS 128, basic and diluted net loss per share was computed using the weighted average number of shares of common stock outstanding during the period. In 2008 and 2007, Nuvelo excluded the following outstanding shares of common stock equivalents, as they were anti-dilutive (in thousands):


	December 31,
	2008	2007
Stock options and restricted stock units	279	337
Warrants	43	43

	322	380

Accumulated Other Comprehensive Income

As of December 31, 2008 and 2007, accumulated other comprehensive income consisted of unrealized gain on available-for-sale securities, net of any related tax effects, of $11,000 and $49,000, respectively.

Reclassification

Certain prior period amounts have been reclassified to conform to the current period’s presentation, including accounts payable and other current liabilities in the balance sheets and the statements of cash flows, as well as common stock and additional paid-in capital in the balance sheets and the statements of stockholders’ equity as a result of the reverse stock split discussed above. These reclassifications did not have any effect on the working capital, total liabilities or total stockholders’ equity.

Recent Accounting Pronouncements

In September 2006, the FASB issued Statement 157, “ Fair Value Measurements ” (SFAS 157). SFAS 157 establishes a framework for measuring fair value by providing a standard definition of fair value as it applies to assets and liabilities. SFAS 157, which does not require any new fair value measurements, clarifies the application of other accounting pronouncements that require or permit fair value measurements. The effective date for Nuvelo was January 1, 2008. However, in February 2008, the FASB issued FASB Staff Position No. FAS 157-2, “ Effective Date of FASB Statement No. 157” (FSP 157-2), which defers the effective date of SFAS 157 for all nonfinancial assets and nonfinancial liabilities, except items that are recognized or disclosed at fair value on a recurring basis (at least annually), until fiscal years beginning after November 15, 2008. ARCA is evaluating the impact of adopting SFAS 157 and FSP 157-2 on its financial statements.

In December 2007, the FASB issued Statement 141 (Revised 2007), “ Business Combinations ” (SFAS 141R), which replaces SFAS 141. SFAS 141R requires the acquirer of a business to recognize and measure the identifiable assets acquired, the liabilities assumed, and any non-controlling interest in the acquiree at fair value on the acquisition date. SFAS 141R also requires that transactions costs related to the business combination be expensed as incurred and that changes in accounting for business combination related deferred tax asset valuation allowances and income tax uncertainties after the measurement period be recognized as current period income tax expense. SFAS 141R applies prospectively to business combinations for which the acquisition date is on or after the beginning of the first annual reporting period beginning on or after December 15, 2008. The effective date for Nuvelo was January 1, 2009. ARCA will account for the reverse merger with Nuvelo in accordance with the provisions of SFAS 141R (see Note 2).

2. Merger with ARCA biopharma, Inc.

As discussed in Note 1, on January 27, 2009, Nuvelo completed its business combination with ARCA in accordance with the terms of the Merger Agreement, which was entered into by and among Nuvelo, Merger Sub and ARCA on September 24, 2008 and was amended on October 28, 2008. Pursuant to the Merger Agreement, Merger Sub merged with and into ARCA, with ARCA continuing after the merger as the surviving corporation and a wholly-owned subsidiary of Nuvelo. Immediately following the merger, Nuvelo changed its name to ARCA biopharma, Inc., and ARCA’s common stock began trading on the Nasdaq Global Market under a new symbol “ABIO” starting January 28, 2009.

Under the terms of the Merger Agreement, holders of ARCA capital stock prior to the merger were entitled to receive shares of post-merger ARCA common stock, such that Nuvelo stockholders were expected to own approximately 33% of the common stock of the combined company immediately after the merger and ARCA stockholders, together with holders of ARCA’s options and warrants, were expected to own or had the right to acquire approximately 67% of the common stock of the combined company immediately after the merger, after giving effect to the issuance of shares pursuant to outstanding options and warrants primarily on the treasury stock method. The merger is intended to qualify for federal income tax purposes as a tax-free reorganization under the provisions of Section 368(a) of the U.S. Internal Revenue Code of 1986, as amended.

The merger will be treated by ARCA as a reverse merger and accounted for as a business combination using the purchase method of accounting in accordance with SFAS 141R. For accounting purposes, ARCA is considered to have acquired Nuvelo in the merger, as the stockholders of ARCA prior to the merger now have a controlling interest in the combined company and ARCA’s management is the management of the combined company.

In connection with the merger, approximately 26 of Nuvelo’s employees were terminated in January 2009, and a substantial majority of the remaining employees are retained for a transition period of up to 12 weeks. Total termination benefits related to employees terminated in January 2009 and those on a transition plan were estimated to be $5.0 million.

3. Financial Instruments

Available-for-sale Investments

The cost and fair value of Nuvelo’s available-for-sale investments as of December 31, 2008 and 2007 were as follows (in thousands):


	December 31, 2008
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Money market fund	$	34,935	$	—	$	—		$	34,935
Corporate debt securities		15,070		43		(32	)		15,081

	$	50,005	$	43	$	(32	)	$	50,016

Reported as:
Cash equivalents								$	34,935
Marketable securities									15,081

								$	50,016


	December 31, 2007
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Corporate debt securities	$	78,521	$	47	$	(16	)	$	78,552
Asset-backed securities		9,936		18		—			9,954
Money market funds		8,243		—		—			8,243

	$	96,700	$	65	$	(16	)	$	96,749

Reported as:
Cash equivalents								$	31,243
Marketable securities									65,506

								$	96,749

The following is a summary of amortized cost and estimated fair value of available-for-sale investments by contract maturity (in thousands):


	December 31, 2008				December 31, 2007
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in less than one year	$	50,005	$	50,016	$	94,724	$	94,754
Due in more than one year		—		—		1,976		1,995

Total	$	50,005	$	50,016	$	96,700	$	96,749

The following is a summary of available-for-sale investments with unrealized losses and their related fair value by the period of time each investment has been in an unrealized loss position (in thousands):


	December 31, 2008					December 31, 2007
	Unrealized Losses			Estimated Fair Value		Unrealized Losses			Estimated Fair Value
Unrealized loss position for less than one year	$	(32	)	$	5,338	$	(16	)	$	35,236

Due to the short maturities of investments, the type and quality of security held, the relatively small size of unrealized losses compared to fair value, the short duration of such unrealized losses, and Nuvelo’s intent and ability to hold these investments for a period of time sufficient to allow for any anticipated recovery in market value, Nuvelo believed these unrealized losses to be temporary in nature.

Fair Value of Other Financial Instruments

The carrying amount of other financial instruments, including cash and accrued liabilities, approximated fair value due to their short maturities. As of December 31, 2008 and 2007, Nuvelo did not have any debt or foreign exchange forward contracts outstanding.

4. Property and Equipment, Net

Property and equipment, net, consisted of the following (in thousands):


	December 31,
	2008			2007
Leasehold improvements	$	10,472		$	10,458
Machinery, equipment and furniture		5,848			6,132
Computers and software		2,312			2,264

		18,632			18,854
Accumulated depreciation and amortization		(11,799	)		(9,948	)

	$	6,833		$	8,906

5. Goodwill

Nuvelo tested goodwill for impairment using a fair value approach at the reporting unit level on an annual basis or when events indicated that the carrying value of the asset might be impaired in accordance with SFAS 142. Consistent with the determination that Nuvelo had only one reporting segment, it had determined that there was only one reporting unit and, therefore, goodwill was tested at the entity level. Nuvelo had elected October 31 ^st as its measurement date. Nuvelo completed its last annual goodwill test as of October 31, 2007, and no impairments were recognized.

After Nuvelo announced its decision to discontinue alfimeprase clinical development in 2008 (see Note 7, Restructuring), it experienced a significant decline of its stock price. Nuvelo management determined that Nuvelo’s fair value was lower than the carrying value of its net assets and that its goodwill was impaired. As a result, Nuvelo proceeded to perform the second step of the goodwill impairment test in order to determine the implied fair value of its goodwill and compare it to the carrying value of goodwill. The activities in the second step included valuing the tangible and intangible assets and liabilities of Nuvelo based on their fair value and determining the implied goodwill based upon the difference between the fair value of the reporting unit and the net fair values of identified tangible and intangible assets and liabilities. Based on the results of the second step

of calculating the implied goodwill, Nuvelo recorded an impairment charge of the full balance of goodwill totaling $4.7 million.

6. Facility Exit Costs

In December 2006, Nuvelo approved a plan to exit a 139,000-square-foot leased facility in Sunnyvale, California (the Sunnyvale facility) and restore it for potential sublease. The term of the lease for the facility expires on May 31, 2011. On December 31, 2006, Nuvelo exited the Sunnyvale facility and recorded a liability of $26.6 million to reflect the estimated fair value of future lease-related payments less estimated net income from sublease rental. Future lease-related payments are scheduled to be made periodically until the lease expires.

The balance of accrued facility exit costs represented the value of the lease liability based on assumptions regarding the vacancy period, sublease terms, and the probability of subleasing this space. The estimates and assumptions were re-evaluated each quarter and were based upon current market data, including vacancy rates and lease activities for similar facilities within the area.

As of March 31, 2008, Nuvelo determined that the likelihood of subleasing the Sunnyvale facility during the remainder of the lease term had become remote and, therefore, recorded a $1.5 million charge to reflect such change in the sublease assumption. Nuvelo continued to actively market the facility for sublease. In December 2008, Nuvelo entered into a sublease agreement, pursuant to which the sublease term commenced on March 1, 2009 and ends on May 31, 2011. Accordingly, Nuvelo recorded a credit of $2.1 million in its statement of operations in December 2008, to reflect the change in estimated fair value of the remaining lease obligations after taking into consideration future cash flows from the sublease agreement. As a result of the changes in the sublease assumption in 2008, Nuvelo recorded a net credit of $0.6 million, or $0.22 per share, in its statement of operations, under the caption “Facility exit costs,” for the year ended December 31, 2008.

The following table summarizes the activities related to accrued facility exit costs for the years ended December 31, 2008 and 2007 (in thousands):


Balance as of December 31, 2006	$	26,616
Amounts paid during the period		(8,044	)
Non-cash accretion		1,915

Balance as of December 31, 2007	$	20,487
Amounts paid during the period		(8,204	)
Non-cash accretion		1,473
Net change in fair value due to changes in sublease assumption		(585	)

Balance as of December 31, 2008	$	13,171

The non-cash accretion expense of $1.5 million and $1.9 million was included in general and administrative expenses for the years ended December 31, 2008 and 2007, respectively.

Nuvelo had recorded an accrual of $0.8 million for facility restoration obligation related to the Sunnyvale facility. In connection with the execution of the sublease agreement in December 2008, the landlord of the Sunnyvale facility agreed to release Nuvelo from this facility restoration obligation. As a result, Nuvelo reversed this accrual and recorded a credit of $0.8 million in its statement of operations under the caption “Facility exit costs” in December 2008.

7. Restructuring

with the restructuring, Nuvelo reduced its workforce by approximately 19% and recorded a restructuring expense of $2.5 million, including $1.3 million of termination benefits and $1.2 million of non-cash stock-based compensation expense, for the year ended December 31, 2008. As of December 31, 2008, $0.2 million of termination benefits remained unpaid and were classified under accrued compensation and employee benefits in the balance sheet.

On August 1, 2007, Nuvelo announced a reduction in its workforce by approximately 30% to realign its organization to focus on core development programs that it believed would produce nearest-term proof-of-concept data. In addition, Nuvelo suspended development of rNAPc2 in all indications including cancer and acute coronary syndromes. Nuvelo had completed the restructuring plan and recorded a restructuring expense of $2.3 million, including $1.4 million of termination benefits and $0.9 million of non-cash stock-based compensation expense, for the year ended December 31, 2007. Of the $1.4 million termination benefits, $1.0 million was paid in 2007 and the remaining balance was paid in 2008.

8. Commitments

In January 2005, Nuvelo entered into a seven-year facility lease agreement for 61,826 square feet of space in San Carlos, California, at $2.35 per square foot per month, subject to annual increases of $0.07 per square foot per month. Nuvelo used this facility for its headquarters prior to the merger. The lease term commenced on September 1, 2005, and contains an option to cancel after five years upon payment of certain amounts specified in the lease, two options to extend the lease for five additional years, each at 95% of the then-current fair market rental rate (but not less than the existing rental rate), rights of first refusal over all vacant space in the building during the first two years of the lease, and an expansion option for a specified amount of space. The lease contains a tenant improvement allowance of $8.9 million, which was fully utilized in 2005 and recorded to leasehold improvements and deferred rent, with the respective balances being charged to depreciation and credited to rent expense over the lease term. The rent expense for the lease on the San Carlos facility was being recognized as expense on a straight-line basis. In March 2006, the lease on this property was amended to provide for the exercise of the expansion option over 7,624 square feet of rentable space. The amendment allows for a tenant improvement allowance of $1.0 million, which was fully utilized in 2006, and the related lease rental payments commenced in August 2006. Currently, approximately 6,754 square feet of space in the San Carlos facility are subleased by a subtenant. The term of the sublease, which started in February 2008 and expires in January 2011, can be extended by the subtenant for three additional periods of one year each, subject to certain conditions contained in the sublease agreement.

The lease for the Sunnyvale facility, which expires on May 31, 2011, requires a letter of credit issued to the facility’s landlord in the amount of $6.0 million. The letter of credit is being collateralized by a certificate of deposit of the same amount, which was recorded as restricted cash in the balance sheet. As of December 31, 2006, Nuvelo ceased use of the Sunnyvale facility, as it was no longer required for its business (see Note 6, Facility Exit Costs).

In December 2008, Nuvelo entered into a sublease agreement for its Sunnyvale facility. The term of the sublease commenced on March 1, 2009 and ends on May 31, 2011. The sublease agreement requires the subtenant to pay a monthly base rent of $57,000, except during the first four months of the term, and a substantial majority of the facility operating expenses charged by the facility’s landlord.

As of December 31, 2008, future minimum rental payments and sublease rentals under non-cancelable operating leases were as follows (in thousands):


Years Ending December 31,
2009	$	8,329
2010		8,628
2011		4,979
2012		1,539

Total future minimum rental payments		23,475
Less aggregate future minimum rentals to be received from subleases		(1,854	)

	$	21,621

Rent expense before sublease rentals was $0.7 million for each of the years ended December 31, 2008 and 2007. Total sublease rentals were $0.2 million in 2008, and there were no sublease rentals in 2007.

9. Stockholders’ Equity and Stock-based Compensation

Warrants

As of December 31, 2008, warrants to purchase 42,511 shares of common stock were outstanding and exercisable at exercise prices ranging from $241.44 to $497.40, with a weighted average exercise price per share of $391.38. These warrants, which were granted as part of various financing and business agreements, expire at various times between January 2009 and February 2011. Warrants were recorded in additional paid-in capital at their estimated fair market value at the date of grant using the Black-Scholes option-pricing model.

Stock Plans

On March 14, 2007, Nuvelo’s 2004 Equity Incentive Plan and Employee Stock Purchase Plan were amended to increase the number of shares available for issuance under the plans by 100,000 and 25,000 shares, respectively. On May 31, 2007, the increases for the plans were approved by Nuvelo’s stockholders.

Nuvelo’s stock plans have outstanding grants of stock awards to employees, directors or consultants. In general, the plans authorize the grant of stock options that vest at rates set by the Board of Directors or the Compensation Committee thereof. Generally, stock options granted by Nuvelo prior to the merger under the employee stock plans become exercisable at a rate of 25% per year for a period of four years from date of grant and have a maximum term of ten years. The exercise prices of stock options under employee stock plans generally meet the following criteria: the exercise price of incentive stock options must be at least 100% of the fair market value on the grant date and exercise price of options granted to 10% (or greater) stockholders must be at least 110% of the fair market value on the grant date.

In May 2004, Nuvelo adopted the 2004 Equity Incentive Plan (2004 Plan) to authorize the grant of stock options (including indexed options), stock appreciation rights, restricted stock purchase rights, restricted stock bonuses, restricted stock units, performance shares, performance units and deferred stock units. Under the 2004 Plan, awards may be granted to employees, directors and consultants of Nuvelo, except for incentive stock options, which may be granted only to employees. The 2004 Plan supersedes all prior stock plans (detailed below), and no new awards will be granted under these prior stock plans. As a result of the adoption of the 2004 Plan, all shares previously reserved for issuance under the prior stock plans and remaining for grant are now reserved for issuance under the 2004 Plan. Additionally, shares outstanding under the prior stock plans that are subject to options that expire or otherwise are forfeited become reserved for issuance under the 2004 Plan. As of December 31, 2008, options to purchase 235,807 shares and 1,365 restricted stock units were outstanding under the 2004 Plan, and 328,217 shares were reserved for future awards.

Nuvelo’s other stock plans under which options remained outstanding as of December 31, 2008 are the 1995 Employee Stock Option Plan, the Non-Employee Director Stock Option Plan and the 2002 Equity Incentive Plan. As of December 31, 2008, options to purchase 20,249 shares were outstanding under these stock plans. Additionally, as of December 31, 2008, options to purchase 21,969 shares granted outside of any of Nuvelo’s stock plans were outstanding.

In December 2004, Nuvelo’s Board of Directors approved an Executive Change in Control and Severance Benefit Plan for executive officers and other eligible employees, which was amended and restated in May 2005 and again in August 2007 (Severance Plan). The purpose of the Severance Plan is to provide for the payment of severance benefits and/or change in control benefits to certain eligible employees, and the Severance Plan supersedes and replaces any change in control and/or severance plans adopted previously. The Severance Plan provides that, upon a change in control of Nuvelo as defined under the Severance Plan, all Nuvelo stock options and stock awards held by a plan participant will become fully vested. Such shares held by a plan participant will also become fully vested if the participant is terminated without cause or constructively terminated within one month preceding a change in control. In addition, if a participant is terminated without cause or constructively terminated outside the context of change in control, he or she shall be immediately credited with an additional year of vesting with respect to Nuvelo stock options and stock awards held. The merger with ARCA in January 2009 qualified as a change in control as defined under the Severance Plan. As a result, unvested options and restricted stock units that were held by Nuvelo’s executive officers and one other eligible employee to purchase a total of approximately 39,300 shares became fully vested upon the consummation of the merger.

Under Nuvelo’s employee stock purchase plan (ESPP), eligible employees may elect to purchase shares of Nuvelo’s common stock through payroll deductions at a price equal to the lower of 85% of the fair market value of the stock as of the first or last business day of each three-month period. As of December 31, 2008, there were 11,351 shares available for issuance under the ESPP. During 2008 and 2007, Nuvelo issued 14,986 shares and 8,875 shares of its common stock under the ESPP at a weighted average price per share of $13.39 and $47.40, respectively.

Stock-based Compensation Expense—Stock Options, Restricted Stock Units and ESPP

Stock-based compensation expense related to employees’ stock options, restricted stock units and ESPP purchase rights was as follows (in thousands):


	Year Ended December 31,
	2008		2007
Research and development	$	337	$	3,712
General and administrative		3,035		5,008
Restructuring		1,237		926

Total	$	4,609	$	9,646

Nuvelo terminated two executives in connection with each of its reductions in force announced in March 2008 and August 2007 (see Note 7, Restructuring). These former executives were entitled to a 12-month acceleration in vesting of their stock options in accordance with the Severance Plan. For the years ended December 31, 2008 and 2007, Nuvelo recorded stock-based compensation expense of $1.2 million and $0.9 million, respectively, as a result of the acceleration in vesting of executives’ stock options and classified the expense as part of restructuring costs.

Stock-based compensation expense related to non-employees was negligible in 2008 and 2007.

Nuvelo did not recognize any tax benefit related to employee stock-based compensation cost, as a result of the full valuation allowance on its net deferred tax assets.

A summary of Nuvelo’s stock option activities for the years ended December 31, 2008 and 2007, and related information as of December 31, 2008, was as follows:


	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
					(In years)	(In thousands)
Options outstanding at December 31, 2006	398,083		$	327.00
Granted	79,887			69.60
Exercised	(60	)		82.20
Forfeited or expired	(144,807	)		215.20

Options outstanding at December 31, 2007	333,103			314.00
Granted	65,398			30.09
Exercised	—			—
Forfeited or expired	(120,476	)		227.43
Balances at December 31, 2008:

Options outstanding	278,025		$	284.59	5.32	$	—

Options vested and expected to vest	255,255		$	298.22	5.17	$	—

Options exercisable	213,353		$	334.06	4.79	$	—

Employees’ options are generally vested over a four-year period. In 2007, 65,387 options that were granted to employees as part of the employee retention program vest over a three-year period.

For the years ended December 31, 2008 and 2007, the weighed average grant date fair value of options granted was $21.62 and $49.40 per share, respectively. The total intrinsic value of options exercised in 2007 was negligible, and no options were exercised in 2008. As of December 31, 2008, the unamortized compensation expense related to unvested options, excluding estimated forfeitures, was $7.4 million, and the weighted-average period over which compensation expense related to these options was expected to be recognized was 1.84 years.

The following table summarizes information about stock options outstanding and exercisable as of December 31, 2008:


	Options Outstanding				Options Exercisable
Range of Exercise Prices	Number of Shares	Weighted Average Remaining Contractual Term	Weighted Average Exercise Price		Number of Shares	Weighted Average Exercise Price
		(In years)
$ 13.50 – $ 31.30	42,186	7.44	$	29.26	13,415	$	25.60
33.20 – 81.90	41,243	6.36		70.24	29,720		72.06
89.50 – 179.20	27,304	4.88		147.90	26,013		148.80
183.30 – 183.30	46,036	4.96		183.30	39,792		183.30
184.20 – 203.50	59,324	4.60		198.76	53,893		198.80
222.19 – 1,901.28	61,932	4.34		819.01	50,520		928.52

	278,025	5.32		284.59	213,353		334.06

As of December 31, 2007, 225,604 options were exercisable at a weighted average exercise price of $370.40.

A summary of Nuvelo’s restricted stock unit activity for the years ended December 31, 2008 and 2007, was as follows:


	Number of Units		Aggregate Intrinsic Value
			(In thousands)
Units unvested at December 31, 2006	—
Granted	9,150
Vested	—
Forfeited	(4,850	)

Units unvested at December 31, 2007	4,300
Granted	—
Vested	(1,437	)
Forfeited	(1,498	)
Balances at December 31, 2008:

Units unvested	1,365		$	8

Units vested and expected to vest	897		$	5

Units exercisable	—		$	—

All restricted stock units granted in 2007 have a grant date fair value of $70.80 per unit and a three-year vesting period during which one-third of the units vest at the anniversary date of the grant. No restricted stock units were granted in 2008 or prior to 2007. Restricted stock units granted under the 2004 Plan have no exercise price and have a fair value equal to the average of the high and low prices of Nuvelo’s common stock on the date of grant, in accordance with Nuvelo’s stock award pricing practice. For the year ended December 31, 2008, the fair value of restricted stock units vested was $45,000. No restricted stock unit was vested in 2007. As of December 31, 2008, the unamortized compensation expense related to unvested restricted stock units, excluding estimated forfeitures, was $0.2 million, and the weighted average period over which compensation expense related to these restricted stock units was expected to be recognized was 1.09 years.

10. Collaborative Agreements

Archemix

In July 2006, Nuvelo entered into a collaboration agreement with Archemix Corporation. Under the agreement, Archemix is responsible for the discovery of short-acting aptamers targeting the coagulation cascade for use in acute cardiovascular procedures, and Nuvelo was responsible for development and worldwide commercialization of these product candidates. In August 2006, Nuvelo made an upfront license fee payment to Archemix of $4.0 million, and it is also funding at least $5.25 million of Archemix’s research over the first three years of the agreement. Archemix may receive payments totaling up to $35.0 million per development compound on the achievement of specified development and regulatory milestones, along with potential royalty payments based on sales of licensed compounds. In February 2008, Nuvelo paid Archemix a $1.0 million milestone fee that was accrued upon dosing of the first patient in the Phase I trial for NU172. If ARCA enrolls the first patient in a Phase II trial of NU172, which may occur in 2009, ARCA is obligated to pay Archemix a $3.0 million milestone fee. At the initiation of the first Phase III study for any licensed compound, Archemix has the option to elect to participate in profits from sales of the compound by funding its pro rata share of prior and future product development and commercialization expenses, in lieu of receiving milestone payments and royalties with respect to that compound. In addition, ARCA is obligated to purchase Archemix common stock having a value equal to the lesser of $10.0 million or 15% of the shares issued by Archemix in a qualified public offering of Archemix stock occurring within five years of the effective date of the 2006 collaboration agreement.

Kirin

In March 2005, Nuvelo entered into a collaboration agreement with Kyowa Hakko Kirin Company, Limited for the development and commercialization of NU206. In accordance with the terms of this agreement, Nuvelo received a $2.0 million upfront cash payment from Kirin in April 2005, which was deferred and is being recognized on a straight-line basis over the related performance period through 2013. Nuvelo agreed to lead worldwide development, manufacturing and commercialization of the compound. All operating expenses and any profits related to the development and commercialization of NU206 are being shared 60% by Nuvelo and 40% by Kirin. If this agreement is terminated, or Kirin or ARCA elects under certain circumstances to no longer actively participate in the collaboration, the relationship with respect to NU206 will convert from an expense and profit-sharing structure to a royalty-based structure.

Dendreon

Nuvelo obtained exclusive worldwide rights to all indications of rNAPc2 and all other rNAPc molecules owned by Dendreon Corporation as a result of a licensing agreement entered into with them in February 2004. Under the terms of the agreement, Nuvelo paid Dendreon an upfront fee of $4.0 million ($0.5 million in cash and $3.5 million in Nuvelo common stock) in 2004, which was recorded as research and development expense. Future milestone payments to Dendreon could reach as much as $23.5 million if all development and commercialization milestones are achieved. ARCA currently cannot predict if or when any of these milestones will be achieved. If rNAPc2 is commercialized, ARCA will also be responsible for paying royalties to Dendreon depending on sales of rNAPc2. In 2007, Nuvelo suspended its clinical development of rNAPc2, which could impact the license with Dendreon.

Amgen

In October 2004, Nuvelo obtained worldwide rights to develop and commercialize alfimeprase from Amgen Inc., in exchange for the future payment to Amgen of future development milestones and royalties. Future milestone payments under the license agreement could total as much as $35.0 million. In 2008, Nuvelo discontinued development of alfimeprase. ARCA cannot predict if or when any of these additional milestones will be achieved.

Bayer

In June 2007, Nuvelo and Bayer Healthcare AG terminated their January 2006 license and collaboration agreement for the development and commercialization of alfimeprase. As part of the termination agreement with Bayer, Nuvelo agreed to waive Bayer’s obligation to provide Nuvelo 12 months’ notice of termination in consideration of Bayer’s agreement to pay Nuvelo a lump sum of $15.0 million. Nuvelo also granted Bayer the option to reacquire rights to alfimeprase upon the initiation of a pivotal stroke trial or upon Nuvelo’s public announcement that it is discontinuing further development of alfimeprase in the stroke indications. The notice period during which Bayer could exercise the option would begin upon Nuvelo making certain information available to Bayer and last for 30 days after delivery of the information.

As a result of the termination of the collaboration agreement with Bayer, Nuvelo recognized in June 2007 the remaining unamortized balance of the $50.0 million up-front license fee received from Bayer in January 2006, which totaled approximately $44.9 million. The up-front license fee had been recorded as deferred revenue upon receipt and was being recognized on a straight-line basis over the performance period under the agreement, originally estimated to be through September 2020.

On March 17, 2008, Nuvelo announced its decision to discontinue further clinical development of alfimeprase, including the programs in catheter occlusion and acute ischemic stroke. In April 2008, Nuvelo provided the information to Bayer as required by the termination agreement. The $15.0 million termination

payment, which had been recorded as deferred revenue, was recognized as revenue in May 2008 upon the expiration of the notice period.

Under the original terminated agreement, Nuvelo was responsible for 60% of any costs for alfimeprase global development programs, and Bayer was responsible for the remaining 40%. Pursuant to this cost-sharing arrangement, a total of $3.0 million was billed to Bayer for Nuvelo’s alfimeprase-related global development spending for the year ended December 31, 2007, and was recorded as an offset to research and development expenses in the statements of operations. The cost-sharing arrangement ended when the collaboration agreement was terminated in June 2007.

11. Note Receivable

In connection with the sale of its subsidiary, Callida Genomics, Inc. (Callida), to SBH Genomics, Inc. (SBH) on December 3, 2004, Nuvelo received a convertible promissory note from SBH with a principal amount of $0.9 million. The promissory note was convertible into SBH’s preferred shares if SBH raised at least $2.0 million in venture capital financing within four years after the date of the sale. If SBH failed to raise at least $2.0 million in venture capital financing within this period, the promissory note became due and payable. No interest or principal was payable on the promissory note for the two years through December 3, 2006. Simple interest of prime rate plus 1% per annum was payable in the third and fourth years on a quarterly basis. Prime rate was set as of the second anniversary of the sale and adjusted on the third anniversary. Interest income was credited to income in the period received. Nuvelo had initially assessed the value of the promissory note to be zero due to its assessment of the probability of collection. In December 2008, Nuvelo received a full payment of the $0.9 million promissory note and recorded $0.9 million as other income in the statement of operations.

12. Income Taxes

The reconciliations between the amounts computed by applying the U.S. federal statutory tax rate of 34% to loss from continuing operations and the actual provision for income taxes were as follows (in thousands):


	Year Ended December 31,
	2008			2007
Loss from continuing operations	$	(29,923	)	$	(12,301	)

Federal tax benefit at statutory rate	$	(10,174	)	$	(4,182	)
Current year net operating losses and temporary differences, for which a full valuation allowance is recorded		6,923			2,225
State taxes, net of federal benefit		1			1
Impairment of goodwill		1,588			—
Stock-based compensation		1,061			1,956
Merger-related expenses		601			—

Provision for income taxes	$	—		$	—

Deferred Income Taxes

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets for financial reporting and the amounts used for income tax purposes. Significant components of Nuvelo’s deferred tax assets for federal and state income taxes were as follows (in thousands):


	December 31,
	2008			2007
Deferred tax assets:
Property and equipment	$	3,324		$	3,598
Accruals and reserves		5,914			15,154
Net operating loss carryforwards		151,046			126,503
Research and other tax credit carryforwards		7,354			6,893
Capital loss carryforward—discontinued operations		3,153			3,152
Capitalized research and development costs		10,653			10,846
Stock-based compensation		2,371			1,784
Other		—			7,200

Total deferred tax assets		183,815			175,130
Valuation allowance		(183,815	)		(175,130	)

Deferred tax assets, net of valuation allowance	$	—		$	—

Deferred tax assets were reduced by a valuation allowance, as management believed that it was more likely than not that the deferred tax assets would not be realized. The valuation allowance increased $8.7 million for the year ended December 31, 2008 and decreased by $3.8 million for the year ended December 31, 2007.

Net Operating Loss Carryforwards

The utilization of Nuvelo’s net operating loss carryforwards and tax credit carryforwards are subject to annual limitation due to the ownership changes per the Internal Revenue Code and similar state provisions. Such an annual limitation may result in the expiration of the net operating loss before utilization. In 2007, Nuvelo completed a review of its ownership changes and concluded certain common stock offerings prior to 2006 resulted in ownership changes that triggered a net operating loss carryforward annual limitation. This annual limitation per Section 382 of the Internal Revenue Code results in approximately $119.0 million in net operating loss carryforwards for years up to and including 2005 expiring not utilized. Similarly, approximately $12.0 million of research tax credits will expire unused. Adjusting for the annual limitation, at December 31, 2008, Nuvelo had net operating loss carryforwards for federal income tax purposes of approximately $412.5 million which begin to expire in year 2009, and federal tax credits of approximately $3.0 million which begin to expire in 2026. At December 31, 2008, Nuvelo also had state net operating loss carryforwards of approximately $207.2 million which begin to expire in 2012 and state tax credits of approximately $6.6 million which have no expiration date.

Approximately $13.3 million of the federal net operating losses and $7.2 million of the state net operating losses relate to deductions from stock-based compensation. The benefit from the realization of these losses will be an adjustment to Additional Paid-in Capital.

On December 3, 2004, Nuvelo sold its subsidiaries, Callida and N-Mer. As of December 31, 2008, the related capital loss carryforward was $7.9 million, which will expire in 2009.

As discussed in Note 2, on January 27, 2009, Nuvelo completed its business combination with ARCA. A change in ownership of Nuvelo per Section 382 occurred, and accordingly, ARCA’s ability to utilize the net operating loss carryforwards and tax credits has been substantially reduced.

FIN 48

Nuvelo adopted FIN 48 which requires that it recognize the financial statement effects of a tax position when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. No adjustment to Nuvelo’s accumulated deficit was required upon its adoption of FIN 48 on January 1, 2007.

Nuvelo had cumulative unrecognized tax benefit of approximately $6.2 million as of January 1, 2007. The following table summarizes the activity related to the unrecognized tax benefit for the years ended December 31, 2008 and 2007 (in thousands):


Balance at January 1, 2007	$	6,159
Increase related to current year tax position		1,075

Balance at December 31, 2007		7,234
Increase related to current year tax position		576
Decrease related to prior year tax position		(488	)

Balance at December 31, 2008	$	7,322

As of December 31, 2008 and 2007, the cumulative unrecognized tax benefit was netted against deferred tax assets with a full valuation allowance or other fully reserved amounts, and if recognized there would be no effect on Nuvelo’s effective tax rate. The amount of existing unrecognized tax benefit was not expected to significantly increase or decrease within the next 12 months.

Nuvelo recognized interest accrued and penalties related to unrecognized tax benefits in general and administrative expense. During the years ended December 31, 2008 and 2007, Nuvelo recognized an insignificant amount in interest and penalties.

Nuvelo is currently open to audit under the statute of limitations by the Internal Revenue Service and the appropriate state income taxing authorities for all years due to the net loss carryovers from those years.

13. Segment and Revenue Concentration Data

Segment Data

Nuvelo was engaged in the discovery, development and commercialization of novel acute cardiovascular and cancer therapies. Nuvelo had only one reportable segment. The reportable segment reflected Nuvelo’s structure, reporting responsibilities to the chief executive officer and the nature of the products under development.

Revenue Concentration Data

Revenues from collaborative agreements or other sources representing 10% or more of total revenues in each period were as follows:

*	less than 10% of total revenues

14. Legal Matters

On December 4, 2008, the Court issued an order dismissing plaintiff’s complaint, and granting leave to amend. On January 23, 2009, plaintiffs filed an amended complaint, alleging similar claims. Based on the Court’s December 4, 2008 order, and plaintiff’s amended complaint, ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by its insurance provider. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the case is not finally dismissed, or if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

In addition, on or about December 6, 2001, Variagenics, Inc. was sued in a complaint filed in the United States District Court for the Southern District of New York naming it and certain of its officers and underwriters as defendants. The complaint purportedly is filed on behalf of persons purchasing Variagenics’ stock between July 21, 2000 and December 6, 2000, and alleges violations of Sections 11, 12(a)(2) and 15 of the Securities Act of 1933, as amended and Section 10(b) of the Securities Exchange Act of 1934, as amended, and Rule 10b-5 promulgated thereunder. The complaint alleges that, in connection with Variagenics’ July 21, 2000 initial public offering, or IPO, the defendants failed to disclose additional and excessive commissions purportedly solicited by and paid to the underwriter defendants in exchange for allocating shares of Variagenics’ stock to preferred customers and alleged agreements among the underwriter defendants and preferred customers tying the allocation of IPO shares to agreements to make additional aftermarket purchases at predetermined prices. Plaintiffs claim that the failure to disclose these alleged arrangements made Variagenics’ registration statement on Form S-1 filed with the SEC in July 2000 and the prospectus, a part of the registration statement, materially false and misleading. Plaintiffs seek unspecified damages. On or about April 19, 2002, an amended complaint was filed which makes essentially the same allegations. On or about July 15, 2002, Variagenics and the individuals filed a motion to dismiss. Nuvelo is involved in this litigation as a result of Nuvelo’s merger with Variagenics in January 2003. On July 16, 2003, Nuvelo’s board of directors approved a settlement proposal initiated by the plaintiffs. However, because of a recent court ruling, the settlement class, as defined in the settlement papers, is no longer feasible. While a new complaint has not been filed against Nuvelo, there are several “focus” cases against other issuers in which new complaints have been filed. Defendant issuers in the “focus” cases filed motions to dismiss the new complaints. On March 26, 2008, the District Court issued an order granting in part and denying in part the “focus” issuers motions to dismiss. The “focus” issuers had been advised that plaintiffs intended to file new complaints against Nuvelo, but none have been filed yet. ARCA believes that any attorneys’ fees, loss or settlement payment with respect to this suit will be paid by Nuvelo’s insurance provider. However, it is possible that ARCA could be forced to incur material expenses in the litigation if the parties cannot achieve a settlement, and, in the event of an adverse outcome, ARCA’s business could be harmed.

Item 9.

Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Not applicable.

Item 9A(T).

Controls and Procedures

Evaluation of Disclosure Controls and Procedures

Under the supervision and with the participation of management, including our Chief Executive Officer and our Chief Financial Officer, we have evaluated the effectiveness of the design and operation of Nuvelo’s disclosure controls and procedures. Disclosure controls and procedures are controls and procedures that are designed to ensure that information required to be disclosed in our reports filed or submitted under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer have concluded that Nuvelo’s disclosure controls and procedures were effective as of the end of the period covered by this annual report.

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting (as defined in Rules 13a-15(f) and 15(d)-15(f) under the Exchange Act). Our internal control system was designed to provide reasonable assurance to management and our board of directors regarding the preparation and fair presentation of published financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Under the supervision and with the participation of management, including our Chief Executive Officer and Chief Financial Officer, we have assessed the effectiveness of Nuvelo’s internal control over financial reporting as of December 31, 2008. In making our assessment of internal control over financial reporting, we used the criteria issued in the report Internal Control-Integrated Framework by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). We have concluded that Nuvelo’s internal control over financial reporting was effective as of December 31, 2008 based on these criteria.

This annual report does not include an attestation report of the Company’s independent registered public accounting firm regarding internal control over financial reporting. Management’s report was not subject to attestation by the Company’s independent registered public accounting firm pursuant to temporary rules of the SEC that permit the Company to provide only management’s report in this annual report.

Changes in Internal Control over Financial Reporting

During the fourth quarter of 2008, there were no changes in our internal control over financial reporting that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting. Upon completion of the merger transaction on January 27, 2009, Nuvelo’s and ARCA’s operations were combined. As a result of the completion of the merger, we are evaluating our internal control policies and procedures and may make modifications to the design and effectiveness of our internal control policies and procedures.

Limitations on the Effectiveness of Controls

Our management, including the Chief Executive Officer and Chief Financial Officer, does not expect that our disclosure controls and procedures or our internal control over financial reporting will prevent all errors and

all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, within the Company have been detected.

Item 9B.

Other Information

None.

PART III

Item 10.

Directors, Executive Officers and Corporate Governance

The information required by this item is incorporated by reference to “Election of Board of Directors,” “Section 16(a) Beneficial Ownership Reporting Compliance” and “Executive Officers” in our Definitive Proxy Statement to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, relating to our 2009 Annual Meeting of Stockholders.

We have adopted a Code of Business Conduct and Ethics (the “Code of Conduct”) that applies to all of our directors, officers and employees including our principal executive officer, principal financial officer, principal accounting officer and controller. The Code of Conduct is located on our website at www.arcabiopharma.com in the section titled, “Investors,” under the subsection titled, “Corporate Governance.” If we make any substantive amendments to the Code of Conduct or grant any waiver from a provision of the Code of Conduct to any executive officer or director, we intend to disclose the nature of the amendment or waiver on our website. Information found on our website is not incorporated by reference into this report.

Item 11.

Executive Compensation

The response to this item is incorporated by reference to “Executive Compensation” in our Definitive Proxy Statement to be filed pursuant to Regulation 14A under the Exchange Act, relating to our 2009 Annual Meeting of Stockholders.

Item 12.

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

The response to this item, except for Equity Compensation Plan Information disclosed below, is incorporated by reference to “Security Ownership of Certain Beneficial Owners and Management” and “Executive Compensation” in our Definitive Proxy Statement to be filed pursuant to Regulation 14A under the Exchange Act, relating to our 2009 Annual Meeting of Stockholders.

Equity Compensation Plan Information

The following table sets forth information as of December 31, 2008 for all of Nuvelo’s equity compensation plans in existence prior to the merger:


Plan Category	No. of Securities to be Issued Upon Exercise of Outstanding Options, Warrants and Rights (a)	Weighted Average Exercise Price of Outstanding Options, Warrants and Rights (b)		No. of Securities Remaining Available for Future Issuance Under Equity Compensation Plans Excluding Securities Reflected in Column(a) (c)
Plan Category
Equity compensation plans approved by security holders	274,087	$	274.17	339,568
Equity compensation plans not approved by security holders(1)	5,303	$	750.00	—

Total	279,390	$	283.20	339,568

(1)	Consists of option granted to an executive officer of Nuvelo described below which is not required to be and has not been approved by its stockholders.

Non-Stockholder Approved Equity Arrangements

In 2001, Nuvelo granted Dr. Ted W. Love options to purchase shares of common stock in connection with and as an inducement to his commencement of employment with Nuvelo. Specifically, on January 11, 2001,

Nuvelo granted Dr. Love an option to purchase 7,802 shares of common stock at an exercise price of $750.00 per share, the closing price on the date of grant, of which 5,303 remained outstanding as of December 31, 2008. Dr. Love’s employment as the president and chief executive officer of Nuvelo was terminated on January 27, 2009. Dr. Love continues to serve as a member of the board of directors of ARCA after the merger, and his stock options remain exercisable until his service as a board member terminates.

Item 13.

Certain Relationships and Related Transactions, and Director Independence

The response to this item is incorporated by reference to “Certain Relationships and Related Transactions” in our Definitive Proxy Statement to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, relating to our 2009 Annual Meeting of Stockholders.

Item 14.

Principal Accountant Fees and Services

The response to this item is incorporated by reference to “Ratification of Selection of Independent Auditors” in our Definitive Proxy Statement to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, relating to our 2009 Annual Meeting of Stockholders.

PART IV

Item 15.

Exhibits and Financial Statement Schedules

(a) The following documents are filed as part of this Report:

Consolidated financial statements filed as part of this Report are listed under Part II, Item 8, page 62 of this Form 10-K.

No schedules are required because either the required information is not present or is not present in amounts sufficient to require submission of the schedule, or because the information required is included in the consolidated financial statements or the notes thereto.

(b) Exhibits

The following documents are filed as part of this annual report on Form 10-K. The Company will furnish a copy of any exhibit listed to requesting stockholders upon payment of the Company’s reasonable expenses in furnishing those materials.


Exhibit Number		Description
2.1		Agreement and Plan of Merger, dated November 9, 2002, by and among Hyseq, Inc., Vertical Merger Corp. and Variagenics, Inc.(7)

2.2		Agreement and Plan of Merger, dated March 19, 2004, by and between Nuvelo, Inc. and Nuvelo, Inc., a Nevada corporation and Nuvelo, Inc.’s predecessor in interest.(10)

2.3		Stock Purchase Agreement, dated December 3, 2004, between SBH Genomics, Inc., Radoje Drmanac, Snezana Drmanac, Nuvelo, Inc., and Affymetrix, Inc.(13)

2.4		Agreement and Plan of Merger and Reorganization, dated September 24, 2008, among Nuvelo, Inc., Dawn Acquisition Sub, Inc. and ARCA biopharma, Inc.(22)

2.5		Amendment No. 1 to Agreement and Plan of Merger and Reorganization, dated October 28, 2008, by and among Nuvelo, Inc., Dawn Acquisition Sub, Inc. and ARCA biopharma, Inc.(23)

3.1*		Amended and Restated Certificate of Incorporation of the Registrant, as amended.

3.2*		Amended and Restated Bylaws of the Registrant, as amended.

4.1		Form of Common Stock Certificate.(24)

4.2		Certificate of Designations of Series A Junior Participating Preferred Stock. (included as part of Exhibit 3.1)

4.3*		Warrant to Purchase Stock Agreement, dated July 17, 2007, by and between ARCA Discovery, Inc. and Silicon Valley Bank.

4.4*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and SVB Financial Group.

4.5*		Warrant to Purchase Stock Agreement, dated August 19, 2008, by and between ARCA biopharma, Inc. and Silicon Valley Bank.

4.6*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and SVB Financial Group.

4.7*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Boulder Ventures IV, L.P.

4.8*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Boulder Ventures IV, L.P.


Exhibit Number		Description
4.9*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Boulder Ventures IV (Annex), L.P.

4.10*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Boulder Ventures IV (Annex), L.P.

4.11*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and InterWest Partners IX, LP.

4.12*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and InterWest Partners IX, LP.

4.13*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Atlas Venture Fund VII, L.P.

4.14*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Atlas Venture Fund VII, L.P.

4.15*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and The Peierls Foundation, Inc.

4.16*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and The Peierls Foundation, Inc.

4.17*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Skyline Venture Partners Qualified Purchaser Fund IV, L.P.

4.18*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Skyline Venture Partners Qualified Purchaser Fund IV, L.P.

10.1§		Collaboration Agreement, dated March 31, 2005, by and between Kirin Brewery Company Ltd. and Nuvelo, Inc.(15)

10.2§		Amended and Restated Collaboration and License Agreement, dated July 31, 2006, by and between Nuvelo, Inc. and Archemix Corp.(18)

10.3		Lease, dated April 30, 2001, by and between The Irvine Company and Hyseq, Inc.(4)

10.4		First Amendment to Lease, dated August 1, 2002, by and between The Irvine Company and Hyseq, Inc.(6)

10.5		Second Amendment to Lease, dated October 21, 2003, by and between The Irvine Company and Nuvelo, Inc.(9)

10.6		Third Amendment to Lease, dated September 15, 2005, by and between The Irvine Company and Nuvelo, Inc.(17)

10.7		Lease Agreement, dated January 11, 2005, by and between Nuvelo, Inc. and BMR-201 Industrial Road LLC.(14)

10.8		First Amendment to Lease, dated May 10, 2005, by and between BMR-201 Industrial Road LLC and Nuvelo, Inc.(16)

10.9*		Lease, dated February 8, 2008, by and between ARCA Discovery, Inc. and Arista Place, LLC.

10.10*		Loan and Security Agreement, dated July 17, 2007, by and between ARCA biopharma, Inc. and Silicon Valley Bank.

10.11*		First Amendment to Loan and Security Agreement, dated January 21, 2009, by and between ARCA biopharma, Inc. and Silicon Valley Bank.


Exhibit Number		Description
10.12*		Second Amendment to Loan and Security Agreement, dated March 23, 2009, by and between ARCA biopharma Colorado, Inc. and Silicon Valley Bank.

10.13*		Note and Warrant Purchase Agreement, dated September 24, 2008.

10.14*		Amendment to Note and Warrant Purchase Agreement, dated October 10, 2008.

10.15†		Stock Option Plan, as amended.(2)

10.16†		Non-Employee Director Stock Option Plan, as amended.(3)

10.17†		Form of Non-Stockholder Approved Stock Option Agreement for Officers.(5)

10.18†		Nuvelo, Inc. 2002 Equity Incentive Plan.(8)

10.19†		Amended and Restated Nuvelo, Inc. 2004 Equity Incentive Plan.(19)

10.20†		Form of Notice of Grant of Stock Option under Nuvelo, Inc. 2004 Equity Incentive Plan.(11)

10.21†		Form of Nuvelo, Inc. Stock Option Agreement (Single Trigger Acceleration) under Nuvelo, Inc. 2004 Equity Incentive Plan.(11)

10.22†		Form of Nuvelo, Inc. Stock Option Agreement (Double Trigger Acceleration) under Nuvelo, Inc. 2004 Equity Incentive Plan.(12)

10.23†		Employee Stock Purchase Plan, as amended and restated on May 31, 2007.(19)

10.24†		ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.25†		Amendment No. 1 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.26†		Amendment No. 2 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.27†		Amendment No. 3 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.28†		Amendment No. 4 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.29†		Amendment No. 5 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.30†		Amendment No. 6 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.31†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Executive Incentive Stock Option Agreement.(24)

10.32†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Non-Executive Incentive Stock Option Agreement.(24)

10.33†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Nonqualified Stock Option Agreement.(24)

10.34†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Partial Acceleration Stock Option Agreement.

10.35†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of No Acceleration Stock Option Agreement.

10.36†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Director Stock Option Agreement.

10.37†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Notice of Grant of Stock Option.

10.38†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Notice of Director Grant of Stock Option.


Exhibit Number		Description
10.39		Form of Indemnification Agreement between Nuvelo, Inc. and its directors and officers.(1)

10.40†		Nuvelo, Inc. Amended Executive Change in Control and Severance Benefit Plan.(20)

10.41†		Separation Agreement, dated April 14, 2008, by and between Nuvelo, Inc. and Michael D. Levy.(21)

10.42†		Bonuses for Named Executive Officers Approved on January 25, 2008.(21)

10.43†*		Amended and Restated Employment and Retention Agreement, dated June 4, 2008, by and between ARCA biopharma, Inc. and Michael R. Bristow.

10.44†*		Amended and Restated Employment and Retention Agreement, dated July 7, 2008, by and between ARCA biopharma, Inc. and Richard B. Brewer.

10.45†*		Amended and Restated Employment Agreement, dated June 12, 2008, by and between ARCA biopharma, Inc. and Christopher D. Ozeroff.

10.46†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.

10.47†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.

10.48†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.

10.49†		Letter Employment Agreement, dated January 27, 2009 and effective February 2, 2009, by and between ARCA biopharma, Inc. and Lee Bendekgey.(25)

10.50†*		Employment Agreement, dated February 24, 2009, by and between ARCA biopharma, Inc. and Randall St. Laurent.

10.51†*		Employment Agreement, dated February 23, 2009, by and between ARCA biopharma, Inc. and Kathryn E. Falberg.

10.52*		Form of Indemnification Agreement between ARCA biopharma, Inc. and its directors and officers.

21.1*		Subsidiaries of ARCA biopharma, Inc. as of March 24, 2009.

23.1*		Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm.

24.1*		Power of Attorney (included in the signature page hereto).

31.1*		Certification of Chief Executive Officer pursuant to Rule 13a-14(a) or 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

31.2*		Certification of Chief Financial Officer pursuant to Rule 13a-14(a) or 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

32.1*		Certification of Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C. sec. 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

*	Filed herewith.

†	Compensatory plan or agreement.

§	Confidential treatment has been requested for portions of this document, which are omitted and filed separately with the SEC.

(1)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-1, filed on June 12, 1997, as amended, File No. 333-29091.

(2)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-8, filed on May 20, 1998, File No. 333-08978.

(3)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-8, filed on May 20, 1998, File No. 333-53089.

(4)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 8-K, filed on May 21, 2001, File No. 000-22873.

(5)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 10-K/A, filed on May 9, 2002, File No. 000-22873.

(6)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 10-Q, filed on November 8, 2002, File No. 000-22873.

(7)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 8-K, filed on November 12, 2002, File No. 000-22873.

(8)	Previously filed with the SEC as an Appendix to and incorporated herein by reference from Nuvelo, Inc.’s Proxy Statement on Schedule 14A, filed on June 13, 2002, File No. 000-22873.

(9)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 14, 2003, File No. 000-22873.

(10)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on March 26, 2004, File No. 000-22873.

(11)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 20, 2004, File No. 000-22873.

(12)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 9, 2004, File No. 000-22873.

(13)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on December 9, 2004, File No. 000-22873.

(14)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-K, filed on March 16, 2005, File No. 000-22873.

(15)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on May 10, 2005, File No. 000-22873.

(16)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on May 13, 2005, File No. 000-22873.

(17)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 20, 2005, File No. 000-22873.

(18)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 8, 2006, File No. 000-22873.

(19)	Previously filed with the SEC as an Appendix to and incorporated herein by reference from Nuvelo, Inc.’s Proxy Statement on Schedule 14A, filed on April 18, 2007, File No. 000-22873.

(20)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 7, 2007, File No. 000-22873.

(21)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on May 9, 2008, File No. 000-22873.

(22)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 25, 2008, File No. 000-22873.

(23)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on October 29, 2008, File No. 000-22873.

(24)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from ARCA biopharma, Inc.’s Form 8-K, filed on January 28, 2009, File, No. 000-22873.

(25)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from ARCA biopharma, Inc.’s Form 8-K, filed on February 2, 2009, File No. 000-22873.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.


ARCA biopharma, Inc.

By:		/s/ L EE B ENDEKGEY
		Lee Bendekgey Principal Accounting Officer

Date: March 27, 2009

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Richard B. Brewer and Kathryn E. Falberg, and each of them, as his true and lawful attorneys-in-fact and agents, with full power of substitution for him, and in his name in any and all capacities, to sign any and all amendments to this Annual Report on Form 10-K, and to file the same, with exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done therewith, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, and any of them or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed by the following persons on behalf of ARCA biopharma, Inc., in the capacities and on the dates indicated.


Signature	Title	Date

/s/ R ICHARD B. B REWER Richard B. Brewer	President and Chief Executive Officer and Director (Principal Executive Officer)	March 27, 2009

/s/ K ATHRYN E. F ALBERG Kathryn E. Falberg	Chief Financial Officer and Chief Operating Officer (Principal Financial Officer)	March 27, 2009

/s/ L EE B ENDEKGEY Lee Bendekgey	Principal Accounting Officer	March 27, 2009

/s/ M ICHAEL R. B RISTOW Michael R. Bristow	Director	March 27, 2009

/s/ J EAN -F RANCOIS F ORMELA Jean-Francois Formela	Director	March 27, 2009

/s/ J. W ILLIAM F REYTAG J. William Freytag	Director	March 27, 2009

/s/ L INDA G RAIS Linda Grais	Director	March 27, 2009

/s/ T ED W. L OVE Ted W. Love	Director	March 27, 2009


Signature	Title	Date

/s/ D AVID G. L OWE David G. Lowe	Director	March 27, 2009

/s/ M ARY K. P ENDERGAST Mary K. Pendergast	Director	March 27, 2009

/s/ B URTON E. S OBEL Burton E. Sobel	Director	March 27, 2009

/s/ J OHN L. Z ABRISKIE John L. Zabriskie	Director	March 27, 2009

EXHIBIT INDEX


Exhibit Number		Description
2.1		Agreement and Plan of Merger, dated November 9, 2002, by and among Hyseq, Inc., Vertical Merger Corp. and Variagenics, Inc.(7)

2.2		Agreement and Plan of Merger, dated March 19, 2004, by and between Nuvelo, Inc. and Nuvelo, Inc., a Nevada corporation and Nuvelo, Inc.’s predecessor in interest.(10)

2.3		Stock Purchase Agreement, dated December 3, 2004, between SBH Genomics, Inc., Radoje Drmanac, Snezana Drmanac, Nuvelo, Inc., and Affymetrix, Inc.(13)

2.4		Agreement and Plan of Merger and Reorganization, dated September 24, 2008, among Nuvelo, Inc., Dawn Acquisition Sub, Inc. and ARCA biopharma, Inc.(22)

2.5		Amendment No. 1 to Agreement and Plan of Merger and Reorganization, dated October 28, 2008, by and among Nuvelo, Inc., Dawn Acquisition Sub, Inc. and ARCA biopharma, Inc.(23)

3.1*		Amended and Restated Certificate of Incorporation of the Registrant, as amended.

3.2*		Amended and Restated Bylaws of the Registrant, as amended.

4.1		Form of Common Stock Certificate.(24)

4.2		Certificate of Designations of Series A Junior Participating Preferred Stock. (included as part of Exhibit 3.1)

4.3*		Warrant to Purchase Stock Agreement, dated July 17, 2007, by and between ARCA Discovery, Inc. and Silicon Valley Bank.

4.4*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and SVB Financial Group.

4.5*		Warrant to Purchase Stock Agreement, dated August 19, 2008, by and between ARCA biopharma, Inc. and Silicon Valley Bank.

4.6*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and SVB Financial Group.

4.7*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Boulder Ventures IV, L.P.

4.8*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Boulder Ventures IV, L.P.

4.9*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Boulder Ventures IV (Annex), L.P.

4.10*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Boulder Ventures IV (Annex), L.P.

4.11*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and InterWest Partners IX, LP.

4.12*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and InterWest Partners IX, LP.

4.13*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Atlas Venture Fund VII, L.P.

4.14*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Atlas Venture Fund VII, L.P.

4.15*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and The Peierls Foundation, Inc.


Exhibit Number		Description
4.16*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and The Peierls Foundation, Inc.

4.17*		Warrant to Purchase Stock Agreement, dated October 10, 2008, by and between ARCA biopharma, Inc. and Skyline Venture Partners Qualified Purchaser Fund IV, L.P.

4.18*		Amendment No. 1 to Warrant to Purchase Stock Agreement, dated February 19, 2009, by and between ARCA biopharma, Inc. and Skyline Venture Partners Qualified Purchaser Fund IV, L.P.

10.1§		Collaboration Agreement, dated March 31, 2005, by and between Kirin Brewery Company Ltd. and Nuvelo, Inc.(15)

10.2§		Amended and Restated Collaboration and License Agreement, dated July 31, 2006, by and between Nuvelo, Inc. and Archemix Corp.(18)

10.3		Lease, dated April 30, 2001, by and between The Irvine Company and Hyseq, Inc.(4)

10.4		First Amendment to Lease, dated August 1, 2002, by and between The Irvine Company and Hyseq, Inc.(6)

10.5		Second Amendment to Lease, dated October 21, 2003, by and between The Irvine Company and Nuvelo, Inc.(9)

10.6		Third Amendment to Lease, dated September 15, 2005, by and between The Irvine Company and Nuvelo, Inc.(17)

10.7		Lease Agreement, dated January 11, 2005, by and between Nuvelo, Inc. and BMR-201 Industrial Road LLC.(14)

10.8		First Amendment to Lease, dated May 10, 2005, by and between BMR-201 Industrial Road LLC and Nuvelo, Inc.(16)

10.9*		Lease, dated February 8, 2008, by and between ARCA Discovery, Inc. and Arista Place, LLC.

10.10*		Loan and Security Agreement, dated July 17, 2007, by and between ARCA biopharma, Inc. and Silicon Valley Bank.

10.11*		First Amendment to Loan and Security Agreement, dated January 21, 2009, by and between ARCA biopharma, Inc. and Silicon Valley Bank.

10.12*		Second Amendment to Loan and Security Agreement, dated March 23, 2009, by and between ARCA biopharma Colorado, Inc. and Silicon Valley Bank.

10.13*		Note and Warrant Purchase Agreement, dated September 24, 2008.

10.14*		Amendment to Note and Warrant Purchase Agreement, dated October 10, 2008.

10.15†		Stock Option Plan, as amended.(2)

10.16†		Non-Employee Director Stock Option Plan, as amended.(3)

10.17†		Form of Non-Stockholder Approved Stock Option Agreement for Officers.(5)

10.18†		Nuvelo, Inc. 2002 Equity Incentive Plan.(8)

10.19†		Amended and Restated Nuvelo, Inc. 2004 Equity Incentive Plan.(19)

10.20†		Form of Notice of Grant of Stock Option under Nuvelo, Inc. 2004 Equity Incentive Plan.(11)

10.21†		Form of Nuvelo, Inc. Stock Option Agreement (Single Trigger Acceleration) under Nuvelo, Inc. 2004 Equity Incentive Plan.(11)

10.22†		Form of Nuvelo, Inc. Stock Option Agreement (Double Trigger Acceleration) under Nuvelo, Inc. 2004 Equity Incentive Plan.(12)


Exhibit Number		Description
10.23†		Employee Stock Purchase Plan, as amended and restated on May 31, 2007.(19)

10.24†		ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.25†		Amendment No. 1 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.26†		Amendment No. 2 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.27†		Amendment No. 3 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.28†		Amendment No. 4 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.29†		Amendment No. 5 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.30†		Amendment No. 6 to the ARCA Discovery, Inc. 2004 Stock Incentive Plan.(24)

10.31†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Executive Incentive Stock Option Agreement.(24)

10.32†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Non-Executive Incentive Stock Option Agreement.(24)

10.33†		ARCA biopharma, Inc. 2004 Stock Incentive Plan, Form of Nonqualified Stock Option Agreement.(24)

10.34†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Partial Acceleration Stock Option Agreement.

10.35†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of No Acceleration Stock Option Agreement.

10.36†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Director Stock Option Agreement.

10.37†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Notice of Grant of Stock Option.

10.38†*		ARCA biopharma, Inc. 2004 Equity Incentive Plan (f/k/a Nuvelo, Inc. 2004 Equity Incentive Plan), Form of Notice of Director Grant of Stock Option.

10.39		Form of Indemnification Agreement between Nuvelo, Inc. and its directors and officers.(1)

10.40†		Nuvelo, Inc. Amended Executive Change in Control and Severance Benefit Plan.(20)

10.41†		Separation Agreement, dated April 14, 2008, by and between Nuvelo, Inc. and Michael D. Levy.(21)

10.42†		Bonuses for Named Executive Officers Approved on January 25, 2008.(21)

10.43†*		Amended and Restated Employment and Retention Agreement, dated June 4, 2008, by and between ARCA biopharma, Inc. and Michael R. Bristow.

10.44†*		Amended and Restated Employment and Retention Agreement, dated July 7, 2008, by and between ARCA biopharma, Inc. and Richard B. Brewer.

10.45†*		Amended and Restated Employment Agreement, dated June 12, 2008, by and between ARCA biopharma, Inc. and Christopher D. Ozeroff.

10.46†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.

10.47†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.


Exhibit Number		Description
10.48†*		Assignment and Assumption Agreement, dated January 26, 2009, by and between ARCA biopharma, Inc. and ARCA biopharma Colorado, Inc.

10.49†		Letter Employment Agreement, dated January 27, 2009 and effective February 2, 2009, by and between ARCA biopharma, Inc. and Lee Bendekgey.(25)

10.50†*		Employment Agreement, dated February 24, 2009, by and between ARCA biopharma, Inc. and Randall St. Laurent.

10.51†*		Employment Agreement, dated February 23, 2009, by and between ARCA biopharma, Inc. and Kathryn E. Falberg.

10.52*		Form of Indemnification Agreement between ARCA biopharma, Inc. and its directors and officers.

21.1*		Subsidiaries of ARCA biopharma, Inc. as of March 24, 2009.

23.1*		Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm.

24.1*		Power of Attorney (included in the signature page hereto).

31.1*		Certification of Chief Executive Officer pursuant to Rule 13a-14(a) or 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

31.2*		Certification of Chief Financial Officer pursuant to Rule 13a-14(a) or 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

32.1*		Certification of Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C. sec. 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

*	Filed herewith.

†	Compensatory plan or agreement.

§	Confidential treatment has been requested for portions of this document, which are omitted and filed separately with the SEC.

(1)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-1, filed on June 12, 1997, as amended, File No. 333-29091.

(2)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-8, filed on May 20, 1998, File No. 333-08978.

(3)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form S-8, filed on May 20, 1998, File No. 333-53089.

(4)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 8-K, filed on May 21, 2001, File No. 000-22873.

(5)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 10-K/A, filed on May 9, 2002, File No. 000-22873.

(6)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 10-Q, filed on November 8, 2002, File No. 000-22873.

(7)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Hyseq, Inc.’s Form 8-K, filed on November 12, 2002, File No. 000-22873.

(8)	Previously filed with the SEC as an Appendix to and incorporated herein by reference from Nuvelo, Inc.’s Proxy Statement on Schedule 14A, filed on June 13, 2002, File No. 000-22873.

(9)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 14, 2003, File No. 000-22873.

(10)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on March 26, 2004, File No. 000-22873.

(11)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 20, 2004, File No. 000-22873.

(12)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 9, 2004, File No. 000-22873.

(13)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on December 9, 2004, File No. 000-22873.

(14)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-K, filed on March 16, 2005, File No. 000-22873.

(15)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on May 10, 2005, File No. 000-22873.

(16)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on May 13, 2005, File No. 000-22873.

(17)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 20, 2005, File No. 000-22873.

(18)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 8, 2006, File No. 000-22873.

(19)	Previously filed with the SEC as an Appendix to and incorporated herein by reference from Nuvelo, Inc.’s Proxy Statement on Schedule 14A, filed on April 18, 2007, File No. 000-22873.

(20)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on November 7, 2007, File No. 000-22873.

(21)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 10-Q, filed on May 9, 2008, File No. 000-22873.

(22)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on September 25, 2008, File No. 000-22873.

(23)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from Nuvelo, Inc.’s Form 8-K, filed on October 29, 2008, File No. 000-22873.

(24)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from ARCA biopharma, Inc.’s Form 8-K, filed on January 28, 2009, File, No. 000-22873.

(25)	Previously filed with the SEC as an Exhibit to and incorporated herein by reference from ARCA biopharma, Inc.’s Form 8-K, filed on February 2, 2009, File No. 000-22873.

Exhibit 3.1

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

NUVELO MERGER SUB, INC.

Pursuant to Sections 241 and 245 of the

General Corporation Law of the State of Delaware

Nuvelo Merger Sub, Inc., a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), hereby certifies as follows:

1. The original Certificate of Incorporation was filed with the Secretary of State of the State of Delaware on March 16, 2004.

2. This Amended and Restated Certificate of Incorporation restates and integrates and further amends the provisions of the Certificate of Incorporation, and has been duly adopted pursuant to Sections 241 and 245 of the General Corporation Law of the State of Delaware.

3. The entire text of the Amended and Restated Certificate of Incorporation is as follows:

The name of this corporation is Nuvelo, Inc. (the “Corporation”).

II.

The Corporation’s registered office in the State of Delaware is the Corporation Trust Company, Corporation Trust Center, 1209 Orange Street, City of Wilmington, County of New Castle, 19801. The name of its registered agent at such address is The Corporation Trust Company.

III.

The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of Delaware.

IV.

The total number of shares of all classes of stock this Corporation shall have authority to issue is 105,000,000, consisting of 100,000,000 shares of Common Stock, par value $0.001 per share, and 5,000,000 shares of Preferred Stock, par value $0.001 per share. The Preferred Stock may be issued from time to time, in one or more series, each series to be appropriately designated by a distinguishing letter or title, prior to the issue of any shares thereof.

The Board of Directors of the Corporation is hereby authorized to fix or alter the dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions, if any), the redemption price or prices, the liquidation preferences, any other designations, preferences and relative, participating, optional or other special rights, and any qualifications, limitations or restrictions thereof, of any wholly unissued series of Preferred Stock, and the number of shares constituting any such unissued series and the designation thereof, or any of them; and to increase or decrease the number of shares of any series subsequent to the issue of shares of that series, but not below the number of shares of such series then outstanding. In case the number of shares of any series shall be so decreased, the shares constituting such decrease shall resume the status which they had prior to the adoption of the resolution originally fixing the number of shares of such series.

In furtherance and not in limitation of the powers conferred by statute, the Board of Directors of the Corporation is expressly authorized to make, alter or repeal Bylaws of the Corporation. Notwithstanding the foregoing, the Bylaws of the Corporation may be rescinded, altered, amended or repealed in any respect by the affirmative vote of the holders of at least 66 ² / 3 % of the outstanding voting stock of the Corporation, voting together as a single class.

VI.

The Board of Directors of the Corporation shall have that number of directors set out in the Bylaws of the Corporation as adopted or as set from time to time by a duly adopted amendment thereto by the Directors or stockholders of the Corporation. The Board of Directors shall be divided into three classes, as nearly equal in number as possible. The initial classification of directors shall be determined in accordance with a resolution or resolutions adopted by the Board of Directors. The term of office of the first class shall expire at the first annual meeting of stockholders or any special meeting in lieu thereof following January 1, 2004, the term of office of the second class shall expire at the second annual meeting of stockholders or any special meeting in lieu thereof following January 1, 2004 and the term of office of the third class shall expire at the third annual meeting of stockholders or any special meeting in lieu thereof following January 1, 2004. At each annual meeting of stockholders or special meeting in lieu thereof following such initial classification, directors elected to succeed those directors whose terms expire shall be elected for a term of office to expire at the third succeeding annual meeting of the stockholders or special meeting in lieu thereof after their election and until their successors are duly elected and qualified.

Newly created directorships resulting from any increase in the authorized number of directors or any vacancies in the Board of Directors resulting from death, resignation, retirement, disqualification, removal from office or other cause may be filled only by a majority vote of the directors then in office even though less than a quorum, or by a sole remaining director, and not by the stockholders. In the event of any increase or decrease in the authorized number of directors, (a) each director then serving as such shall nevertheless continue as a director of the class of which he or she is a member until the expiration of his or her current term or his or her prior death, retirement, removal or resignation and (b) the newly created or eliminated directorships resulting from such increase or decrease shall if reasonably possible be apportioned

by the Board of Directors among the three classes of directors so as to ensure that no one class has more than one director more than any other class. In the event of a vacancy in the Board of Directors, the remaining directors, except as otherwise provided by law, may exercise the powers of the full Board of Directors until the vacancy is filled. Notwithstanding the foregoing, each director shall serve until his or her successor is duly elected and qualified or until his or her death, resignation or removal. No decrease in the number of directors constituting the Board of Directors shall shorten the term of any incumbent director.

VII.

Elections of directors need not be by written ballot unless otherwise provided in the Bylaws of the Corporation.

VIII.

No action shall be taken by the stockholders except at a duly called annual or special meeting of stockholders. The stockholders may not take action by written consent.

Special meetings of the stockholders of the Corporation for any purpose or purposes may be called at any time by the Board of Directors, or as otherwise set forth in the Bylaws of the Corporation.

An affirmative vote of the holders of shares representing a majority of the outstanding Common Stock shall be required to approve (a) the sale of U.S. Patent 5,202,231, or (b) exclusive license or assignment to a single person or entity, other than a wholly-owned subsidiary, which license or assignment has the same effect as a sale of all rights, title and interest in U.S. Patent 5,202,231.

IX.

To the fullest extent permitted by the Delaware General Corporation Law, as the same exists or as may hereafter be amended, a director of the Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director.

To the fullest extent permitted by law, the Corporation may indemnify and advance indemnification expenses to any person made or threatened to be made a party to an action or proceeding, whether criminal, civil, administrative or investigative, by reason of the fact that he or she, his or her testator or intestate is or was a director, officer or employee of the Corporation or any predecessor of the Corporation, or serves or served at any other enterprise as a director, officer or employee at the request of the Corporation or any predecessor to the Corporation. The Corporation may, to the fullest extent permitted by law, purchase and maintain insurance on behalf of any such director or officer against any liability which may be asserted against him or her and may enter contracts providing for the indemnification of any such person to the fullest extent permitted by law.

Neither any amendment nor repeal of this Article IX, nor the adoption of any provision of this Certificate of Incorporation inconsistent with this Article IX, shall eliminate or reduce the

effect of this Article IX in respect of any matter occurring, or any action or proceeding accruing or arising or that, but for this Article IX, would accrue or arise, prior to such amendment, repeal or adoption of an inconsistent provision.

The Corporation is to have perpetual existence.

XI.

Meetings of stockholders may be held within or without the State of Delaware, as the Bylaws may provide. The books of the Corporation may be kept (subject to any statutory provision) outside the State of Delaware at such place or places as may be designated from time to time by the Board of Directors or in the Bylaws.

XII.

The Corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, by an affirmative vote of the holders of a majority of the voting rights of all classes of stock entitled to vote, provided, however, that no amendment, alteration, change or repeal of any provision requiring the affirmative vote of the holders of more than a majority of the voting rights may be made unless approved by the affirmative vote of such greater number of holders. The affirmative vote of the holders of 66 ² /3% of the voting rights is required to amend, repeal or adopt any provision inconsistent with the provisions of the Certificate of Incorporation relating to: (i) the requirement that all stockholder action be taken only at a duly called annual meeting or special meeting; (ii) the authority and power of the Board of Directors and the procedure required to amend the Corporation’s Bylaws; (iii) the percentage of the shares necessary to amend the Certificate of Incorporation; (iv) the elimination of Directors’ personal liability for monetary damages arising from their negligence and gross negligence; and (v) indemnification of Directors, officers and other persons.

* * *

I, THE UNDERSIGNED, being the sole incorporator of the Corporation, for the purpose of amending the Certificate of Incorporation filed by the undersigned with the Delaware Secretary of State on March 16, 2004 pursuant to the General Corporation Law of the State of Delaware, do make this certificate, herein declaring and certifying that this is my act and deed and the facts herein stated are true, and accordingly have hereunto set my hand this 18th day of March, 2004.

/s/ Linda T. Kingsbury

LINDA T. KINGSBURY

Incorporator

NUVELO, INC.

CERTIFICATE OF DESIGNATIONS

SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

SETTING FORTH

THE POWERS, PREFERENCES, RIGHTS, QUALIFICATIONS,

LIMITATIONS AND RESTRICTIONS OF

SUCH SERIES OF PREFERRED STOCK

Nuvelo, Inc. (the “Corporation”), a corporation organized and existing under the General Corporation Law of the State of Delaware, DOES HEREBY CERTIFY:

That pursuant to the authority conferred upon the Board of Directors by the Corporation’s Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation” ), in accordance with the provisions of Section 151 of the General Corporation Law of the State of Delaware, the Board of Directors of the Corporation, on March 19, 2004, adopted a resolution providing for the issuance of up to 100,000 shares of Series A Junior Participating Preferred Stock, par value $0.001 per share, with the following designations, preferences and relative, participating, optional or other rights and the qualifications, limitations and restrictions:

Series A Junior Participating Preferred Stock :

Section 1. Designation and Amount . The shares of such series shall be designated as Series A Junior Participating Preferred Stock (the “Series A Junior Preferred Stock” ) and the authorized number of shares constituting the Series A Junior Preferred Stock shall be 100,000. Such number of shares may be increased or decreased by resolution of the Board of Directors; provided, that no decrease shall reduce the number of shares of Series A Junior Preferred Stock to a number less than the number of shares then outstanding plus the number of shares reserved for issuance upon the exercise of outstanding options, rights, or warrants or upon the conversion of any outstanding securities issued by the Corporation convertible into Series A Junior Preferred Stock.

Section 2. Dividends and Distributions . (a) Subject to the rights of the holders of any shares of any series of Preferred Stock (or any similar stock) ranking prior and superior to the Series A Junior Preferred Stock with respect to dividends, the holders of shares of Series A Junior Preferred Stock, in preference to the holders of Common Stock, par value $0.001 per share (the “Common Stock” ), of the Corporation, and of any other junior stock, shall be entitled to receive, when, as and if declared by the Board of Directors out of funds legally available for the purpose, quarterly dividends payable in cash on the first day of March, June, September and

December in each year (each such date being referred to herein as a “Quarterly Dividend Payment Date” ), commencing on the first Quarterly Dividend Payment Date after the first issuance of a share or fraction of a share of Series A Junior Preferred Stock, in an amount per share (rounded to the nearest cent) equal to the greater of (a) $1.00 or (b) subject to the provision for adjustment hereinafter set forth, 1,000 times the aggregate per share amount of all cash dividends, and 1,000 times the aggregate per share amount (payable in kind) of all non-cash dividends or other distributions, other than a dividend payable in shares of Common Stock or a subdivision of the outstanding shares of Common Stock (by reclassification or otherwise), declared on the Common Stock since the immediately preceding Quarterly Dividend Payment Date or, with respect to the first Quarterly Dividend Payment Date, since the first issuance of any share or fraction of a share of Series A Junior Preferred Stock. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision, combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the amount to which holders of shares of Series A Junior Preferred Stock were entitled immediately prior to such event under clause (1) of the preceding sentence shall be adjusted by multiplying such amount by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

(b) The Corporation shall declare a dividend or distribution on the Series A Junior Preferred Stock as provided in paragraph (a) of this Section 2 immediately after it declares a dividend or distribution on the Common Stock (other than a dividend payable in shares of Common Stock); provided that, in the event no dividend or distribution shall have been declared on the Common Stock during the period between any Quarterly Dividend Payment Date and the next subsequent Quarterly Dividend Payment Date, a dividend of per share on the Series A Junior Preferred Stock shall nevertheless be payable on such subsequent Quarterly Dividend Payment Date.

(c) Dividends shall begin to accrue and be cumulative on outstanding shares of Series A Junior Preferred Stock from the Quarterly Dividend Payment Date next preceding the date of issue of such shares, unless the date of issue of such shares is prior to the record date for the first Quarterly Dividend Payment Date, in which case dividends on such shares shall begin to accrue from the date of issue of such shares, or unless the date of issue is a Quarterly Dividend Payment Date or is a date after the record date for the determination of holders of shares of Series A Junior Preferred Stock entitled to receive a quarterly dividend and before such Quarterly Dividend Payment Date, in either of which events such dividends shall begin to accrue and be cumulative from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not bear interest Dividends paid on the shares of Series A Junior Preferred Stock in an amount less than the total amount of such dividends at the time accrued and payable on such shares shall be allocated pro rata on a share-by-share basis among all such shares at the time outstanding. The Board of Directors may fix a record date for the determination of holders of shares of Series A Junior Preferred Stock entitled to receive payment of a dividend or distribution declared thereon, which record date shall be not more than 60 days prior to the date fixed for the payment thereof.

Section 3. Voting Rights . The holders of shares of Series A Junior Preferred Stock shall have the following voting rights:

(a) Subject to the provision for adjustment hereinafter set forth, each share of Series A Junior Preferred Stock shall entitle the holder thereof to 1,000 votes on all matters submitted to a vote of the Stockholders of the Corporation. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision, combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, in each such case the number of votes per share to which holders of shares of Series A Junior Preferred Stock were entitled immediately prior to such event shall be adjusted by multiplying such number by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

(b) Except as otherwise provided herein, in any other Certificate of Designations creating a series of Preferred Stock or any similar stock, or by law, the holders of shares of Series A Junior Preferred Stock and the holders of shares of Common Stock and any other capital stock of the Corporation having general voting rights shall vote together as one class on all matters submitted to a vote of Stockholders of the Corporation.

(c) Except as set forth herein, or as otherwise provided by law, holders of Series A Junior Preferred Stock shall have no special voting rights and their consent shall not be required (except to the extent they are entitled to vote with holders of Common Stock as set forth herein) for taking any corporate action.

Section 4. Certain Restrictions . (a) Whenever quarterly dividends or other dividends or distributions payable on the Series A Junior Preferred Stock as provided in Section 2 are in arrears, thereafter and until all accrued and unpaid dividends and distribution, whether or not declared, on shares of Series A Junior Preferred Stock outstanding shall have been paid in full, the Corporation shall not:

(i) declare or pay dividends, or make any other distributions, on any shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the Series A Junior Preferred Stock;

(ii) declare or pay dividends, or make any other distributions, on any shares of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or winding up) with the Series A Junior Preferred Stock, except dividends paid ratably on the Series A Junior Preferred Stock and all such parity stock on which dividends are payable or in arrears in proportion to the total amounts to which the holders of all such shares are then entitled;

(iii) redeem or purchase or otherwise acquire for consideration shares of any stock ranking junior (either as to dividends or upon liquidation, dissolution or winding

up) to the Series A Junior Preferred Stock, provided that the Corporation may at any time redeem, purchase or otherwise acquire shares of any such junior stock in exchange for shares of any stock of the Corporation ranking junior (either as to dividends or upon dissolution, liquidation or winding up) to the Series A Junior Preferred Stock; or

(iv) redeem or purchase or otherwise acquire for consideration any shares of Series A Junior Preferred Stock, or any shares of stock ranking on a parity with the Series A Junior Preferred Stock, except in accordance with a purchase offer made in writing or by publication (as determined by the Board of Directors) to all holders of such shares upon such terms as the Board of Directors, after consideration of the respective annual dividend rates and other relative rights and preferences of the respective series and classes, shall determine in good faith will result in fair and equitable treatment among the respective series or classes.

(b) The Corporation shall not permit any subsidiary of the Corporation to purchase or otherwise acquire for consideration any shares of stock of the Corporation unless the Corporation could, under subsection (a) of this Section 4, purchase or otherwise acquire such shares at such time and in such manner.

Section 5. Reacquired Shares . Any shares of Series A Junior Preferred Stock purchased or otherwise acquired by the Corporation in any manner whatsoever shall be retired and canceled promptly after the acquisition thereof. All such shares shall upon their cancellation become authorized but unissued shares of Preferred Stock of the Corporation and may be reissued as part of a new series of Preferred Stock of the Corporation, subject to the conditions and restrictions on issuance set forth herein, in the Certificate of Incorporation, or in any other Certificate of Designations creating a series of Preferred Stock or any similar stock or as otherwise required by law.

Section 6. Liquidation, Dissolution or Winding Up . Upon any liquidation, dissolution or winding up of the Corporation, no distribution shall be made (1) to the holders of shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the Series A Junior Preferred Stock unless, prior thereto, the holders of shares of Series A Junior Preferred Stock shall have received $1,000 per share, plus an amount equal to accrued and unpaid dividends and distributions thereon, whether or not declared, to the date of such payment, provided that the holders of shares of Series A Junior Preferred Stock shall be entitled to receive an aggregate amount per share, subject to the provision for adjustment hereinafter set forth, equal to 1,000 times the aggregate amount to be distributed per share to holders of shares of Common Stock, or (2) to the holders of share of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or winding up) with the Series A Junior Preferred Stock, except distributions made ratably on the Series A Junior Preferred Stock and all such parity stock in proportion to the total amounts to which the holders of all such shares are entitled upon such liquidation, dissolution or winding up. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision, combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the aggregate

amount to which holders of shares of Series A Junior Preferred Stock were entitled immediately prior to such event under the proviso in clause (1) of the preceding sentence shall be adjusted by multiplying such amount by a fraction the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that are outstanding immediately prior to such event.

Section 7. Consolidation, Merger, etc. In case the Corporation shall enter into any consolidation, merger, combination or other transaction in which the shares of Common Stock are exchanged for or changed into other stock or securities, cash and/or any other property, then in any such case each share of Series A Junior Preferred Stock shall at the same time be similarly exchanged or changed into an amount per share, subject to the provision for adjustment hereinafter set forth, equal to 1,000 times the aggregate amount of stock, securities, cash and/or any other property (payable in kind), as the case may be, into which or for which each shares of Common Stock is changed or exchanged. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision, combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the amount set forth in the preceding sentence with respect to the exchange or change of shares of Series A Junior Preferred Stock shall be adjusted by multiplying such amount by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

Section 8. No Redemption . The shares of Series A Junior Preferred Stock shall not be redeemable.

Section 9. Rank . The Series A Junior Preferred Stock shall rank, with respect to the payment of dividends and the distribution of assets, junior to all series of any other class of the Corporation’s preferred stock, except to the extent that any such other series specifically provides that it shall rank on a parity with or junior to the Series A Junior Preferred Stock.

Section 10. Amendment . The Certificate of Incorporation of the Corporation shall not be amended in any manner which would materially alter or change the powers, preferences or special rights of the Series A Junior Preferred Stock so as to affect them adversely without the affirmative vote of the holders of at least two-thirds of the outstanding shares of Series A Junior Preferred Stock, voting together as a single class.

[Signature Page Follows]

IN WITNESS WHEREOF, the above named officers, acting for and on behalf of Nuvelo, Inc. have hereunto subscribed their names on this 24 ^th day of March, 2004.


NUVELO, INC.

By:		/s/ Ted W. Love
Name:		Ted W. Love
Title:		President

Attest:


By:		/s/ Peter S. Garcia
Name:		Peter S. Garcia
Title:		Secretary

CERTIFICATE OF AMENDMENT TO THE

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

NUVELO, INC.

NUVELO, INC. , a corporation organized and existing under the General Corporation law of the State of Delaware does hereby certify:

ONE: The date of filing the original Certificate of Incorporation of this company with the Secretary of State of the State of Delaware was March 16, 2004 as amended and restated on March 18, 2004.

TWO: The Board of Directors of the Company, acting in accordance with the provisions of Sections 141 and 242 of the General Corporation Law of the State of Delaware, adopted resolutions amending its Amended and Restated Certificate of Incorporation as follows:

Article IV shall be amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:00 p.m. Eastern time, on the date of filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 20 shares of issued Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the then fair value of the Common Stock as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time

into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided, however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

THREE: Thereafter, pursuant to a resolution by the Board of Directors of the Corporation, this Certificate of Amendment was submitted to the stockholders of the corporation for their consideration and was duly adopted and approved in accordance with the provisions of Sections 228 and 242 of the General Corporation Law of the State of Delaware at a special meeting of the stockholders.

IN WITNESS WHEREOF , Nuvelo, Inc. has caused this CERTIFICATE OF AMENDMENT TO THE AMENDED AND RESTATED CERTIFICATE OF INCORPORATION to be signed by its Chairman of the Board of Directors and Chief Executive Officer this 27th day of January, 2009.


NUVELO, INC.

By:		/s/ Ted W. Love, M.D.
		Ted. W. Love, M.D.
		Chairman of the Board of Directors and Chief Executive Officer

CERTIFICATE OF OWNERSHIP AND MERGER

MERGING

ARCA MERGER, INC.

(a Delaware corporation)

WITH AND INTO

NUVELO, INC.

(a Delaware corporation)

(Pursuant to Section 253 of the General Corporation Law

of the State of Delaware)

Nuvelo, Inc., a Delaware corporation (the “ Corporation ”) does hereby certify:

FIRST : That the Corporation is incorporated pursuant to the General Corporation Law of the State of Delaware (the “ Delaware Law ”).

SECOND : That the Corporation owns all of the outstanding shares of each class of the outstanding capital stock of ARCA Merger, Inc., a Delaware corporation (the “ Subsidiary ”).

THIRD : That the Corporation, by the following resolutions of its Board of Directors (the “ Board ”) duly adopted by unanimous written consent on January 27, 2009, determined to merge Subsidiary with and into the Corporation pursuant to Section 253 of the Delaware Law:

WHEREAS, the Corporation owns all of the outstanding shares of each class of the outstanding capital stock of the Subsidiary; and

WHEREAS, the Board has determined that it is fair to, advisable and in the best interests of, the Corporation and its stockholders for the Subsidiary to be merged with and into the Corporation pursuant to Section 253 of the Delaware Law, with the Corporation surviving the merger and assuming all of the Subsidiary’s liabilities and obligations (the “ Merger ”); now, therefore, be it

RESOLVED, the Merger be, and it hereby is, authorized, approved and adopted in all respects;

FURTHER RESOLVED , that, in accordance with Section 103(d) of the Delaware Law, the Merger shall become effective upon the filing of the Certificate of Ownership and Merger with the Secretary of State of the State of Delaware;

FURTHER RESOLVED, that pursuant to Section 253(b) of the Delaware Law, the Board deems it advisable and in the best interest of the Corporation and its stockholders, and hereby approves, a change in the Corporation’s corporate name to “ARCA biopharma, Inc.”, such change to become effective upon the effectiveness of the Merger;

FURTHER RESOLVED, that the assumption by the Corporation of all of the Subsidiary’s liabilities and obligations of the Subsidiary be, and it hereby is, authorized, approved and adopted in all respects;

FURTHER RESOLVED, that by virtue of the Merger and without any action on the part of the holder thereof, each then outstanding share of common stock of the Subsidiary shall be canceled and no consideration shall be issued in respect thereof; and

FURTHER RESOLVED, that the President or any Vice President of the Corporation be, and is hereby, authorized to make, execute and acknowledge a Certificate of Ownership and Merger setting forth a copy of the resolution to merge said Subsidiary with and into the Corporation, to effect the name change above and to assume the Subsidiary’s liabilities and obligations and the date of adoption thereof and to file the same in the office of the Secretary of State of Delaware, and to do all acts and things whatsoever, whether within or without the State of Delaware, which may be in any way necessary or appropriate to effect said Merger.

FOURTH : Pursuant to Section 253(b) of the Delaware Law, upon the effectiveness of the Merger, the Corporation, as the surviving corporation in the Merger, will change its corporate name to “ARCA biopharma, Inc.”

[Remainder of page intentionally left blank]

IN WITNESS WHEREOF, the Corporation has caused this Certificate of Ownership and Merger to be signed by an authorized officer this 27 day of January, 2009.


NUVELO, INC.

By:		/s/ Christopher Ozeroff
Name:		Christopher Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

Exhibit 3.2

AMENDED AND RESTATED

BY-LAWS

NUVELO, INC.

A DOPTED D ECEMBER 6, 2007

ARTICLE I

OFFICES

SECTION 1. REGISTERED OFFICE. The address of the Corporation’s registered office in the State of Delaware is c/o the Corporation Trust Company, Corporation Trust Center, 1209 Orange Street, City of Wilmington, County of New Castle, 19801.

SECTION 2. OTHER OFFICES. The board of directors may at any time establish other offices at any place or places where the corporation is qualified to do business.

ARTICLE II

STOCKHOLDERS

SECTION 1. ANNUAL MEETING. An annual meeting of the stockholders entitled under the corporation’s Certificate of Incorporation (the “Certificate of Incorporation”) and these by-laws to vote on matters properly to be considered at an annual meeting shall be held each year on a date and at a time designated by the board of directors. Any previously scheduled annual meeting of the stockholders may be postponed by resolution of the board of directors upon public notice given prior to the date previously scheduled for such annual meeting of the stockholders. At the meeting, directors shall be elected and any other proper business may be transacted.

SECTION 2. SPECIAL MEETINGS. Special meetings of the stockholders may be called by the chief executive officer, president, the board of directors, or by holders of Common Stock who hold, in the aggregate, not less than fifty percent (50%) of the outstanding shares of Common Stock for the purpose or purposes stated in the call of the meeting.

SECTION 3. PLACE OF MEETINGS. Meetings of stockholders may be held at such place, within or without the State of Delaware, and at such time as shall be determined pursuant to Section 2 of this Article II, and stated in the notice of the meeting or in a duly executed waiver of notice thereof.

SECTION 4. NOTICE OF MEETINGS. A written notice of each meeting of stockholders, stating the place, date and hour of the meeting and, in the case of a special meeting, the purpose or purposes for which the meeting is called, shall be given to each stockholder entitled to vote at the meeting. Unless otherwise provided by the General Corporation Law of the State of Delaware (“Delaware Law”), the notice shall be given not less than ten (10) nor more than sixty (60) days before the date of the meeting, and, if mailed, shall be deposited in the United States mail, postage prepaid, directed to the stockholder at the stockholder’s address as it appears on the records of the corporation. An affidavit of the secretary or an assistant secretary or of the transfer agent of the corporation that the notice has been given shall, in the absence of fraud, be prima facie evidence of the facts stated therein.

SECTION 5. ADVANCE NOTICE OF BUSINESS TO BE TRANSACTED AT ANNUAL MEETING.

(a) Nominations of persons for election to the board of directors and the proposal of business to be considered by the stockholders may be made at an annual meeting of stockholders (i) pursuant to the corporation’s notice of meeting, (ii) by or at the direction of the board of directors, or (iii) by any stockholder of the corporation who was a stockholder of record at the time of giving notice provided for in Section 5(b), who is entitled to vote at the meeting and who complied with the notice procedures set forth in Section 5(b).

(b) For nominations or other business to be properly brought before an annual meeting by a stockholder pursuant to Section 5(a)(iii), the stockholder must have given timely notice thereof in writing to the secretary of the corporation. To be timely, a stockholder’s notice shall be delivered to the secretary at the principal executive offices of the corporation not less than sixty (60) days nor more than ninety (90) days prior to the first anniversary of the preceding year’s annual meeting; provided, however, that in the event that the date of the annual meeting is advanced by more than thirty (30) days or delayed by more than sixty (60) days from such anniversary date, notice by the stockholder to be timely must be so delivered not earlier than the ninetieth (90 ^th ) day prior to such annual meeting and not later than the close of business on the later of the sixtieth (60 ^th ) day prior to such annual meeting or the tenth (10 ^th ) day following the earlier of the day on which public announcement of the date of such meeting is first made or notice is first given. Such stockholder’s notice shall set forth (i) as to each person whom the stockholder proposes to nominate for election or reelection as a director, all information relating to such person that is required to be disclosed in solicitations of proxies for election of directors, or is otherwise required, in each case pursuant to Regulation 14A under the Securities and Exchange Act of 1934, as amended (the “Exchange Act”) (including such person’s written consent to being named in the proxy statement as a nominee and to serving as a director if elected), (ii) as to any other business that the stockholder proposes to bring before the meeting, a brief description of the business desired to be brought before the meeting, the reasons for conducting such business at the meeting and any material interest in such business of such stockholder and of the beneficial owner, if any, on whose behalf the proposal is made, and (iii) as to the stockholder giving the notice and the beneficial owner, if any, on whose behalf the nomination or proposal is made, (A) the name and address of such stockholder, as they appear on the corporation’s books, and of such beneficial owner and (B) the class and number of shares of the corporation which are owned beneficially and of record by such stockholders and such beneficial owner.

(c) Notwithstanding anything in the second sentence of Section 5(b) to the contrary, in the event that the number of directors to be elected to the board of directors is increased and there is no public announcement naming all of the nominees for director or specifying the size of the increased board of directors made by the corporation at least seventy (70) days prior to the first anniversary of the preceding year’s annual meeting (or, if the annual meeting is held more than thirty (30) days before or sixty (60) days after such anniversary date, at least seventy (70) days prior to such annual meeting), a stockholder’s notice required by this Section 5 shall also be considered timely, but only with respect to nominees for any new positions created by such increase, if it shall be delivered to the secretary at the principal executive offices of the corporation not later than the close of business on the tenth (10 ^th ) day following the day on which such public announcement is first made by the corporation.

(d) Except as set forth in Section 9 of Article III, only such persons who are nominated in accordance with the procedures set forth in this Section 5 shall be eligible to serve as directors and only such business shall be conducted at a meeting of stockholders as shall have been brought before the meeting in accordance with the procedures set forth in this Section 5. The presiding officer of the meeting shall have the power and duty to determine whether a nomination or any business proposed to be brought before the meeting was made in accordance with the procedures set forth in this Section 5 and, if any proposed nomination or business is not in compliance with this Section 5, to declare that such defective nomination or proposal be disregarded.

(e) For purposes of this Section 5, “public announcement” shall mean disclosure in a press release reported by the Dow Jones News Service, Associated Press or comparable new service or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Section 13, 14 or 15(d) of the Exchange Act.

(f) Notwithstanding the foregoing provisions of this Section 5, a stockholder shall also comply with all applicable requirements of state law and of the Exchange Act and the rules and regulations thereunder with respect to the matters set forth in this Section 5. Nothing in this Section 5 shall be deemed to affect any rights of stockholders to request inclusion of proposals in the corporation’s proxy statement pursuant to Rule 14a-8 under the Exchange Act.

SECTION 6. WAIVER OF NOTICE. Anything herein to the contrary notwithstanding, with respect to any stockholder meeting, any stockholder who in person or by proxy shall have waived in writing notice of the meeting, either before or after such meeting, or who shall attend the meeting in person or by proxy, shall be deemed to have waived notice of such meeting unless he or she attends for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened.

SECTION 7. QUORUM; MANNER OF ACTING AND ORDER OF BUSINESS.

(a) Subject to the provisions of these by-laws, the Certificate of Incorporation and Delaware Law as to the vote that is required for a specified action, the presence in person or by proxy of the holders of a majority of the outstanding shares of the corporation entitled to vote at any meeting of stockholders shall constitute a quorum for the transaction of business. The vote of the holders of a majority of the shares of the corporation’s stock entitled to vote on the proposal, present in person or represented by proxy, shall be binding on all stockholders of the corporation, unless the vote of a greater number or voting by classes is required by law or the Certificate of Incorporation or these by-laws. The stockholders present at a duly called or held meeting at which a quorum is present may continue to do business until adjournment, notwithstanding the withdrawal of enough stockholders to leave less than a quorum.

(b) In the absence of a quorum, stockholders holding a majority of the shares present in person or by proxy and entitled to vote, regardless of whether or not they constitute a quorum, or if no stockholders are present, any officer entitled to preside at or act as secretary of the meeting, may adjourn the meeting to another time and place. Any business which might have been transacted at the original meeting may be transacted at any adjourned meeting at which a quorum is present. No notice of an adjourned meeting need be given if the time and place are announced at the meeting at which the adjournment is taken except that, if adjournment is for more than thirty (30) days or if, after the adjournment, a new record date is fixed for the meeting, notice of the adjourned meeting shall be given pursuant to Section 4 of this Article II.

(c) Meetings of the stockholders shall be presided over by the chairman of the board or, if the chairman so elects or is absent, the vice chairman of the board, or in their absence by the chief executive officer, or in his or her absence by the president, or in his or her absence by a vice president, or in the absence of the foregoing persons by a chairman designated by the board of directors, or in the absence of such designation by a chairman chosen at the meeting. The secretary shall act as secretary of the meeting, but in his or her absence the chairman of the meeting may appoint any person to act as secretary of the meeting. The order of business at all meetings of the stockholders shall be determined by the chairman. The order of business so determined, however, may be changed by vote of the holders of a majority of the shares present at the meeting in person or represented by proxy.

SECTION 8. VOTING; PROXIES.

(a) The stockholders entitled to vote at any meeting of stockholders shall be determined in accordance with the provisions of Section 6 of Article VI. All elections of directors shall be by written ballot.

(b) Each stockholder entitled to vote at any meeting of stockholders may authorize another person to act for such stockholder by proxy. No proxy shall be valid after three years from its date of execution, unless the proxy provides for a longer period.

SECTION 9. INSPECTORS OF ELECTION.

(a) In advance of any meeting of stockholders, the board of directors may appoint inspectors of election to act at each meeting of stockholders and any adjournment thereof. If inspectors of election are not so appointed, the chairman of the meeting may, and upon the request of any stockholder or any stockholder’s proxy shall, appoint inspectors of election at the meeting. The number of inspectors shall be either one or three. If appointed at the meeting upon the request of one or more stockholders or proxies, the vote of the holders of a majority of shares present shall determine whether one or three inspectors are appointed. In any case any person appointed as an inspector fails to appear or fails or refuses to act, the vacancy may be filled by appointment made by the directors in advance of the convening of the meeting or at the meeting by the person acting as chairman.

(b) The inspectors of election shall determine the outstanding stock of the corporation, the stock represented at the meeting and the existence of a quorum, shall receive votes, ballots, or consents, shall count and tabulate all votes and shall determine the result; and in connection therewith, the inspectors shall determine the authority, validity and effect of proxies, hear and determine all challenges and questions, and do such other ministerial acts as may be proper to conduct the election or vote with fairness to all stockholders.

If there are three inspectors of election, the decision, act or certificate of a majority is effective in all respects as the decision, act or certificate of all. If no inspectors of election are appointed, the secretary shall pass upon all questions and shall have all other duties specified in this Section 9.

(c) Upon request of the chairman of the meeting or any stockholder or stockholder’s proxy, the inspector(s) of election shall make a report in writing of any challenge or question or other matter determined by the inspector(s) and shall execute a certificate of any fact found in connection therewith. Any such report or certificate shall be filed with the record of the meeting.

SECTION 10. NO ACTION WITHOUT A MEETING. No action of the stockholders may be taken by written consent.

SECTION 11. REVOCATION OF CONSENT. Any stockholder giving a written consent, or the stockholder’s proxyholders, or a transferee of the shares or a personal representative of the stockholder or its respective proxyholder, may revoke the consent by a writing received by the corporation prior to the time that written consents of the number of shares required to authorize the proposed action have been filed with the secretary of the corporation, but may not do so thereafter. Such revocation is effective upon its receipt by the secretary of the corporation.

ARTICLE III

DIRECTORS

SECTION 1. NUMBER, TENURE AND QUALIFICATIONS.

(a) The number of directors of the corporation shall consist of not less than two (2) nor more than nine (9) directors, the exact number of directors to be determined from time to time by resolution adopted by the affirmative vote of a majority of the directors. A director shall hold office until the later of (i) the next annual meeting of the stockholders of the corporation immediately following, or (ii) coinciding with the expiration of the director’s term or until the director’s successor shall be elected and shall qualify, subject, however, to prior death, resignation, retirement, disqualification or removal from office. Directors need not be residents of the State of Delaware or stockholders of the corporation.

(b) Any director or the entire board of directors may be removed, with cause, by the holders of 66 ² / 3 % of the voting rights of the shares then entitled to vote at an election of directors, unless otherwise provided under Delaware Law or the Certificate of Incorporation.

(c) No reduction of the authorized number of directors shall have the effect of removing any director before that director’s term of office expires.

(d) There shall be no right with respect to shares of stock of the corporation to cumulate votes in the election of directors.

SECTION 2. RESIGNATIONS. Any director may resign at any time by giving written notice to the chairman of the board, or to the vice chairman of the board, or to the chief executive officer, or to the president.

SECTION 3. MEETINGS. Regular meetings of the board of directors may be held without notice at such time and at such place as shall from time to time be determined by the board. Special meetings of the board of directors may be called by or at the request of the chairman of the board, the vice chairman of the board, the chief executive officer, the president or a majority of the directors. The person or persons authorized to call meetings of the board of directors may fix any place as the place for holding any meeting of the board of directors called by them. Meetings of the board of directors may be held within or outside the State of Delaware.

SECTION 4. BUSINESS OF MEETINGS. Except as otherwise expressly provided in these by-laws, any and all business may be transacted at any meeting of the board of directors.

SECTION 5. NOTICE OF MEETINGS. Notice of any meeting shall be given at least one (1) day previous thereto by prior written notice to each director at such director’s principal place of business.

SECTION 6. ATTENDANCE BY TELEPHONE. Directors may participate in meetings of the board of directors by means of conference telephone or similar communications equipment by means of which all directors participating in the meeting can hear one another, and such participation shall constitute presence in person at the meeting.

SECTION 7. QUORUM AND MANNER OF ACTING; ADJOURNMENT. A majority of the directors shall constitute a quorum for the transaction of business at any meeting of the board of directors and the act of a majority of the directors present at any meeting at which a quorum is present shall be the act of the board.

SECTION 8. ACTION WITHOUT A MEETING. Any action which could be taken at a meeting of the board of directors may be taken without a meeting if all of the directors consent to the action in writing and the writing or writings are filed with the minutes of proceedings of the board. Written consents representing actions taken by the board may be executed by telex, telecopy or other facsimile transmission, and such facsimile shall be valid and binding to the same extent as if it were an original.

SECTION 9. FILLING OF VACANCIES.

(a) A vacancy or vacancies in the board of directors shall exist when any previously authorized position of director is not then filled by a duly elected director, whether caused by death, resignation or removal. Vacancies caused by reason of death, resignation or removal shall be filled by a majority of the directors then in office, although less than a quorum, or by a sole remaining director.

(b) Vacancies and newly created directorships resulting from an increase in the authorized number of directors elected by all the stockholders having the right to vote as a single class may be filled by a majority of the directors then in office, although less than a quorum, or by a sole remaining director.

(c) If at any time, by reason of death or resignation or other cause, the corporation should have no directors in office, then any officer or any stockholder or an executor, administrator, trustee or guardian of a stockholder, or other fiduciary entrusted with like responsibility for the person or estate of a stockholder, may call a special meeting of stockholders in accordance with the Certificate of Incorporation or the by-laws, or may apply to a court of appropriate jurisdiction for a decree summarily ordering an election.

SECTION 10. COMPENSATION OF DIRECTORS. The board of directors shall have the authority to fix the compensation of directors, unless otherwise provided in the Certificate of Incorporation.

SECTION 11. PRESIDING DIRECTOR. The presiding director at any meeting of the board of directors shall be the chairman of the board or the vice chairman of the board, or in their absence, any other director elected chairman by vote of a majority of the directors present at the meeting.

SECTION 12. COMMITTEES. The board of directors, by resolution adopted by a majority of the number of directors fixed by the by-laws or otherwise, may designate one (1) or more committees, each committee to consist of one (1) or more directors of the corporation, which committees, to the extent provided in such resolution, shall have and exercise all of the authority of the board of directors in the management of the corporation, except as otherwise required by law. The board of directors may designate one (1) or more directors as alternate members of any committee, who may replace any absent or disqualified member at any meeting of the committee.

SECTION 13. WAIVER OF NOTICE. Anything herein to the contrary notwithstanding, with respect to any meeting of the board of directors, any director who in person shall have waived in writing notice of the meeting, either before or after such meeting, or who shall attend the meeting in person, shall be deemed to have waived notice of such meeting unless he or she attends for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened.

ARTICLE IV

OFFICERS

SECTION 1. NUMBER. The officers of the corporation may consist of the chairman of the board, the vice chairman of the board, the chief executive officer, the president, one or more vice presidents (the number thereof to be determined by the board of directors), the secretary, the treasurer, the registered agent, and such assistant secretaries and assistant treasurers or any other officers thereunto authorized or elected by the board of directors. Any two or more offices may be held by the same person.

SECTION 2. ELECTION AND TERM OF OFFICE. The officers of the corporation shall be elected by the board of directors at their first meeting and thereafter at any subsequent meeting and shall hold their offices for such term as determined by the board of directors. Each officer shall hold office until such officer’s successor is duly elected and qualified, or until such officer’s death or disability, or until such officer resigns or is removed from his or her duties in the manner hereinafter provided.

SECTION 3. REMOVAL AND RESIGNATION. Any officer may be removed, either with or without cause, by a majority of the directors, then in office, at any meeting of the board of directors. Any officer may resign at any time by giving written notice to the corporation. Any such resignation shall take effect at the date of the receipt of such notice or at any later time specified therein.

SECTION 4. VACANCIES. A vacancy in any office because of death, resignation or removal or any other cause may be filled for the unexpired portion of the term by the board of directors.

SECTION 5. CHAIRMAN OF THE BOARD. Except to the extent required by Delaware Law, the chairman of the board of the corporation shall not be deemed an officer of the corporation, unless expressly so designated by the board of directors. The chairman of the board or, if the chairman so elects, the vice chairman of the board shall preside at all meetings of the board of directors, and at all stockholders’ meetings, whether annual or special, at which he or she is present and shall exercise such other powers and perform such other duties as the board of directors may from time to time assign to him or her or as may be prescribed by these by-laws. In the event that the chairman of the board is not present at a stockholders’ meeting, the vice chairman of the board, or in his or her absence the chief executive officer, or in his or her absence the president of the corporation, shall serve in his or her place and stead. Except in those instances in which the authority to execute is expressly delegated to another officer or agent of the corporation, or a different mode of execution is expressly prescribed by the board of directors or these by-laws, he or she may execute for the corporation certificates for its shares, and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, and he or she may accomplish such execution either under or without the seal of the corporation, or either individually with the secretary, any assistant secretary or any other officer thereunto authorized by the board of directors, according to the requirements of the form of the instrument.

SECTION 6. VICE CHAIRMAN OF THE BOARD. Except to the extent required by Delaware Law, the vice chairman of the board of the corporation shall not be deemed an officer of the corporation, unless expressly so designated by the board of directors. The vice chairman of the board, if one shall be elected, shall assist the chairman of the board in the discharge of his or her duties, as the chairman may direct and shall perform such other duties as from time to time may be assigned to him or her by the chairman or by the board of directors. In the absence of the chairman or in the event of his or her inability or refusal to act, the vice chairman shall perform the duties of the chairman, and when so acting, shall have the powers of and be subject to all the restrictions upon the chairman. Except in those instances in which the authority to execute is expressly delegated to another officer or agent of the corporation, or a different mode of execution is expressly prescribed by the board of directors or these by-laws, he or she may execute for the corporation certificates for its shares, and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, and he or she may

accomplish such execution either under or without the seal of the corporation, or either individually with the secretary, any assistant secretary or any other officer thereunto authorized by the board of directors, according to the requirements of the form of the instrument.

SECTION 7. CHIEF EXECUTIVE OFFICER. Subject to the direction and control of the board of directors, the chief executive officer shall be in charge of the general management and supervision over the property, affairs and business of the corporation. Except in those instances in which the authority to execute is expressly delegated to another officer or agent of the corporation, or a different mode of execution is expressly prescribed by the board of directors or these by-laws, he or she may execute for the corporation, certificates for its shares, and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, and he or she may accomplish such execution either under or without the seal of the corporation, or either individually or with the secretary, any assistant secretary or any other officer thereunto authorized by the board of directors, according to the requirements of the form of the instrument. He or she may vote all securities which the corporation is entitled to vote, except as and to the extent such authority shall be vested in a different officer or agent of the corporation by the board of directors.

SECTION 8. PRESIDENT. Subject to the direction and control of the board of directors and the chief executive officer, the president shall be in charge of the general management and supervision over the operating functions of the corporation; he or she shall see that the resolutions and directions of the board of directors are carried into effect, except in those instances in which that responsibility is specifically assigned to some other person by the board of directors; and in general, he or she shall discharge all duties incident to the office of president and such other duties as may be prescribed by the board of directors from time to time. Except in those instances in which the authority to execute is expressly delegated to another officer or agent of the corporation, or a different mode of execution is expressly prescribed by the board of directors or these by-laws, he or she may execute for the corporation, certificates for its shares, and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, and he or she may accomplish such execution either under or without the seal of the corporation, or either individually or with the secretary, any assistant secretary or any other officer thereunto authorized by the board of directors, according to the requirements of the form of the instrument.

SECTION 9. VICE PRESIDENT. The vice president (or in the event there be more than one vice president, each of the vice presidents), if one shall be elected, shall assist the president in the discharge of his or her duties, as the president may direct and shall perform such other duties as from time to time may be assigned to him or her by the president or by the board of directors. In the absence of the president or in the event of his or her inability or refusal to act, the vice president (or in the event there be more than one vice president, the vice presidents in the order designated by the board of directors, or by the president if the board of directors have not made such a designation, or in the absence of any designation, then in the order of seniority of tenure as vice president) shall perform the duties of the president, and when so acting, shall have the powers of and be subject to all the restrictions upon the president.

Except in those instances in which the authority to execute is expressly delegated to another officer or agent of the corporation, or a different mode of execution is expressly prescribed by the board of directors or these by-laws, the vice president (or each of them if there are more than one) may execute for the corporation, certificates for its shares and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, and he or she may accomplish such execution either under or without the seal of the corporation, and either individually or with the secretary, any assistant secretary or any other officer thereunto authorized by the board of directors, according to the requirements of the form of the instrument.

SECTION 10. TREASURER. The treasurer, if any, shall be the principal accounting and financial officer of the corporation. The treasurer shall: (i) have charge of and be responsible for the maintenance of the adequate books and records for the corporation; (ii) have charge and custody of all funds and securities of the corporation, and be responsible therefor and for the receipt and disbursement thereof; and (iii) perform all the duties incident to the office of treasurer and such other duties as from time to time may be assigned to him or her by the president or by the board of directors. If required by the board of directors, the treasurer shall give a bond for the faithful discharge of his or her duties in such sum and with such surety or sureties as the board of directors may determine.

SECTION 11. SECRETARY. The secretary shall: (i) record the minutes of the stockholders and of the board of directors’ meetings in one or more books provided for that purpose; (ii) see that all notices are duly given in accordance with the provisions of these by-laws or as required by law; (iii) be custodian of the corporate books and records and of the seal of the corporation; (iv) keep a register of the post-office address of each stockholder which shall be furnished to the secretary by such stockholder; (v) sign with the chairman of the board or the vice chairman of the board or the chief executive officer or the president or a vice president or any other officer thereunto authorized by the board of directors, certificates for the shares of the corporation, if such shares are represented by certificates, the issue of which shall have been authorized by the board of directors, and any contracts, deeds, mortgages, bonds or other instruments which the board of directors have authorized to be executed, according to the requirements of the form of the instrument, except when a different mode of execution is expressly prescribed by the board of directors or these by-laws; (vi) have general charge of the stock transfer books of the corporation; (vii) perform all duties incident to the office of secretary and such other duties as from time to time may be assigned to him or her by the president or by the board of directors. The secretary will also supply to the registered agent, and maintain, a current statement setting out the name of the custodian of the stock ledger or duplicate stock ledger, and the present and complete post office address, including street and number, if any, where such stock ledger or duplicate stock ledger specified in the section is kept.

SECTION 12. REGISTERED AGENT. The registered agent shall be in charge of the corporation’s registered office in the State of Delaware, upon whom process against the corporation may be served and shall perform all duties required by statute.

SECTION 13. ASSISTANT TREASURERS AND ASSISTANT SECRETARIES. The assistant treasurers and assistant secretaries shall perform such duties as shall be assigned to them by the board of directors. When the secretary is unavailable, any assistant secretary may sign with the chief executive officer, the president, or a vice president, or any other officer thereunto authorized by the board of directors, any contracts, deeds, mortgages, bonds or other instruments according to the requirements of the form of the instrument, except when a different mode of execution is expressly prescribed by the board of directors or these by-laws. The assistant treasurers shall, respectively, if required by the board of directors, give bonds for the faithful discharge of their duties in such sums and with such sureties as the board of directors shall determine.

SECTION 14. SALARIES. The salaries of the officers shall be fixed from time to time by the board of directors and no officer shall be prevented from receiving such salary by reason of the fact that he or she is also a director of the corporation.

ARTICLE V

CONTRACTS, LOANS, CHECKS AND DEPOSITS

SECTION 1. CONTRACTS. The board of directors may authorize any officer or officers, agent or agents, to enter into any contract or execute and deliver any instrument in the name of and on behalf of the corporation and such authority may be general or confined to specific instances.

SECTION 2. LOANS. No loans shall be contracted on behalf of the corporation and no evidences of indebtedness shall be issued in its name, unless authorized by a resolution of the board of directors. Such authority may be general or confined to specific instances.

SECTION 3. CHECKS, DRAFTS, ETC. All checks, drafts or other orders for the payment of money, notes or other evidences of indebtedness issued by the name of the corporation, shall be signed by such officer or officers, agent or agents of the corporation and in such manner as shall from time to time be determined by resolution of the board of directors.

SECTION 4. DEPOSITS. All funds of the corporation not otherwise employed shall be deposited from time to time to the credit of the corporation in such banks, trust companies or other depositaries as the board of directors may select.

ARTICLE VI

CERTIFICATES OF STOCK AND THEIR TRANSFER

SECTION 1. STOCK RECORD AND CERTIFICATES. Records shall be kept by or on behalf of the corporation, which shall contain the names and addresses of stockholders, the number of shares held by them respectively, and the number of certificates, if any, representing the shares, and in which there shall be recorded all transfers of shares. The shares of the corporation shall be represented by certificate, or, upon resolution adopted by the board of directors, shall be uncertificated shares. Any such resolution shall not apply to shares represented by a certificate until such certificate is surrendered to the corporation. Every holder of shares represented by certificate in the corporation shall be entitled to a certificate signed by the chairman of the board of directors, or the vice chairman of the board, or the chief executive officer or the president or a vice president, and by the treasurer or an assistant treasurer, or the secretary or an assistant secretary of the corporation, certifying the class and number of shares owned by such holder in the corporation, provided that any and all signatures on a certificate may be a facsimile. In case any officer, transfer agent or registrar who has signed or whose facsimile signature has been placed upon a certificate shall have ceased to be such officer, transfer agent or registrar before such certificate is issued, it may be issued by the corporation with the same effect as if he, she or it were such officer, transfer agent or registrar at the date of issue. Holders of uncertificated shares shall not be entitled to a certificate representing such shares.

SECTION 2. TRANSFER AGENTS AND REGISTRARS. The board of directors may, in its discretion, appoint one or more responsible banks or trust companies as the board may deem advisable, from time to time, to act as transfer agents and registrars of shares of the corporation; and, when such appointments shall have been made, no certificate for shares of the corporation shall be valid until countersigned by one of such transfer agents and registered by one of such registrars.

SECTION 3. STOCKHOLDERS’ ADDRESSES. Every stockholder or transferee shall furnish the secretary or a transfer agent with the address to which notice of meetings and all other notices may be served upon or mailed to such stockholder or transferee, and in default thereof, such stockholder or transferee shall not be entitled to service or mailing of any such notice.

SECTION 4. LOST CERTIFICATES. In case any certificate for shares of the corporation is lost, stolen or destroyed, the board of directors, in its discretion, or any transfer agent duly authorized by the board, may authorize the issue of a substitute certificate in place of the certificate so lost, stolen or destroyed. The corporation may require the owner of the lost, stolen or destroyed certificate or the owner’s legal representative to give the corporation a bond sufficient to indemnify the corporation against any claim that may be made against it on account of the alleged loss, theft or destruction of any such certificate or the issuance of such new certificate or uncertified shares.

SECTION 5. DISTRIBUTIONS TO STOCKHOLDERS. To the extent permitted by Delaware Law and subject to any restrictions contained in the Certificate of Incorporation, the directors may declare and pay dividends upon the shares of its capital stock in the manner and upon the terms and conditions provided by Delaware Law and the Certificate of Incorporation.

SECTION 6. RECORD DATES. In order that the corporation may determine the stockholders entitled to notice of or to vote at any meeting of stockholders, or any adjournment thereof, or entitled to receive payment of any dividend or other distribution or allotment of any rights, or entitled to exercise any rights in respect of any change, conversion or exchange of shares or for the purpose of any other lawful action, the board of directors may fix, in advance, a record date which shall be not more than sixty (60) nor less than ten (10) days before the date of any meeting of stockholders, and not more than sixty (60) days prior to any other action. In such case, those stockholders, and only those stockholders, who are stockholders of record on the date fixed by the board of directors shall, notwithstanding any subsequent transfer of shares on the books of the corporation, be entitled to notice of and to vote at such meeting of stockholders, or any adjournment thereof, or be entitled to receive payment of such dividend or other distribution or allotment of rights, or entitled to exercise rights in respect of any such change, conversion or exchange of shares or to participate in any such other lawful action.

A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the board of directors may fix a new record date for the adjourned meeting.

SECTION 7. TRANSFERS OF SHARES. Shares of the corporation may be transferred by delivery of the certificates therefor, accompanied either by an assignment in writing on the back of the certificates, or by written power of attorney to sell, assign and transfer the same, signed by the record holder thereof, or, if such shares are uncertificated, by assignment in writing, or by written power of attorney to sell, assign and transfer the same, signed by the record holder thereof; but no transfer shall affect the right of the corporation to pay any distribution upon the shares to the holder of record thereof, or to treat the holder of record as the holder in fact thereof for all purposes, and no transfer shall be valid, except between the parties thereto, until such transfer shall have been made upon the books of the corporation.

SECTION 8. REPURCHASE OF SHARES ON OPEN MARKET. The corporation may purchase its shares on the open market and invest its assets in its own shares, provided that in each case the consent of the board of directors shall have been obtained.

ARTICLE VII

INDEMNIFICATION AND INSURANCE

SECTION 1. DEFINITIONS. For the purposes of this Article VII the following definitions shall apply:

“Agent” means any person who: (i) is or was a director, officer, employee, or other agent of this corporation; or (ii) is or was serving at the request of this corporation as a director, officer, employee, or agent of another foreign or domestic corporation, partnership, joint venture, trust or other enterprise (“enterprise”).

“Proceeding” means any threatened, pending or completed action suit or proceeding, whether civil, criminal, administrative, or investigative and whether internal or external to the corporation.

“Expenses” includes, without limitation, attorneys’ fees and any expenses of establishing a right to indemnification under this Article VII.

“Losses” mean the total amount which the agent becomes legally obligated to pay in connection with any proceeding, including judgments, fines, amounts paid in settlement and Expenses.

SECTION 2. THIRD PARTY ACTIONS. The corporation shall indemnify any person who was or is a party or is threatened to be made a party to, or otherwise becomes involved in, any Proceeding (other than an action by or in the right of the corporation) by reason of the fact that the person is or was an Agent of the corporation against Losses actually and reasonably incurred by the person in connection with such Proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal Proceeding, had no reasonable cause to believe the person’s conduct was unlawful. The termination of any Proceeding by judgment, order, settlement, conviction, or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that the person did not act in good faith and in such a manner which the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal Proceeding, had reasonable cause to believe that the person’s conduct was unlawful.

SECTION 3. ACTIONS BY OR IN THE RIGHT OF THE CORPORATION. The corporation shall indemnify any person who was or is a party or is threatened to be made a party to, or otherwise becomes involved in, any Proceeding by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was an Agent of the corporation against Expenses actually and reasonably incurred by the person in connection with the defense or settlement of such Proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged by a court of competent jurisdiction to be liable to the corporation unless and only to the extent that the court in which such Proceeding was brought shall determine upon application that, in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such Expenses as the court shall deem proper.

SECTION 4. SUCCESSFUL DEFENSE. To the extent that an Agent of the corporation has been successful on the merits or otherwise in defense of any Proceeding referred to in Sections 2 and 3 of this Article VII, or in defense of any claim, issue or matter therein, he or she must be indemnified against Expenses actually and reasonably incurred by him or her in connection therewith.

SECTION 5. DETERMINATION OF CONDUCT. Any indemnification under Sections 2 and 3 of this Article VII, (unless ordered by a court or advanced pursuant to Section 6 of this Article VII) shall be made by the corporation only as authorized in the specific case upon a determination that indemnification of the Agent is proper in the circumstances because he or she has met the applicable standard of conduct set forth in Sections 2 and 3 of this Article VII. Such determination shall be made (a) by the board of directors by a majority vote of a quorum consisting of directors who were not parties to such Proceeding, or (b) if such a quorum is not obtainable or, even if obtainable, a quorum of disinterested directors so directs, by independent legal counsel in a written opinion, or (c) if a majority vote of a quorum consisting of directors who were not parties to the Proceeding so orders, by independent legal counsel in a written opinion, or (d) by the stockholders.

SECTION 6. PAYMENT OF EXPENSES IN ADVANCE. Expenses incurred by an Agent in connection with a Proceeding shall be paid by the corporation as they are incurred and in advance of the final disposition of such Proceeding upon receipt of an undertaking by or on behalf of such Agent to repay such amount if it shall ultimately be determined by a court of competent jurisdiction that he or she is not entitled to be indemnified by the corporation as authorized in this Article VII.

SECTION 7. INDEMNITY NOT EXCLUSIVE. The indemnification and advancement of Expenses provided by, or granted pursuant to, the other provisions of this Article VII shall not be deemed exclusive of any other rights to which a person seeking indemnification or advancement of Expenses may be entitled under any by-law, agreement, vote of stockholders or disinterested directors, or otherwise, both as to action in his or her official capacity and as to action in another capacity while holding such office.

SECTION 8. INSURANCE INDEMNIFICATION. The corporation shall have the power to purchase and maintain insurance on behalf of any person who is or was an Agent of the corporation against any liability asserted against the person and incurred by the person in any such capacity, or arising out of the person’s status as such, whether or not the corporation would have the power to indemnify the person against such liability under the provisions of this Article VII.

SECTION 9. HEIRS, EXECUTORS AND ADMINISTRATORS. The indemnification and advancement of Expenses provided by, or granted pursuant to, this Article VII shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be an Agent and shall inure to the benefit of the heirs, executors and administrators of such a person.

SECTION 10. FURTHER AMENDMENT. Notwithstanding any provision in this Article VII to the contrary, in the event the Delaware Law is either amended to provide, or interpreted by judicial or other binding legal decision to provide, broader indemnification rights than those contained herein, such broader indemnification rights shall be provided to any and all persons entitled to be indemnified pursuant to the Delaware Law the intent of this provision being to permit the corporation to indemnify, to the full extent permitted by Delaware Law, persons whom it may indemnify thereunder.

ARTICLE VIII

AMENDMENTS

The by-laws may be amended, altered or repealed by a majority vote of the directors or by an affirmative vote by the holders of 66- ² / 3 % of the voting rights of all classes of stock entitled to vote. The by-laws may contain any provisions for the regulation and management of the affairs of the corporation not inconsistent with Delaware Law or the Certificate of Incorporation.

* * *

CERTIFICATE OF SECRETARY

I, the undersigned, do hereby certify:

(1) That I am the duly elected and acting Secretary of Nuvelo, Inc., a Delaware corporation; and

(2) That the foregoing Amended and Restated By-laws constitute the by-laws of said corporation as amended and restated by the Board of Directors on December 6, 2007.

IN WITNESS WHEREOF, I have hereunto subscribed my name this 12 ^th day of December, 2007.

/s/ Lee Bendekgey

Lee Bendekgey, Secretary

AMENDMENT TO AMENDED AND RESTATED BYLAWS

NUVELO, INC.,

a Delaware corporation

Effective January 23, 2009 by resolutions duly adopted by a majority of the Board of Directors of Nuvelo, Inc. (the “ Company ”) on January 23, 2009, Article III, Section 1, Subsection (a) of the Company’s Bylaws was amended to read in its entirety as follows:

“(a) The number of directors of the corporation shall consist of not less than two (2) nor more than ten (10) directors, the exact number of directors to be determined from time to time by resolution adopted by the affirmative vote of a majority of the directors. A director shall hold office until the later of (i) the next annual meeting of the stockholders of the corporation immediately following, or (ii) coinciding with the expiration of the director’s term or until the director’s successor shall be elected and shall qualify, subject, however, to prior death, resignation, retirement, disqualification or removal from office. Directors need not be residents of the State of Delaware or stockholders of the corporation.”

The remainder of the Company’s Bylaws remain in full force and effect.

Executed at San Carlos, California, on January 23, 2009.

/s/ Lee Bendekgey

Lee Bendekgey, Secretary

Exhibit 4.3

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), OR THE SECURITIES LAWS OF ANY STATE AND, EXCEPT AND PURSUANT TO THE PROVISIONS OF ARTICLE 5 BELOW, MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER SAID ACT AND APPLICABLE STATE SECURITIES LAW OR, IN THE OPINION OF LEGAL COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER OF THESE SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE OR HYPOTHECATION IS EXEMPT FROM REGISTRATION.

WARRANT TO PURCHASE STOCK


Company:		ARCA Discovery, Inc., a Delaware corporation
Number of Shares		31,790
Class of Stock:		Series B Preferred
Warrant Price:		$2.43975 per share
Issue Date:		July 17, 2007
Expiration Date:		The 10th anniversary after the Issue Date
Credit Facility:		This Warrant is issued in connection with the Growth Capital facilities referenced in the Loan and Security Agreement between Company and Silicon Valley Bank dated July 17, 2007.

THIS WARRANT CERTIFIES THAT, for good and valuable consideration, SILICON VALLEY BANK (Silicon Valley Bank, together with any registered holder from time to time of this Warrant or any holder of the shares issuable or issued upon exercise of this Warrant as permitted by Article 5.4 herein, “Holder”) is entitled to purchase the number of fully paid and nonassessable shares of the class of securities (the “Shares”) of the Company at the Warrant Price, all as set forth above and as adjusted pursuant to Article 2 of this Warrant, subject to the provisions and upon the terms and conditions set forth in this Warrant.

ARTICLE I. EXERCISE .

1.1 Method of Exercise . Holder may exercise this Warrant at any time prior to the Expiration Date (and subject to early termination pursuant to Article 1.6) by delivering a duly executed Notice of Exercise in substantially the form attached as Appendix 1 to the principal office of the Company. Unless Holder is exercising the conversion right set forth in Article 1.2, Holder shall also deliver to the Company a check, wire transfer (to an account designated by the Company), or other form of payment acceptable to the Company for the aggregate Warrant Price for the Shares being purchased.

1.2 Conversion Right . In lieu of exercising this Warrant as specified in Article 1.1, Holder may from time to time at any time prior to the Expiration Date (and subject to early termination pursuant to Article 1.6) convert this Warrant, in whole or in part, into a number of Shares determined by dividing (a) the aggregate fair market value of the Shares or other securities otherwise issuable upon exercise of this Warrant minus the aggregate Warrant Price of such Shares by (b) the fair market value of one Share. The fair market value of the Shares shall be determined pursuant to Article 1.3.

1.3 Fair Market Value . If the Company’s common stock is traded in a public market and the Shares are common stock, the fair market value of each Share shall be the closing price of a Share reported for the business day immediately before Holder delivers its Notice of Exercise to the Company (or in the instance where the Warrant is exercised immediately prior to the effectiveness of the Company’s initial public offering, the “price to public” per share price specified in the final prospectus relating to such offering). If the Company’s common stock is traded in a public market and the Shares are preferred stock, the fair market value of a Share shall be the closing price of a share of the Company’s common stock reported for the business day immediately before Holder delivers its Notice of Exercise to the Company (or, in the instance where the Warrant is exercised immediately prior to the effectiveness of the Company’s initial public offering, the initial “price to public” per share price specified in the final prospectus relating to such offering), in both cases, multiplied by the number of shares of the Company’s common stock into which a Share is convertible. If the Company’s common stock is not traded in a public market, the Board of Directors of the Company shall determine fair market value in its reasonable good faith judgment.

1.4 Delivery of Certificate and New Warrant . Promptly after Holder exercises or converts this Warrant and, if applicable, the Company receives payment of the aggregate Warrant Price, the Company shall deliver to Holder certificates for the Shares acquired and, if this Warrant has not been fully exercised or converted and has not expired, a new Warrant representing the Shares not so acquired.

1.5 Replacement of Warrants . On receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, on delivery of an indemnity agreement reasonably satisfactory in form and amount to the Company or, in the case of mutilation on surrender and cancellation of this Warrant, the Company shall execute and deliver, in lieu of this Warrant, a new warrant of like tenor.

1.6 Treatment of Warrant Upon Acquisition of Company .

1.6.1 “ Acquisition .” For the purpose of this Warrant, “Acquisition” means any sale, exclusive license, or other disposition of all or substantially all of the assets of the Company, or any reorganization, consolidation, or merger of the Company where the holders of the Company’s securities before the transaction beneficially own less than 50% of the outstanding voting securities of the surviving entity after the transaction.

1.6.2 Treatment of Warrant at Acquisition .

(a) Upon the written request of the Company, Holder. agrees that, in the event of an Acquisition that is not an asset sale and in which the sole consideration is cash, either (i) Holder shall exercise its conversion or purchase right under this Warrant and such exercise will be deemed effective immediately prior to the consummation of such Acquisition or (ii) if Holder elects not to exercise the Warrant, this Warrant will expire upon the consummation of such Acquisition. The Company shall provide Holder with written notice of its request relating to the foregoing (together with such reasonable information as Holder may request in connection with such contemplated Acquisition giving rise to such notice), which is to be delivered to Holder not less than ten (10) days prior to the closing of the proposed Acquisition.

(b) Upon the written request of the Company, Holder agrees that, in the event of an Acquisition that is an “arms length” sale of all or substantially all of the Company’s assets (and only its assets) to a third party that is not an Affiliate (as defined below) of the Company (a “True Asset Sale”), either (i) Holder shall exercise its conversion or purchase right under this Warrant and such exercise will be deemed effective immediately prior to the consummation of such Acquisition or (ii) if Holder elects not to exercise the Warrant, this Warrant will continue until the Expiration Date if the Company continues as a going concern following the closing of any such True Asset Sale. The Company shall provide Holder with written notice of its request relating to the foregoing (together with such reasonable information as Holder may request in connection with such contemplated Acquisition giving rise to such notice), which is to be delivered to Holder not less than ten (10) days prior to the closing of the proposed Acquisition.

(c) Holder agrees that in the event of an Acquisition of the Company in which the consideration consists of capital stock of a publicly traded acquirer (or a combination of cash and capital stock of a publicly traded acquirer), if, on the record date for the Acquisition, the fair market value of the Shares (or other securities issuable upon exercise of this Warrant) is equal to or greater than two (2) times the Warrant Price, the Company may require the Warrant to be deemed automatically exercised and Holder shall participate in the Acquisition as a holder of the Shares (or other securities issuable upon exercise of this Warrant) on the same terms as the other holders of the same class of securities of the Company.

(d) Upon the closing of any Acquisition other than those particularly described in subsections (a), (b) and (c) above, the successor entity shall assume the obligations of this Warrant, and this Warrant shall be exercisable for the same securities, cash, and property as would be payable for the Shares issuable upon exercise of the unexercised portion of this Warrant as if such Shares were outstanding on the record date for the Acquisition and subsequent closing. The Warrant Price and/or number of Shares shall be adjusted accordingly.

As used herein “ Affiliate ” shall mean any person or entity that owns or controls directly or indirectly ten (10) percent or more of the stock of Company, any person or entity that controls or is controlled by or is under common control with such persons or entities, and each of such person’s or entity’s officers, directors, joint venturers or partners, as applicable.

ARTICLE II. ADJUSTMENTS TO THE SHARES .

2.1 Stock Dividends, Splits, Etc . If the Company declares or pays a dividend on the Shares payable in common stock, or other securities, then upon exercise of this Warrant, for each Share acquired, Holder shall receive, without cost to Holder, the total number and kind of securities to which Holder would have been entitled had Holder owned the Shares of record as of the date the dividend occurred. If the Company subdivides the Shares by reclassification or otherwise into a greater number of shares or takes any other action which increase the amount of stock into which the Shares are convertible, the number of shares purchasable hereunder shall be proportionately increased and the Warrant Price shall be proportionately decreased. If the

outstanding shares are combined or consolidated, by reclassification or otherwise, into a lesser number of shares, the Warrant Price shall be proportionately increased and the number of Shares shall be proportionately decreased.

2.2 Reclassification, Exchange, Combinations or Substitution . Upon any reclassification, exchange, substitution, or other event that results in a change of the number and/or class of the securities issuable upon exercise or conversion of this Warrant, Holder shall be entitled to receive, upon exercise or conversion of this Warrant, the number and kind of securities and property that Holder would have received for the Shares if this Warrant had been exercised immediately before such reclassification, exchange, substitution, or other event. Such an event shall include any automatic conversion of the outstanding or issuable securities of the Company of the same class or series as the Shares to common stock pursuant to the terms of the Company’s Certificate of Incorporation upon the closing of a registered public offering of the Company’s common stock. The Company or its successor shall promptly issue to Holder an amendment to this Warrant setting forth the number and kind of such new securities or other property issuable upon exercise or conversion of this Warrant as a result of such reclassification, exchange, substitution or other event that results in a change of the number and/or class of securities issuable upon exercise or conversion of this Warrant. The amendment to this Warrant shall provide for adjustments which shall be as nearly equivalent as may be practicable to the adjustments provided for in this Article 2 including, without limitation, adjustments to the Warrant Price and to the number of securities or property issuable upon exercise of the new Warrant. The provisions of this Article 2.2 shall similarly apply to successive reclassifications, exchanges, substitutions, or other events.

2.3 Adjustments for Diluting Issuances . The Warrant Price and the number of Shares issuable upon exercise of this Warrant or, if the Shares are preferred stock, the number of shares of common stock issuable upon conversion of the Shares, shall be subject to adjustment, from time to time in the manner set forth in the Company’s Certificate of Incorporation as if the Shares were issued and outstanding on and as of the date of any such required adjustment. The provisions set forth for the Shares in the Company’s Certificate of Incorporation relating to the above in effect as of the Issue Date may not be amended, modified or waived, without the prior written consent of Holder unless such amendment, modification or waiver affects the rights associated with the Shares in the same manner as such amendment, modification or waiver affects the rights associated with all other shares of the same series and class as the Shares granted to Holder.

2.4 No Impairment . Except and to the extent waived by Holder, the Company shall not, by amendment of its Certificate of Incorporation or through a reorganization, transfer of assets, consolidation, merger, dissolution, issue, or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms to be observed or performed under this Warrant by the Company, but shall at all times in good faith assist in carrying out of all the provisions of this Article 2 and in taking all such action as may be necessary or appropriate to protect Holder’s rights under this Article against impairment.

2.5 Fractional Shares . No fractional Shares shall be issuable upon exercise or conversion of this Warrant and the number of Shares to be issued shall be rounded down to the nearest whole Share. If a fractional share interest arises upon any exercise or conversion of the Warrant, the Company shall eliminate such fractional share interest by paying Holder the amount computed by multiplying the fractional interest by the fair market value of a full Share.

2.6 Certificate as to Adjustments . Upon each adjustment of the Warrant Price, the Company shall promptly notify Holder in writing, and, at the Company’s expense, promptly compute such adjustment, and furnish Holder with a certificate of its Chief Financial Officer setting forth such adjustment and the facts upon which such adjustment is based. The Company shall, upon written request, furnish Holder a certificate setting forth the Warrant Price in effect upon the date thereof and the series of adjustments leading to such Warrant Price.

ARTICLE III. REPRESENTATIONS AND COVENANTS OF THE COMPANY .

3.1 Representations and Warranties . The Company represents and warrants to Holder as follows:

(a) The initial Warrant Price referenced on the first page of this Warrant is not greater than (i) the price per share at which the Shares were last issued in an arms-length transaction in which at least $500,000 of the Shares were sold and (ii) the fair market value of the Shares as of the date of this Warrant.

(b) All Shares which may be issued upon the exercise of the purchase right represented by this Warrant, and all securities, if any, issuable upon conversion of the Shares, shall, upon issuance, be duly authorized, validly issued, fully paid and nonassessable, and free of any liens and encumbrances except for restrictions on transfer provided for herein or under applicable federal and state securities laws.

3.2 Notice of Certain Events . If the Company proposes at any time (a) to declare any dividend or distribution upon any of its stock, whether in cash, property, stock, or other securities and whether or not a regular cash dividend; (b) to offer for sale any shares of the Company’s capital stock (or other securities convertible into such capital stock), other than (i) pursuant to convertible debt instruments, (ii) pursuant to the Company’s stock option or other compensatory plans, (iii) in connection with commercial credit arrangements or equipment financings, or (iv) in connection with strategic transactions for purposes other than capital raising; (c) to effect any reclassification or recapitalization of any of its stock; (d) to merge or consolidate with or into any other corporation, or sell, lease, license, or convey all or substantially all of its assets, or to liquidate, dissolve or wind up; or (e) offer holders of registration rights the opportunity to participate in an underwritten public offering of the Company’s securities for cash, then, in connection with each such event, the Company shall give Holder: (1) at least 10 days prior written notice of the date on which a record will be taken for such dividend, distribution, or subscription rights (and specifying the date on which the holders of common stock will be entitled thereto) or for determining rights to vote, if any, in respect of the matters referred to in (a) and (b) above; (2) in the case of the matters referred to in (c) and (d) above at least 10 days prior written notice of the date when the same will take place (and specifying the date on which the holders of common stock will be entitled to exchange their common stock for securities or other

property deliverable upon the occurrence of such event); and (3) in the case of the matter referred to in (e) above, the same notice as is given to the holders of such registration rights. Company will also provide information reasonably requested by Holder reasonably necessary to enable Holder to comply with Holder’s accounting or reporting requirements.

3.3 Registration Under Securities Act of 1933, as amended . The Company shall add the Holder as a party to that certain Amended and Restated Investor Rights Agreement, dated as of May 31, 2007, as amended from time to time, for purposes of Sections 1, 2.1, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 2.10, 2.11, 2.12, 2.13 and 5 thereof.

3.4 No Shareholder Rights . Except as provided in this Warrant, Holder will not have any rights as a shareholder of the Company until the exercise of this Warrant.

ARTICLE IV. REPRESENTATIONS, WARRANTIES OF HOLDER . Holder represents and warrants to the Company as follows:

4.1 Purchase for Own Account . This Warrant and the securities to be acquired upon exercise of this Warrant by Holder will be acquired for investment for Holder’s account, not as a nominee or agent, and not with a view to the public resale or distribution within the meaning of the Act. Holder also represents that Holder has not been formed for the specific purpose of acquiring this Warrant or the Shares.

4.2 Disclosure of Information . Holder has received or has had full access to all the information it considers necessary or appropriate to make an informed investment decision with respect to the acquisition of this Warrant and its underlying securities. Holder further has had an opportunity to ask questions and receive answers from the Company regarding the terms and conditions of the offering of this Warrant and its underlying securities and to obtain additional information (to the extent the Company possessed such information or could acquire it without unreasonable effort or expense) necessary to verify any information furnished to Holder or to which Holder has access.

4.3 Investment Experience . Holder understands that the purchase of this Warrant and its underlying securities involves substantial risk. Holder has experience as an investor in securities of companies in the development stage and acknowledges that Holder can bear the economic risk of such Holder’s investment in this Warrant and its underlying securities and has such knowledge and experience in financial or business matters that Holder is capable of evaluating the merits and risks of its investment in this Warrant and its underlying securities and/or has a preexisting personal or business relationship with the Company and certain of its officers, directors or controlling persons of a nature and duration that enables Holder to be aware of the character, business acumen and financial circumstances of such persons.

4.4 Accredited Investor Status . Holder is an “accredited investor” within the meaning of Regulation D promulgated under the Act.

Shares issued upon any exercise or conversion hereof must be held indefinitely unless subsequently registered under the Act and qualified under applicable state securities laws, or unless exemption from such registration and qualification are otherwise available.

ARTICLE V. MISCELLANEOUS .

5.1 Term . Subject to early termination in accordance with Article 1.6, this Warrant is exercisable in whole or in part at any time and from time to time on or before the Expiration Date.

5.2 Legends . This Warrant and the Shares (and the securities issuable, directly or indirectly, upon conversion of the Shares, if any) shall be imprinted with a legend in substantially the following form:

5.3 Compliance with Securities Laws on Transfer . This Warrant and the Shares issuable upon exercise of this Warrant (and the securities issuable, directly or indirectly, upon conversion of the Shares, if any) may not be transferred or assigned in whole or in part without compliance with applicable federal and state securities laws by the transferor and the transferee (including, without limitation, the delivery of investment representation letters and legal opinions reasonably satisfactory to the Company, as reasonably requested by the Company). The Company shall not require Silicon Valley Bank (“Bank”) to provide an opinion of counsel if the transfer is to Bank’s parent company, SVB Financial Group (formerly Silicon Valley Bancshares), or any other affiliate of Bank, provided such affiliate makes representations and warranties substantially similar to those set forth in Article 4. Additionally, the Company shall also not require an opinion of counsel if there is no material question as to the availability of current information as referenced in Rule 144(c), Holder represents that it has complied with Rule 144(d) and (e) in reasonable detail, the selling broker represents that it has complied with Rule 144(f), and the Company is provided with a copy of Holder’s notice of proposed sale.

issuable directly or indirectly, upon conversion of the Shares, if any) to any transferee, provided, however, in connection with any such transfer, SVB Financial Group or any subsequent Holder will give the Company notice of the portion of the Warrant being transferred with the name, address and taxpayer identification number of the transferee and Holder will surrender this Warrant to the Company for reissuance to the transferee(s) (and Holder if applicable). The Company may refuse to transfer this Warrant or the Shares (a) to any person who directly competes with the Company, unless, in either case, the stock of the Company is publicly traded, or (b) if, in the reasonable good faith determination of the Company in consultation with its legal counsel, such transfer would not be exempt from the registration requirements of the Act.

5.5 Notices . All notices and other communications from the Company to Holder, or vice versa, shall be deemed delivered and effective when given personally or mailed by first-class registered or certified mail, postage prepaid, at such address as may have been furnished to the Company or Holder, as the case may (or on the first business day after transmission by facsimile) be, in writing by the Company or such Holder from time to time. Effective upon receipt of the fully executed Warrant and the initial transfer described in Article 5.4 above, all notices to Holder shall be addressed as follows until the Company receives notice of a change of address in connection with a transfer or otherwise:

SVB Financial Group

Attn: Treasury Department

3003 Tasman Drive, HA 200

Santa Clara, CA 95054

Telephone: 408-654-7400

Facsimile: 408-496-2405

Notice to the Company shall be addressed as follows until Holder receives notice of a change in address:


ARCA Discovery, Inc.
Attn:		Patrick Wheeler


1200 17th St., Suite 620
Denver, CO 80202
Telephone:		303-893-1598
Facsimile:		303-825-0883

5.6 Waiver . This Warrant and any term hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of such change, waiver, discharge or termination is sought.

5.7 Attorneys’ Fees . In the event of any dispute between the parties concerning the terms and provisions of this Warrant, the party prevailing in such dispute shall be entitled to collect from the other party all costs incurred in such dispute, including reasonable attorneys’ fees.

5.8 Automatic Conversion upon Expiration . In the event that, upon the Expiration Date, the fair market value of one Share (or other security issuable upon the exercise hereof) as determined in accordance with Section 1.3 above is greater than the Warrant Price in effect on such date, then this Warrant shall automatically be deemed on and as of such date to be converted pursuant to Section 1.2 above as to all Shares (or such other securities) for which it shall not previously have been exercised or converted, and the Company shall promptly deliver a certificate representing the Shares (or such other securities) issued upon such conversion to Holder.

5.9 Counterparts . This Warrant may be executed in counterparts, all of which together shall constitute one and the same agreement.

5.10 Governing Law . This Warrant shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to its principles regarding conflicts of law.

[Signature page follows.]


“COMPANY”		Date:	7/17/07

ARCA DISCOVERY, INC.

By:	/s/ Richard B. Brewer	By:	/s/ Patrick Wheeler
Name:	Richard B. Brewer	Name:	Patrick Wheeler
	(Print)		(Print)
Title:	Chairman of the Board, President or Vice President	Title:	Chief Financial Officer, Secretary, Assistant Treasurer or Assistant Secretary

“HOLDER”:

SILICON VALLEY BANK

By:	/s/ Adam Glick
Name:	Adam Glick
	(Print)
Title:	Relationship Manager

SCHEDULE 1

CAPITALIZATION TABLE

[Omitted]

APPENDIX 1

NOTICE OF EXERCISE

1. Holder elects to purchase shares of the Series B Preferred Stock of ARCA Discovery, Inc. pursuant to the terms of the attached Warrant, and tenders payment of the purchase price of the shares in full.

[or]

1. Holder elects to convert the attached Warrant into Shares/cash [strike one] in the manner specified in the Warrant. This conversion is exercised for of the Shares covered by the Warrant.

[Strike paragraph that does not apply.]

2. Please issue a certificate or certificates representing the shares in the name specified below:



Holders Name




(Address)

3. By its execution below and for the benefit of the Company, Holder hereby restates each of the representations and warranties in Article 4 of the Warrant as the date hereof.


HOLDER:



By:

Name:

Title:

(Date):

APPENDIX 2

ASSIGNMENT

For value received, Silicon Valley Bank hereby sells, assigns and transfers unto


Name:		SVB Financial Group
Address:		3003 Tasman Drive (HA-200) Santa Clara, CA 95054

Tax ID:		91-1962278

that certain Warrant to Purchase Stock issued by ARCA Discovery, Inc. (the “Company”), on July 17, 2007 (the “Warrant”) together with all rights, title and interest therein.


SILICON VALLEY BANK

By:
Name:
Title:


Date:

By its execution below, and for the benefit of the Company, SVB Financial Group makes each of the representations and warranties set forth in Article 4 of the Warrant and agrees to all other provisions of the Warrant as of the date hereof.


SVB FINANCIAL GROUP

By:
Name:
Title:

Exhibit 4.4

AMENDMENT NO. 1 TO WARRANT

PURCHASE STOCK

THIS AMENDMENT NO. 1 TO WARRANT TO PURCHASE STOCK (this “ Amendment ”) is entered into as of the 19 ^th day of February 2009, by and between ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.) and SVB Financial Group.

Recitals

A. The Holder was previously issued a Warrant to Purchase Stock dated as of July 17, 2007 (the “ Warrant ”). Capitalized terms used in this Amendment, but not otherwise defined in this Amendment, shall have the meanings assigned to them in the Warrant.

B. Dawn Acquisition Sub, Inc., a Delaware corporation and wholly-owned subsidiary of ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.), was merged with and into ARCA biopharma Colorado, Inc., a Delaware corporation (f/k/a ARCA biopharma, Inc. and ARCA Discovery, Inc.) (the “ Merger ”).

C. The Holder and ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.) desire to amend the Warrant to reflect the closing of the Merger, the exchange of the common stock of the Company (as defined below) for the common stock of ARCA biopharma Colorado, Inc., a Delaware corporation (f/k/a ARCA biopharma, Inc. and ARCA Discovery, Inc.) and assumption of the Warrant as required by Section 1.6.2(d) of the Warrant in connection with the closing of the Merger.

Amendments

1. The Warrant Price shall be $14.61 per share, subject to adjustment after the date of this Amendment in accordance with the terms of the Warrant.

2. The Number of Shares shall be 6,475, subject to adjustment after the date of this Amendment in accordance with the terms of the Warrant.

3. The Class of Stock shall be the common stock, $0.001 par value per share, of the Company.

4. The Company shall be ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.).

5. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Company:		Holder:

ARCA BIOPHARMA, INC.		SVB FINANCIAL GROUP

By:	/s/ Christopher D. Ozeroff	By:	/s/ Norman Cutler
	Christopher D. Ozeroff, Executive Vice	Print Name:	Norman Cutler
	of Business Development and General Counsel	Title:	Derivatives Manager

Exhibit 4.5

WARRANT TO PURCHASE STOCK


Company:		ARCA biopharma, Inc., a Delaware corporation
Number of Shares:		24,592
Class of Stock:		Series B-2 Preferred
Warrant Price:		$3.253 per share
Issue Date:		August 19, 2008
Expiration Date:		The 10th anniversary after the Issue Date
Credit Facility:		This Warrant is issued in connection with the Growth Capital facilities referenced in the Loan and Security Agreement between Company and Silicon Valley Bank dated July 17, 2007.

ARTICLE 1. EXERCISE .

1.6 Treatment of Warrant Upon Acquisition of Company .

1.6.1 “ Acquisition ”. For the purpose of this Warrant, “Acquisition” means any sale, exclusive license, or other disposition of all or substantially all of the assets of the Company, or any reorganization, consolidation, or merger of the Company where the holders of the Company’s securities before the transaction beneficially own less than 50% of the outstanding voting securities of the surviving entity after the transaction.

1.6.2 Treatment of Warrant at Acquisition .

(a) Upon the written request of the Company, Holder agrees that, in the event of an Acquisition that is not an asset sale and in which the sole consideration is cash, either (i) Holder shall exercise its conversion or purchase right under this Warrant and such exercise will be deemed effective immediately prior to the consummation of such Acquisition or (ii) if Holder elects not to exercise the Warrant, this Warrant will expire upon the consummation of such Acquisition. The Company shall provide Holder with written notice of its request relating to the foregoing (together with such reasonable information as Holder may request in connection with such contemplated Acquisition giving rise to such notice), which is to be delivered to Holder not less than ten (10) days prior to the closing of the proposed Acquisition.

ARTICLE 2. ADJUSTMENTS TO THE SHARES .

2.1 Stock Dividends, Splits, Etc. if the Company declares or pays a dividend on the Shares payable in common stock, or other securities, then upon exercise of this Warrant, for each Share acquired, Holder shall receive, without cost to Holder, the total number and kind of securities to which Holder would have been entitled had Holder owned the Shares of record as of the date the dividend occurred. If the Company subdivides the Shares by reclassification or otherwise into a greater number of shares or takes any other action which increase the amount of stock into which the Shares are convertible, the number of shares purchasable hereunder shall be proportionately increased and the Warrant Price shall be proportionately decreased. If the outstanding shares are combined or consolidated, by reclassification or otherwise, into a lesser number of shares, the Warrant Price shall be proportionately increased and the number of Shares shall be proportionately decreased.

2.2 Reclassification, Exchange, Combinations or Substitution . Upon any reclassification, exchange, substitution, or other event that results in a change of the number

and/or class of the securities issuable upon exercise or conversion of this Warrant, Holder shall be entitled to receive, upon exercise or conversion of this Warrant, the number and kind of securities and property that Holder would have received for the Shares if this Warrant had been exercised immediately before such reclassification, exchange, substitution, or other event. Such an event shall include any automatic conversion of the outstanding or issuable securities of the Company of the same class or series as the Shares to common stock pursuant to the terms of the Company’s Certificate of Incorporation upon the closing of a registered public offering of the Company’s common stock. The Company or its successor shall promptly issue to Holder an amendment to this Warrant setting forth the number and kind of such new securities or other property issuable upon exercise or conversion of this Warrant as a result of such reclassification, exchange, substitution or other event that results in a change of the number and/or class of securities issuable upon exercise or conversion of this Warrant. The amendment to this Warrant shall provide for adjustments which shall be as nearly equivalent as may be practicable to the adjustments provided for in this Article 2 including, without limitation, adjustments to the Warrant Price and to the number of securities or property issuable upon exercise of the new Warrant. The provisions of this Article 2.2 shall similarly apply to successive reclassifications, exchanges, substitutions, or other events.

ARTICLE 3. REPRESENTATIONS AND COVENANTS OF THE COMPANY .

3.1 Representations and Warranties . The Company represents and warrants to Holder as follows:

(a) The initial Warrant Price referenced on the first page of this Warrant is not greater than (i) the price per share at which the Shares were fast issued in an arms-length transaction in which at least $500,000 of the Shares were sold and (ii) the fair market value of the Shares as of the date of this Warrant.

3.4 No Shareholder Rights . Except as provided in this Warrant, Holder will not have any rights as a shareholder of the Company until the exercise of this Warrant.

ARTICLE 4. REPRESENTATIONS, WARRANTIES OF HOLDER . Holder represents and warrants to the Company as follows:

4.4 Accredited Investor Status . Holder is an “accredited investor” within the meaning of Regulation D promulgated under the Act.

4.5 The Act . Holder understands that this Warrant and the Shares issuable upon exercise or conversion hereof have not been registered under the Act in reliance upon a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of Holder’s investment intent as expressed herein. Holder understands that this Warrant and the Shares issued upon any exercise or conversion hereof must be held indefinitely unless subsequently registered under the Act and qualified under applicable state securities laws, or unless exemption from such registration and qualification are otherwise available.

ARTICLE 5. MISCELLANEOUS .

5.1 Term . Subject to early termination in accordance with Article 1.6, this Warrant is exercisable in whole or in part at any time and from time to time on or before the Expiration Date.

THIS WARRANT AND THE SHARES 1SSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), OR THE SECURITIES LAWS OF ANY STATE AND, EXCEPT AND PURSUANT TO THE PROVISIONS OF ARTICLE 5 BELOW, MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER SAID ACT AND APPLICABLE STATE SECURITIES LAW OR, IN THE OPINION OF LEGAL COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER OF THESE SECURITIES, SUCH OFFER, SALE OR TRANSFER, PLEDGE OR HYPOTHECATION IS EXEMPT FROM REGISTRATION.

5.3 Compliance with Securities Laws on Transfer . This Warrant and the Shares issuable upon exercise of this Warrant (and the securities Issuable, directly or indirectly, upon conversion of the Shares, if any) may not be transferred or assigned in whole or in part without compliance with applicable federal and state securities laws by the transferor and the transferee (including, without limitation, the delivery of investment representation letters and legal opinions reasonably satisfactory to the Company, as reasonably requested by the Company). The Company shall not require Silicon Valley Bank (“Bank”) to provide an opinion of counsel if the transfer is to Bank’s parent company, SVB Financial Group (formerly Silicon Valley Bancshares), or any other affiliate of Bank, provided such affiliate makes representations and warranties substantially similar to those set forth in Article 4. Additionally, the Company shall also not require an opinion of counsel if there is no material question as to the availability of current information as referenced in Rule 144(c), Holder represents that it has complied with Rule 144(d) and (e) in reasonable detail, the selling broker represents that it has complied with Rule 144(f), and the Company is provided with a copy of Holder’s notice of proposed sale.

5.4 Transfer Procedure . After receipt by Bank of the executed Warrant, Bank will transfer all of this Warrant to SVB Financial Group by execution of an Assignment substantially in the form of Appendix 2. Subject to the provisions of Article 5.3, and subject to the written consent of the Company for any transfer other than to an affiliate of Bank, and upon providing the Company with written notice, SVB Financial Group and any subsequent Holder may transfer all or part of this Warrant or the Shares issuable upon exercise of this Warrant (or the Shares issuable directly or indirectly, upon conversion of the Shares, if any) to any transferee, provided, however, in connection with any such transfer, SVB Financial Group or any subsequent Holder will give the Company notice of the portion of the Warrant being transferred with the name, address and taxpayer identification number of the transferee and Holder will surrender this Warrant to the Company for reissuance to the transferee(s) (and Holder if applicable). The Company may refuse to transfer this Warrant or the Shares (a) to any person who directly competes with the Company, unless, in either case, the stock of the Company is publicly traded, or (b) if, in the reasonable good faith determination of the Company in consultation with its legal counsel, such transfer would not be exempt from the registration requirements of the Act.

SVB Financial Group

Attn: Treasury Department

3003 Tasman Drive, HA 200

Santa Clara, CA 95054

Telephone: 408-654-7400

Facsimile: 408-496-2405

Notice to the Company shall be addressed as follows until Holder receives notice of a change in address:

ARCA biopharma, Inc.

Attn: Patrick Wheeler

8001 Arista Place, Suite 200

Broomfield, CO 80021

Telephone: 720-940-2107

Facsimile: 720-208-9261

5.9 Counterparts . This Warrant may be executed in counterparts, all of which together shall constitute one and the same agreement.

5.10 Governing Law . This Warrant shall be governed by and construed in accordance with the laws of the State of Delaware, without giving effect to its principles regarding conflicts of law.

[Signature page follows.]


“COMPANY”		Date:	8/28/08

ARCA BIOPHARMA, INC.

By:	/s/ Richard B. Brewer	By:	/s/ Patrick Wheeler
Name:	Richard B. Brewer	Name:	Patrick Wheeler
	(Print)		(Print)
Title:	Chairman of the Board, President or	Title:	Chief Financial Officer, Secretary,
	Vice President		Assistant Treasurer or Assistant Secretary


“HOLDER”

SILICON VALLEY BANK

By:		/s/ Bret J. Turner
Name:		Bret J. Turner
		(Print)
Title:		Relationship Manager

Exhibit 4.6

AMENDMENT NO. 1 TO WARRANT

PURCHASE STOCK

Recitals

A. The Holder was previously issued a Warrant to Purchase Stock dated as of August 19, 2008 (the “ Warrant ”). Capitalized terms used in this Amendment, but not otherwise defined in this Amendment, shall have the meanings assigned to them in the Warrant.

C. The Holder and ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.) desire to amend the Warrant to reflect the closing of the Merger, the exchange of the common stock of the Company (as defined below) for the common stock of ARCA biopharma Colorado, Inc., a Delaware corporation (f/k/a ARCA biopharma, Inc.) and assumption of the Warrant as required by Section 1.6.2(d) of the Warrant in connection with the closing of the Merger.

Amendments

1. The Warrant Price shall be $19.48 per share, subject to adjustment after the date of this Amendment in accordance with the terms of the Warrant.

2. The Number of Shares shall be 6,679, subject to adjustment after the date of this Amendment in accordance with the terms of the Warrant.

3. The Class of Stock shall be the common stock, $0.001 par value per share, of the Company.

4. The Company shall be ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.).

5. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Company:		Holder:

ARCA BIOPHARMA, INC.		SVB FINANCIAL GROUP

By:	/s/ Christopher D. Ozeroff	By:	/s/ Norman Cutler
	Christopher D. Ozeroff, Executive Vice of Business Development and General Counsel	Print Name:	Norman Cutler
		Title:	Derivatives Manager

Exhibit 4.7

THIS WARRANT AND THE UNDERLYING SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”). THEY MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO SUCH SECURITIES UNDER THE ACT OR AN OPINION OF COUNSEL SATISFACTORY TO THE CORPORATION THAT SUCH REGISTRATION IS NOT REQUIRED.

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 4		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, Boulder Ventures IV, L.P., with its principal office at 1900 Ninth Street, Suite 200, Boulder, CO 80302, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

This Warrant is being issued pursuant to the terms of the Note and Warrant Purchase Agreement, dated September 24, 2008, as amended by the First Amendment thereto, dated as of the date hereof, (as amended, the “ Note and Warrant Purchase Agreement ”) by and among the Corporation and the Purchasers listed on the Schedule of Purchasers thereto, as the same may be further amended from time to time (the “ Schedule of Purchasers ”). Capitalized terms used herein but not otherwise defined shall have the meanings given to them in the Note and Warrant Purchase Agreement.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

(b) “ Exercise Price ” shall mean the lesser of (i) $3.253 or (ii) the product of (x) the Parent Trading Price (as defined in the Merger Agreement) and (y) the Exchange Ratio (as defined in the Merger Agreement and determined in accordance with the methodology reflected in the Spreadsheet (as defined in the Merger Agreement)); provided, however that in no event shall the Exercise Price be less than $1.6265; and provided, further that the Exercise Price shall be subject to adjustment pursuant to the terms herein, including Section 5 below. Notwithstanding the forgoing, if the Merger (as defined below) does not close on or before March 31, 2009, the Exercise Price shall be $1.6265, subject to adjustment pursuant to the terms herein, including Section 5 below.

(c) “ Exercise Shares ” shall mean a number of shares of common stock of the Corporation (the “ Common Stock ”) issuable upon exercise of this Warrant equal to (i) one-fifth (1/5 ^th ) of such Purchaser’s Total Purchase Price (as defined in the Note and Warrant Purchase Agreement) divided by (b) the Exercise Price, rounded up to the nearest share and subject to adjustment pursuant to the terms herein, including Section 5 below.

(d) “ Merger Agreement ” shall mean that certain Agreement and Plan of Merger and Reorganization dated September 24, 2008, by and among the Corporation, Nuvelo, Inc., a Delaware corporation (the “ Parent ”) and Dawn Acquisition Sub, Inc., a Delaware corporation (the “ Merger Sub ”), pursuant to which Merger Sub will merge with and into the Corporation and the stockholders of the Corporation will receive shares of the capital stock of Parent in exchange for their capital stock of the Corporation (the “ Merger ”).

2. E XERCISE OF W ARRANT .

2.1 I N G ENERAL . The rights represented by this Warrant may be exercised in whole or in part at any time during the Exercise Period, by delivery of the following to the Corporation at its address set forth above (or at such other address as it may designate by notice in writing to the Holder):

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.

Upon the exercise of the rights represented by this Warrant, a certificate or certificates for the Exercise Shares so purchased, registered in the name of the Holder or persons affiliated with the Holder, if the Holder so designates, shall be issued and delivered to the Holder as soon as practicable after the rights represented by this Warrant shall have been so exercised.

The person in whose name any certificate or certificates for Exercise Shares are to be issued upon exercise of this Warrant shall be deemed to have become the holder of record of such shares on the date on which this Warrant was surrendered and payment of the Exercise Price was made, irrespective of the date of delivery of such certificate or certificates, except that, if the date of such surrender and payment is a date when the stock transfer books of the Corporation are closed, such person shall be deemed to have become the holder of such shares at the close of business on the next succeeding date on which the stock transfer books are open.

2.2 Net Exercise . Notwithstanding any provisions herein to the contrary, if the fair market value of one share of the Corporation’s Common Stock is greater than the Exercise Price (at the date of calculation as set forth below), in lieu of exercising this Warrant by payment of cash, the Holder may elect (the “ Conversion Right ”) to receive shares equal to the value (as

determined below) of this Warrant (or the portion thereof being canceled) by surrender of this Warrant at the principal office of the Corporation together with the properly endorsed Notice of Exercise, in which event the Corporation shall issue to the Holder a number of shares of Common Stock computed using the following formula:


X = Y (A-B) A

Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

For purposes of the above calculation, the fair market value of one share of Common Stock shall be determined by the Corporation’s Board of Directors in good faith; provided, however, that in the event that this Warrant is exercised when the Corporation’s Common Stock is traded in a public market, the fair market value of each share of Common Stock shall be the closing price of a share of Common Stock for the business day immediately before the day the Holder delivers its Notice of Exercise to the Company.

3. C OVENANTS OF THE C ORPORATION .

3.1 Covenants as to Exercise Shares . The Corporation covenants and agrees that all Exercise Shares that may be issued upon the exercise of the rights represented by this Warrant will, upon issuance, be validly issued and outstanding, fully paid and nonassessable, and free from all taxes, liens and charges with respect to the issuance thereof. The Corporation further covenants and agrees that the Corporation shall at all times during the Exercise Period have authorized and reserved, free from preemptive rights, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant. If at any time during the Exercise Period the number of authorized but unissued shares of Common Stock shall not be sufficient to permit exercise of this Warrant, the Corporation will take such corporate action as may, in the opinion of its counsel, be necessary to increase its authorized but unissued shares of Common Stock to such number of shares as shall be sufficient for such purposes.

3.2 No Impairment . Except and to the extent as waived or consented to by the Holder, the Corporation will not, by amendment of its Certificate of Incorporation or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms to be observed or performed hereunder by the Corporation, but will at all times in good faith assist in the carrying out of all the provisions of this Warrant and in the taking of all such action as may be necessary or appropriate in order to protect the exercise rights of the Holder against impairment.

3.3 Notices of Record Date . In the event of any taking by the Corporation of a record of the holders of any class of securities for the purpose of determining the holders thereof who are entitled to receive any dividend (other than a cash dividend which is the same as cash dividends paid in previous quarters) or other distribution, the Corporation shall mail to the Holder, at least ten (10) days prior to the date specified herein, a notice specifying the date on which any such record is to be taken for the purpose of such dividend or distribution.

3.4 Notice of Expiration. If this Warrant has not been fully exercised on or before the date thirty (30) days prior to the end of the Exercise Period, the Corporation shall thereafter provide Holder with at least twenty (20) days advance written notice of the date on which this Warrant is to expire. If the Corporation fails to provide such notice, the Exercise Period shall be extended until the date thirty (30) days after the date said notice is provided to Holder. If this Warrant would terminate when it could be net exercised pursuant to Section 2.2, it shall be deemed so exercised immediately prior to such termination, unless Holder states explicitly to the contrary in writing.

4. R EPRESENTATIONS OF H OLDER .

4.1 Acquisition of Warrant for Personal Account. The Holder represents and warrants that it is acquiring the Warrant solely for his, her or its account for investment and not with a view to or for sale or distribution of said Warrant or any part thereof, other than potential transfers between affiliates (including affiliate funds). The Holder also represents that the entire legal and beneficial interests of the Warrant and Exercise Shares the Holder is acquiring is being acquired for, and will be held for, his, her or its account only.

4.2 Securities Are Not Registered.

(a) The Holder understands that the Warrant and the Exercise Shares have not been registered under the Securities Act of 1933, as amended (the “ Act ”) on the basis that no distribution or public offering of the stock of the Corporation is to be effected. The Holder realizes that the basis for the exemption may not be present if, notwithstanding his, her or its representations, the Holder has a present intention of acquiring the securities for a fixed or determinable period in the future, selling (in connection with a distribution or otherwise), granting any participation in, or otherwise distributing the securities. The Holder has no such present intention.

(b) The Holder recognizes that the Warrant and the Exercise Shares must be held indefinitely unless they are subsequently registered under the Act or an exemption from such registration is available.

(c) The Holder is aware that neither the Warrant nor the Exercise Shares may be sold pursuant to Rule 144 adopted under the Act unless certain conditions are met, including, among other things, the existence of a public market for the shares, the availability of certain current public information about the Corporation, the resale following the required holding period under Rule 144 and the number of shares being sold during any three month period not exceeding specified limitations. Holder is aware that the conditions for resale set forth in Rule 144 have not been satisfied and that the Corporation presently has no plans to satisfy these conditions in the foreseeable future.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(i) The Corporation shall have received a letter secured by the Holder from the Securities and Exchange Commission stating that no action will be recommended to the Commission with respect to the proposed disposition; or

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

(iii) The Holder shall have notified the Corporation of the proposed disposition and shall have furnished the Corporation with a statement of the circumstances surrounding the proposed disposition; provided, however, that such statement will not be required if the disposition is permitted under Rule 144 of the Act, except in unusual circumstances.

(b) Notwithstanding the provisions of paragraphs (a) above, the Holder may assign this Warrant and the Exercise Shares to (i) any partner or retired partner of the Holder if Holder is a partnership, (ii) any member or former member of the Holder if Holder is a limited liability company, (iii) any affiliate, including affiliated funds or (iv) any family member or trust for the benefit of the Holder if the Holder is an individual; provided that the Corporation is given written notice thereof.

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

5.1 Adjustment of Exercise Price. In the event of changes in the outstanding Common Stock of the Corporation by reason of stock dividends, splits, recapitalizations, reclassifications, combinations or exchanges of shares, separations, reorganizations, liquidations, or the like, the number and class of shares available under the Warrant in the aggregate and the Exercise Price shall be correspondingly adjusted to give the Holder of the Warrant, on exercise for the same aggregate Exercise Price, the total number, class, and kind of shares as the Holder would have owned had the Warrant been exercised prior to the event and had the Holder continued to hold such shares until after the event requiring adjustment. The form of this Warrant need not be changed because of any adjustment in the number of Exercise Shares subject to this Warrant.

5.2 Reorganization, Reclassification, Consolidation, Merger or Sale. If any recapitalization, reclassification or reorganization of the capital stock of the Corporation, or any consolidation or merger of the Corporation with another corporation, or the sale of all or substantially all of its assets or other transaction shall be effected in such a way that holders of

the Corporation’s Common Stock shall be entitled to receive stock, securities, or other assets or property, including, without limitation, upon conversion of such Common Stock (an “ Organic Change ”), then, as a condition of such Organic Change, lawful and adequate provisions shall be made by the Corporation whereby the Holder hereof shall thereafter have the right to purchase and receive (in lieu of the shares of the Common Stock of the Corporation immediately theretofore purchasable and receivable upon the exercise of the rights represented hereby) such shares of stock, securities or other assets or property as may be issued or payable with respect to or in exchange for a number of outstanding shares of such Common Stock equal to the number of shares of such stock immediately theretofore purchasable and receivable upon the exercise of the rights represented hereby. In the event of any Organic Change, appropriate provision shall be made by the Corporation with respect to the rights and interests of the Holder of this Warrant to the end that the provisions hereof (including, without limitation, provisions for adjustments of the Exercise Price and of the number of shares purchasable and receivable upon the exercise of this Warrant) shall thereafter be applicable, in relation to any shares of stock, securities or assets thereafter deliverable upon the exercise hereof and following such Organic Change the Corporation or its successor shall promptly issue to Holder an amendment to this Warrant reflecting such adjustments.

5.3 Certain Events. If any change in the outstanding Common Stock of the Corporation or any other event occurs as to which the other provisions of this Section 5 are not strictly applicable or if strictly applicable would not fairly protect the purchase rights of the Holder of the Warrant in accordance with such provisions, then the Board of Directors of the Corporation shall make an adjustment in the number and class of shares available under the Warrant, the Exercise Price or the application of such provisions, so as to protect such purchase rights as aforesaid. The adjustment shall be such as to give the Holder of the Warrant upon exercise for the same aggregate Exercise Price the total number, class and kind of shares as he would have owned had the Warrant been exercised prior to the event and had he continued to hold such shares until after the event requiring adjustment.

6. F RACTIONAL S HARES . No fractional shares shall be issued upon the exercise of this Warrant as a consequence of any adjustment pursuant hereto. All Exercise Shares (including fractions) issuable upon exercise of this Warrant may be aggregated for purposes of determining whether the exercise would result in the issuance of any fractional share. If, after aggregation, the exercise would result in the issuance of a fractional share, the Corporation shall, in lieu of issuance of any fractional share, pay the Holder otherwise entitled to such fraction a sum in cash equal to the product resulting from multiplying the then current fair market value of an Exercise Share by such fraction.

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

8. T RANSFER OF W ARRANT . Subject to applicable laws and any restrictions on transfer set forth in this Warrant, this Warrant and all rights hereunder are transferable, by the Holder in person or by duly authorized attorney, upon delivery of this Warrant and the form of assignment attached hereto to any transferee designated by Holder.

9. L OST , S TOLEN , M UTILATED OR D ESTROYED W ARRANT . The Corporation covenants to the holder hereof that, upon receipt of evidence reasonably satisfactory to the Corporation of the loss, theft, destruction or mutilation of this Warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to the Corporation, or in the case of any such mutilation, upon surrender and cancellation of such Warrant or stock certificate, the Corporation will make and deliver a new Warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated Warrant or stock certificate.

10. N OTICES , ETC . Any notice required or permitted under this Warrant shall be given in writing and shall be deemed effectively given: (a) upon personal delivery to the party to be notified, (b) when sent by confirmed facsimile if sent during normal business hours of the recipient; if not, then on the next business day, (c) five (5) business days after having been sent by registered or certified mail, return receipt requested, postage prepaid, or (d) one (1) business day after deposit with a nationally recognized overnight courier, specifying next day delivery, with written verification of receipt. All communications shall be sent to (i) the Corporation at ARCA biopharma, Inc., 8001 Arista Place, Suite 200, Broomfield, CO 80021, Attention: Chief Executive Officer and General Counsel; or to (ii) a Purchaser at his, her or its address shown on the Schedule of Purchasers, or at such other address as any such party may designate by ten (10) days advance written notice to the other parties hereto.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

12. G OVERNING L AW . This Warrant and all rights, obligations and liabilities hereunder shall be governed and construed under the laws of the State of Colorado in all respects as such laws are applied to agreements among Colorado residents entered into and performed entirely within Colorado, without giving effect to conflict of law principles thereof. The Corporation and Holder agree that any action brought by any party under or in relation to this Warrant, including without limitation to interpret or enforce any provision of this Warrant, shall be brought in, and each agrees to and does hereby submit to the jurisdiction and venue of, any state or federal court located in the County of Denver, Colorado.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , I NC .

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE TO W ARRANT

NOTICE OF EXERCISE

TO:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

(1) ¨ The undersigned hereby elects to purchase shares of the Common Stock of ARCA biopharama, Inc. (the “ Company ”) pursuant to the terms of the attached Warrant, and tenders herewith payment of the exercise price in full, together with all applicable transfer taxes, if any.

¨ The undersigned hereby elects to purchase shares of the Common Stock of the Company pursuant to the terms of the net exercise provisions set forth in Section 2.1 of the attached Warrant, and shall tender payment of all applicable transfer taxes, if any.

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

NOTE : The signature to this Assignment Form must correspond with the name as it appears on the face of the Warrant, without alteration or enlargement or any change whatsoever. Officers of corporations and those acting in a fiduciary or other representative capacity should file proper evidence of authority to assign the foregoing Warrant.

Exhibit 4.8

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

THIS AMENDMENT NO. 1 TO WARRANT TO PURCHASE COMMON STOCK (this “ Amendment ”) is entered into as of the 19 ^th day of February 2009, by and between ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.) and Boulder Ventures IV, L.P.

Recitals

A. The Holder was previously issued a Warrant to Purchase Common Stock dated as of October 10, 2008 (the “ Warrant ”). Capitalized terms used in this Amendment, but not otherwise defined in this Amendment, shall have the meanings assigned to them in the Warrant.

B. The Holder and ARCA biopharma, Inc., a Delaware corporation (f/k/a Nuvelo, Inc.) desire to amend the Warrant to reflect the closing of the Merger and the exchange of the common stock of the Corporation (as defined below) for the common stock of ARCA biopharma Colorado, Inc., a Delaware corporation (f/k/a ARCA biopharma, Inc.) in connection with such closing.

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 1,897 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		Boulder Ventures IV, L.P.

		By: BV Partners IV, L.L.C., its General Partner

By:	/s/ Christopher D. Ozeroff	By:	/s/ Kyle Lefkoff
	Christopher D. Ozeroff, Executive Vice	Print Name: Kyle Lefkoff
	of Business Development and General Counsel	Title:	Managing Member

Exhibit 4.9

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 5		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, Boulder Ventures IV (Annex), L.P., with its principal office at 1900 Ninth Street, Suite 200, Boulder, CO 80302, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

2. E XERCISE OF W ARRANT .

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.


X = Y (A-B) A
Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

3. C OVENANTS OF THE C ORPORATION .

4. R EPRESENTATIONS OF H OLDER .

4.2 Securities Are Not Registered.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , I NC .

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE TO W ARRANT

NOTICE OF EXERCISE

TO:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

Exhibit 4.10

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

Recitals

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 28,651 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		Boulder Ventures IV (Annex), L.P.

		By: BV Partners IV, L.L.C., its General Partner

By:	/s/ Christopher D. Ozeroff	By:	/s/ Kyle Lefkoff
	Christopher D. Ozeroff, Executive Vice of Business Development and General Counsel	Print Name: Kyle Lefkoff Title: Managing Member

Exhibit 4.11

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 2		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, InterWest Partners IX, LP, with its principal office at 2710 Sand Hill Road, Second Floor, Menlo Park, CA 94025, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

2. E XERCISE OF W ARRANT .

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.


X = Y (A-B) A

Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

3. C OVENANTS OF THE C ORPORATION .

4. R EPRESENTATIONS OF H OLDER .

4.2 Securities Are Not Registered.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , I NC .

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE TO W ARRANT

NOTICE OF EXERCISE

TO:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

Exhibit 4.12

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

Recitals

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 30,015 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		InterWest Partners IX, LP

		By: InterWest Management Partners IX, LLC

By:	/s/ Christopher D. Ozeroff	By:	/s/ Linda Grais
	Christopher D. Ozeroff, Executive Vice of Business Development and General Counsel		Linda Grais, Venture Member

Exhibit 4.13

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 3		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, Atlas Venture Fund VII, L.P., with its principal office at 890 Winter Street, Suite 320, Waltham, MA 02451, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

2. E XERCISE OF W ARRANT .

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.


X = Y (A-B) A

Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

3. C OVENANTS OF THE C ORPORATION .

4. R EPRESENTATIONS OF H OLDER .

4.2 Securities Are Not Registered.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , I NC .

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE TO W ARRANT

NOTICE OF EXERCISE

TO:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

Exhibit 4.14

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

Recitals

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 75,449 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		Atlas Venture Fund VII, L.P.

		By: Atlas Venture Associates VII, L.P. its General Partner

		By: Atlas Venture Associates VII, Inc. its General Partner

By:	/s/ Christopher D. Ozeroff	Signature:	/s/ Kristen Laguerre
	Christopher D. Ozeroff, Executive Vice	Name: Kristen Laguerre
	of Business Development and General Counsel	Title: Vice President

Exhibit 4.15

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 6		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, The Peierls Foundation, Inc., with its principal office at c/o U.S. Trust Company of N.Y.,114 West 47th Street, New York, NY 10036, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

2. E XERCISE OF W ARRANT .

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.


X = Y (A-B) A

Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

3. C OVENANTS OF THE C ORPORATION .

4. R EPRESENTATIONS OF H OLDER .

4.2 Securities Are Not Registered.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , I NC .

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE T O W ARRANT

NOTICE OF EXERCISE

TO:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

Exhibit 4.16

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

Recitals

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 6,159 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		The Peierls Foundation, Inc.

By:	Christopher D. Ozeroff	Signature:	/s/ E. Jeffrey Peierls
	Christopher D. Ozeroff, Executive Vice	Name: E. Jeffrey Peierls
	of Business Development and General Counsel	Title: President

Exhibit 4.17

ARCA BIOPHARMA , I NC .

WARRANT TO PURCHASE COMMON STOCK


No. CW – 1		October 10, 2008

Void After October 10, 2013

This certifies that, for value received, Skyline Venture Partners Qualified Purchaser Fund IV, L.P., with its principal office at 525 University Ave, Suite 520, Palo Alto, CA 94301, or its assigns (the “ Holder ” or “ Purchaser ”), is entitled to subscribe for and purchase at the Exercise Price (as defined below) from ARCA biopharma, Inc., a Delaware corporation, with its principal office at 8001 Arista Place, Suite 200, Broomfield, Colorado 80021 (the “ Corporation ”), up to a number of Exercise Shares (as defined below), upon the terms and subject to the adjustments as provided herein.

1. Definitions . As used herein, the following terms shall have the following respective meanings:

(a) “ Exercise Period ” shall mean the time period commencing with the date of this Warrant and ending five (5) years from date of this Warrant, unless sooner terminated as provided below.

2. E XERCISE OF W ARRANT .

(a) an executed Notice of Exercise in the form attached hereto;

(b) payment of the Exercise Price either (i) in cash or by check, or (ii) by cancellation of indebtedness, or (iii) pursuant to Section 2.1 below; and

(c) this Warrant.


X = Y (A-B) A

Where X = the number of shares of Common Stock to be issued to the Holder

Y =		the number of shares of Common Stock purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being canceled (at the date of such calculation)

A =		the fair market value of one share of the Corporation’s Common Stock (at the date of such calculation)

B =		Exercise Price (as adjusted to the date of such calculation)

3. C OVENANTS OF THE C ORPORATION .

4. R EPRESENTATIONS OF H OLDER .

4.2 Securities Are Not Registered.

4.3 D ISPOSITION OF W ARRANT AND E XERCISE S HARES .

(a) The Holder further agrees not to make any disposition of all or any part of the Warrant or Exercise Shares in any event unless and until:

(ii) There is then in effect a registration statement under the Act covering such proposed disposition and such disposition is made in accordance with said registration statement; or

5. A DJUSTMENT OF E XERCISE P RICE AND E XERCISE S HARES ; E FFECT OF O RGANIC C HANGES .

7. N O S TOCKHOLDER R IGHTS . This Warrant in and of itself shall not entitle the Holder to any voting rights or other rights as a stockholder of the Corporation.

11. A CCEPTANCE . Receipt of this Warrant by the Holder shall constitute acceptance of and agreement to all of the terms and conditions contained herein.

[Signature Page Follows]

I N W ITNESS W HEREOF , the Corporation has caused this Warrant to be executed by its duly authorized officer as of October 10, 2008.


ARCA BIOPHARMA , INC.

By:		/s/ Christopher D. Ozeroff
Print Name: Christopher D. Ozeroff
Title:		EVP Business Development & General Counsel

S IGNATURE P AGE T O W ARRANT

NOTICE OF EXERCISE


TO:		ARCA biopharma, Inc.
		8001 Arista Place, Suite 200
		Broomfield, CO 80021
		Attention: Chief Executive Officer and General Counsel

(2) Please issue a certificate or certificates representing said shares of Common Stock in the name of the undersigned or in such other name as is specified below:




(Name)




(Address)


(Date)				(Signature)


				(Print name)

ASSIGNMENT FORM

(To assign the foregoing Warrant, execute this form and supply required

information. Do not use this form to purchase shares.)

F OR V ALUE R ECEIVED , the foregoing Warrant and all rights evidenced thereby are hereby assigned to

Name: ________________________________________________________________________________________________

(Please Print)

Address: ______________________________________________________________________________________________

(Please Print)

Dated:

Holder’s

Signature: _____________________________________________________________________________________________

Holder’s

Address: _____________________________________________________________________________________________

Exhibit 4.18

AMENDMENT NO. 1 TO WARRANT

PURCHASE COMMON STOCK

Recitals

Amendments

1. The definition of the term “Exercise Price” in Section 1(b) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (b) “ Exercise Price ” shall mean $9.7406, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

2. The definition of the term “Exercise Shares” in Section 1(c) of the Warrant shall be deleted in its entirety and replaced with the following:

“ (c) “ Exercise Shares ” shall mean 37,486 shares of common stock of the Corporation (the “ Common Stock ”) issuable upon the exercise of the Warrant, subject to adjustment pursuant to the terms of the Warrant, including Section 5 of the Warrant.”

3. The following defined term shall be added to Section 1 of the Warrant:

“ (e) “ Corporation ” shall mean ARCA biopharma, Inc. a Delaware corporation (f/k/a Nuvelo, Inc.).”

4. Except for revisions expressly set forth in this Amendment, the parties hereby ratify and confirm the terms of the Warrant in their entirety.

IN WITNESS WHEREOF, the undersigned have executed this Amendment to be effective as of the date first set forth above.


Corporation:		Holder:

ARCA BIOPHARMA, INC.		Skyline Venture Partners Qualified Purchaser Fund IV, L.P.

		By:	Skyline Venture Management IV, LLC
		Its General Partner

By:	/s/ Christopher D. Ozeroff	By:	/s/ John G. Freund
	Christopher D. Ozeroff, Executive Vice of Business Development and General Counsel	John G Freund, Managing Director

Exhibit 10.9

ARISTA PLACE

OFFICE LEASE

ARISTA PLACE, LLC

LANDLORD

AND

ARCA DISCOVERY, INC.

TENANT

LEASE

THIS LEASE (this “Lease”) is entered into by Landlord and Tenant as described in the following Basic Lease Information on the Date which is set forth for reference only in the following Basic Lease Information.

Landlord and Tenant agree:

ARTICLE 1

Basic Lease Information

1.1 Terms . In addition to the terms which are defined elsewhere in this Lease, the following defined terms are used in this Lease:

(a) DATE: February 8, 2008.

(b) LANDLORD: Arista Place, LLC, a Colorado limited liability company.

(d) BUILDING: The building known as 8001 Arista Place, Broomfield, Colorado 80021 as shown on the site plan attached hereto as Exhibit A and of which the Premises are a part.

(e) LAND: The real property legally described on Exhibit B .

(f) RENTABLE AREA: The “Rentable Area” of the Premises and any other space in the Building shall be determined pursuant to the Standard Method for Measuring Floor Area in Office Buildings, ANSI/BOMA Z65.1-1996, as modified for specific application for the Building.

(g) PREMISES: A portion of the second (2nd) floor of the Building comprising approximately 15,000 square feet of Rentable Area as depicted on Exhibit A-1 together with the dedicated, non-exclusive parking in the Parkade parking structure garage adjacent to the Building; provided , however , that the Rentable Area of the Premises shall be subject to adjustment based on the actual measurements made by Landlord’s Building architect and pursuant to a certificate executed by Landlord’s Building architect certifying such adjustment.

(h) TERM: Five (5) years, beginning on the Commencement Date and expiring on the Termination Date. Tenant has the right to extend the Term pursuant to the terms of Exhibit C attached hereto and incorporated herein by this reference, and any Extended Terms (as defined in Exhibit C) that are properly exercised by Tenant shall be deemed part of the “Term” for all purposes hereof

(i) COMMENCEMENT DATE: The later of (a) March 19, 2008, or (b) the date that Landlord delivers to Tenant, and Tenant accepts from Landlord, the Premises with Landlord’s Work (as hereinafter defined) Substantially Completed (as hereinafter defined).

(j) RENT COMMENCEMENT DATE: The earlier of (a) the date that is seventy-five (75) days after the Commencement Date, and (b) the date that Tenant (or any person claiming by, through or under Tenant) occupies any portion of the Premises for the conduct of its business. Once the Rent Commencement Date is determined, the parties shall, at the request of either Landlord or Tenant, execute a certificate memorializing the Commencement Date, the Rent Commencement Date, the Termination Date, the Rentable Area, and the Fixed Monthly Rent schedule.

(k) TERMINATION DATE: The last day of the month in which the Fifth (5th) anniversary of the Rent Commencement Date occurs.

(l) BASE RENT:


Months		Rate
Months 1-12:		$15.50/RSF/YrNNN
Months 13-24:		$15.97/RSF/YrNNN
Months 25-36:		$16.45 RSF/YrNNN
Months 37-48:		$16.94/RSF/YrNMM
Months 49-60:		$17.45/RSF/YrNNN

(m) SECURITY DEPOSIT: An amount equal to three months of the Base Rent payable by Tenant on the first Lease Year, and due upon the execution of this Lease.

(n) PROPERTY: The Land and the improvements and the Building located on the Land.

(o) TENANT’S SHARE: For costs attributable to the Building and the Project (as reasonably determined by Landlord and evidenced by appropriate documentation), the quotient obtained by dividing the Rentable Area of the Premises by the Rentable Area of the Building, and estimated to be $9.50 per rentable square foot on an annual basis for the first Lease Year (as hereinafter defined).

(p) PERMITTED USE: Operation of an office for conducting the business activities incident to general office use, and all uses ancillary to such business, and for no other purpose.

(q) LANDLORD’S BROKER: CB Richard Ellis.

(r) TENANT’S BROKER: Catalyst Planning Group, LLC.

(s) RENT: Base Rent, Additional Rent and any other amounts which Tenant is required to pay under this Lease.

(t) COMMON AREAS: Those areas defined as such in Section 8.1.

(u) LANDLORD’S ADDRESS (for notices pursuant to Section 17.1):

Arista Place, LLC

Attention: David Hostetler

555 Eldorado Blvd., Suite 200

Broomfield, CO 80021

(v) TENANT’S ADDRESS (for notices pursuant to Section 17.1):

Before the Commencement Date:

Area Discovery, Inc.

Attention: Pat Wheeler

1200 17th Street, Suite 620

Denver, CO 80202

After the Commencement Date:

At the Premises

Attention: Pat Wheeler, Vice President Finance

(w) PROJECT: Arista, of which the Building is a part.

(x) GUARANTOR: None.

(y) LEASE YEAR: A twelve (12) month period, except for the first Lease Year, which shall include any partial month occurring at the beginning of the Term. The first Lease Year commences on the Rent Commencement Date, the second Lease Year commences on the first day of the month following the first anniversary of the month in which the Rent Commencement Date occurs, and each subsequent Lease Year commences on the day after the end of the previous Lease Year.

(z) LANDLORD’S WORK: The work as described on Exhibit D-1 attached hereto.

(aa) SUBSTANTIAL COMPLETION: “Substantial Completion,” “Substantially Completed” or words of similar import means that Landlord’s Work has been completed in accordance with the provisions of Exhibit D-1, attached hereto except for details or adjustments that do not interfere with Tenant’s construction of Tenant’s Improvements (as hereinafter defined) in such a manner as to delay Tenant’s Improvements as reasonably determined by Tenant’s project manager in conjunction with Landlord’s project manager. Substantial Completion, for purposes of achieving the targeted Commencement Date and the Rent Commencement Date shall exclude (a) those areas of work that might be impaired by and which are not essential to Tenant’s Improvements, including but not limited to finish work in the lobby, elevators, bathrooms and security, and (b) other items of Landlord’s work which, if delayed, would benefit or improve Tenant’s scheduling of Tenant’s Work, including. without limitation, delivering the Premises drywalled.

1.2 Exhibits . The following exhibits are attached to this Lease and are made part of this Lease:


EXHIBIT A		Site Plan/Building

EXHIBIT A-1		Premises

EXHIBIT B		Legal Description of Property

EXHIBIT C		Option to Extend Term

EXHIBIT D		Work Letter Agreement

EXHIBIT D-1		Landlord’s Work

EXHIBIT E		Rules and Regulations

ARTICLE 2

Demise and Commencement

2.1 Demise; Tender . Landlord hereby leases to Tenant and Tenant hereby leases and hires from Landlord the Premises, for the Term, at the rental, and upon all of the conditions set forth in this Lease. No easement for light, view or air is included in the lease of the Premises hereby made. Landlord will tender the Premises to Tenant upon the Commencement Date.

2.2 Term . The duration of this Lease shall be the Term. The Term will commence on the Commencement Date and expire on the Termination Date.

2.3 Right of First Refusal . Provided that Tenant is not in default under this Lease beyond any applicable cure period, Tenant shall have a right of first refusal to lease all or any portion of approximately 8,400 square feet of contiguous space on the second floor of the Building (the “Second Floor Additional Space”), subject to the following terms and conditions:

(a) Prior to Landlord entering into a lease for all or any part of the Second Floor Additional Space with a third party (the “ROFR Space”), Landlord shall first offer in writing such ROFR Space for lease to Tenant on the same terms and conditions quoted to such third party (“Landlord’s Offer”).

(b) Within ten (10) business days after Tenant receives said offer from Landlord, Tenant shall either accept or reject such offer by written notice to Landlord. Failure by Tenant to deliver to Landlord a written acceptance thereof within such period shall be deemed a rejection by Tenant of such offer.

(c) If Tenant rejects or is deemed to have rejected said offer, this right of first refusal with respect to the ROFR Space shall be deemed to have terminated and Landlord shall thereafter be entitled to lease all or any portion of the ROFR Space to such third party upon the same terms and conditions as specified in Landlord’s Offer: provided , however , that: (i) said right of first refusal shall remain in effect if Landlord does not consummate a lease with the third party within ninety (90) days after Tenant receives Landlord’s Offer; (ii) Landlord shall have no right to consummate a lease with a third party for all or any portion of the ROFR Space on terms and conditions that are different than those in Landlord’s Offer; and (iii) nothing shall affect Tenant’s right of first refusal to any Second Floor Additional Space not part of the ROFR Space.

(d) If Tenant accepts said offer in accordance with the provisions hereof, Landlord and Tenant shall thereupon execute an amendment to this Lease adding the ROFR Space to this Lease in accordance with the terms and conditions of Landlord’s Offer plus a tenant improvement allowance of up to Thirty-Five Dollars ($35) per rentable square foot of the ROFR Space for completion of wall to wall improvements by Tenant pursuant to a work letter agreement reasonable acceptable, in form and substance, to Landlord and Tenant. If Tenant fails to execute said amendment within ten (10) business days after Landlord furnishes same to Tenant, the acceptance of Landlord’s offer shall be deemed to have been rejected by Tenant and thereupon the provisions of subparagraph (c) above shall apply. If Tenant rejects Landlord’s offer, or if Tenant is deemed to have rejected such offer, Tenant’s right of first refusal to lease the ROFR Space shall immediately terminate and shall be of no further force or effect.

(e) Prior to Landlord’s execution of the Lease amendment, Tenant shall furnish to Landlord current financial statements of Tenant prepared by a certified public accountant prepared in accordance with generally accepted accounting principles. As a condition of Landlord’s adding the ROFR Space to the Lease, Landlord shall have the right to approve the financial condition of Tenant which approval Landlord shall not unreasonably withhold, condition or delay; provided , however , that Landlord’s approval shall not be required if the financial condition of Tenant at such time is equal or greater than the financial condition of Tenant as of the Date. If the Landlord has the right to approve the financial condition of Tenant pursuant to the immediately preceding sentence and the Landlord does not approve the financial condition of Tenant with respect to such ROFR Space, then Tenant’s right of first refusal with respect to such ROFR Space shall terminate and immediately be of no further force or effect with respect to such ROFR Space; provided , however , that nothing shall affect Tenant’s right of first refusal to any Second Floor Additional Space not part of the ROFR Space.

2.4 Right of First Offer .

(a) Provided that Tenant is not in default of its obligations under this Lease, during the Term hereof, Tenant shall have the right of first offer to lease 100% of the space in the 8181 Arista Place Building, with the exception of the first floor retail space (the “Additional Space”). Landlord shall give Tenant written notice of the availability of any portion of the Additional Space (such portion, the “ROFO Space”) and Landlord’s good-faith estimate of the market net effective rent at which such space will be offered. Tenant shall have ten (10) business days from the receipt of Landlord’s notice to notify Landlord in writing whether it will lease the ROFO Space at the rent specified in Landlord’s notice. In the event Tenant declines the offer to lease the ROFO Space or fails to notify Landlord within said ten (10) business days, Tenant’s right of first offer with respect to that ROFO Space shall be null and void and of no further force and effect, and Landlord shall be free to lease such ROFO space to any person or entity upon any terms and for any purpose; provided , however , that: (i) said right of first offer shall remain in effect if Landlord does not consummate a lease with a third party within ninety (90) days after “Tenant receives Landlord’s notice; and (ii) if Landlord desires to lease the ROFO Space at a rental that is less than that specified in Landlord’s notice to Tenant (or Landlord provides such monetary incentives to such other tenant as to make such rental on a net basis less than that specified in Landlord’s notice to Tenant), then Landlord shall be obligated to present a new offer to Tenant and Tenant shall have the same time period to accept such new offer as Landlord’s original offer,

(b) If Tenant accepts said offer in accordance with the provisions hereof, Landlord and Tenant shall thereupon execute an amendment to this Lease adding the ROFO Space to this Lease in accordance

with the terms and conditions of Landlord’s notice plus a tenant improvement allowance of up to Thirty-Five Dollars ($35) per rentable square foot of the ROFO Space for completion of wall to wall improvements by Tenant pursuant to a work letter agreement reasonably acceptable, in form and substance, to Landlord and Tenant.

(c) Prior to Landlord’s execution of the Lease amendment, Tenant shall furnish to Landlord current financial statements of Tenant prepared by a certified public accountant prepared in accordance with generally accepted accounting principles, As a condition of Landlord’s adding the ROFO Space to the Lease, Landlord shall have the right to approve the financial condition of Tenant which approval Landlord shall not unreasonably withhold, condition or delay; provided , however , that Landlord’s approval shall not be required if the financial condition of Tenant at such time is equal or greater than the financial condition of Tenant as of the Date. If the Landlord has the right to approve the financial condition of Tenant pursuant to the immediately preceding sentence and the Landlord does not approve the financial condition of Tenant with respect to such ROFO Space, then Tenant’s right of first refusal with respect to such ROFO Space shall terminate and immediately be of no further force or effect with respect to such ROFO Space; provided , however , that nothing shall affect Tenant’s right of first offer to any Additional Space not part of the ROFO Space.

2.5 Landlord’s Work .

(a) On the Commencement Date, Landlord shall deliver to Tenant, subject to Tenant’s acceptance, the Premises with Landlord’s Work Substantially Completed. Landlord shall give Tenant at least ten (10) days prior written notice prior to the date on which Landlord intends to deliver the Premises to Tenant with Landlord’s Work Substantially Completed.

(b) Notwithstanding anything to the contrary contained in this Lease, if:

(i) the Commencement Date has not occurred because Landlord has not Substantially Completed Landlord’s Work and delivered the Premises to Tenant by March 19, 2008, (the “Delivery Date”), then the Rent Commencement Date shall be extended by one day for each day occurring during the period commencing on the Delivery Date through and including the occurrence of the Commencement Date;

(ii) Landlord has not delivered to Tenant a certificate of occupancy on the core shell of the Building from the appropriate governmental agency (the “Certificate”) by June 2, 2008 (the “Outside Delivery Date”), then the Rent Commencement Date shall be extended by two (2) days for each day occurring during the period commencing on the Outside Delivery Date through and including the date that Landlord delivers to Tenant such Certificate;

(iii) Landlord has not delivered to Tenant the Certificate by June 12, 2008, then Landlord shall be responsible for, and hereby agrees to indemnify and hold Tenant harmless against: (A) any and all claims, costs and liabilities, including attorneys’ fees, court costs, and other expenses of litigation, arising out of or in connection with Tenant’s holdover in Tenant’s current space; (B) any and all expenses incurred by Tenant on account of Tenant’s expedited move to the Premises which are in excess of normal moving expenses; and (C) if Tenant has notified Landlord by May 25, 2008 that Tenant will be required to relocate from its current space to temporary space after May 31, 2008, then Landlord shall be responsible for all costs and expenses incurred by Tenant in connection with such temporary space after June 12, 2008, including, without limitation, rent and moving costs; and

(iv) Landlord has not delivered to Tenant the Certificate or Landlord has not delivered the Premises with Landlord’s Work Substantially Completed by June 30, 2008, then Tenant shall have the right, in addition to any other rights hereunder, to terminate this Lease upon written notice to Landlord.

(c) Landlord and Tenant acknowledge and agree that if Landlord is unable to meet any of the dates set forth in Section 2.5(b) above as a result of a delay caused solely (i) by Tenant, or (ii) Tenant’s contractor (“Tenant Delay”), then Landlord shall be afforded additional time to meet such dates in the exact proportion to the delay caused by Tenant or Tenant’s contractor. If any date called for herein falls upon a Saturday, Sunday or legal holiday, such date shall be moved to the next immediately following business day.

2.6 Hours . During the term, Landlord shall furnish heating, ventilating and air conditioning to the Premises between the hours of 7:00 a.m. and 6:00 p.m. Monday through Friday (holidays excepted) and 8:00 a.m. to 12:00 p.m. on Saturdays. Landlord, at Tenant’s sole cost and expense, shall provide overtime air conditioning to the Premises as requested by Tenant in advance during the Term and Tenant shall reimburse Landlord for Landlord’s reasonable costs for the supply of such overtime air conditioning, which reasonable costs shall be billed to Tenant on a monthly basis. For purposes of the preceding sentence, “reasonable costs” shall not include amortization or depreciation of any equipment that provides such overtime air conditioning. Landlord shall provide Tenant with reasonable documentation evidencing such costs. The Building will offer a 24 hour card key access to lobby entries and elevators.

ARTICLE 3

Base Rent, Additional Rent, Taxes and Security Deposit

3.1 Base Rent . On or before the first day of each and every month during the Term, commencing on the Rent Commencement Date, Tenant agrees to pay to Landlord the Base Rent, without notice or demand, in advance. Base Rent for any period of less than 1 month shall be prorated based upon the total number of days in the month in which such period occurs. Base Rent and all other Rent due hereunder shall be paid to Landlord, without deduction or offset, in lawful money of the United States of America at Landlord’s Address or at such other place as Landlord may from time to time designate in writing.

3.2 Additional Rent . In addition to the Base Rent, Tenant shall pay to Landlord Tenant’s Share of Common Area Expenses, Taxes, and Insurance Costs (as reasonably determined by Landlord) for each Lease Year, or portion thereof (such costs being collectively referred to herein as “Additional Rent”).

3.3 Additional Rent Payment . Tenant shall pay to Landlord each month of each Lease Year of the Term 1/12th of the estimated amount of Additional Rent owed by Tenant for such Lease Year pursuant to Section 3.2. During the final month of each Lease Year during the Term, or as soon thereafter as practicable, Landlord shall give Tenant written notice of the Additional Rent for the ensuing Lease Year in additional to reasonable documentary evidence to Tenant of such Additional Rent (Upon Tenant’s request, Landlord shall provide Tenant such documentary evidence for the first Lease Year prior to Tenant being obligated to pay Additional Rent for such first Lease Year). On or before the first day of each month during the ensuing Lease Year, Tenant shall pay to Landlord 1/12th of such Additional Rent; provided , however , that if such notice is not given during the final month of the Lease Year, Tenant shall continue to pay on the basis of the prior Lease Year’s Additional Rent until the month after such notice is given. In the month Tenant first makes a payment based upon the new Additional Rent, Tenant shall pay to Landlord the difference between the amount payable based on the new Additional Rent and the amount actually paid by Tenant for each month which has elapsed since the end of the prior Lease Year. Within one hundred twenty (120) days after the end of each Lease Year, or a reasonable time thereafter, Landlord shall deliver to Tenant a statement of Additional Rent for such Lease Year, along with reasonable documentary evidence to Tenant, and Tenant shall pay Landlord or Landlord shall credit Tenant (or, if such adjustment is at the end of the Term, pay Tenant), within thirty (30) days of receipt of such statement, the amount of any excess or deficiency in Tenant’s payment of its portion of Additional Rent for the Lease Year.

3.4 Common Area Expenses . The term “Common Area Expenses” means, with respect to any given Lease Year during the Term, all of Landlord’s costs and expenses that are reasonably incurred and directly attributable to the operation, maintenance, management, and repair of the Building, alleyways, parking facilities and Common Areas as determined under generally accepted accounting principles consistently applied, and calculated on an accrual basis, including, without limitation, reasonable and out-of-pocket expenses and fees imposed by any governing owners or building association (i.e. the Arista Master Association), as well as reasonable and out-of-pocket costs of cleaning, window washing, maintaining window coverings, landscaping, elevator maintenance, lighting, heating, air conditioning, paving, painting, and repairing the Building or any portion of it, maintaining any associated or adjoining alleyways or parking facilities, removing snow and ice, trash removal, providing security, management fees paid to third-party contractors, providing seasonal holiday decorations, providing public liability, property damage, fire and extended coverage and such other insurance as Landlord deems appropriate (but

excluding terrorism insurance), wages, salaries and compensation of employees who are not above the level of building manager, consulting, accounting, legal, janitorial, maintenance, guard, fire protection, fire hydrant and other services, the actual cost, without profit, of power (as to Common Areas only), water, waste disposal and other utilities, if such utilities are not separately metered, licenses and permit fees, the total amounts paid by Landlord in satisfaction of any assessment made by any building or property owners’ association for the purpose of providing any services or benefits to the Premises or, to the extent enjoyed by Tenant or its occupants, the Building generally, depreciation on personal property and equipment used in the operation or maintenance of the Building and rent paid for leasing such equipment, real and personal property taxes and assessment (and any tax levied in whole or in part in lieu of or in addition to such property taxes) on the Building, the related real property or Landlord’s personal property used in the operation or maintenance of the Building (except for Taxes or as otherwise specified below), the pro-rata share of costs of maintenance or operation of the Project, and any other costs, charges and expenses which are reasonably regarded as management, maintenance and operating expenses of Landlord for the Building, plus all reasonable costs (depreciated over the useful life of the item as Landlord will reasonably determine in accordance with sound management accounting principles, together with market interest thereon) of any capital improvements which arc made to the Building by Landlord (a) for the purpose of reducing the costs described in this paragraph, or (b) after the date of this Lease and which are required under any governmental law or regulation. Notwithstanding the foregoing, Common Area Expenses will not include:

(a) costs of a capital nature including capital improvements, capital repairs, capital equipment, and capital tools, as determined under generally accepted accounting principles consistently applied;

(b) rentals and other related expenses incurred in leasing air conditioning systems, elevators, or other equipment ordinarily considered to be of a capital nature;

(c) depreciation and amortization on the Building or any portion of it (other than depreciation on personal property and equipment as described above);

(d) costs, disbursements and other expenses (including permit, license, and inspection fees) incurred for leasing, renovating, decorating or redecorating, painting or improving space for tenants or potential tenants of the Building;

(e) Landlord’s cost of electricity or any other service sold to tenants for which Landlord is to be reimbursed as a charge over the rent payable under the lease with that specific tenant;

(f) principal or interest payments on loans secured by mortgages or deeds of trust on the Building or lease rentals paid or payable on any ground or underlying lease;

(g) financing or refinancing costs and mortgage interest and mortgage amortization payments, all penalties, fines and damages payable under any mortgage or deed of trust and legal and other professional fees incurred in connection with such financing or refinancing;

(h) costs incurred with respect to a sale of all or any portion of the Building or the land or the Property or any interest therein or of any interest in Landlord or any entity comprising Landlord;

(i) all expenses for which Landlord has received any reimbursement to the extent of such reimbursement, other than indirect reimbursement by the payment of any tenant of Base Rent or its share of Common Area Expenses, or for which Tenant has paid to third parties or items or services that Landlord provides selectively to one or more tenants of the Building other than Tenant;

(j) repairs or other work needed because of fire, windstorm, or other casualty or cause insured against by Landlord to the extent Landlord’s insurance provides insurance coverage, or any other costs recoverable by Landlord under its insurance, excluding the cost of deductibles paid by Landlord for insurance;

(k) expenses (including, without limitation, leasing commissions, rents payable for a leasing office, architectural, space planning or engineering services) incurred in leasing or procuring tenants;

(l) to the extent any cost is includable in Common Area Expenses and incurred with respect to both the Building and other properties (including, without limitation, salaries, fringe benefits and other compensation of Landlord’s personnel who provide services to both the Building and other properties), there shall be excluded from Common Area Expenses a fair and reasonable percentage thereof which is properly allocable to such other properties;

(m) the cost of the acquisition of the Property or the construction of improvements to the Building in connection with an expansion thereof;

(n) professional fees (including legal and accounting fees) not allocated to the operation or management of the Property and professional fees (including legal and accounting fees) allocable to disputes with, or preparation of leases for, tenants and prospective tenants or in enforcing any lease or in renewing, extending or amending any lease for a tenant in the Building;

(o) Any penalty charges incurred by Landlord due to the violation of any law unless such charges result from the violation of law by any tenant or such tenant’s failure to pay for the same, which shall be paid for and billed directly to such tenant;

(p) cost of repairs or other work occasioned by the exercise of the right of eminent domain;

(q) Advertising and promotional expenditures;

(r) federal, state, or local income taxes, franchise, gift, transfer, excise, capital stock, estate, succession, or inheritance taxes, and penalties or interest for late payment of Taxes (as hereinafter defined);

(s) costs incurred because Landlord or another tenant violated the terms of any lease;

(t) overhead and pro fit paid to subsidiaries or affiliates of Landlord for management or other services on or to the Property or for supplies or other materials, to the extent that the costs of the services, supplies, or materials were higher than the cost thereof if they had not been provided by a subsidiary or affiliate;

(u) fines or penalties incurred because Landlord violated any governmental rule or authority due to Landlord’s actions or omissions;

(v) costs or expenses of a partnership, or other entity, which constitutes Landlord not directly related to the Property (such as accounting fees, tax returns and income taxes of such entity), expenses incurred by Landlord not directly related to the land, the Property, the Building and/or its operations including, without limitation, compensation paid to officers, executives, or partners of Landlord; nor

(w) other expenses that under generally accepted accounting principles consistently applied would not be considered normal maintenance, repair, management, or operation expenses.

Tenant may review Landlord’s records of Tenant’s Share of Common Area Expenses, at Tenant’s sole cost and expense, upon reasonable prior notice at the place Landlord normally maintains such records during Landlord’s normal business hours. Tenant shall have a qualified CPA, unrelated to Tenant or Tenant’s business, which CPA shall not be paid on a contingency basis, perform the audit. If the audit reveals that Tenant’s actual payments for Common Area Expenses exceed Tenant’s Share of Common Area Expenses, Landlord shall apply any overpayment to the next payment of Common Area Expenses due. In the event that the audit reveals that Tenant’s actual payments for Common Area Expenses are less than Tenant’s Share of Common Area Expenses, Tenant shall pay Landlord the deficiency within ten (10) days,

3.5 Taxes . The term “Taxes” shall include, for any calendar year or applicable tax year or period, the total amount incurred or accrued during such calendar year or tax year or period for that portion of the following items that is allocable to that taxable parcel of property of which the Premises is a part (“Tenant’s Tax Parcel”): all ad valorem real property taxes and assessments, special or otherwise, fees or other charges levied upon or with

respect to Tenant’s Tax Parcel, and the rents and additional charges payable by tenants of Tenant’s Tax Parcel, and imposed by any city, county, special/metropolitan district or other taxing authority having jurisdiction, including, but not limited to the Arista Metropolitan District, the Arista Local Improvement District and the Broomfield Urban Renewal Authority; all taxes, levies, fees and charges which may be assessed, levied or imposed in replacement of, or in addition to, all or any part of ad valorem real property taxes or assessments as revenue sources, and which in whole or in part are measured or calculated by or based upon Tenant’s Tax Parcel (including the Common Areas), the leasehold estate of the owners or tenants of Tenant’s Tax Parcel, or the rents and other charges payable by such tenants; capital and place-of-business taxes, and other similar taxes assessed relating to the Common Areas; and any reasonable expenses incurred by Landlord or the other owners of retail premises within Tenant’s Tax Parcel in attempting to reduce or avoid an increase in Taxes, including, without limitation, reasonable legal fees and costs. Notwithstanding anything in this Lease to the contrary, Taxes will not include the following (the “Excluded Taxes”): (i) any (a) taxes on Landlord’s income, or profit or corporate taxes, (b) franchise taxes, (c) estate, inheritance, succession, capital stock, mortgage recording, gains, transfer or gift taxes, or (d) similar taxes imposed on Landlord; (ii) any ad valorem real property taxes and assessments levied upon or with respect to any separately assessed premises; and (iii) any interest or penalties incurred as a result of Landlord’s late payment of Taxes, excepting if such interest or penalty, if any, is due to the actions of Tenant,

3.6 Landlord’s Insurance Costs . The term “Insurance Costs” shall include the costs of all policies of insurance carried by Landlord in accordance with Article 10.

3.7 Other Taxes . As Additional Rent, Tenant shall reimburse Landlord upon demand for any and all taxes payable by Landlord (other than the Excluded Taxes), whether or not now customary or within the contemplation of Landlord and Tenant, within thirty (30) days after receipt of written demand therefore:

(a) upon, measured or reasonably attributable to the cost or value of Tenant’s equipment, furniture, fixtures and other personal property located in the Premises or Alterations (defined in Section 6.1), made in or to the Premises by or for Tenant, regardless of whether title to such improvements is in Tenant or Landlord;

(b) upon or measured by Rent, including without limitation, any gross income tax or excise tax levied by the federal government or any other governmental body with respect to the receipt of Rent;

(c) upon or with respect to the possession, leasing, operating, management, maintenance, alteration, repair, use or occupancy by Tenant of the Premises or any portion of the Premises; and

(d) upon this transaction or any document to which Tenant is a party creating or transferring an interest or an estate in the Premises.

Tenant shall pay promptly when due all sales, merchandise and personal property taxes on Tenant’s personal property in the Premises and any other taxes payable by Tenant, the non-payment of which might give rise to a lien on the Premises or Tenant’s interest in the Premises.

3.8 Security Deposit . On or before the Commencement Date, Tenant shall deposit with Landlord the Security Deposit. The Security Deposit shall be held by Landlord as security for the timely and faithful performance by Tenant of all the terms, covenants, and conditions of this Lease to be kept and performed by Tenant during the Term. If Tenant defaults with respect to any provision of this Lease, including, but not limited to, the provisions relating to the payment of Base Rent, Tenant’s Share of Common Area Expenses or any other Rent, Landlord may (but shall not be required to) use, apply or retain all or any part of the Security Deposit for payment of Base Rent, Tenant’s Share of Common Area Expenses or any other Rent due, or for the payment of any amount which Landlord may spend or become obligated to spend by reason of Tenant’s default, or to compensate Landlord for any other loss or damage, including reasonable attorneys’ fees, which Landlord may suffer by reason of Tenant’s default. If any portion of the Security Deposit is so used or applied, Tenant shall, within five (5) days after receipt of written demand therefor, deposit cash with Landlord in an amount sufficient to restore the Security Deposit to its original amount, and Tenant’s failure to do so shall be an Event of Default under this Lease. Landlord shall not be required to keep the Security Deposit separate from its general funds, and Tenant shall not he entitled to interest on the Security Deposit. If Tenant shall fully and faithfully perform every provision of this Lease to be performed by it, the Security Deposit or any balance thereof shall be returned to Tenant (or, at Landlord’s option, to the last assignee of Tenant’s

interest hereunder) within thirty (30) days following expiration of the Term and Tenant’s vacation of the Premises in accordance with Section 20.1, less any amount reasonably withheld by Landlord for repairs under this Lease, which repairs shall not include ordinary wear and tear.

ARTICLE 4

Parking

4.1 Subject to applicable codes and ordinances, and any recorded documents now or hereafter affecting the Building, Tenant shall be entitled to the non-exclusive and non-reserved use of 4 parking spaces per 1,000 square feet of rentable area in the Premises in the Grand Parkade (the “Tenant’s Parking Ratio”) during the hours of 6:00 am to 6:00 pm Monday through Friday (the “Guaranteed Parking Hours”); provided , however , that Landlord shall have the right to temporarily curtail Tenant’s Parking Ratio during Guaranteed Parking Hours solely in the event that Landlord requires the use of such parking spaces in connection with its development of the Building provided that Landlord shall work with Tenant to make reasonable accommodations for Tenant’s parking needs during such development. In addition to Tenant’s rights to Tenant’s Parking Radio during Guaranteed Parking Hours, Tenant shall also be entitled to: (i) Tenant’s Parking Ratio during such times other than Guaranteed Parking Hours so long as the parking spaces used by Tenant are occupied on or prior to 6:00 pm on Monday through Friday and then during such time as such parking spaces remain occupied, and (ii) such parking spaces as may be available during such times other than Guaranteed Parking Hours. Tenant’s use of parking in the Property shall at all times be at no cost to Tenant.

ARTICLE 5

Signage

5.1 Signs . Tenant shall have the right to signage on the lobby directory at Landlord’s cost and on the main entry door to the Premises and on the Building at Tenant’s cost, subject to Landlord’s standards and approval as to the design, location, size, color and type of all such signage (which approval by Landlord shall not be unreasonably withheld, conditioned or delayed), and subject to Tenant receiving all necessary and required approvals from any relevant governmental authority or governing body. All signage shall be installed and maintained at Tenant’s sole expense in accordance with the plans submitted to and approved by Landlord (which approval by Landlord shall not be unreasonably withheld, conditioned or delayed) and all Applicable Laws.

ARTICLE 6

Alteration, Care, Repair and Liens

6.1 Alterations, Additions and Improvements . Tenant shall not make or allow to be made any alteration, addition or improvement in or to the Premises (“Alterations”, and each an “Alteration”) without the prior written consent of Landlord, which consent shall not be unreasonably withheld, conditioned or delayed if such Alterations do not affect the structural, exterior, mechanical, electrical or plumbing components of the Building or Premises, except that Landlord’s consent shall not be required for any: (i) purely decorative alterations such as painting, plastering, carpeting and similar decorative items; (ii) nonstructural interior alterations costing, for each respective project, Fifty Thousand Dollars ($50,000.00) or less; and (iii) the Tenant Improvements and other initial alterations in connection with Tenant’s initial occupancy of the Premises. Landlord’s consent to any Alteration requiring Landlord’s consent or Landlord’s approval of any plans or specifications therefor will not create any responsibility or liability on the part of Landlord for the completeness, design sufficiency or compliance with any Applicable Laws, rules or regulations of governmental agencies or authorities of such Alteration, plans or specifications. In the event Landlord consents to the making of any Alteration, such Alteration shall be made by Tenant at Tenant’s sole cost and expense. Landlord may impose, as a condition to granting such approval, reasonable requirements, including without limitation, requiring that plans and specifications be submitted for Landlord’s approval, which approval shall not be unreasonably withheld, conditioned or delayed, that reasonable insurance in light of the proposed Alteration be maintained by Tenant, and that construction be accomplished during a reasonable specified time period. All Alterations shall be done in accordance with all Applicable Laws, regulations, ordinances; and rules of all governmental or other authorities. In undertaking any Alteration, Tenant shall not make or permit any defacement, injury or waste in, to or about the Premises or any part of the Building. Any Alterations, including, but not limited to, wall coverings, paneling and built-in shelving or cabinet work, but excepting movable furniture and trade fixtures, shall, at the option of Landlord, become a part of the Premises and Landlord’s property and shall

be surrendered with the Premises. Notwithstanding the foregoing, upon the expiration or sooner termination of the Term, Tenant shall at Tenant’s sole cost and expense, forthwith and with all due diligence, remove any Alterations made by Tenant and designated by Landlord in writing to Tenant at the time of approval by Landlord of such Alterations that same must be so removed. Tenant shall repair any damage to the Premises caused by such removal and restore the Premises to their condition at the commencement of this Lease, ordinary wear and tear and damage by casualty excluded.

6.2 Tenant’s Care and Repair . Except for those items expressly required to be maintained and repaired by Landlord pursuant to Section 8.3, Tenant will maintain and repair the Premises (including, without limitation, Tenant’s equipment, personal property and trade fixtures located in the Premises, and all mechanical, plumbing and electrical equipment after the point of connection to the Premises and which exclusively serve the Premises), in good working order and in good, clean and sanitary condition, reasonable wear and tear and damage by casualty excluded. Tenant will immediately advise Landlord of any damage to the Premises or the Building. At Landlord’s option, and subject to the provisions of Section 10.6 below, all damage or injury to the Premises or the Building, or the fixtures, appurtenances and equipment in the Premises or Building which is caused by Tenant, its agents, employees, or invitees, may be repaired, restored or replaced by Landlord, and Tenant shall be responsible for Landlord’s out-of-pocket expenses incurred by Landlord, plus five (5%) percent thereof on account of Landlord’s overhead and related expenses, which will be collectible as Rent and will be paid by Tenant within ten (10) days after delivery of a statement for such expense along with documentary evidence reasonably acceptable to Tenant of such expenses. All repairs made by Tenant shall be made using contractors approved by Landlord, which approval shall not be unreasonably withheld, conditioned or delayed.

6.3 Mechanic’s Liens . Tenant agrees to pay when due all sums of money that may become due for, or purporting to be due for, any labor, services, materials, supplies or equipment alleged to have been furnished or to be furnished to or for Tenant in, upon or about the Premises and/or Landlord’s interest therein.

If any mechanic’s lien shall be filed or threatened against the Premises, the Property or the Building based upon any act of Tenant or anyone claiming by, through or under Tenant, Tenant, after notice thereof from Landlord, promptly shall commence such action by bonding over, payment or otherwise, as will remove or satisfy such lien within thirty (30) days. In the event Tenant does not remove or satisfy said lien within said thirty (30) day period, Landlord shall have the right to do so by posting a bond or undertaking and Tenant agrees to reimburse Landlord for any and all expenses incurred by Landlord in connection therewith within ten (10) days after receipt by Tenant of Landlord’s invoice therefor. These expenses include, but are not limited to, filing fees, legal fees and bond premiums.

In addition to any other requirements set forth in this Lease, prior to the commencement of any construction or the furnishing of any materials within the Premises by or at the direction of Tenant, Tenant shall post and keep posted in a conspicuous place upon the Premises a notice pursuant to Colorado Revised Statutes § 38-22-105 (as amended) and any appropriate notice wider any similar law or regulation, notifying all laborers and materialmen providing labor or materials to the Premises that the Premises, Building, and Landlord’s interest therein are not subject to any lien for the same.

However, nothing in this Section 6.3 shall he deemed or construed as (a) Landlord’s consent to any person, firm or corporation for the performance of any work or services or the supply of any materials to the Premises, or (b) giving Tenant or any other person, firm or corporation any right to contract for or to perform or supply any work, services or materials that would permit or give rise to a lien against the Premises or the Building.

ARTICLE 7

Use of Premises

7.1 General . The Premises will be used only for the Permitted Use and for no other purpose. In addition, Tenant will not: (i) do or permit to be done in or about the Premises, nor bring to, keep or permit to be brought or kept in the Premises, anything which is prohibited by or will in any way conflict with any law, statute, ordinance or governmental rule or regulation which is now in force or which may be enacted or promulgated after the date of this Lease; (ii) permit anything to be done in or about the Premises which will in any way obstruct or interfere with the rights of other occupants or users of the Building, or injure or unreasonably annoy them; (iii) use or allow the Premises to be used for any improper, immoral, unlawful or objectionable purpose; or (iv) cause, maintain or permit any nuisance in, on or about the Premises or commit or allow to be committed any waste in, on or about the Premises.

7.2 Applicable Laws . “Applicable Laws” shall mean all laws, statutes, ordinances, and governmental rules, regulations or requirements now in force or in force after the date of this Lease, the governing documents, rules, regulations or requirements of any governing association, whether now in force or in force after the date of this Lease, the requirements of any board of fire underwriters or other similar body constituted on or after the date of this Lease, any direction or permanent occupancy certificate issued pursuant to any law by any public officer or officers, as well as the provisions of all recorded documents affecting the Premises. At its sole cost and expense, Tenant will promptly comply with all Applicable Laws insofar as they relate to (i) Tenant’s use, occupancy or alteration of the Premises, (ii) the condition of the Premises resulting from Tenant’s use, occupancy or alteration of the Premises, or (iii) alterations to the Premises required as a result of Tenant’s status under Applicable Laws. Tenant will not be required to perform structural changes or changes outside the Premises required by Applicable Laws unless such requirement arises by virtue of (a) Tenant’s use or occupancy of the Premises, or (b) improvements or alterations made by or for Tenant.

7.3 Operation of Tenant’s Business . Tenant hereby acknowledges that it has investigated whether its proposed use of the Premises and its proposed manner of operation will comply with all Applicable Laws, and Tenant assumes the risk that its proposed use of the Premises and its proposed manner of operation are, and will continue to be, in compliance with all Applicable Laws, including, without limitation, all zoning laws regulating the use and enjoyment of the Premises. Tenant hereby waives any defense to its obligations hereunder based upon the legal doctrines of frustration, impossibility or other defenses based on its inability to use the Premises for the purposes for which they are leased hereunder. Tenant acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty as to the suitability of the Premises to the conduct of Tenant’s business.

7.4 Hazardous Materials . As used in this Section 7.4, the term “Hazardous Materials” shall mean any hazardous or toxic substances, materials or wastes which are regulated, or become regulated, by the United States Government or by any State of Colorado, local, or other governmental authority. Tenant shall not store, use or dispose of any Hazardous Materials in, on or about the Premises or any portion of the Building in violation of applicable laws. Tenant will be solely responsible for and will defend, indemnify and hold Landlord, its agents and employees harmless from and against all claims, costs and liabilities, including attorneys’ fees, court costs. and other expenses of litigation (i) arising out of or in connection with Tenant’s breach of its obligations contained in this Section 7.4, or (ii) arising out of or in connection with the removal, clean-up and restoration work and materials required under applicable law to return the Premises or any portion of the Building to the condition existing prior to the appearance of Hazardous Materials stored, used or disposed in or about the Premises by Tenant in violation of applicable laws. Without limiting the foregoing, if Tenant is not in compliance with this Section 7.4 after ten (10) days after receipt by Tenant of written notice from Landlord of Tenant’s breach of this Section 7.4, Landlord shall have the right, but not the obligation, to enter upon the Premises and take whatever actions are reasonably necessary to effectuate compliance including, but not limited to, the removal of any such Hazardous Materials. Tenant’s obligations under this Section 7.4 will survive the expiration or other termination of this Lease.

7.5 Rules and Regulations . The Tenant agrees to comply with the rules and regulations set forth in Exhibit E and with such reasonable modifications thereof and additions thereto as the Landlord may hereafter from time to time make for the Building. The Landlord shall not be responsible for the non observance by any other tenant of any said rules and regulations.

ARTICLE 8

Common Areas and Services

8.1 Definition . The term “Common Areas” is defined to mean all areas and facilities within or adjoining the Building that are provided and designated from time to time by Landlord for the general, nonexclusive use and convenience of all tenants of the Building and their respective employees, invitees, licensees and other visitors, including, without limitation, alleyways, lobbies, hallways, entry ways, loading areas, toilet facilities, elevator facilities, shafts, driveways, parking areas, mechanical and electrical rooms, janitors’ and storage closets, stairways, lighting facilities, trash facilities, utility lines, sidewalks, covered walkways, terraces, loading areas, underground walkways, plazas, courts, retaining walls, access drives, truck serviceways and landscaped areas.

8.2 Right of Use . Landlord grants Tenant, its employees, invitees, customers, licensees and other visitors a nonexclusive license for the Term to use the Common Areas, subject to the terms and conditions of this Lease. Without advance notice to Tenant (except with respect to matters covered by subsection (a) below) and without any liability to Tenant in any respect, Landlord will have the right to:

(a) establish and enforce reasonable rules and regulations concerning the maintenance, management, use and operation of the Common Areas;

(b) close off any of the Common Areas to whatever extent required in the opinion of Landlord and its counsel to prevent a dedication of any of the Common Areas or the accrual of any rights by any person or the public to the Common Areas, provided such closure does not deprive Tenant of the beneficial use, access to or enjoyment of the Premises in any material respect;

(c) temporarily close any of the Common Areas for maintenance, alteration or improvement purposes, provided such closure does not deprive Tenant of the beneficial use, access to or enjoyment of the Premises in any material respect;

(d) change the size, use, shape or nature of any such Common Areas, or change the arrangement and/or location of or regulate or eliminate the use of any concourse, or any elevators, stairs, toilets or other public conveniences in the Common Areas, provided such changes does not deprive Tenant of the beneficial use, access to or enjoyment of the Premises in any material respect;

(e) expand the Building or convert any portion of the Building (excluding the Premises) to Common Areas, provided such expansion or conversion does not deprive Tenant of the beneficial use, access to or enjoyment of the Premises in any material respect, In the event of any such changes in the Building, Landlord may make an appropriate adjustment in Tenant’s Share;

(f) limit or prohibit Tenant’s access to certain Common Areas, such as, by way of example but not limitation, the roof, access shafts, storage closets, janitor closets, and other areas necessary for Building operations, but not generally open to tenants, provided such limited or prohibited’ access does not deprive Tenant of the beneficial use, access to or enjoyment of the Premises in any material respect.

8.3 Landlord’s Maintenance and Services .

(a) Repair and Maintenance . Landlord will maintain, repair and restore or cause to be maintained, repaired and restored the Common Areas, including, but not limited to lobbies, elevator(s), stairs, roof, walkways, driveways and restrooms, if any; the mechanical, plumbing and electrical equipment serving the Building and the Premises; and the structural components of the Building, in reasonably good order and condition; provided , however , that such obligations shall be subject to the provisions of Article 11 and Article 12.

(b) Services . Landlord will keep or cause to be kept the Common Areas in clean and orderly condition, free of debris and properly lighted and landscaped. Landlord will also provide or cause to be provided electricity, heating, ventilation and air-conditioning (as required by the seasons), lighting, restroom supplies, window washing and janitorial services to the Premises and to the interior Common Areas sufficient for their normal use. Landlord will not be in default under this Lease or be liable for any damages directly or indirectly resulting from, nor will the Rent be abated by reason of the following (each, an “Interruption”) (a) the installation, use or interruption of use of any equipment in connection with the furnishing of any of such services, (b) the failure to furnish, or delay in furnishing, any such services when such failure or delay is caused by accident or any condition beyond the reasonable control of Landlord or by the making of necessary repairs or improvements to any portion of the Building, (c) any limitation, rationing or restrictions on use of water, electricity, gas or any other form of energy serving the Building; (d) the completion of construction surrounding the Building, including construction of parks, adjacent buildings or improvements relating to either, or (e) any interruption in access to the Common Areas caused by any activities conducted by or at the direction of governmental or quasi-governmental authorities within the public right-of-ways or alley adjacent to the Land; provided , however , if such Interruption is caused by or due to the gross negligence or willful acts or omissions of Landlord, its agents, servants or employees, contractors, or

Landlord’s default under this Lease, then, and without being obligated or waiving Landlord’s default, Tenant shall have the right to do any or all of the following: (i) abate all Base Rent and Additional Rent from the date of such Interruption; (ii) if such Interruption is not resolved within seven (7) days, take all actions to resolve such Interruption and in such case, Landlord shall reimburse Tenant the amounts incurred by Tenant in resolving such Interruption within thirty (30) days after delivery to Landlord of any invoices or expenses from Tenant and if Landlord shall fail to reimburse Tenant, then Tenant may offset the reimbursements due Tenant against any payment becoming due under this Lease or any other payment obligations under this Lease (provided nothing herein shall limit any other rights and remedies available to Tenant at law, in equity, and/or under this Lease); and/or (iii) if such Interruption is not resolved within thirty (30) days, then Tenant may elect to terminate this Lease by providing Landlord with written notice and this Lease shall terminate effective as of the date of such notice.

(c) Limitation on Liability . Landlord will not be liable to Tenant or any other person, for direct or consequential damages, or otherwise, for any failure to supply any heat, air conditioning, elevator, cleaning, lighting, or other service which Landlord has agreed to supply during any period when Landlord uses reasonable diligence to supply such services; provided , however , if such service is caused by or due to the gross negligence or willful acts or omissions of Landlord, its agents, servants or employees, contractors, or Landlord’s default under this Lease, then, in addition to any remedies available by law, and without being obligated or waiving Landlord’s default, Tenant shall have the cumulative right to do any or all of the following: (i) abate all Base Rent and Additional Rent from the date of such service interruption; (ii) if such service interruption is not resolved within seven (7) days, take all actions to resolve such service interruption and in such case, Landlord shall reimburse Tenant the amounts incurred by Tenant in resolving such service interruption within thirty (30) days after delivery to Landlord of any invoices or expenses from Tenant and if Landlord shall fail to reimburse Tenant, then Tenant may offset the reimbursements due Tenant against any payment becoming due under this Lease or any other payment obligations under this Lease (provided nothing herein shall limit any other rights and remedies available to Tenant at law, in equity, and/or under this Lease). Landlord shall not be responsible for any electrical current surges, unless any increase is cause by or due to the gross negligence or willful acts or omissions of Landlord, its agents, servants or employees, contractors, or Landlord’s default under this Lease. Landlord reserves the right temporarily to discontinue such utilities and services, or any of them, at such times as may be necessary by reason of accident, repairs, alterations or improvements, strikes, lockouts, riots, acts of God, governmental preemption in connection with a national or local emergency, any law, rule, order or regulation of any governmental agency, conditions of supply and demand which make any product unavailable, Landlord’s compliance with any mandatory governmental energy conservation or environmental protection program, or any voluntary governmental energy conservation program at the request of or with consent or acquiescence of Tenant, or any other happening beyond the control of Landlord. Landlord will not be liable to Tenant or any other person or entity for direct or consequential damages resulting from the admission to or exclusion from the Building or Common Areas of any person. Landlord will not he liable for damages for injury to persons or property or interruption of business for any discontinuance permitted under this Section 8.3(c), nor will such discontinuance in any way be construed as an eviction of Tenant, cause an abatement of Rent, or operate to release Tenant from any of Tenant’s obligations under this Lease, unless such injury, interruption of business or discontinuance of services is caused by or due to the gross negligence or willful acts or omissions of Landlord, its agents, servants or employees, contractors, or Landlord’s default under this Lease.

8.4 Reimbursement of Certain Costs . Any improvements or alterations which are made to the Building by Landlord shall be included in Common Area Expenses for the purposes of this Lease it (a) made for the purpose of reducing the costs and expenses incurred by Landlord in managing, maintaining, operating and insuring the Building, including the Common Areas, and actually reduce such costs and expenses incurred by Landlord, and then only the extent that such savings can be amortized over the original Term or (b) after the Commencement Date, same are required pursuant to any governmental law or regulation that was not applicable to the Building or the subject portion of it as of the Commencement Date and which are not a result of the nature of Tenant’s use of the Premises.

ARTICLE 9

Indemnity and Waiver

9.1 Indemnification by Tenant . Subject to Section 9.2 and Section 10.6, Tenant shall indemnify and hold Landlord harmless against and from any and all claims, demands, liabilities, actions and damages, and all costs and expenses related thereto (including reasonable attorneys’ fees, court costs and other expenses of litigation) and

all damages and liabilities of any kind or nature whatsoever, attributable to (a) the injury, death, disability or illness of any person or persons, or damage to any property occurring in, on or about the Premises or arising from Tenant’s use of the Premises or from the conduct of its business or from any activity, work, or other things done, permitted or suffered by Tenant in or about the Premises; (h) any breach or default (after applicable notice and cure period) in the performance of any of Tenant’s obligations under this Lease; or (c) any gross negligence or intentionally wrongful conduct of Tenant. In any such action or proceeding against Landlord by reason of any such claim, if Landlord elects, Tenant upon notice from Landlord shall defend the same at Tenant’s expense by counsel reasonably satisfactory to Landlord. Tenant shall give prompt notice to Landlord in case of casualty or accidents in the Premises.

9.2 Indemnification by Landlord . Subject to Section 9.1 and Section 10.6, Landlord shall indemnify and hold Tenant harmless against and from any and all claims, demands, liabilities, actions and damages, and all costs and expenses related thereto (including reasonable attorneys’ fees, court costs and other expenses of litigation) and all damages and liabilities of any kind or nature whatsoever, attributable to (a) the injury, death, disability or illness of any person or persons, or damage to any property occurring in, on or about the Common Areas, or (b) Landlord’s gross negligence or intentionally wrongful conduct.

9.3 Waiver; Assumption of Risk . Tenant, as a material part of the consideration to Landlord, hereby assumes all risk of damage to property or injury to persons in, upon or about the Premises, from any cause other than the gross negligence or intentionally wrongful conduct or omission of Landlord or Landlord’s agents, servants or employees, contractors; Tenant hereby waives and releases all claims in respect thereof against Landlord. Landlord or its agents shall not be liable for any loss or damage to persons or property resulting from fire, explosion, sewer stoppage or leakage, falling plaster, steam, gas, electricity, snow, ice, water or rain which may leak from any part of the Building or from the pipes, appliances or plumbing works therein or from the roof, street or subsurface or from any other place or resulting from dampness, or any such injury or damage from any other cause whatsoever, unless caused by or due to the gross negligence or intentionally wrongful conduct or omission of Landlord or Landlord’s agents, servants or employees, or contractors. Landlord and its agents and employees shall not be liable for interference with light, view or air or for any latent defect in the Premises, unless caused by or due to the gross negligence or intentionally wrongful conduct or omission of Landlord or Landlord’s agents, servants or employees, or contractors. Landlord shall have no obligation to provide security guards, patrols, devices, or systems for the Premises or the Building and shall not be liable for any failure to provide such security services. Landlord shall not be responsible to Tenant for any loss or theft of property in or from the Premises, or for any loss or theft or damage of or to any property left with an employee of Landlord, however occurring, unless caused by or due to the gross negligence or intentionally wrongful conduct or omission of Landlord or Landlord’s agents, servants or employees, contractors, licensees or invitees.

ARTICLE 10

Insurance

10.1 Liability Insurance . At all times during the term of this Lease, Tenant shall, at its sole cost and expense, for the mutual benefit of Landlord and Tenant, maintain personal injury and property damage commercial liability insurance against claims for bodily injury, death or property damage occurring on, in or about the Premises during the term of this Lease of not less than $1,000,000.00 per occurrence, $2,000,000.00 aggregate with respect to bodily injury, death or property damage and including contractual indemnity coverage. In the event that Tenant shall not have delivered to Landlord a policy or certificate evidencing such insurance fifteen (15) days prior to the Commencement Date and five (5) days prior to the expiration dates of each expiring policy, Landlord may obtain such insurance as it may reasonably require to protect its interest. The cost of such policies shall be paid by Tenant to Landlord as Additional Rent upon demand.

10.2 Workers’ Compensation . During the Term, Tenant shall maintain workers’ compensation insurance and employer’s liability insurance. Workers’ compensation shall be in statutory limits, and state disability insurance shall be as required by applicable law, covering all employees in not less than the statutory requirements.

10.3 All Risks and Difference in Conditions Insurance . At all times during the term of this Lease, Landlord shall keep or cause to be kept the Property insured for the benefit of Landlord against loss or damage by risks now or hereafter embraced by “All Risks,” “Difference in Conditions,” and loss of rent coverages, and against such other risks as Landlord from time to time reasonably may designate in amounts sufficient to prevent Landlord from becoming a coinsurer, or as may be required by any lender.

In any event, the amount applicable to “All Risks” coverage maintained by Landlord under this Section 10.3 shall be at least ninety percent (90%) of the then full replacement cost of the insured portions of the Property. Such fall replacement cost shall be determined from time to time (but not more frequently than once in any 12 calendar months) by an appraiser, architect or other person or firm designated by Landlord.

The parties agree that Landlord shall not provide any insurance coverage for Tenant’s merchandise, trade fixtures, furnishings, equipment and other personal property of Tenant. Tenant shall carry and maintain, or cause to be carried and maintained, at all times during the Term of this Lease and at Tenant’s expense such other insurance or such additional amounts of insurance with respect to the Premises as is generally maintained by persons having similar exposures or properties similarly situated.

10.4 Insurance on Common Areas . At all times during the term of this Lease, Landlord shall keep or cause to be kept the Common Areas insured for bodily injury and property damage liability, “All Risk” property coverage, “Difference in Conditions,” workers’ compensation, employee’s liability and any other casualty or risk insurance which Landlord or Landlord’s insurance carrier deems necessary or appropriate.

10.5 Increase in Property Insurance Premium . Tenant covenants and agrees to promptly pay to Landlord as Rent, upon demand, the amount of any increase in the rate of insurance paid by Landlord on the Premises or on any other part of the Building that (but for Tenant’s act(s) or Tenant’s permitting certain activities to take place which result in an increase in said rate of insurance) would otherwise have been in effect.

10.6 Waiver of Claims . Landlord and Tenant hereby waive any and all rights to recover against each other, and against their respective officers, directors, members, managers, stockholders, partners, employees, agents, representatives, customers or business visitors, for damage to such waiving party or loss of its property or the property of others under its control arising from any cause covered by any property insurance required to be carried by such waiving party hereunder or actually carried by or for the benefit of such waiving party, to the extent of the limits of such property insurance. In addition, all property insurance policies maintained by Landlord and Tenant shall expressly permit the foregoing waiver and shall contain provisions waiving the insurer’s claims or rights of subrogation against the other party hereto for loss or damage to the property so insured. Each party hereto hereby waives on behalf of the insurers of such party’s property any and all claims or rights of subrogation of any such insurer against the other party hereto for loss of or damage to the property so insured, and each party hereby agrees to maintain insurance upon its property.

10.7 Insurer and Policy Requirements . All insurance policies to be maintained by Tenant under this Article 10: (a) shall be issued by companies licensed to do business in the State of Colorado, reasonably acceptable to Landlord, and maintaining a rating of A-/VIII or better in A. M. Best’s Insurance Reports-Property-Casualty (or an equivalent rating in any successor index adopted by Best’s or its successor), (b) shall provide that they may not be canceled or modified unless Landlord and its lender, if applicable, is given at least 30 days’ prior written notice of such cancellation or modification, unless cancelled by non-payment of premium in which case Landlord or its lender shall have ten (10) days’ prior written notice (c) liability policies (except employer’s liability) shall name, as additional insureds, Landlord, the property manager for the Building, and any mortgagee of Landlord whose name and address shall have been furnished to Tenant and (d) all liability insurance required to be maintained by Tenant shall he primary and non-contributory in all respects. All policies maintained by Tenant providing property insurance coverage pursuant to this Article 10 shall name, as loss payees, Landlord, each mortgagee of Landlord described above and Tenant, as their interests may appear and shall contain the waiver of subrogation provisions described in Section 10.6.

ARTICLE 11

Damage by Fire, Theft and Water Damage

11.1 Landlord’s Restoration Obligation . If the Premises are made untenantable in whole or in part by fire or other casualty, the Base Rent and Additional Rent, until repairs shall be made or the Lease terminated as hereinafter provided, shall be abated on a per diem basis in proportion to the part of the Premises which is usable by

Tenant. If such damage shall be so extensive that the Premises cannot be restored by Landlord, in Landlord’s reasonable estimation, within a period of nine (9) months after the occurrence of the casualty or Landlord estimates that the Premises can be restored within such period but such restoration is not completed within such period, then either party shall have the right to terminate this Lease by notice to the other given at any time within thirty (30) days alter the date of Landlord’s determination of how long it will take to repair such damage (which determination shall be made within forty-five (45) days of such casualty) or at such time that it becomes reasonably certain that such restoration will be completed within such nine (9) month period. If the damage to the Premises can be restored by Landlord, in Landlord’s reasonable estimation, within a period of nine (9) months after the occurrence of the casualty, Landlord shall repair the damage. If a portion of the Building owned in fee simple by Landlord other than the Premises shall be so damaged that in the opinion of Landlord such portion should be restored in such a way as to alter the Premises materially, Landlord may terminate this Lease by notice to Tenant given at any time within thirty (30) days after the date of such damage. Notwithstanding the foregoing, Landlord shall not be obligated to repair any damage to the Premises which occurs within the last twelve (12) months of the Term and if Landlord so elects not to repair, Landlord shall terminate this Lease by written notice to Tenant within forty-five (45) days after such casualty. If neither Landlord nor Tenant terminates this Lease as provided in this Section 11.1, then Landlord will repair the Premises. If Landlord or Tenant gives effective termination notice pursuant to this Section 11.1, this Lease and the term and the estate hereby granted shall expire on the date thirty (30) days after the giving of such notice as hilly and completely as if such date were the date hereinbefore set for the expiration of the term of this Lease.

11.2 Abatement of Rent During Period of Restoration . In the event that this Lease shall remain in full force and effect pursuant to the provisions of this Article, the Base Rent shall be reduced or abated, based upon the portion of the Premises that Tenant is unable to use, and does not use, as a result of the casualty, as of the date of the occurrence of such damage or destruction until the completion of Landlord’s restoration.

ARTICLE 12

Eminent Domain

12.1 Eminent Domain . If all or substantially all of the Building or the Premises is taken for any public or quasi-public use under any governmental law, ordinance or regulation or by right of eminent domain or is sold to the condemning authority in lieu of condemnation, then this Lease will terminate as of the date when physical possession of the Building or the Premises is taken by the condemning authority (the “Ending Date”). If less than all or substantially all of the Building or the Premises is thus taken or sold and if, after such partial taking, in Landlord’s reasonable judgment, alteration or reconstruction of the Building is not economically justified, Landlord (whether or not the Premises are affected thereby) may terminate this Lease by giving written notice to Tenant within sixty (60) days after such taking. If over twenty-five percent (25%) of the Premises is thus taken or sold or if access to the Premises is impaired by any taking, then Tenant may terminate this Lease if in Tenant’s reasonable judgment, the Premises cannot be operated by Tenant in an economically viable fashion because of such partial taking or such impairment to access to the Premises. Such termination by Tenant must be exercised by written notice to Landlord given not later than sixty (60) days after Tenant is notified of the taking by or sale to a condemning authority of the Premises. Termination by Landlord or Tenant shall be effective as of the date when physical possession of the applicable portion of the Building or the Premises is taken by the condemning authority. If neither Landlord nor Tenant elects to terminate this Lease upon a partial taking by or sale to a condemning authority of a portion of the Premises, the Base Rent payable under this Lease will be reduced in proportion to the portion of the Premises which was so taken or sold. If this Lease is not terminated upon a partial taking, Landlord will, at Landlord’s sole expense, promptly restore and reconstruct the Building and the Premises to substantially their former condition to the extent practicable. In no event shall Landlord be required to spend any amount for such restoration or reconstruction in excess of the net amount received by Landlord as compensation for the part of the Premises or the Building so taken.

12.2 Landlord Entitled to Award . In the event of any taking, condemnation or sale in lieu thereof, Landlord shall be entitled to conduct all negotiations related thereto and to receive and retain all amounts awarded or paid in connection therewith (including any award or payment for the value of the unexpired term of this Lease). It is understood in the event of the termination of this Lease as aforesaid, Tenant shall have no claim against the Landlord for the value of any unexpired term of this Lease and no right or claim to any part of the award on account thereof and Tenant hereby waives each such claim or right. Tenant shall, however, have the right to claim from the condemning authority all compensation that may be recoverable by Tenant on account of any loss incurred by Tenant, including, but not limited to, loss due to removing Tenant’s merchandise, furniture, trade fixtures, and

equipment or for damage to Tenant’s business, or loss of business; provided , however , that Tenant may claim such damages only if they are awarded separately in the eminent domain proceeding and not as part of Landlord’s damages.

ARTICLE 13

Default and Remedies

13.1 Events of Default .

An “Event of Default” by Tenant under this Lease shall occur under the following circumstances:

(a) Failure to Pay Rent or Other Amounts . If Tenant fails to pay when due Base Rent and Additional Rent, and such failure shall continue for five (5) days after written notice from Landlord to Tenant of such failure, or if Tenant fails to pay when due any other amounts payable by Tenant under the terms of this Lease, and such failure shall continue for thirty (30) (lays after written notice from Landlord to Tenant of such failure, then such failure shall constitute an Event of Default; provided , however , that with respect to Base Rent and Additional Rent, Tenant shall not be entitled to more than one (I) notice of such failure during any Lease Year, nor more than five (5) notices during the Term. If after one (1) such notice is given in any Lease Year or five (5) notices are given during the Term with respect to Base Rent or Additional Rent, and Tenant fails, during such Lease Year or during the Term, as the case may be, to pay any such amounts when due, such failure shall constitute an Event of Default without further notice by Landlord or additional cure period.

(b) Violation of Lease Terms . If Tenant breaches or fails to comply with any provision of this Lease applicable to Tenant, and such breach or failure to comply is not covered by the provisions of Section 13.1(a) or the other provisions of this Section 13,1 and continues for a period of thirty (30) days after notice thereof by Landlord to Tenant, or, if such breach or failure to comply cannot be reasonably cured within such thirty (30) day period, if Tenant shall not in good faith commence to cure such breach or failure to comply within such thirty (30) day period or shall not diligently complete such cure within sixty (60) days after such notice from Landlord, then such breach or failure shall constitute an Event of Default without any further notice from Landlord or additional cure period; provided , however , that if such breach or failure to comply causes or results in (i) a dangerous condition on the Premises or the Building, (ii) any insurance coverage carried by Landlord or Tenant with respect to the Premises or the Building being jeopardized, or (iii) a material disturbance to another tenant of the Building, then an Event of Default shall exist if such breach or failure to comply is not cured as soon as reasonably possible after notice thereof by Landlord to Tenant, and in any event is not cured within thirty (30) days after such notice. For purposes of this Section 13.1(b), financial inability shall not be deemed a reasonable ground for failure to immediately cure any breach of, or failure to comply with, the provisions of this Lease.

(c) Transfer of Interest Without Consent . If Tenant’s interest under this Lease or in the Premises shall be transferred to or pass to or devolve upon any other party in violation of the provisions of Section 14.1, then such event shall constitute an Event of Default without any notice from Landlord or opportunity to cure.

(d) Execution and Attachment Against Tenant . If Tenant’s interest under this Lease or in the Premises shall be taken upon execution or by other process of law directed against Tenant, or shall be subjected to any attachment at the instance of any creditor or claimant against Tenant and such attachment is not discharged or disposed of within thirty (30) days after the levy thereof, then such event shall constitute an Event of Default without any notice from Landlord or additional cure period.

(e) Bankruptcy or Related Proceedings . If Tenant shall file a petition in bankruptcy or insolvency or for reorganization or arrangement under the bankruptcy laws of the United States or under any similar act of any state, or shall voluntarily take advantage of any such law or act by answer or otherwise, or shall be dissolved or shall make an assignment for the benefit of creditors, or if involuntary proceedings under any such bankruptcy or insolvency law or for the dissolution of Tenant shall be instituted against Tenant or a receiver or trustee shall be appointed for the Premises or for all or substantially all of the property of Tenant, and such proceedings shall not be dismissed or such receivership or trusteeship vacated within sixty (60) days after such institution or appointment, then such event shall constitute an Event of Default without any notice from Landlord or additional cure period.

13.2 Landlord’s Remedies . Time is of the essence hereof. Upon the occurrence of any Event of Default, Landlord shall have the right, at Landlord’s election, then or at any time thereafter, to exercise any one or more of the following remedies:

(a) Cure by Landlord . Upon an Event of Default, Landlord may, at Landlord’s option, but without obligation to do so, and without releasing Tenant from any obligations under this Lease, make any payment or take any action as Landlord may deem necessary or desirable. Landlord may do so without demand on, or written notice to, Tenant and without giving Tenant an opportunity to cure such Event of Default. Tenant covenants and agrees to pay to Landlord, within ten (10) days after demand, all out-of-pocket advances, costs and expenses actually incurred by Landlord in connection with the making of any such payment or the taking of any such action, including reasonable attorney’s fees, together with interest at the rate set forth in Section 20.2 from the date of payment of any such advances, costs and expenses by Landlord.

(b) Termination of Lease and Damages . Upon an Event of Default, Landlord may terminate this Lease, effective at such time as may be specified by written notice to Tenant, and demand (and, if such demand is refused, recover) possession of the Premises from Tenant. Tenant shall remain liable to Landlord for all amounts owing as of the date of such termination, plus damages in an amount equal to the Base Rent, Additional Rent and other Rent which would have been owing by Tenant hereunder for the balance of the Term, had this Lease not been terminated, less the net proceeds, if any, of any reletting of the Premises by Landlord subsequent to such termination, after deducting all Landlord’s out-of-pocket expenses actually incurred by Landlord in connection with such recovery of possession or reletting and not reimbursed or passed on to any replacement tenant. All past due amounts shall be immediately due and payable to Landlord. Landlord shall be entitled to collect and receive such damages from Tenant on the clays on which Base Rent, Additional Rent and other Rent would have been payable if this Lease had not been terminated. Alternatively, at the option of Landlord, Landlord shall be entitled to recover forthwith from Tenant, as damages for loss of the bargain and not as a penalty, an aggregate sum which, at the time of such termination of this Lease, represents the present value (as determined by using a discount rate of 8% per annum) of the amount, if any, by which (i) the aggregate of the Base Rent, Additional Rent and all other Rent payable by Tenant hereunder that would have accrued for the balance of the Term, exceeds (ii) the amount, if any, of such Base Rent, Additional Rent and other Rent which Tenant establishes Landlord can reasonably expect to recover by reletting the Premises for the remainder of the Term, taking into consideration loss of rent while finding a new tenant, tenant improvements and rent abatements necessary to secure a new tenant, leasing brokers’ commissions and other costs which Landlord might incur in leasing the Premises to a new tenant, plus any other sum of money and damages owed by Tenant to Landlord for events or actions occurring prior to the date of termination.

(c) Repossession and Reletting . Upon an Event of Default, Landlord may reenter and take possession of the Premises or any part thereof, without demand or notice, and repossess the same and expel Tenant and any party claiming by, through or under Tenant, and remove the effects of both, without being liable for prosecution on account thereof or being deemed guilty of any manner of trespass, and without prejudice to any remedies for arrears of rent or right to bring any proceeding for breach of covenants or conditions. No such reentry or taking possession of the Premises by Landlord shall be construed as an election by Landlord to terminate this Lease unless a written notice of such intention is given to Tenant. No notice from Landlord hereunder or under a forcible entry and detainer statute or similar law shall constitute an election by Landlord to terminate this Lease unless such notice specifically so states. Landlord reserves the right, following any reentry or reletting, to exercise its right to terminate this Lease by giving Tenant such written notice, in which event this Lease will terminate as specified in such notice. Landlord will use reasonable efforts to relet the Premises. Subject to the foregoing, after recovering possession of the Premises, Landlord may, from time to time, but shall not be obligated to, relet the Premises, or any part thereof, for the account of Tenant, for such term or terms and on such conditions and upon such other terms as Landlord, in its discretion, may determine. Landlord may make such repairs, alterations or improvements as may be reasonably appropriate to accomplish such reletting, and Tenant shall reimburse Landlord upon demand for all costs and expenses, including reasonable attorneys’ fees, which Landlord may incur in connection with such reletting to the extent not reimbursed or passed on to any replacement tenant. Landlord may collect and receive the rents for such reletting, but Landlord shall in no way be responsible or liable for any failure to relet the Premises, or any part thereof, or for any failure to collect any rent due upon such reletting, so long as Landlord has used reasonable efforts to relet the Premises. Notwithstanding Landlord’s recovery of possession of the Premises, Tenant shall continue to pay on the dates herein specified, the Base Rent, Additional Rent and other Rent which would be payable hereunder if such repossession had not occurred, less a credit for the net amounts, if any, actually received by Landlord through any reletting of the Premises.

13.3 Landlord’s Bankruptcy Remedies . Nothing contained in this Lease shall limit or prejudice the right of Landlord to prove and obtain as liquidated damages in any bankruptcy, insolvency, receivership, reorganization or dissolution proceeding, an amount equal to the maximum allowable by any statute or rule of law governing such proceeding in effect at the time when such damages are to be proved, whether or not such amount is greater than, equal to or less than the amounts recoverable, either as damages or rent, tinder this Lease.

13.4 Remedies Cumulative . Exercise of any of the remedies of Landlord under this Tease shall not prevent the concurrent or subsequent exercise of any other remedy provided for in this Lease or otherwise available to Landlord at law or in equity.

13.5 Default by Landlord . Landlord shall not be in default unless Landlord fails to perform obligations required of Landlord within a reasonable time, but in no event later than thirty (30) days (or such shorter time as may be expressly stated in this Lease) after written notice by Tenant to Landlord specifying the manner in which Landlord has failed to perform such obligations; provided , however , that if the nature of Landlord’s obligations is such that more than thirty (30) days are required for performance, then Landlord shall not be in default i f Landlord commences performance within such thirty (30) clay period and thereafter diligently prosecutes the same to completion, but in no event shall such additional period be more than sixty (60) days. In no event shall Tenant have the right to terminate this Lease, or have any right to offset against, or any abatement of, any monies owing by Tenant hereunder, as a result of Landlord’s default, unless expressly allowed under the Willis of this Lease. In the event of a default by Landlord, Tenant’s remedies shall be limited to Tenant’s actual damages and/or an injunction but in no event shall Tenant be entitled to any consequential damages, including, without limitation, lost profits.

ARTICLE 14

Mortgages, Assignments, Subleases and Transfers of Tenant’s Interest

14.1 Limitation on Tenant’s Rights . Except as otherwise provided below, during the Term, in each case, without the prior written consent of Landlord first had and received, neither this Lease nor the interest of Tenant in this Lease, or in any sublease, or in any rentals under any sublease shall be sold, assigned, transferred, mortgaged, pledged, hypothecated or otherwise disposed of whether by operation of law or otherwise, nor shall the Premises or any part thereof be sublet without the prior written consent of Landlord, which consent shall not be unreasonably withheld, conditioned or delayed. Any transfer by operation of law or otherwise, of (i) Tenant’s interest in this Lease, (ii) a 50% or greater equity, capital, profits or voting interest in Tenant (whether stock, partnership or membership interest or otherwise, and aggregating the current transfer with previous transfers), or (iii) practical control of Tenant and its affairs, shall be deemed an assignment of this Lease for purposes of this Section 14.1.

If Tenant’s interest in this Lease is assigned, whether or not in violation of the provisions of this Lease, Landlord may collect all rent paid by the assignee; if the Premises or any part thereof are sublet to, or occupied by, or used by, any person other than Tenant, whether or not in violation of this Lease, Landlord, after default by Tenant under this Lease, may collect all rent paid by the subtenant, user or occupant. In either case, Landlord shall apply the net amount collected to the Rent reserved in this Lease, but neither any such assignment, subletting, occupancy, or use, nor any such collection or application shall be deemed a waiver of any term, covenant or condition of this Lease or the acceptance by Landlord of such assignee, subtenant, occupant or user as a tenant.

Notwithstanding anything to the contrary, Tenant agrees not to enter into any agreement to lease or sublease any portion of the Premises to any tenant or other occupant of any portion of the Property without Landlord’s prior written consent, which shall not be unreasonably withheld, conditioned or delayed. Any attempt by Tenant to so lease or sublease any portion of the Premises to any tenant or other occupant of the Property shall be void and of no force or effect and shall, at Landlord’s option, constitute an. Event of Default under the terms of this Lease.

If Tenant should desire to make an assignment of this Lease or a subletting of all or any portion of the Premises, Tenant shall submit to Landlord a written request for Landlord’s consent to such assignment or subletting, which request shall contain or be accompanied by the following information: (i) the name and address of

the proposed assignee or subtenant; (ii) the terms and conditions of the proposed assignment or subletting; (iii) the nature and character of the business of the proposed assignee or subtenant and its proposed use of the Premises or such portion of it; and (iv) banking, financial and other credit information with respect to the proposed assignee or subtenant (plus such additional financial and credit information as Landlord may reasonably request within fifteen (15) days after receipt of Tenant’s request), reasonably sufficient to enable Landlord to determine the financial responsibility of the proposed assignee or subtenant. Landlord shall then have the following options, to be exercised by notice (“Landlord’s Notice”) given to Tenant within thirty (30) days after receipt of Tenant’s request for consent (or thirty (30) days after receipt of additional financial and credit information requested by Landlord, whichever is later):

(a) If Tenant has requested Landlord’s consent to an assignment of the Lease, Landlord may require Tenant to surrender to Landlord the Premises and to accept a termination of this Lease as of a date to be designated by Landlord in the Landlord’s Notice, which date shall not be less than sixty (60) days nor more than one hundred twenty (120) days following the date of Landlord’s Notice, and this Lease shall expire as to the Premises on such date as if that date had been originally fixed as the Termination Date; or

(b) Landlord shall consent to Tenant’s request, provided that no Event of Default is in existence and further provided that the following further conditions shall be fulfilled:

(i) The subletting or assignment shall be to a tenant whose occupancy will be in keeping with the dignity and character of the then use and occupancy of the Building and whose occupancy will not be more objectionable or more hazardous than that of Tenant herein or impose any additional burden upon Landlord in the operation of the Building;

(ii) Tenant shall not receive any money from the assignee or sublessee, whether in the form of monthly rentals, key money, fixture fees or otherwise, in excess of the Rent being paid to Landlord under this Lease. If any such money is paid to Tenant, Tenant shall promptly pay over such amount to Landlord;

(iii) The proposed sublessee or assignee shall be a reputable party whose financial net worth and financial responsibility is, considering the obligations undertaken, reasonably satisfactory to Landlord and, in the event of an assignment or if the proposed sublease is for all or substantially all of the Premises, equal to or greater than that of Tenant; and

(iv) The subletting or assignment shall be expressly subject to all of the obligations of Tenant under this Lease and the further condition that the Lease and Premises shall not be assigned, encumbered, transferred, or subleased, in whole or in part, or any part thereof suffered or permitted by the sublessee or assignee to be used or occupied by others, without the prior written consent of Landlord in each instance.

No consent by Landlord to an assignment of this Lease and no assignment made as hereinafter permitted, shall be effective until (a) there shall have been delivered to Landlord an agreement, in recordable form, executed by Tenant and the proposed assignee, wherein and whereby such assignee assumes due performance of the obligations on Tenant’s part to be performed under this Lease to the end of the term hereof, and (b) the written consent to such assignment of the holder of any fee or leasehold mortgage to which this Lease is then subject shall have been obtained and delivered to Landlord if so required by the terms of such fee or leasehold mortgage. Notwithstanding the assumption by such assignee of due performance, Tenant shall continue to be fully responsible, jointly and severally, for the due performance of Tenant’s obligations hereunder in the same manner and to the same extent as if no such assignment had been made.

Any assignment, mortgage, pledge, sublease or hypothecation of this Lease, or of the interest of Tenant hereunder without full compliance with any and all requirements set forth in this Lease shall be a breach of this Lease and an Event of Default.

14.2 Effect of Landlord’s Consent . Any consent by Landlord to a sale, assignment, sublease, mortgage, pledge, hypothecation, or transfer of this Lease, shall apply only to the specific transaction thereby authorized and shall not relieve Tenant or any assignee or subtenant from the requirement of obtaining prior written consent of Landlord to any further sale, assignment, sublease, mortgage, pledge, hypothecation, or transfer of this Lease.

With respect to any of the consents requested by Tenant under the provisions of this Article 14, whether or not the Landlord shall have consented thereto, Tenant shall pay to the Landlord all reasonable, out-of-pocket counsel fees and other expenses incurred by the Landlord in connection therewith.

14.3 Tenant to Remain Liable . Tenant agrees and acknowledges that each entity comprising the “Tenant” hereunder shall remain primarily liable under this Lease in the event of any assignment or subletting hereunder.

14.4 No Assignment . Notwithstanding anything in this Article 14 or elsewhere in this Lease to the contrary, the following events shall not require the consent of Landlord: (i) a change in ownership of Tenant as a result of a merger, consolidation, reorganization, or joint venture; (ii) the sale, exchange, issuance or other transfer of Tenant’s stock on a national exchange or between Tenant’s parent company, if any, and any subsidiary, affiliate, related entity, or other entity that controls, is controlled by, or is under common control with Tenant or to any entity resulting from merger or consolidation with Tenant; (iii) the assignment of this Lease or sublease of all or any portion of the Premises to Tenant’s parent entity, a wholly-owned subsidiary of Tenant or any other related entity of Tenant (each, a “Tenant Affiliate”), or to any entity which acquires Tenant through merger, consolidation or other corporate action, or to any entity which purchases all or any portion of the assets of Tenant; (iv) a collateral assignment of Tenant’s interest in this Lease to a lender as security for any indebtedness of Tenant to the lender; or (v) the use or occupancy of the Premises or any part thereof by any Tenant Affiliate(s). Landlord shall not delay, alter, or impede any of the foregoing transactions or combinations thereof.

ARTICLE 15

Transfer of Landlord’s Interest

15.1 Subordination, Non-Disturbance and Attornment . This Lease is subject and subordinate to the lien of any ground or underlying lease and to any mortgage or deed of trust, whether a fee or leasehold mortgage or deed of trust, and all terms and provisions thereof, which may now or hereafter affect the Premises or the Building and to all renewals, modifications, consolidations, replacements and extensions thereof, and advances thereunder (each an “Encumbrance”); provided , however , that the foregoing provision shall only be applicable with respect to those mortgages or deeds of trust or ground or underlying leases for which Tenant has been provided a subordination, non-Disturbance and attornment agreement which is reasonably acceptable, in form and substance, to Tenant and to such mortgagee, trustee, or ground or underlying lessor.

15.2 Financing Modifications . If, in connection with obtaining temporary, construction or permanent financing for the Building or the Land, any lender shall request reasonable modifications of this Lease as a condition to such financing, Tenant agrees that Tenant shall not unreasonably withhold, delay or defer the execution of an agreement of modification of this Lease, provided such modifications are reasonably acceptable to Tenant and do not increase the financial obligations of Tenant hereunder or materially or adversely affect the leasehold interest hereby created or Tenant’s reasonable use and enjoyment of the Premises.

15.3 Sale, Conveyance and Assignment . Subject only to Tenant’s rights under this Lease, nothing in this Lease will restrict Landlord’s right to sell, convey, assign or otherwise deal with the Building or Landlord’s interest under this Lease. .A sale, conveyance or assignment of the portion of the Building including the Premises will automatically release Landlord from liability under this Lease from and after the effective date of the transfer, except for any liability relating to the period prior to such effective date; Tenant will look solely to Landlord’s transferee for performance of Landlord’s obligations relating to the period after such effective date. This Lease will not be affected by any such sale, conveyance or assignment, and Tenant will attorn to Landlord’s transferee.

ARTICLE 16

Entry to Premises

16.1 Entry to Premises by Landlord . Landlord acknowledges that Tenant is in the business of developing and commercializing genetic research and Landlord agrees to take all reasonable steps not to interfere with the rendering of such services and in accordance with this Section 16.1. Landlord shall have the right, upon twenty-four (24) hours prior written notice (except in the event of an emergency, in which case no prior notice shall be required) to enter the Premises at all reasonable times for the purpose of: (a) inspecting the same; (b) making any repairs to the Premises and performing any work therein that may be necessary by reason of (i) ongoing construction on adjacent floors, or (ii) Tenant’s default under the terms of this Lease; (c) exhibiting the Premises for the purpose of sale, ground lease, financing or mortgage; and (d) exhibiting the Premises (during the final twelve (12) months of the Term) to prospective tenants, but only if all such showings are accompanied by a representative of Tenant if so requested by Tenant; provided; however, that all such entries and repairs shall be: (i) completed promptly in a good workmanlike manner; (ii) performed so as to cause the least practical interference to Tenant’s business and Tenant’s use of the Premises, and (iii) subject, in all events, to Tenant’s reasonable security precautions. If Landlord’s entry materially and substantially interferes with the conduct of Tenant’s business and/or causes damage to Tenant’s property (and the entry is not caused by Tenant’s negligence or willful misconduct), then in such event Base Rent, Additional Rent and any other sums due and payable under this Lease shall abate in proportion to the extent of the interference and Landlord shall be liable for any damage to Tenant’s property.

ARTICLE 17

Notices and Certificates

17.1 Notices and Certificates . Any notice, statement, certificate. request or demand required or permitted to be given or delivered in this Tease shall be in writing, sent by hand delivery to the address shown at the beginning of this Lease, or sent by registered or certified mail, postage prepaid, return receipt requested, or overnight express services, prepaid with proof of delivery, addressed, as the case may be, to Landlord at the address shown at the beginning of this Lease, and to Tenant at the address shown at the beginning of this Lease, or to such other addresses as Landlord or Tenant shall designate in the manner herein provided. Such notice, statement, certificate, request or demand shall be deemed to have been given on the date mailed as aforesaid in any post office or branch post office regularly maintained by the United States Government, or in the case of overnight express services, on the date of pick-up as verified by such service, except for notice of change of address or revocation of a prior notice, which shall only be effective upon receipt.

17.2 Certificate . Within fifteen (15) days after request by the other party, Landlord or Tenant, from time to time and without charge, shall deliver to the requesting party or to a person, firm or corporation specified by the requesting party, a duly executed and acknowledged instrument, certifying:

(a) that this Lease is unmodified and in full force and effect, or if there has been any modification, that the Lease is in full force and effect, as modified, and identifying the date of any such modification;

(b) whether such party knows or does not know, as the case may be, of any default in the performance of the terms, covenants, and conditions of this Lease, and specifying the nature of such defaults, if any;

(c) whether or not there are any then existing set-offs or defenses by either party to the enforcement of the terms, covenants, and conditions of this Lease and any modification thereof, and if so, specifying them;

(d) the date to which the Base Rent and Additional Rent have been paid; and

(e) information with regard to other lease terms or conditions as may be requested by any existing or prospective lender or purchaser.

Any such instrument may be relied upon by any party which receives such instrument.

ARTICLE 18

Covenant Of Quiet Enjoyment

18.1 Quiet Enjoyment . Tenant, subject to the terms and provisions of this Lease, on payment of the Rent and observing, keeping and performing all the terms and provisions of this Lease on its part to be observed, kept and performed shall lawfully, peaceably and quietly, within the context of an urban environment, have, hold and enjoy the Premises during the term hereof on and after the Commencement Date without hindrance or ejection by Landlord and any persons lawfully claiming under Landlord, and Landlord warrants and forever agrees to defend Tenant’s interest under this Lease against the claims of any and all persons other than those claiming by, through, or under Landlord.

ARTICLE 19

Certain Rights Reserved to Landlord

19.1 Certain Rights Reserved to Landlord . Landlord reserves the following rights:

(a) To establish associations or governing bodies for the Building;

(b) To name the Building and/or the Project and to change the name or street address of the Building;

(d) During the last one hundred eighty (180) days of the Term, but only after such time as Tenant shall have vacated the Premises and delivered possession of same to Landlord, to decorate, remodel, repair, alter or otherwise prepare the Premises for reoccupancy, provided that the Expiration Date shall be the date that Landlord shall first enter into the Premises to decorate, remodel, repair, alter or otherwise prepare the Premises for reoccupancy and after such date Tenant shall no longer be obligated to pay rental for the Premises or be bound by any other obligation under the Lease except for such obligations that expressly survive the Expiration Date;

(e) To constantly have pass keys to the Premises;

(f) To install, maintain, use, repair and replace pipes, ducts, conduits, wires and structural elements leading through the Premises in locations which will not materially interfere with “tenant’s use of the Premises for an extended duration;

(g) At any time in the event of an emergency, or otherwise at reasonable times, to take any and all measures, including inspections, repairs, alterations, additions and improvements to the Premises or to the Building, as may be necessary or desirable for the safety, protection or preservation of the Premises or the Building or the Landlord’s interests, or as may be necessary or desirable in the operation or improvement of the Building or in order to comply with all laws, orders and requirements of any governmental or other authority; and

(h) To show the Building to prospective purchasers, lenders and tenants upon reasonable notice to Tenant, and in such a manner that does not materially and substantially interfere with the conduct of Tenant’s business.

ARTICLE 20

Miscellaneous Provisions

20.1 End of Term . At the end of the Term, Tenant will promptly quit and surrender the Premises broom-clean, in good order and repair, ordinary wear and tear and damage caused by casualty excepted. If Tenant is not then in default, Tenant may remove from the Premises any trade fixtures, equipment and movable furniture placed in the Premises by Tenant, whether or not such trade fixtures or equipment are fastened to the Building; provided , however , that Tenant will not remove any trade fixtures or equipment without Landlord’s prior written consent or if the removal of such fixtures or equipment will result in impairing the structural strength of the Building.

Whether or not Tenant is in default, Tenant will remove any Alteration if Landlord has so requested in accordance with Section 6.1. Tenant will fully repair any damage occasioned by the removal of any trade fixtures, equipment, furniture, or Alteration. All trade fixtures, equipment, furniture, inventory, effects, and Alterations on the Premises after the end of the Term will be deemed conclusively to have been abandoned and may, upon seventy-two (72) hours prior notice to Tenant, be appropriated, sold, stored, destroyed or otherwise disposed of by Landlord without notice to Tenant or any other person and without obligation to account for them, and Tenant will pay Landlord for all expenses incurred in connection with such property, including without limitation the cost of repairing any damage to the Building or Premises caused by the removal of such property. Tenant’s obligation to observe and perform this covenant will survive the expiration or other termination of this Lease.

20.2 Late Charges; Interest . Tenant hereby acknowledges that late payment by Tenant to Landlord of Base Rent, Additional Rent, or other sums due hereunder will cause Landlord to incur costs not contemplated by this Lease, the exact amount of which will be extremely difficult to ascertain. Such costs include, but are not limited to, processing and accounting charges and late charges which may be imposed upon Landlord by the terms of any mortgage or trust deed covering the Building. Accordingly, if any installment of Base Rent, Additional Rent, other Rent or any other sum due from Tenant shall not be received by Landlord within five (5) days after such amount is due, then, without any notice, such installment or sum shall bear interest retroactively from the date due until paid at the lesser of the highest rate allowed by law or two percent (2%) per month. In addition, Tenant shall pay to Landlord any reasonable, out-of-pocket attorney’s fees, court costs and other expenses (including out-of-pocket costs, fees and expenses incurred in connection with any litigation) incurred by Landlord by reason of Tenant’s failure to pay such installment or sum or the interest accrued thereon.

20.3 Brokers . Each of Tenant and Landlord warrants to the other that it has had no dealings with any real estate broker or agents in connection with the negotiation of this Lease except for the brokers identified in Sections 1.1(q) and 1.1(r), above (collectively, the “Brokers”) whose commissions shall be paid by Landlord pursuant to separate written agreement(s). In the event any claim is made for brokerage commissions arising out of Tenant’s acts by any person or entity other than Brokers, Tenant hereby agrees to indemnify and hold Landlord harmless from and against any and all such damages and liabilities, including, without limitation, court costs, reasonable attorneys’ fees and other expenses of litigation, incurred by Landlord in connection with any such claim. In the event any claim is made for brokerage commissions arising out of Landlord’s act by any person or entity other than Brokers, Landlord hereby agrees to indemnify and hold Tenant harmless from and against any and all such damages and liabilities, including, without limitation, court costs, reasonable attorneys’ fees and other expenses of litigation, incurred by Tenant in connection with any such claim.

20.4 Holdover . If Tenant shall hold over after the expiration of the Term or of Tenant’s right of possession Tenant shall be deemed to be a tenant from month-to-month, at a Base Rent, payable in advance, equal to one and one-half (11/2) times the Base Rent payable during the final month of the Term, and Tenant shall be bound by all of the other terms, covenants and agreements of this Lease as the same may apply to a month-to-month tenancy, including, but not limited to, the requirement to pay Additional Rent. Nothing contained herein shall be construed to give Tenant the right to hold over at any time, and Landlord may exercise any and all remedies at law or in equity to recover possession of the Premises, as well as any damages incurred by Landlord, due to Tenant’s failure to vacate the Premises and deliver possession to Landlord as herein provided.

20.5 Limitation on Liability . In no event shall Landlord at any time be liable to Tenant for any damages, costs, or expenses in excess of Landlord’s interest in the Property. All judgments against Landlord shall be enforced only against such interest and not against any other present or future asset of Landlord. In no event shall Tenant make any claim against or seek to impose any personal liability upon Landlord, any general or limited partner or member of Landlord, or any principal of any firm, limited liability company or corporation that may hereafter become the Landlord, or any agent or employee of any of them. Tenant hereby waives any rights Tenant may now or hereafter have of recourse against any such person or against any present or future asset of such person. Without limiting the foregoing, the term “Landlord” as used throughout this Lease shall be limited to mean and include only the owner or owners at the time in question of the Premises and this Lease. Landlord or the grantor shall turn over to the grantee all monies and security, if any, then held by Landlord or such grantor on behalf of Tenant and shall assign to such grantee all right, title and interest of Landlord or such grantor thereto, it being intended that the covenants and agreements contained in this Lease on the part of Landlord to be performed shall, subject as aforesaid, be binding on Landlord, its successors and assigns.

20.6 Force Majeure . The period of time during which Landlord or Tenant is prevented or delayed in the performance of any of its obligations under this Lease due to unavoidable delays caused by fire, catastrophe, strikes or labor trouble, civil commotion, Acts of God or the public enemy, governmental prohibitions or regulation or inability to obtain materials by reason thereof; or other causes beyond Landlord’s or Tenant’s reasonable control, shall be added to Landlord’s or Tenant’s time for performance thereof, and the affected party shall have no liability by reason thereof, except that there shall be no such excuse as to Tenant’s obligations to pay Rent or other sums due to Landlord hereunder.

20.7 Effect of Captions . The captions or legends on this Lease are inserted only for convenience of reference or identification of the particular articles and sections. They are in no way intended to describe, interpret, define or limit the scope, extent or intent of this Lease, or any article, section or provision thereof.

20.8 Tenant Authorized to Do Business in Colorado . Tenant represents and covenants that it is and throughout the Term of this Lease shall be authorized to do business in the State of Colorado.

20.9 Authority . Tenant represents and warrants that Tenant’s entering into this Lease has been duly authorized by all requisite action on the part of Tenant, the signatory on behalf of Tenant has the authority to execute this Lease on behalf of and bind Tenant, and this Lease is the valid and binding obligations of Tenant, enforceable in accordance with its terms. Landlord represents and warrants that Landlord’s entering into this Lease has been duly authorized by all requisite action on the part of Landlord, the signatory on behalf of Landlord has the authority to execute this Lease on behalf of and bind Landlord, and this Lease is the valid and binding obligations of Landlord, enforceable in accordance with its terms.

20.10 Execution in Counterparts . This Lease may be executed in one or more counterparts, each one of which shall be deemed an original and all of which shall constitute collectively but one agreement.

20.11 Recordation . Neither Landlord nor Tenant shall record this Lease.

20.12 Law Governing Effect and Gender . This Lease shall be construed in accordance with the laws of the State of Colorado and shall be binding upon the parties hereto and their respective legal representatives, successors and assigns except as expressly provided otherwise. Use of the neuter gender shall be deemed to include the masculine and feminine, as the sense requires. Any reference to successors and assigns of Tenant is not intended to constitute a consent to any assignment or sublease by Tenant but has reference only to those instances in which Landlord may later give consent to a particular assignment or sublease as required by the provisions of this Lease.

20.13 Amendments . This Lease shall not be amended except by a written instrument duly executed on behalf of Landlord and Tenant.

20.14 Waiver . The waiver by Landlord or Tenant of any term, covenant or condition herein contained shall not be effective unless in writing and signed by the waiving party and any such waiver shall not be deemed to be a waiver of such term, covenant or condition for any subsequent breach of the same or any other term, covenant or condition herein contained. The subsequent acceptance of Rent by Landlord shall not be deemed to be a waiver of any preceding default by Tenant of any term, covenant or condition of this Lease, other than the failure of Tenant to pay the particular Rent so accepted, regardless of Landlord’s knowledge of such preceding default at the time of the acceptance of such Rent.

20.15 Complete Agreement . This Lease contains and embraces the entire agreement between the parties hereto and it or any part of it may not be changed, altered, modified, limited, terminated, or extended orally or by any agreement between the parties unless such agreement be expressed in writing, signed and acknowledged by the parties hereto, their legal representatives, successors or assigns, except as may be expressly otherwise provided herein.

20.16 Inability to Perform; Covenants Independent . This Lease and the obligations of Tenant hereunder shall not be affected or impaired because Landlord is unable to fulfill any of its obligations hereunder or is delayed in doing so except as otherwise specifically provided in this Lease. It is the intent of the parties that this Lease be

construed as if the covenants herein between Landlord and Tenant are independent and are not dependent and that Rent shall be payable without offset, reduction or abatement for any cause except as otherwise specifically provided in this Lease. In the event that Landlord shall be liable to Tenant for any sums or other matters, either arising out of this Lease or otherwise, Tenant shall not have the right to offset or deduct such liability of Landlord to Tenant against or from the Rent due to Landlord or others pursuant to the terms of this Lease except as otherwise specifically provided in this Lease.

20.17 Cumulative Remedies . No remedy or election hereunder shall be deemed exclusive but shall, whenever possible, be cumulative with all other remedies at law or in equity.

20.18 Attorneys’ Fees . In the event any action or proceeding is brought by either party against the other under this Lease, the prevailing party, whether by judgment or out of court settlement, shall be entitled to recover the fees of its attorneys in such action or proceeding, including costs of appeal, if any, plus court costs and other expenses of litigation.

20.19 No Merger . The voluntary or other surrender of this Lease by Tenant, or a mutual cancellation hereof, shall not work a merger of this Lease, unless Landlord otherwise elects, and shall either terminate any or all existing subleases or concessions, or operate as an assignment thereof to Landlord, whichever Landlord shall elect.

20.20 Invalidity of Particular Provisions . If any term or provision of this Lease or the application thereof to any person or circumstances shall, to any extent, be invalid or unenforceable, the remainder of this Lease, or the application of such term or provision to persons or circumstances other than those as to which it is held invalid or unenforceable, shall not be affected thereby and each term and provision of this Lease shall be valid and he enforced to the fullest extent permitted by law.

20.21 Execution of Lease . The submission of this document for examination and negotiation does not constitute an offer to lease, or a reservation of, or option for, the Premises and this document becomes effective and binding only upon the execution and delivery hereof by Landlord and by Tenant. All negotiations, considerations, representations and understandings between Landlord and Tenant are incorporated herein and may be modified or altered only by agreement in writing between Landlord and Tenant.

20.22 Relationship of the Parties . Nothing contained herein shall be deemed or construed by the parties hereto nor by any third party as creating the relationship of principal and agent or of partnership or of joint venture between the parties hereto, it being understood and agreed that neither the method of computation of rent nor any other provision herein contained, nor any acts or the parties hereto, shall be deemed to create any relationship between the parties hereto other than Landlord and Tenant.

20.23 Disputes and Controversies . The parties hereby agree, unless otherwise specifically set forth in the Lease or any amendment thereto, that all disputes between the parties will be settled by virtue of negotiation and upon failure to resolve such disputes by negotiation, that all claims or disputes, whether by the Tenant or by the Landlord, shall be resolved by bringing an action in the District Court of the City and County of Broomfield, Colorado, and that all cases and in all disputes venue will be in the City and County of Broomfield, Colorado. Such venue and dispute resolution shall not be changed except by specific amendment to this Lease in writing signed by the parties. The parties hereby agree that such venue and dispute resolution terms are reasonable for all purposes of this Lease.

20.24 Memorandum of Lease . Tenant may, at Tenant’s sole cost and expense, record a memorandum of this Lease in the local registry in which the Property is located, in form and substance reasonably acceptable to Landlord and Tenant.

[The remainder of this page intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have execute this Lease on the date first above written:


LANDLORD:		TENANT:

ARISTA PLACE, LLC, a Colorado limited liability company		ARCA DISCOVERY, INC. , a Delaware corporation

By:	/s/ David P. Hostetler	By:	/s/ Patrick Wheeler
Name:	David P. Hostetler	Name:	Patrick Wheeler
Title:	Manager	Title:	VP Finance

EXHIBIT A-1

SITE PLAN/BUILDING

[Omitted]

A-1

EXHIBIT A-1

PREMISES

[Omitted]

A-1-1

EXHIBIT B

LEGAL DESCRIPTION

B. Legal; Lot 5, Filing 6, Broomfield Urban Transit Village.

B-1

EXHIBIT C

OPTION TO EXTEND TERM

Tenant shall have the right to extend the term of this Lease for two (2) additional three (3) year periods (collectively, the “Extended Terms”, and each, an “Extended Term”), on and subject to the terms of this Exhibit C.

First Extended Term . The first Extended Term, if exercised by Tenant, shall commence upon the expiration of the primary 5-year term of this Lease and shall expire on the date that is three (3) years after such date. Tenant must exercise its right to extend the Term for the first Extended Term, if at all, by written notice to Landlord given not later than the date that is one hundred eighty (180) days prior to the expiration date of the primary 5-year term of this Lease. All of the terms and conditions of the Lease shall remain in full force and effect during the first Extended Term, except for the amount of Base Rent, which shall be the Market Rate (as defined below).

Second Extended Term . The second Extended Term, if exercised by Tenant, shall commence upon the expiration of the first Extended Term and shall expire on the date that is three (3) years after such date. If the Tenant fails to exercise the first Extended Term, the option to extend for the second Extended Term shall be null and void. Tenant must exercise its right to extend the Term for the second Extended Term, if at all, by written notice to Landlord given not later than the date that is one hundred eighty (180) days prior to the expiration date of the first Extended Term. All of the terms and conditions of the Lease shall remain in full force and effect during the second Extended Term, except for the amount of Base Rent, which shall be the Market Rate.

Definition of Market Rate . “Market Rate” shall mean the annual amount that a willing tenant would pay and a willing landlord would accept, in an arm’s length transaction, as consideration for office space comparable to the Premises (taking into account such factors as quality, size, configurations, geographic and physical location of the Premises) giving appropriate consideration to the duration of the period (3 years) during which the rate will apply, and other terns and provisions of this Lease that will be in effect with respect to and/or during such period, minus any savings to Landlord on account of not having to provide any tenant improvement allowance, perform any Landlord work or incur any other expenses which are customary in connection with the leasing of comparable space.

Landlord and Tenant will have thirty (30) days after Tenant exercises an extension option within which to agree on the then Market Rate of the Premises for such Extended Term. If they agree on the initial monthly Base Rent for such Extended Term within thirty (30) days, they will amend the Lease by stating the monthly Base Rent for such Extended Term. If they are unable to agree on the monthly Base Rent within said thirty (30) day period, then Tenant shall have the right to withdraw its exercise of the extension option by written notice thereof to Landlord given within five (5) business days after the end of such thirty (30) day period. In the event that Tenant does not so withdraw the exercise of its option, then Fixed Monthly Rent will be then “Market Rate” of the Premises as determined by the appraisers pursuant to this paragraph. Within seven (7) days after the expiration of said thirty (30) day period, Landlord and Tenant will each appoint a real estate appraiser with at least five (5) years’ full-time commercial appraisal experience in the area in which the Premises are located to appraise the then Market Rate of the Premises. If either Landlord or Tenant does not appoint an appraiser within ten (10) days after the other has given notice of the name of its appraiser, and if such party does not give notice to the other of its appraiser, then the party who has sent the notice of its appraiser may send a second notice (“Final Request For Appraiser”), and if the other party does not give notice of its appraiser within ten (10) days of receipt of such Final Request For Appraiser, the single appraiser appointed will be the sole appraiser and will set the then Market Rate value of the Premises within thirty (30) days. If two (2) appraisers are appointed pursuant to this paragraph, they will meet promptly and attempt to set the then Market Rate of the Premises. If they arc unable to agree within thirty (30) days after the second appraiser has been appointed, but their respective final determinations of Market Rate rent are within five percent (5%) of each other, their final determinations of Market Rate shall be averaged. If their respective final determinations are not within five percent (5%) of each other, the two appraiser shall attempt to select a third appraiser meeting the qualifications stated in this paragraph within ten (10) days after the last day the two (2) appraisers are given to set the then Market Rate of the Premises. If the two appraisers cannot agree on a third appraiser, either party may petition the District Court for the City and County of Broomfield, Colorado for appointment of such appraiser. The third appraiser, however selected, must be a person who has not previously acted in any capacity for either Landlord or Tenant. Within thirty (30) days after the selection of the third appraiser, the third appraiser shall be limited to selecting which of the two final determinations of Market Rate is most close to the third appraiser’s determination of Market Rate.

C-1

EXHIBIT “D”

WORKLETTER AGREEMENT

THIS WORKLETTER is dated February 8, 2008, by and between ARISTA PLACE, LLC, a Colorado limited liability company (“Landlord”) and ARCA DISCOVERY, INC., a Delaware corporation (“Tenant”).

R E C I T A L S:

1. This Workletter is attached to and forms a part of that certain Office Lease dated February 8, 2008 (“Lease”), pursuant to which Landlord has leased to Tenant office space in that building known as 8001 Arista Place, Broomfield, Colorado.

2. The parties have agreed to make certain improvements to the Premises, upon the terms and conditions contained in the Lease and this Workletter. Landlord shall perform the improvements set forth in Exhibit D-1 as Landlord’s base work, and before any Tenant Improvements by Tenant.

3. Tenant Improvements . Landlord has granted to Tenant an allowance of up to Forty Dollars and Forty-Five cents ($40.45) per rentable square foot of the Premises, (the “Tenant Improvement Allowance”), for completion of wall to wall Tenant Improvements by Tenant in accordance with the Space Plan (hereinafter defined). Except as provided herein, the Tenant Improvement Allowance is exclusively for Tenant Improvements in the Premises, including hard and soft costs associated with the design, planning, permitting and construction of the Tenant Improvements (including, without limitation, professional fees for Tenant’s architect, engineer and project manager). In the event the Tenant Improvement Allowance is not used on or before the first anniversary of the Lease commencement date, Landlord shall retain such unused portion of the Tenant Improvement Allowance, and Tenant shall have no further rights thereto or hereunder. Upon Landlord’s written request, Tenant shall notify Landlord of the allowance expenditures and outstanding allowance amount during the time that Tenant Improvement construction is ongoing; provided , however , Tenant shall have no obligation to provide such information to Landlord more than one (1) time per month. Tenant is responsible for any and all Tenant Improvement costs, and shall promptly pay such costs, in excess of the Tenant Improvement Allowance. Tenant shall have the work depicted in the Tenant Space Plan and ensuing Construction Drawings (the detailed plans and specifications required to facilitate construction of the design reflected in Tenant Space Plan) (the “Tenant Work”) constructed with, unless otherwise specified, Building standard materials and in a good and workmanlike manner pursuant to the schedule provided for herein, subject, however, to extensions equal to the delays suffered by Tenant and caused by Landlord or by strike, lockouts, fire or other casualty loss, acts of God, unavailability of materials, hostile or war like action, riot or other causes beyond Tenant’s reasonable control. The Tenant Work, as modified from time to time pursuant to the provisions of this Workletter, shall be known as the “Tenant Improvements”. Subject to the foregoing limitations, the Construction Drawings and any other architectural, engineering or project management fees set forth below shall be paid for out of the Tenant Improvement Allowance as part of the costs of the Tenant Improvements. Landlord shall pay the Tenant Improvement Allowance to Tenant in three (3) installments upon written notice from Tenant of the completion of work related to Tenant’s Work with the supporting documentation for such work.

4. Tenant Space Plan . Landlord and Tenant agree that Tenant shall retain its own architect (“Tenant’s Architect”), which Tenant’s Architect shall be reasonably approved by Landlord, to prepare the space layout and improvement plan for the Premises (the “Space Plan”), and Landlord shall provide Tenant a Space Plan allowance of $.15 per square foot, which allowance shall be in addition to the Tenant Improvement Allowance. So long as Tenant and Tenant’s project manager shall approve the bids from Landlord’s designated mechanical, structural and electrical engineers, Tenant shall utilize Landlord’s designated mechanical, structural and electrical engineers to work with Tenant’s Architect in preparing the Space Plan and the Construction Drawings (hereinafter defined). Once the Space Plan has been completed by Tenant’s Architect, Tenant and Tenant’s project manager shall provide the proposed Space Plan to Landlord for Landlord’s review and approval. Landlord shall either approve the Space Plan or provide specific written comments regarding items on the Space Plan which it does not approve, within five (5) business days after receipt of the proposed Space Plan. If Landlord does not approve the Space Plan, Tenant’s project manager shall cause the revisions to the Space Plan to address Landlord’s disapproved items, and re-submit the Space Plan to Landlord, in which case the foregoing procedure shall be followed until such time that Landlord approves Tenant’s Space Plan. If Landlord fails to give its approval or disapproval to the Space Plan within the time frames provided, the Space Plan shall be deemed approved by Landlord.

D-1

5. Construction Drawings . Based upon the approved Space Plan, Tenant’s project manager has caused test fit (“Test Fit”) to be submitted to Landlord, and Landlord shall either approve or provide specific written comments regarding items in the Test Fit which it does not approve within the same time periods and subject to the same provisions as set forth above with respect to the Space Plan. If Tenant delays in providing Landlord the Space Plan or the Test Fit (or any revisions thereto) beyond February 8, 2008, any delays in Tenant’s or Landlord’s construction as a result thereof shall be deemed delays caused by Tenant, and in such case, Landlord shall have a day for day extension to any deadlines set forth herein, or in the Lease. If Landlord delays in approving or commenting upon the Space Plan or the Test Fit (or any revisions thereto) beyond the times set forth in this Workletter Agreement, and such delays actually result in a postponement of the Commencement Date beyond the scheduled Commencement Date, such delays shall be deemed delays caused by Landlord and shall result in the penalties set forth in Section 2,5 of the Lease. All other delays shall be deemed Tenant Delay (other than delays due to force majeure), and in such case, Landlord shall have a day for day extension to any deadlines set forth herein, or in the Lease.

6. Tenant Contractor . Landlord has agreed to March 19, 2008 as the scheduled Commencement Date with the provision that Landlord’s contractor may after such date enter the Premises for the purposes of completing minor work in the bathrooms and outstanding punch-list items, and subject also to any change based on revisions to the Space Plan that Tenant has not submitted to Landlord for approval; provided , however , that Landlord’s contractor shall be allowed to enter after such date and complete such work so long as: (i) such work is performed and completed promptly in a good workmanlike manner; (ii) such entry and work do not interfere with Tenant’s Work, and (iii) subject, in all events, to Tenant’s reasonable security precautions and insurance requirements. If Landlord’s entry and/or work interferes with the conduct of Tenant’s Work, then such event shall constitute a Landlord delay and Tenant shall be entitled to a day for day extension of the Rent Commencement Date.

a. The Premises will be punched by Landlord’s contractor, and any and all subsequent damage to the Premises during Tenant’s Work that is caused by Tenant or Tenant’s contractor shall be the responsibility of Tenant or its contractor, and to the extent there is any delay in the completion of the core/shell caused solely by Tenant’s contractor, such delay shall be a Tenant Delay.

b. Mechanical Systems (Simpson), Fire Sprinkler (Fire Systems West) and Fire Alarm (Duro Electric/Bronco) core and shell subcontractors (collectively referred to as “HVAC/fire/sprinkler Systems Work”) shall be used by Tenant’s contractor so as not to interfere with warranty, tie-in, and testing of these building systems prior to final inspection by the City of core/shell systems; alternatively, should Tenant’s contractor elect not to utilize base building subcontractors, Tenant’s contractor shall not tie-in the HVAC/fire/sprinkler Systems Work until after final inspection by the City. Tenant shall coordinate the HVAC/fire/sprinkler Systems Work in a manner as to meet Tenant’s timelines and the deadlines set forth herein and to avoid Tenant Delay, but also so as not to interfere with Landlord’s final inspections on any and all core/shell systems or any of Landlord’s deadlines.

c. The Building elevator will not available for use by Tenant’s contractor until the City has conducted its final inspection.

d. Tenant’s contractor for Tenant’s Work must satisfy all insurance requirements of Landlord and Landlord’s contractor, and all such insurance shall name Landlord and Landlord’s contractor as additional insureds.

e. Tenant’s contractor shall provide all general conditions items to complete the work (i.e. Trash, Restroom Facilities, Security, etc.)

f. Landlord cannot insure the schedule or budget of the Tenant improvement work and can only control the completion dates for the core/shell. All finishes by Tenant’s contractor shall meet the standard for the tenant finish for a Class A building in the Denver Metropolitan area.

D-2

7. Upon written approval of the Tenant Cost Estimate by Tenant, Landlord, Tenant and Tenant’s project manager shall be deemed to have given final approval to the Construction Drawings, and the costs thereof, and Tenant shall be authorized to proceed with Tenant Improvement construction.

8. Change Orders . If Tenant requests changes in the Tenant Work that delays Tenant’s completion of the Tenant Improvements, then such delay shall constitute a Tenant Delay.

9. Completion and Commencement of Rent . The term of the Lease shall commence as set forth in the Lease.

10. Failure to Perform . If Tenant delivers to Landlord the Construction Drawings and/or Tenant Cost Estimate and Landlord fails to accept or reject such Drawings or Estimate (or revised Drawings and/or Estimate) as provided in Paragraphs #5 and #6 hereof within the period provided herein, Tenant may, in its sole discretion, deem Landlord to have approved same, and proceed with construction.

11. Construction Administration . Tenant shall coordinate and administer all activities of Tenant’s contractor(s) in the performance of Tenant’s Improvements in accordance with the plans and specifications, and rules and regulations herein. Landlord’s project manager shall attend weekly construction meetings with Tenant’s Project Manager and contractors. Tenant agrees that it will not contract with any contractor, laborer or material supplier to perform any improvements in the Premises without providing Landlord with notice ten (10) days prior to any improvements and requiring said contractor, laborer or material supplier to execute an agreement acknowledging non-liability for payment by Landlord in accordance with C.R.S. § 38-22-105.5, as amended from time to time and to carry insurance in the form and limits requested by Landlord.

12. Miscellaneous .

a. Except to the extent otherwise indicated herein, the initially capitalized terms used in this Workletter Agreement shall have the meaning assigned to them in the Lease.

b. The terms and provisions of this Tenant Workletter are intended to supplement and are intended as an addendum to the Lease and are specifically subject to all the terms and provisions of the Lease. In the event of conflict between the terms of this Tenant Workletter and the Lease, then the provisions of the Workletter shall govern.

c. Prior to the date the Premises are ready for occupancy Landlord’s contractor and Tenant and Tenant’s project manager shall inspect the Premises and jointly complete a “punch list” of incomplete or defective work, and thereafter Landlord shall exercise due diligence to cause such punch list items to be completed within thirty (30) days following the inspection date (except for any punch list items which, despite due diligence, cannot be completed within said thirty (30) day period). Punch list items which do riot prevent Tenant from occupying the premises and generally conducting its business shall riot be deemed as a Landlord delay with respect to the Commencement Date.

d. This Tenant Workletter may not be amended or modified other than by supplemental written agreement executed by authorized representatives of the parties hereto.

e. No waiver of any default of the Tenant hereunder shall be implied from any omission by the Landlord to take any action on account of such default if such default persists or be repeated, and no express waiver shall affect any default other than the default specified in the express waiver, and that only for the time and to the extent therein stated.

f. Landlord neither warrants nor guarantees the accuracy of any estimated Costs or Tenant Cost Estimates.

g. Each of the parties undertakes and agrees to, upon written request, meet or provide written response, as the case may be, within three (3) business days of such written request, except as otherwise provided in this Workletter Agreement. Any delay caused by either party’s failure to do so shall be deemed to be a delay by such party.

D-3

h. The terms and provisions of this Exhibit D, and the attached D-1 are intended to supplement and are intended as an addendum to the Lease and are specifically subject to all the terms and provisions of the Lease. in the event of conflict between the terms of this Exhibit D (and D-1) and the Lease, then the provisions of this Exhibit D (and D-1) shall govern.


LANDLORD:		TENANT:

ARISTA PLACE, LLC, a Colorado limited liability company		ARCA DISCOVERY, INC., a Delaware corporation

By:	/s/ David P. Hostetler	By:	/s/ Patrick Wheeler
Name:	David P. Hostetler	Name:	Patrick Wheeler
Title:	Manager	Title:	VP Finance

D-4

EXHIBIT “D-I”

LANDLORD’S BASE BUILDING WORK

Landlord shall provide, at Landlord’s expense, the following improvements (“Landlord’s Work”):

1. Shell : Landlord shall provide the structural frame of the building, roof structures and membrane with a minimum R value to meet applicable codes of the City and County of Broomfield, floor with a minimum of 50 lbs per SF live load and a partition load of 20 lbs per SF (leveled and troweled smooth as approved by Landlord’s General Contractor and ready for finishes by Tenant) and exterior walls and glazing. Construct perimeter wall furring above and below window units and perimeter columns complete with insulation (required by applicable codes) and gypsum board. Furnish and install windowsill extensions (if applicable), color and finish to be approved by Tenant. Interior columns to be framed with gypsum board taped and sanded smooth. No ceilings by Landlord (space to be exposed to structure above). Lightweight concrete slab on deck by Landlord, ready receive ensuing finishes by Tenant.

2. Signage : Landlord shall review and approve all signage elements as detailed in Tenant’s plans and specifications, which shall be based upon Landlord’s design guidelines. Landlord shall furnish and install a building directory in the main lobby; general identification/directional signage at toilet rooms and exit stairwells; building standard Tenant signage at Premises entrance; exterior signage for building identification to be negotiated between Tenant and Landlord.

3. Lobbies, Elevators, Corridors, and Demising Walls : Building standard lobbies, elevators, common corridors to be constructed and finished by Landlord to Landlord’s specifications as part of core and shell construction. Common area corridors (where applicable) shall have gypsum wall board to underside of structure on common corridor and tenant side and paint/or wall covering on common corridor side. Tenant’s general contractor shall have reasonable access to the building for material delivery and handling. Landlord’s architect to provide finish selection samples to Tenant at Tenant’s request for design coordination efforts.

4. Water : Cold water supply line shall be available from a central distribution point on the floor with the understanding that if Tenant requires, the Landlord will allow Tenant to install, at Tenant’s sole cost, a domestic hot water heater in a proposed location, as approved by Landlord. Tie-in and shut-off valve by Tenant. Landlord shall furnish one (I) accessible Tenant rough-in wet column per floor.

5. Sewer : Sanitary waste line shall be available for tie in by Tenant at a reasonable central point in the ceiling space of the floor below. Tenant to coordinate with Landlord for access into the ceiling space of the Tenant below for access.

6. Fire Sprinkler System : Landlord will furnish and install in a standard grid configuration a complete fire protection system per NFPA requirements for office occupancy including heads turned up prior to any Tenant Improvement Work. Tenant shall be responsible for all final distribution to comply with applicable codes.

7. Core Service Areas : Toilet rooms (fully ADA compliant within common area and Tenant’s demised premises to include the furnishing and install of ceramic tile on floor and wet walls, painted gypsum drywall or vinyl wall covering on remaining walls; vanity with underhung porcelain lavatories and full width mirrors; baked enamel toilet partitions; wall mounted tank type water closets and wall hung urinals), telephone, electrical rooms, stairwells, janitor closets, service entry and mechanical rooms are to be provided complete;

8. Security : Furnish and install control key card access for after hour access at a minimum of two building entrances and one elevator with access to Tenant’s space.

9. Life Safety : Furnish and install fire management system as required by code; furnish and install one (1) tire extinguisher on each landing of each stair; furnish and install code required exit and emergency lighting for all public areas

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10. Electrical : Electrical service to be provided via a 400 amp 480 volt panel on each floor to be shared by all tenants on a pro-rata basis with a minimum guarantee to Tenant of 15 watts per RSF for HVAC loads, 2 watts per RSF for lighting and 4.5 watts per RSF for office equipment loads and capacity for convenience power (one circuit per 170 RSF). Connection by Tenant. Landlord shall provide such temporary interior “stumble” lighting as reasonably necessary to minimally illuminate the space as needed prior to tenant improvement work; all other lighting shall be by Tenant. Furnish and install exterior site lighting per City and County of Broomfield Standards.

11. HVAC : VVT Mechanical System, including RTU with DDC controls with VAV boxes sized at 400 SF per ton. Furnish and install primary trunk ducts from air handlers to vicinity of each zone serviced; Primary air duct readily accessible on floor; provide exhaust systems for base building spaces as required. All downstream distribution ductwork, diffusers, etc. by Tenant.

12. Telephone : Main telephone terminal board at location outside the premises reasonably selected by Landlord for Tenant’s connection to telephone service. A 1” conduit for telephone service shall be stubbed into the Premises from the building’s main telephone distribution point.

13. Course of Construction — Temporary Services : During the period of Tenant Improvement work, Landlord shall provide for use by Tenant and its contractors reasonable access to temporary services, including electrical service and water.

14. Course of Construction — Building Dry-In : Landlord shall provide the Tenant’s Leased Premises in code compliant “dried in” conditions (roof, glazing, gas, water, electrical as provided herein) as acceptable by the Tenant on or before March 3, 2008 in order for building to accept and contain temporary heat as needed in order to maintain standard construction sequence.

15. Fees : Landlord shall pay all water and sewer, tap fees and standard impact fees for the core and shell building shell where applicable. Tenant shall be responsible for all fees, permits, etc., for all Tenant Improvement work.

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EXHIBIT E

Rules and Regulations

[Omitted]

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Exhibit 10.10

LOAN AND SECURITY AGREEMENT

THIS LOAN AND SECURITY AGREEMENT (this “ Agreement ”) dated as of the Effective Date between SILICON VALLEY BANK , a California corporation (“ Bank ”), and ARCA Discovery, Inc. , a Delaware corporation (“ Borrower ”), provides the terms on which Bank shall lend to Borrower and Borrower shall repay Bank. The parties agree as follows:

ACCOUNTING AND OTHER TERMS

Accounting terms not defined in this Agreement shall be construed following GAAP. Calculations and determinations must be made following GAAP. Capitalized terms not otherwise defined in this Agreement shall have the meanings set forth in Section 13. All other terms contained in this Agreement, unless otherwise indicated, shall have the meaning provided by the Code to the extent such terms are defined therein.

LOAN AND TERMS OF PAYMENT

2.1 Promise to Pay . Borrower hereby unconditionally promises to pay Bank the outstanding principal amount of all Credit Extensions and accrued and unpaid interest thereon as and when due in accordance with this Agreement.

2.1.1 Growth Capital Line A.

(a) Availability . Subject to the terms and conditions of this Agreement, during the GC Line A Draw Period, Bank shall make advances (each, a “ GC Line A Advance ” and, collectively, “ GC Line A Advances ”) not exceeding the Growth Capital Line A. After repayment, no GC Line A Advance may be reborrowed. GC Line A Advances made on or after the Effective Date and on or before December 31, 2007 are called “ GC Line A Tranche One Advances ,” and GC Line A Advances made after December 31, 2007 and on or before the last day of the GC Line A Draw Period are called “ GC Line A Tranche Two Advances .” If Borrower has not advanced all of Growth Capital Line A by the end of the GC Line A Draw Period, any such amounts not advanced as of such date shall be added to, and become part of the Growth Capital Line B.

(b) Repayment . The period of time commencing on the Effective Date and ending on the day immediately prior to the GC Line A Tranche One Amortization Start Date is called the “ GC Line A Tranche One Interest Only Period ,” and the period of time commencing on January 1, 2008 and ending on June 30, 2008 is called the “ GC Line A Tranche Two Interest Only Period .” During the GC Line A Tranche One Interest Only Period, Borrower will make monthly payments to Bank of accrued interest only on the outstanding principal amount of all GC Line A Tranche One Advances, and during the GC Line A Tranche Two Interest Only Period, Borrower will make monthly payments to Bank of accrued interest only on the outstanding principal amount of all GC Line A Tranche Two Advances. GC Line A Advances made and outstanding on July 31, 2007 are payable in thirty (30) consecutive equal monthly installments of principal and interest, beginning on the earlier of (i) the first day of the month following the date which is six months from the date of the first GC Line A Advance or (ii) July 1, 2008 (the “ GC Line A Tranche One Amortization Start Date ”) and ending on the GC Line A Tranche One Maturity Date (the “ GC Line A Tranche One Amortization Period ”). Any GC Line A Advances made after D 31, 2007 and outstanding on the last day of the GC Line A Draw Period are payable in thirty (30) consecutive equal monthly installments of principal and interest, beginning on July 1, 2008 (the “ GC Line A Tranche Two Amortization Start Date ”) and ending on the GC Line A Tranche Two Maturity Date (the “ GC Line A Tranche Two Amortization Period ”).

(c) Prepayment . At Borrower’s option, so long as an Event of Default has not occurred and is not continuing, Borrower shall have the option to prepay without penalty or premium all, but not less than all, of Growth Capital Line A advanced by Bank under this Agreement, provided Borrower (i) provides written notice to Bank of its election to exercise to prepay the Growth Capital Line A at least thirty (30) days prior to such prepayment, and (ii) pays, on the date of the prepayment (A) all accrued and unpaid interest with respect to all outstanding GC Line A Advances through the date the prepayment is made; (B) all unpaid principal with respect to all outstanding GC Line A Advances; and (C) all other sums, if any, that shall have become due and payable hereunder with respect to Growth Capital Line A.

2.1.2 Growth Capital Line B.

(a) Availability . Subject to the terms and conditions of this Agreement, during the GC Line B Draw Period, Bank shall make advances (each, a “ GC Line B Advance ” and, collectively, “ GC Line B Advances ”) not exceeding the Growth Capital Line B. After repayment, no GC Line B Advance may be reborrowed. GC Line B Advances made on or after the Milestone Achievement Date and on or before June 30, 2008 are called “ GC Line B Tranche One Advances ,” and GC Line B Advances made after June 30, 2008 and on or before the last day of the GC Line B Draw Period are called “ GC Line B Tranche Two Advances .”

(b) Repayment . The period of time commencing on the Milestone Achievement Date and ending on the day immediately prior to the GC Line B Tranche One Amortization Start Date is called the “ GC Line B Tranche One Interest Only Period ,” and the period of time commencing on July 1, 2008 and ending on December 31, 2008 is called the “ GC Line B Tranche Two Interest Only Period .” During the GC Line B Tranche One Interest Only Period, Borrower will make monthly payments to Bank of accrued interest only on the outstanding principal amount of all GC Line B Tranche One Advances, and during the GC Line B Tranche Two Interest Only Period, Borrower will make monthly payments to Bank of accrued interest only on the outstanding principal amount of all GC Line B Tranche Two Advances. GC Line B Advances made and outstanding on June 30, 2008 are payable in twenty-four (24) consecutive equal monthly installments of principal and interest, beginning on the earlier of (i) the first day of the month following the date which is six months from the date of the first GC Line B Advance or (ii) January 1, 2009 (the “ GC Line B Tranche One Amortization Start Date ”) and ending on the GC Line B Tranche One Maturity Date (the “ GC Line B Tranche One Amortization Period ”). Any GC Line B Advances made after June 30, 2008 and outstanding on the last day of the GC Line B Draw Period are payable in twenty-four (24) consecutive equal monthly installments of principal and interest, beginning on January 1, 2009 (the “ GC Line B Tranche Two Amortization Start Date ”) and ending on the GC Line B Tranche Two Maturity Date (the “ GC Line B Tranche Two Amortization Period ”).

(c) Prepayment . At Borrower’s option, so long as an Event of Default has not occurred and is not continuing, Borrower shall have the option to prepay without penalty or premium all, but not less than all, of Growth Capital Line B advanced by Bank under this Agreement, provided Borrower (i) provides written notice to Bank of its election to exercise to prepay the Growth Capital Line B at least thirty (30) days prior to such prepayment, and (ii) pays, on the date of the prepayment (A) all accrued and unpaid interest with respect to all outstanding GC Line B Advances through the date the prepayment is made; (B) all unpaid principal with respect to all outstanding GC Line B Advances; and (C) all other sums, if any, that shall have become due and payable hereunder with respect to Growth Capital Line B.

2.2 Payment of Interest on the Credit Extensions.

(a) Interest Rates . Subject to Section 2.2(b), the principal amounts outstanding under Growth Capital Line A and Growth Capital Line B, respectively, shall accrue interest at, during the GC Line A Tranche One Interest Only Period with respect to GC Line A Tranche One Advances, during the GC Line A Tranche Two Interest Only Period with respect to GC Line A Tranche Two Advances, during the GC Line B Tranche One Interest Only Period with respect to GC Line B Tranche One Advances, and during the GC Line B Tranche Two Interest Only Period with respect to GC Line B Tranche Two Advances, a floating per annum rate equal to the Prime Rate, which interest shall be payable monthly in accordance with Section 2.2(f) below. On the GC Line A Tranche One Amortization Start Date with respect to the GC Line A Tranche One Amortization Period, on the GC Line A Tranche Two Amortization Start Date with respect to the GC Line A Tranche Two Amortization Period, on the GC Line B Tranche One Amortization Start Date with respect to the GC Line B Tranche One Amortization Period, and on the GC Line B Tranche Two Amortization Date with respect to the GC Line B Tranche Two Amortization Period, the principal amounts outstanding under Growth Capital Line A and Growth Capital Line B, respectively, shall accrue interest at a per annum rate equal to the Prime Rate, which shall be fixed as of the GC Line A Tranche One Amortization Start Date the GC Line A Tranche Two Amortization Start Date, the GC Line B Tranche One Amortization Start Date, and the GC Line B Tranche Two Amortization Start Date, as the case may be, which interest shall be payable monthly in accordance with Section 2.2(f) below.

(b) Default Rate . Immediately upon the occurrence and during the continuance of an Event of Default, Obligations shall bear interest at a rate per annum which is five percentage points above the rate that is otherwise applicable thereto (the “ Default Rate ”). Payment or acceptance of the increased interest rate provided in this Section 2.2(b) is not a permitted alternative to timely payment and shall not constitute a waiver of any Event of Default or otherwise prejudice or limit any rights or remedies of Bank.

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(c) Adjustment to Interest Rate . Changes to the interest rate of any Credit Extension based on changes to the Prime Rate shall be effective on the effective date of any change to the Prime Rate and to the extent of any such change.

(d) 360-Day Year . Interest shall be computed on the basis of a 360-day year for the actual number of days elapsed.

(e) Debit of Accounts . Bank may debit any of Borrower’s deposit accounts, including the Designated Deposit Account, for principal and interest payments or any other amounts Borrower owes Bank when due. These debits shall not constitute a set-off.

(f) Payments . Unless otherwise provided, interest is payable monthly on the first calendar day of each month. Payments of principal and/or interest received after 12:00 p.m. Pacific time are considered received at the opening of business on the next Business Day. When a payment is due on a day that is not a Business Day, the payment is due the next Business Day and additional fees or interest, as applicable, shall continue to accrue.

2.3 Fees. Borrower shall pay to Bank:

(a) Commitment Fee . A fully earned, non-refundable commitment fee of $7,500.00 (which includes the Bank’s attorney’s fees for drafting and negotiating the initial Loan Documents), on the Effective Date; and

(b) Bank Expenses . All Bank Expenses (including reasonable attorneys’ fees and expenses but excluding the Bank’s attorney’s fees for drafting and negotiating the initial Loan Documents) incurred through and after the Effective Date, when due.

CONDITIONS OF LOANS

3.1 Conditions Precedent to Initial Credit Extension . Bank’s obligation to make the initial Credit Extension is subject to the condition precedent that Borrower shall consent to or shall have delivered, in form and substance satisfactory to Bank, such documents, and completion of such other matters, as Bank may reasonably deem necessary or appropriate, including, without limitation:

(a) duly executed original signatures to the Loan Documents to which it is a party;

(b) duly executed original signatures to the completed Corporate Borrowing Certificate for Borrower, plus all exhibits thereto;

(c) good standing certificates/certificates of foreign qualification from the Secretaries of State of the States of Delaware and Colorado, dated no later than 30 days prior to the Effective Date.

(d) the Perfection Certificate executed by Borrower;

(e) a copy of its Investors’ Rights Agreement, Right of First Refusal and Co-Sale Agreement and Voting Agreement and any amendments thereto;

(f) evidence satisfactory to Bank that the insurance policies required by Section 6.4 hereof are in full force and effect, together with appropriate evidence showing loss payable and/or additional insured clauses or endorsements in favor of Bank; and

(g) payment of the fees and Bank Expenses then due as specified in Section 2.3 hereof.

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3.2 Conditions Precedent to all Credit Extensions . Bank’s obligations to make each Credit Extension, including the initial Credit Extension, is subject to the following:

(a) except as otherwise provided in Section 3.4, timely receipt of an executed Payment/Advance Form;

(b) the representations and warranties in Section 5 shall be true in all material respects on the date of the Payment/Advance Form and on the Funding Date of each Credit Extension; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date, and no Default or Event of Default shall have occurred and be continuing or result from the Credit Extension. Each Credit Extension is Borrower’s representation and warranty on that date that the representations and warranties in Section 5 remain true in all material respects; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date; and

3.3 Covenant to Deliver . Borrower agrees to deliver to Bank each item required to be delivered to Bank under this Agreement as a condition to any Credit Extension. Borrower expressly agrees that the extension of a Credit Extension prior to the receipt by Bank of any such item shall not constitute a waiver by Bank of Borrower’s obligation to deliver such item, and any such extension in the absence of a required item shall be in Bank’s sole discretion.

3.4 Procedures for Borrowing . Subject to the prior satisfaction of all other applicable conditions to the making of a GC Line A Advance or GC Line B Advance set forth in this Agreement, to obtain a GC Line A Advance or GC Line B Advance, as the case may be, Borrower shall notify Bank (which notice shall be irrevocable) by electronic mail, facsimile, or telephone by 12:00 p.m. Pacific time on the Funding Date of such GC Line A Advance or GC Line B Advance. Together with any such electronic or facsimile notification, Borrower shall deliver to Bank by electronic mail or facsimile a completed Payment/Advance Form executed by a Responsible Officer or his or her designee. Bank may rely on any telephone notice given by a person who Bank believes is a Responsible Officer or designee. Bank shall credit GC Line A Advances and GC Line B Advances to the Designated Deposit Account. Bank may make Advances GC Line A Advances or GC Line B Advances under this Agreement based on instructions from a Responsible Officer or his or her designee or without instructions if the GC Line A Advances or GC Line B Advances are necessary to meet Obligations which have become due.

CREATION OF SECURITY INTEREST

4.1 Grant of Security Interest . Borrower hereby grants Bank, to secure the payment and performance in full of all of the Obligations, a continuing security interest in, and pledges to Bank, the Collateral, wherever located, whether now owned or hereafter acquired or arising, and all proceeds and products thereof. Borrower represents, warrants, and covenants that the security interest granted herein is and shall at all times continue to be a first priority perfected security interest in the Collateral (subject only to Permitted Liens that may have superior priority to Bank’s Lien under this Agreement). If Borrower shall acquire a commercial tort claim, Borrower shall promptly notify Bank in a writing signed by Borrower of the general details thereof and grant to Bank in such writing a security interest therein and in the proceeds thereof, all upon the terms of this Agreement, with such writing to be in form and substance reasonably satisfactory to Bank.

If this Agreement is terminated, Bank’s Lien in the Collateral shall continue until the Obligations (other than those arising under the Warrants and inchoate indemnity obligations) are repaid in full in cash. Upon payment in full in cash of the Obligations (other than those arising under the Warrants and inchoate indemnity obligations) and at such time as Bank’s obligation to make Credit Extensions has terminated, Bank shall, at Borrower’s sole cost and expense, release its Liens in the Collateral and all rights therein shall revert to Borrower.

4.2 Authorization to File Financing Statements . Borrower hereby authorizes Bank to file financing statements, without notice to Borrower, with all appropriate jurisdictions to perfect or protect Bank’s interest or rights hereunder, including a notice that any disposition of the Collateral, by either Borrower or any other Person, shall be deemed to violate the rights of Bank under the Code except as permitted hereunder.

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REPRESENTATIONS AND WARRANTIES

Borrower represents and warrants as follows:

5.1 Due Organization, Authorization; Power and Authority . Borrower is duly existing and in good standing as a Registered Organization in its jurisdiction of formation and is qualified and licensed to do business and is in good standing in any jurisdiction in which the conduct of its business or its ownership of property requires that it be qualified except where the failure to do so could not reasonably be expected to have a material adverse effect on Borrower’s business. In connection with this Agreement, Borrower has delivered to Bank a completed certificate signed by Borrower, entitled “Perfection Certificate”. Borrower represents and warrants to Bank that (a) Borrower’s exact legal name is that indicated on the Perfection Certificate and on the signature page hereof; (b) Borrower is an organization of the type and is organized in the jurisdiction set forth in the Perfection Certificate; (c) the Perfection Certificate accurately sets forth Borrower’s organizational identification number or accurately states that Borrower has none; (d) the Perfection Certificate accurately sets forth Borrower’s place of business, or, if more than one, its chief executive office as well as Borrower’s mailing address (if different than its chief executive office); (e) other than a reincorporation from Colorado into Delaware, completed in 2004, Borrower (and each of its predecessors) has not, in the past five (5) years, changed its jurisdiction of formation, organizational structure or type, or any organizational number assigned by its jurisdiction; and (f) all other information set forth on the Perfection Certificate pertaining to Borrower and each of its Subsidiaries is accurate and complete in all material respects (it being understood and agreed that Borrower may from time to time update certain information in the Perfection Certificate after the Effective Date to the extent permitted by one or more specific provisions in this Agreement).

The execution, delivery and performance by Borrower of the Loan Documents to which it is a party have been duly authorized, and do not (i) conflict with any of Borrower’s organizational documents, (ii) contravene, conflict with, constitute a default under or violate any material Requirement of Law, (iii) contravene, conflict or violate any applicable order, writ, judgment, injunction, decree, determination or award of any Governmental Authority by which Borrower or any its Subsidiaries or any of their property or assets may be bound or affected, (iv) require any action by, filing, registration, or qualification with, or Governmental Approval from, any Governmental Authority (except such Governmental Approvals which have already been obtained and are in full force and effect), or (v) constitute an event of default under any material agreement by which Borrower is bound. Borrower is not in default under any agreement to which it is a party or by which it is bound in which the default could reasonably be expected to have a material adverse effect on Borrower’s business.

5.2 Collateral . Borrower has good title to, has rights in, and the power to transfer each item of the Collateral upon which it purports to grant a Lien hereunder, free and clear of any and all Liens except Permitted Liens. Borrower has no deposit accounts other than the deposit accounts with Bank, the deposit accounts, if any, described in the Perfection Certificate delivered to Bank in connection herewith, or of which Borrower has given Bank notice and taken such actions as are necessary to give Bank a perfected security interest therein.

The Collateral is not in the possession of any third party bailee (such as a warehouse) except as otherwise provided in the Perfection Certificate and except for raw materials and inventory at off-site locations. None of the components of the Collateral shall be maintained at locations other than as provided in the Perfection Certificate or as Borrower has given Bank notice pursuant to Section 7.2, except for raw materials and inventory at off-site locations. In the event that Borrower, after the date hereof, intends to store or otherwise deliver any portion of the Collateral, except for raw materials and inventory, to a bailee not listed on the Perfection Certificate, then Borrower will first receive the written consent of Bank and such bailee must execute and deliver a bailee agreement in form and substance satisfactory to Bank.

Except as noted on the Perfection Certificate, Borrower is not a party to, nor is bound by, any material license or other agreement with respect to which Borrower is the licensee (a) that prohibits or otherwise restricts Borrower from granting a security interest in Borrower’s interest in such license or agreement or any other property, or (b) for which a default under or termination of would interfere with the Bank’s right to sell any Collateral. Borrower shall provide written notice to Bank within ten (10) days of entering or becoming bound by any such license or agreement not noted on the Perfection Certificate (other than over-the-counter software that is

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commercially available to the public). Borrower shall take such steps as Bank requests to obtain the consent of, or waiver by, any person whose consent or waiver is necessary for (x) all such licenses or agreements to be deemed “Collateral” and for Bank to have a security interest in it that might otherwise be restricted or prohibited by law or by the terms of any such license or agreement, whether now existing or entered into in the future, and (y) Bank to have the ability in the event of a liquidation of any Collateral to dispose of such Collateral in accordance with Bank’s rights and remedies under this Agreement and the other Loan Documents.

5.3 Litigation . There are no actions or proceedings pending or, to the knowledge of the Responsible Officers, threatened in writing by or against Borrower or any of its Subsidiaries involving more than One Hundred Thousand Dollars ($100,000).

5.4 No Material Deviation in Financial Statements . All consolidated financial statements for Borrower and any of its Subsidiaries delivered to Bank fairly present in all material respects Borrower’s consolidated financial condition and Borrower’s consolidated results of operations as of the date of such financial statements. There has not been any material deterioration in Borrower’s consolidated financial condition since the date of the most recent financial statements submitted to Bank.

5.5 Solvency . The fair salable value of Borrower’s assets (including goodwill minus disposition costs) exceeds the fair value of its liabilities; Borrower is not left with unreasonably small capital after the transactions in this Agreement; and Borrower is able to pay its debts (including trade debts) as they mature.

5.6 Regulatory Compliance . Borrower is not an “investment company” or a company “controlled” by an “investment company” under the Investment Company Act. Borrower is not engaged as one of its important activities in extending credit for margin stock (under Regulations T and U of the Federal Reserve Board of Governors). Borrower has complied in all material respects with the Federal Fair Labor Standards Act. Neither Borrower nor any of its Subsidiaries is a “holding company” or an “affiliate” of a “holding company” or a “subsidiary company” of a “holding company” as each term is defined and used in the Public Utility Holding Company Act of 2005. Borrower has not violated any laws, ordinances or rules, the violation of which would reasonably be expected to have a material adverse effect on its business. None of Borrower’s or any of its Subsidiaries’ properties or assets has been used by Borrower or any Subsidiary or, to the best of Borrower’s knowledge, by previous Persons, in disposing, producing, storing, treating, or transporting any hazardous substance other than legally. Borrower and each of its Subsidiaries have obtained all consents, approvals and authorizations of, made all declarations or filings with, and given all notices to, all Government Authorities that are necessary to continue their respective businesses as currently conducted except where failure to do so would not reasonably be expected to have a material adverse effect on its business or operations.

5.7 Subsidiaries; Investments . Borrower does not own any stock, partnership interest or other equity securities except for Permitted Investments.

5.8 Tax Returns and Payments; Pension Contributions . Borrower has timely filed or obtained extensions for filing all required tax returns and reports, and Borrower has timely paid all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower. Borrower may defer payment of any contested taxes, provided that Borrower (a) in good faith contests its obligation to pay the taxes by appropriate proceedings promptly and diligently instituted and conducted, (b) notifies Bank in writing of the commencement of, and any material development in, the proceedings, (c) posts bonds or takes any other steps required to prevent the governmental authority levying such contested taxes from obtaining a Lien upon any of the Collateral that is other than a “Permitted Lien”. Borrower is unaware of any claims or adjustments proposed for any of Borrower’s prior tax years which could result in additional taxes becoming due and payable by Borrower. Borrower has paid all amounts necessary to fund all present pension, profit sharing and deferred compensation plans in accordance with their terms, and Borrower has not withdrawn from participation in, and has not permitted partial or complete termination of, or permitted the occurrence of any other event with respect to, any such plan which could reasonably be expected to result in any liability of Borrower, including any liability to the Pension Benefit Guaranty Corporation or its successors or any other governmental agency.

5.9 Use of Proceeds . Borrower shall use the proceeds of the Credit Extensions solely as working capital and to fund its general business requirements and not for personal, family, household or agricultural purposes.

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5.10 Full Disclosure . No written representation, warranty or other statement of Borrower in any certificate or written statement given to Bank, as of the date such representation, warranty, or other statement was made, taken together with all such written certificates and written statements given to Bank, contains any untrue statement of a material fact or omits to state a material fact necessary to make the statements contained in the certificates or statements not misleading in light of the circumstances under which they were made (it being recognized by Bank that the projections and forecasts provided by Borrower in good faith and based upon reasonable assumptions are not viewed as facts and that actual results during the period or periods covered by such projections and forecasts may differ from the projected or forecasted results).

AFFIRMATIVE COVENANTS

Borrower shall do all of the following:

6.1 Government Compliance.

(a) Maintain its and, except as provided in Section 7.3, all its Subsidiaries’ legal existence and good standing in their respective jurisdictions of formation and maintain qualification in each jurisdiction in which the failure to so qualify would reasonably be expected to have a material adverse effect on Borrower’s business or operations. Borrower shall comply, and have each Subsidiary comply, with all laws, ordinances and regulations to which it is subject, noncompliance with which could have a material adverse effect on Borrower’s business.

(b) Obtain all of the Governmental Approvals necessary for the performance by Borrower of its obligations under the Loan Documents to which it is a party and the grant of a security interest to Bank in all of its property. Borrower shall promptly upon request provide copies of any such obtained Governmental Approvals to Bank.

6.2 Financial Statements, Reports, Certificates . Deliver to Bank: (i) as soon as available, but no later than thirty (30) days after the last day of each month, a company prepared consolidated balance sheet and income statement covering Borrower’s consolidated operations for such month certified by a Responsible Officer and in a form acceptable to Bank; (ii) as soon as available, but no later than one hundred fifty (150) days after the last day of Borrower’s fiscal year, audited consolidated financial statements prepared under GAAP, consistently applied, together with an unqualified opinion on the financial statements from an independent certified public accounting firm acceptable to Bank in its reasonable discretion; (iii) within five (5) days of delivery, copies of all statements, reports and notices made generally available to Borrower’s security holders or to any holders of Subordinated Debt, (iv) in the event that Borrower becomes subject to the reporting requirements under the Securities Exchange Act of 1934, as amended, within five (5) days of filing, all reports on Form 10-K, 10-Q and 8-K filed with the Securities and Exchange Commission or a link thereto on Borrower’s or another website on the Internet; (v) a prompt report of any legal actions pending or threatened against Borrower or any of its Subsidiaries that could result in damages or costs to Borrower or any of its Subsidiaries of One Hundred Thousand Dollars ($100,000) or more; and (vi) budgets, sales projections, operating plans and other financial information reasonably requested by Bank.

6.3 Taxes; Pensions . Make, and cause each of its Subsidiaries to make, timely payment of all foreign, federal, state, and local taxes or assessments (other than taxes and assessments which Borrower is contesting pursuant to the terms of Section 5.8 hereof) and shall deliver to Bank, on demand, appropriate certificates attesting to such payments, and pay all amounts necessary to fund all present pension, profit sharing and deferred compensation plans in accordance with their terms.

6.4 Insurance . Keep its business and the Collateral insured for risks and in amounts standard for companies in Borrower’s industry and location as Bank may reasonably request. Insurance policies shall be in a form, with companies, and in amounts that are satisfactory to Bank. All property policies shall have a lender’s loss payable endorsement showing Bank as the sole lender loss payee and waive subrogation against Bank, and all liability policies shall show, or have endorsements showing, Bank as an additional insured. All policies (or the loss payable and additional insured endorsements) shall provide that the insurer shall endeavor to give Bank at least twenty (20) days notice before canceling, amending, or declining to renew its policy. At Bank’s request, Borrower shall deliver certified copies of policies and evidence of all premium payments. So long as no Event of Default has occurred and is continuing, Borrower shall have the option of applying the proceeds of any casualty policy toward

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the replacement or repair of destroyed or damaged property; provided that any such replaced or repaired property (i) shall be of equal or like value as the replaced or repaired Collateral and (ii) shall be deemed Collateral in which Bank has been granted a first priority security interest, and after the occurrence and during the continuance of an Event of Default, all proceeds payable under such casualty policy shall, at the option of Bank, be payable to Bank on account of the Obligations. If Borrower fails to obtain insurance as required under this Section 6.4 or to pay any amount or furnish any required proof of payment to third persons and Bank, Bank may make all or part of such payment or obtain such insurance policies required in this Section 6.4, and take any action under the policies Bank deems prudent.

6.5 Operating Accounts.

(a) Maintain a majority of its and its Subsidiaries’ primary operating and other deposit accounts and securities accounts with Bank and Bank’s Affiliates.

(b) Provide Bank five (5) days prior written notice before establishing any Collateral Account at or with any bank or financial institution other than Bank or Bank’s Affiliates. For each Collateral Account that Borrower at any time maintains, Borrower shall cause the applicable bank or financial institution (other than Bank) at or with which any Collateral Account is maintained to execute and deliver a Control Agreement or other appropriate instrument with respect to such Collateral Account to perfect Bank’s Lien in such Collateral Account in accordance with the terms hereunder. The provisions of the previous sentence shall not apply to deposit accounts exclusively used for payroll, payroll taxes and other employee wage and benefit payments to or for the benefit of Borrower’s employees and identified to Bank by Borrower as such.

6.6 Protection of Intellectual Property Rights . Borrower shall: (a) protect, defend and maintain the validity and enforceability of the intellectual property material to Borrower’s business; (b) promptly advise Bank in writing of material infringements of its intellectual property; and (c) not allow any intellectual property material to Borrower’s business to be abandoned, forfeited or dedicated to the public without Bank’s written consent.

6.7 Litigation Cooperation . From the date hereof and continuing through the termination of this Agreement, make available to Bank, without expense to Bank, Borrower and its officers, employees and agents and Borrower’s books and records, to the extent that Bank may deem them reasonably necessary to prosecute or defend any third-party suit or proceeding instituted by or against Bank with respect to any Collateral or relating to Borrower.

6.8 Warrants .

(a) At Closing, Borrower will issue Bank a Warrant to purchase up to 31,790 shares of its Series B Preferred Stock (the “ Initial Warrant ”), in the form attached hereto as Exhibit D , at a price per share equal to $2.43975.

(b) Thereafter, for every GC Line A Advance or GC Line B Advance that Bank makes to Borrower, Borrower will issue Bank an additional Warrant (each an “ Additional Warrant ” and together with the Initial Warrant, the “ Warrants ”), substantially in the same form as the Initial Warrant, for that number of shares of its Series B Preferred Stock, determined by multiplying the amount of Such GC Line A Advance or GC Line B Advance, as the case may be, by two percent (2.0%) and dividing such number by the most recent price per share at which the Series B Preferred Stock was sold by Borrower in an arms-length transaction, as may be adjusted for stock splits, dividends or the like. Each Additional Warrant shall be executed and delivered to Bank within ten (10) Business Days following such GC Line A Advance or GC Line B Advance.

6.9 Further Assurances . Execute any further instruments and take further action as Bank reasonably requests to perfect or continue Bank’s Lien in the Collateral or to effect the purposes of this Agreement.

NEGATIVE COVENANTS

Borrower shall not do any of the following without Bank’s prior written consent:

7.1 Dispositions . Convey, sell, lease, transfer or otherwise dispose of (collectively, “ Transfer ”), or permit any of its Subsidiaries to Transfer, all or any substantial part of its business or property, except (a) for

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Transfers of Inventory in the ordinary course of business; (b) for Transfers of worn-out, surplus or obsolete Equipment; (c) in connection with Permitted Liens and Permitted Investments; (d) for other Transfers which do not exceed One Hundred Thousand Dollars ($100,000) in any fiscal year, so long as an Event of Default does not exist at the time of such Transfer and would not exist after giving effect to such Transfer; and (f) for other Transfers contemplated by the exceptions to the covenants in Sections 7.7 or 7.8 .

7.2 Changes in Business, Management, Ownership, or Business Locations . (a) Engage in or permit any of its Subsidiaries to engage in any business other than the businesses currently engaged in by Borrower and such Subsidiary, as applicable, or reasonably related thereto; (b) liquidate or dissolve, except as to Subsidiaries, as permitted by Section 7.3; or (c) (i) have a change in its Chief Executive Officer, Chief Financial Officer or Chief Operating Officer (unless a replacement is approved by a majority of Borrower’s Board of Directors) or (ii) enter into any transaction or series of related transactions in which the stockholders of Borrower who were not stockholders immediately prior to the first such transaction own more than 50% of the voting stock of Borrower immediately after giving effect to such transaction or related series of such transactions (other than by the sale of Borrower’s equity securities in a public offering or to venture capital investors so long as Borrower identifies to Bank the venture capital investors prior to the closing of the transaction). Borrower shall not, without at least thirty (30) days prior written notice to Bank: (1) add any new offices or business locations, including warehouses (unless such new offices or business locations contain less than Fifty Thousand Dollars ($50,000) in Borrower’s assets or property), provided that Borrower may store raw materials and inventory at off-site locations without notice to Bank, (2) change its jurisdiction of organization, (3) change its organizational structure or type, (4) change its legal name, or (5) change any organizational number (if any) assigned by its jurisdiction of organization.

7.3 Mergers or Acquisitions . Merge or consolidate, or permit any of its Subsidiaries to merge or consolidate, with any other Person, or acquire, or permit any of its Subsidiaries to acquire, all or substantially all of the capital stock or property of another Person. A Subsidiary may merge or consolidate into another Subsidiary or into Borrower, except where (a) no Event of Default has occurred and is continuing or would result from such transaction, (b) such transaction would not result in a decrease of more than 25% of Borrower’s Tangible Net Worth, and (c) Borrower is the surviving entity.

7.4 Indebtedness . Create, incur, assume, or be liable for any Indebtedness, or permit any Subsidiary to do so, other than Permitted Indebtedness.

7.5 Encumbrance . Create, incur, allow, or suffer any Lien on any of its property, or assign or convey any right to receive income, including the sale of any Accounts, or permit any of its Subsidiaries to do so, except for Permitted Liens, permit any Collateral not to be subject to the first priority security interest granted herein, or enter into any agreement, document, instrument or other arrangement (except with or in favor of Bank) with any Person which directly or indirectly prohibits or has the effect of prohibiting Borrower or any Subsidiary from assigning, mortgaging, pledging, granting a security interest in or upon, or encumbering any of Borrower’s or any Subsidiary’s intellectual property, except as is otherwise permitted in Section 7.1 hereof and the definition of “Permitted Lien” herein.

7.6 Maintenance of Collateral Accounts . Maintain any Collateral Account except pursuant to the terms of Section 6.5(b) hereof.

7.7 Distributions; Investments . (a) Pay any dividends or make any distribution or payment or redeem, retire or purchase any capital stock, provided that (i) Borrower may convert any of its convertible securities into other securities pursuant to the terms of such convertible securities or otherwise in exchange therefor, (ii) Borrower may pay dividends solely in common stock, and (iii) Borrower may repurchase stock of former employees or consultants pursuant to stock repurchase agreements, in the aggregate in any fiscal year, so long as an Event of Default does not exist at the time of such repurchase and would not exist after giving effect to such repurchase; or (b) directly or indirectly make any Investment other than Permitted Investments, or permit any of its Subsidiaries to do so, except as permitted by Section 7.3.

7.8 Transactions with Affiliates . Directly or indirectly enter into or permit to exist any material transaction with any Affiliate of Borrower, except for (i) transactions that are in the ordinary course of Borrower’s business, upon fair and reasonable terms that are no less favorable to Borrower than would be obtained in an arm’s length transaction with a non-affiliated Person and (ii) transactions otherwise permitted pursuant to subsection (f) of the definition of Permitted Investments.

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7.9 Subordinated Debt . (a) Make or permit any payment on any Subordinated Debt, except under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank.

7.10 Compliance . Become an “investment company” or a company controlled by an “investment company”, under the Investment Company Act of 1940 or undertake as one of its important activities extending credit to purchase or carry margin stock (as defined in Regulation U of the Board of Governors of the Federal Reserve System), or use the proceeds of any Credit Extension for that purpose; fail to meet the minimum funding requirements of ERISA, permit a Reportable Event or Prohibited Transaction, as defined in ERISA, to occur; fail to comply with the Federal Fair Labor Standards Act or violate any other law or regulation, if the violation would reasonably be expected to have a material adverse effect on Borrower’s business, or permit any of its Subsidiaries to do so; withdraw or permit any Subsidiary to withdraw from participation in, permit partial or complete termination of, or permit the occurrence of any other event with respect to, any present pension, profit sharing and deferred compensation plan which would reasonably be expected to result in any liability of Borrower, including any liability to the Pension Benefit Guaranty Corporation or its successors or any other governmental agency.

EVENTS OF DEFAULT

Any one of the following shall constitute an event of default (an “ Event of Default ”) under this Agreement:

8.1 Payment Default . Borrower fails to (a) make any payment of principal or interest on any Credit Extension on its due date, or (b) pay any other Obligations within three (3) Business Days after such Obligations are due and payable (which three (3) day grace period shall not apply to payments due on the GC Line A Maturity Date or GC Line B Maturity Date). During the cure period, the failure to cure the payment default is not an Event of Default (but no Credit Extension will be made during the cure period);

8.2 Covenant Default .

(a) Borrower fails or neglects to perform any obligation in Sections 6.2, 6.3, 6.4, 6.5 or 6.8 or violates any covenant in Section 7; or

(b) Borrower fails or neglects to perform, keep, or observe any other term, provision, condition, covenant or agreement contained in this Agreement or any Loan Documents, and as to any default (other than those specified in this Section 8) under such other term, provision, condition, covenant or agreement that can be cured, has failed to cure the default within ten (10) days after the occurrence thereof; provided, however, that if the default cannot by its nature be cured within the ten (10) day period or cannot after diligent attempts by Borrower be cured within such ten (10) day period, and such default is likely to be cured within a reasonable time, then Borrower shall have an additional period (which shall not in any case exceed thirty (30) days) to attempt to cure such default, and within such reasonable time period the failure to cure the default shall not be deemed an Event of Default (but no Credit Extensions shall be made during such cure period). Grace periods provided under this section shall not apply, among other things, to financial covenants or any other covenants set forth in subsection (a) above;

8.3 Material Adverse Change . A Material Adverse Change occurs;

8.4 Attachment . (a) Any material portion of Borrower’s assets is attached, seized, levied on, or comes into possession of a trustee or receiver; (b) the service of process seeking to attach, by trustee or similar process, any funds of Borrower or of any entity under control of Borrower (including a Subsidiary) on deposit with Bank or any Bank Affiliate; (c) Borrower is enjoined, restrained, or prevented by court order from conducting any part of its business; or (d) a notice of lien, levy, or assessment is filed against any of Borrower’s assets by any government agency, and the same under clauses (a) through (d) hereof are not, within ten (10) days after the occurrence thereof, discharged or stayed (whether through the posting of a bond or otherwise); provided, however, no Credit Extensions shall be made during any ten (10) day cure period;

8.5 Insolvency (a) Borrower is unable to pay its debts (including trade debts) as they become due or otherwise becomes insolvent; (b) Borrower begins an Insolvency Proceeding; or (c) an Insolvency Proceeding is begun against Borrower and not dismissed or stayed within thirty (30) days (but no Credit Extensions shall be made while of any of the conditions described in clause (a) exist and/or until any Insolvency Proceeding is dismissed);

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8.6 Other Agreements . There is a default in any agreement to which Borrower is a party with a third party or parties resulting in a right by such third party or parties, whether or not exercised, to accelerate the maturity of any Indebtedness in an amount in excess of One Hundred Thousand Dollars ($100,000) or that could have a material adverse effect on Borrower’s business; provided, however, that the Event of Default under this Section 8.6 caused by the occurrence of a default under such other agreement shall be cured or waived for purposes of this Agreement upon Bank receiving written notice from the party asserting such default of such cure or waiver of the default under such other agreement, if at the time of such cure or waiver under such other agreement (a) Bank has not declared an Event of Default under this Agreement and/or exercised any rights with respect thereto; (b) any such cure or waiver does not result in an Event of Default under any other provision of this Agreement or any Loan Document; and (c) in connection with any such cure or waiver under such other agreement, the terms of any agreement with such third party are not modified or amended in any manner which could in the good faith judgment of Bank be materially less advantageous to Borrower;

8.7 Judgments . One or more judgments, orders, or decrees for the payment of money in an amount, individually or in the aggregate, of at least One Hundred Thousand Dollars ($100,000) (not covered by independent third-party insurance as to which liability has been accepted by such insurance carrier) shall be rendered against Borrower and shall remain unsatisfied, unvacated, or unstayed for a period of ten (10) days after the entry thereof (provided that no Credit Extensions will be made prior to the satisfaction, vacation, or stay of such judgment, order, or decree);

8.8 Misrepresentations . Borrower or any Person acting for Borrower makes any representation, warranty, or other statement now or later in this Agreement, any Loan Document or in any writing delivered to Bank or to induce Bank to enter this Agreement or any Loan Document, and such representation, warranty, or other statement is incorrect in any material respect when made;

8.9 Subordinated Debt . A default or breach occurs under any agreement between Borrower and any creditor of Borrower that signed a subordination, intercreditor, or other similar agreement with Bank, or any creditor that has signed such an agreement with Bank breaches any terms of such agreement; or

8.11 Governmental Approvals. Any Governmental Approval shall have been (a) revoked, rescinded, suspended, modified in an adverse manner or not renewed in the ordinary course for a full term or (b) subject to any decision by a Governmental Authority that designates a hearing with respect to any applications for renewal of any of such Governmental Approval or that could result in the Governmental Authority taking any of the actions described in clause (a) above, and such decision or such revocation, rescission, suspension, modification or non-renewal (i) has, or could reasonably be expected to have, a Material Adverse Change, or (ii) adversely affects the legal qualifications of Borrower or any of its Subsidiaries to hold such Governmental Approval in any applicable jurisdiction and such revocation, rescission, suspension, modification or non-renewal could reasonably be expected to affect the status of or legal qualifications of Borrower or any of its Subsidiaries to hold any Governmental Approval in any other jurisdiction.

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BANK’S RIGHTS AND REMEDIES

9.1 Rights and Remedies . While an Event of Default occurs and continues Bank may, without notice or demand, do any or all of the following:

(a) declare all Obligations immediately due and payable (but if an Event of Default described in Section 8.5 occurs all Obligations are immediately due and payable without any action by Bank);

(b) stop advancing money or extending credit for Borrower’s benefit under this Agreement or under any other agreement between Borrower and Bank;

(c) settle or adjust disputes and claims directly with Account Debtors for amounts on terms and in any order that Bank considers advisable, notify any Person owing Borrower money of Bank’s security interest in such funds, and verify the amount of such account;

(d) make any payments and do any acts it considers necessary or reasonable to protect the Collateral and/or its security interest in the Collateral. Borrower shall assemble the Collateral if Bank requests and make it available as Bank designates. Bank may enter premises where the Collateral is located, take and maintain possession of any part of the Collateral, and pay, purchase, contest, or compromise any Lien which appears to be prior or superior to its security interest and pay all expenses incurred. Borrower grants Bank a license to enter and occupy any of its premises, without charge, to exercise any of Bank’s rights or remedies;

(e) apply to the Obligations any (i) balances and deposits of Borrower it holds, or (ii) any amount held by Bank owing to or for the credit or the account of Borrower;

(f) ship, reclaim, recover, store, finish, maintain, repair, prepare for sale, advertise for sale, and sell the Collateral. Bank is hereby granted a non-exclusive, royalty-free license or other right to use without charge, Borrower’s labels, patents, copyrights, mask works, rights of use of any name, trade secrets, trade names, trademarks, service marks, and advertising matter, or any similar property as it pertains to the Collateral, in completing production of, advertising for sale, and selling any Collateral and, in connection with Bank’s exercise of its rights under this Section, Borrower’s rights under all licenses and all franchise agreements inure to Bank’s benefit;

(g) place a “hold” on any account maintained with Bank and/or deliver a notice of exclusive control, any entitlement order, or other directions or instructions pursuant to any Control Agreement or similar agreements providing control of any Collateral (and Bank agrees not to deliver such notice, order, directions or instructions unless an Event of Default has occurred and is continuing);

(h) demand and receive possession of Borrower’s Books; and

(i) exercise all rights and remedies available to Bank under the Loan Documents or at law or equity, including all remedies provided under the Code (including disposal of the Collateral pursuant to the terms thereof).

9.2 Power of Attorney . Borrower hereby irrevocably appoints Bank as its lawful attorney-in-fact, exercisable upon the occurrence and during the continuance of an Event of Default, to: (a) endorse Borrower’s name on any checks or other forms of payment or security; (b) sign Borrower’s name on any invoice or bill of lading for any Account or drafts against Account Debtors; (c) settle and adjust disputes and claims about the Accounts directly with Account Debtors, for amounts and on terms Bank determines reasonable; (d) make, settle, and adjust all claims under Borrower’s insurance policies; (e) pay, contest or settle any Lien, charge, encumbrance, security interest, and adverse claim in or to the Collateral, or any judgment based thereon, or otherwise take any action to terminate or discharge the same; and (f) transfer the Collateral into the name of Bank or a third party as the Code permits. Borrower hereby appoints Bank as its lawful attorney-in-fact to sign Borrower’s name on any documents necessary to perfect or continue the perfection of Bank’s security interest in the Collateral regardless of whether an Event of Default has occurred until all Obligations (other than those arising under the Warrants and inchoate indemnity obligations) have been satisfied in full and Bank is under no further obligation to make Credit Extensions hereunder. Bank’s foregoing appointment as Borrower’s attorney in fact, and all of Bank’s rights and powers, coupled with an interest, are irrevocable until all Obligations (other than those arising under the Warrants and inchoate indemnity obligations) have been fully repaid and performed and Bank’s obligation to provide Credit Extensions terminates.

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9.3 Protective Payments . If Borrower fails to obtain the insurance called for by Section 6.5 or fails to pay any premium thereon or fails to pay any other amount which Borrower is obligated to pay under this Agreement or any other Loan Document, Bank may obtain such insurance or make such payment, and all amounts so paid by Bank are Bank Expenses and immediately due and payable, bearing interest at the then highest applicable rate, and secured by the Collateral. Bank will make reasonable efforts to provide Borrower with notice of Bank obtaining such insurance or making such payment at the time it is obtained or within a reasonable time thereafter. No payments by Bank are deemed an agreement to make similar payments in the future or Bank’s waiver of any Event of Default.

9.4 Application of Payments and Proceeds . Borrower shall have no right to specify the order or the accounts to which Bank shall allocate or apply any payments required to be made by Borrower to Bank or otherwise received by Bank under this Agreement when any such allocation or application is not specified elsewhere in this Agreement. If an Event of Default has occurred and is continuing, Bank may apply any funds in its possession, whether from Borrower account balances, payments, proceeds realized as the result of any collection of Accounts or other disposition of the Collateral, or otherwise, to the Obligations in such order as Bank shall determine in its sole discretion. Any surplus shall be paid to Borrower or other Persons legally entitled thereto; Borrower shall remain liable to Bank for any deficiency. If Bank, in its good faith business judgment, directly or indirectly enters into a deferred payment or other credit transaction with any purchaser at any sale of Collateral, Bank shall have the option, exercisable at any time, of either reducing the Obligations by the principal amount of the purchase price or deferring the reduction of the Obligations until the actual receipt by Bank of cash therefor.

9.5 Bank’s Liability for Collateral . So long as Bank complies with reasonable banking practices regarding the safekeeping of the Collateral in the possession or under the control of Bank, Bank shall not be liable or responsible for: (a) the safekeeping of the Collateral; (b) any loss or damage to the Collateral; (c) any diminution in the value of the Collateral; or (d) any act or default of any carrier, warehouseman, bailee, or other Person. Borrower bears all risk of loss, damage or destruction of the Collateral.

9.6 No Waiver; Remedies Cumulative . Bank’s failure, at any time or times, to require strict performance by Borrower of any provision of this Agreement or any other Loan Document shall not waive, affect, or diminish any right of Bank thereafter to demand strict performance and compliance herewith or therewith. No waiver hereunder shall be effective unless signed by Bank and then is only effective for the specific instance and purpose for which it is given. Bank’s rights and remedies under this Agreement and the other Loan Documents are cumulative. Bank has all rights and remedies provided under the Code, by law, or in equity. Bank’s exercise of one right or remedy is not an election, and Bank’s waiver of any Event of Default is not a continuing waiver. Bank’s delay in exercising any remedy is not a waiver, election, or acquiescence.

9.7 Demand Waiver . Borrower waives demand, notice of default or dishonor, notice of payment and nonpayment, notice of any default, nonpayment at maturity, release, compromise, settlement, extension, or renewal of accounts, documents, instruments, chattel paper, and guarantees held by Bank on which Borrower is liable.

NOTICES

All notices, consents, requests, approvals, demands, or other communication (collectively, “ Communication ”) by any party to this Agreement or any other Loan Document must be in writing and shall be deemed to have been validly served, given, or delivered: (a) upon the earlier of actual receipt and three (3) Business Days after deposit in the U.S. mail, first class, registered or certified mail return receipt requested, with proper postage prepaid; (b) upon transmission, when sent by electronic mail or facsimile transmission; (c) one (1) Business Day after deposit with a reputable overnight courier with all charges prepaid; or (d) when delivered, if hand-delivered by messenger, all of which shall be addressed to the party to be notified and sent to the address, facsimile number, or email address indicated below. Bank or Borrower may change its address or facsimile number by giving the other party written notice thereof in accordance with the terms of this Section 10.

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If to Borrower:	ARCA Discovery, Inc.
	1200 17th St., Suite 620
	Denver, CO 80202
	Attn:	Patrick Wheeler
	Fax:	303-825-0883
	Email:	Pat.Wheeler@arcadiscovery.com

If to Bank:	Silicon Valley Bank
	380 Interlocken Crescent, Suite 600
	Broomfield, CO 80021
	Attn:	Adam Glick
	Fax:	303-469-9088
	Email:	aglick@svb.com

CHOICE OF LAW, VENUE, JURY TRIAL WAIVER AND JUDICIAL REFERENCE

California law governs the Loan Documents other than the Warrants without regard to principles of conflicts of law. Borrower and Bank each submit to the exclusive jurisdiction of the State and Federal courts in Santa Clara County, California; provided, however, that nothing in this Agreement shall be deemed to operate to preclude Bank from bringing suit or taking other legal action in any other jurisdiction to realize on the Collateral or any other security for the Obligations, or to enforce a judgment or other court order in favor of Bank. Borrower expressly submits and consents in advance to such jurisdiction in any action or suit commenced in any such court, and Borrower hereby waives any objection that it may have based upon lack of personal jurisdiction, improper venue, or forum non conveniens and hereby consents to the granting of such legal or equitable relief as is deemed appropriate by such court. Borrower hereby waives personal service of the summons, complaints, and other process issued in such action or suit and agrees that service of such summons, complaints, and other process may be made by registered or certified mail addressed to Borrower at the address set forth in Section 10 of this Agreement and that service so made shall be deemed completed upon the earlier to occur of Borrower’s actual receipt thereof or three (3) days after deposit in the U.S. mails, proper postage prepaid.

TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, BORROWER AND BANK EACH WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION ARISING OUT OF OR BASED UPON THIS AGREEMENT, THE LOAN DOCUMENTS OR ANY CONTEMPLATED TRANSACTION, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL OTHER CLAIMS. THIS WAIVER IS A MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS AGREEMENT. EACH PARTY HAS REVIEWED THIS WAIVER WITH ITS COUNSEL .

WITHOUT INTENDING IN ANY WAY TO LIMIT THE PARTIES’ AGREEMENT TO WAIVE THEIR RESPECTIVE RIGHT TO A TRIAL BY JURY, if the above waiver of the right to a trial by jury is not enforceable, the parties hereto agree that any and all disputes or controversies of any nature between them arising at any time shall be decided by a reference to a private judge, mutually selected by the parties (or, if they cannot agree, by the Presiding Judge of the Santa Clara County, California Superior Court) appointed in accordance with California Code of Civil Procedure Section 638 (or pursuant to comparable provisions of federal law if the dispute falls within the exclusive jurisdiction of the federal courts), sitting without a jury, in Santa Clara County, California; and the parties hereby submit to the jurisdiction of such court. The reference proceedings shall be conducted pursuant to and in accordance with the provisions of California Code of Civil Procedure §§ 638 through 645.1, inclusive. The private judge shall have the power, among others, to grant provisional relief, including without limitation, entering temporary restraining orders, issuing preliminary and permanent injunctions and appointing receivers. All such proceedings shall be closed to the public and confidential and all records relating thereto shall be permanently sealed. If during the course of any dispute, a party desires to seek provisional relief, but a judge has not been appointed at that point pursuant to the judicial reference procedures, then such party may apply to the Santa Clara County, California Superior Court for such relief. The proceeding before the private judge shall be conducted in the same manner as it would be before a court under the rules of evidence applicable to judicial proceedings. The parties shall be entitled to discovery which shall be conducted in the same manner as it would be before a court under the rules of discovery applicable to judicial proceedings. The private judge shall oversee discovery and may enforce all discovery rules and order applicable to judicial proceedings in the same manner as a trial court judge. The parties agree that the selected or appointed private judge shall have the power to decide all issues in the action or proceeding, whether of fact or of law, and shall report a statement of decision thereon pursuant to the California

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Code of Civil Procedure § 644(a). Nothing in this paragraph shall limit the right of any party at any time to exercise self-help remedies, foreclose against collateral, or obtain provisional remedies. The private judge shall also determine all issues relating to the applicability, interpretation, and enforceability of this paragraph.

GENERAL PROVISIONS

12.1 Successors and Assigns . This Agreement binds and is for the benefit of the successors and permitted assigns of each party. Borrower may not assign this Agreement or any rights or obligations under it without Bank’s prior written consent (which may be granted or withheld in Bank’s discretion). Bank has the right, without the consent of or notice to Borrower, to sell, transfer, negotiate, or grant participation in all or any part of, or any interest in, Bank’s obligations, rights, and benefits under this Agreement and the other Loan Documents.

12.2 Indemnification . Borrower agrees to indemnify, defend and hold Bank and its directors, officers, employees, agents, attorneys, or any other Person affiliated with or representing Bank harmless against: (a) all obligations, demands, claims, and liabilities (collectively, “ Claims ”) asserted by any other party in connection with the transactions contemplated by the Loan Documents; and (b) all losses or Bank Expenses incurred, or paid by Bank from, following, or arising from transactions between Bank and Borrower (including reasonable attorneys’ fees and expenses), except, as to (a) and (b), for Claims and/or losses directly caused by Bank’s gross negligence or willful misconduct.

12.3 Time of Essence . Time is of the essence for the performance of all Obligations in this Agreement.

12.4 Severability of Provisions . Each provision of this Agreement is severable from every other provision in determining the enforceability of any provision.

12.5 Amendments in Writing; Integration . All amendments to this Agreement must be in writing and signed by both Bank and Borrower. This Agreement and the Loan Documents represent the entire agreement about this subject matter and supersede prior negotiations or agreements. All prior agreements, understandings, representations, warranties, and negotiations between the parties about the subject matter of this Agreement and the Loan Documents merge into this Agreement and the Loan Documents.

12.6 Counterparts . This Agreement may be executed in any number of counterparts and by different parties on separate counterparts, each of which, when executed and delivered, are an original, and all taken together, constitute one Agreement.

12.7 Survival . All covenants, representations and warranties made in this Agreement continue in full force until this Agreement has terminated pursuant to its terms and all Obligations (other than those arising under the Warrants and inchoate indemnity obligations and any other obligations which, by their terms, are to survive the termination of this Agreement) have been satisfied. The obligation of Borrower in Section 12.2 to indemnify Bank shall survive until the statute of limitations with respect to such claim or cause of action shall have run.

12.8 Confidentiality . In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain such prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; and (e) as Bank considers appropriate in exercising remedies under this Agreement. Confidential information does not include information that either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank through no fault of Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

12.9 Attorneys’ Fees, Costs and Expenses . In any action or proceeding between Borrower and Bank arising out of or relating to the Loan Documents, the prevailing party shall be entitled to recover its reasonable attorneys’ fees and other costs and expenses incurred, in addition to any other relief to which it may be entitled.

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DEFINITIONS

13.1 Definitions . As used in this Agreement, the following terms have the following meanings:

“ Account ” is any “account” as defined in the Code with such additions to such term as may hereafter be made, and includes, without limitation, all accounts receivable and other sums owing to Borrower.

“ Account Debtor ” is any “account debtor” as defined in the Code with such additions to such term as may hereafter be made.

“ Additional Warrant ” is defined in Section 6.8(c).

“ Affiliate ” of any Person is a Person that owns or controls directly or indirectly the Person, any Person that controls or is controlled by or is under common control with the Person, and each of that Person’s senior executive officers, directors, partners and, for any Person that is a limited liability company, that Person’s managers and members.

“ Agreement ” is defined in the preamble hereof.

“ Bank ” is defined in the preamble hereof.

“ Bank Expenses ” are all audit fees and expenses, costs, and expenses (including reasonable attorneys’ fees and expenses) for preparing, amending, negotiating, administering, defending and enforcing the Loan Documents (including, without limitation, those incurred in connection with appeals or Insolvency Proceedings) or otherwise incurred with respect to Borrower.

“ Borrower ” is defined in the preamble hereof

“ Borrower’s Books ” are all Borrower’s books and records including ledgers, federal and state tax returns, records regarding Borrower’s assets or liabilities, the Collateral, business operations or financial condition, and all computer programs or storage or any equipment containing such information.

“ Business Day ” is any day that is not a Saturday, Sunday or a day on which Bank is closed.

“Cash Equivalents” means (a) marketable direct obligations issued or unconditionally guaranteed by the United States or any agency or any State thereof having maturities of not more than one (1) year from the date of acquisition; (b) commercial paper maturing no more than one (1) year after its creation and having the highest rating from either Standard & Poor’s Ratings Group or Moody’s Investors Service, Inc.; (c) Bank’s certificates of deposit issued maturing no more than one (1) year after issue; and (d) money market funds at least ninety-five percent (95%) of the assets of which constitute Cash Equivalents of the kinds described in clauses (a) through (c) of this definition.

“ Change of Control ” means (a) any event, transaction, or occurrence as a result of which any “person” (as such term is defined in Sections 3(a)(9) and 13(d)(3) of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”)), other than a trustee or other fiduciary holding securities under an employee benefit plan of Borrower, is or becomes a beneficial owner (within the meaning Rule 13d-3 promulgated under the Exchange Act), directly or indirectly, of securities of Borrower, representing more than fifty percent (50%) of the combined voting power of Borrower’s then outstanding securities (other than by the sale of Borrower’s equity securities to venture capital investors so long as Borrower identifies to Bank the venture capital investors prior to the closing of the transaction) or (b) if Borrower sells all, or substantially all, of its assets in one transaction or a series of related transactions.

“ Code ” is the Uniform Commercial Code, as the same may, from time to time, be enacted and in effect in the State of California; provided, that, to the extent that the Code is used to define any term herein or in any Loan Document and such term is defined differently in different Articles or Divisions of the Code, the definition of such term contained in Article or Division 9 shall govern; provided further, that in the event that, by reason of mandatory provisions of law, any or all of the attachment, perfection, or priority of, or remedies with respect to, Bank’s Lien on any Collateral is governed by the Uniform Commercial Code in effect in a jurisdiction other than the State of California, the term “ Code ” shall mean the Uniform Commercial Code as enacted and in effect in such other jurisdiction solely for purposes on the provisions thereof relating to such attachment, perfection, priority, or remedies and for purposes of definitions relating to such provisions.

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“ Collateral ” is any and all properties, rights and assets of Borrower described on Exhibit A .

“ Collateral Account ” is any Deposit Account, Securities Account, or Commodity Account.

“ Commodity Account ” is any “commodity account” as defined in the Code with such additions to such term as may hereafter be made.

“ Communication ” is defined in Section 10.

“ Contingent Obligation ” is, for any Person, any direct or indirect liability, contingent or not, of that Person for (a) any indebtedness, lease, dividend, letter of credit or other obligation of another such as an obligation directly or indirectly guaranteed, endorsed, co-made, discounted or sold with recourse by that Person, or for which that Person is directly or indirectly liable; (b) any obligations for undrawn letters of credit for the account of that Person; and (c) all obligations from any interest rate, currency or commodity swap agreement, interest rate cap or collar agreement, or other agreement or arrangement designated to protect a Person against fluctuation in interest rates, currency exchange rates or commodity prices; but “Contingent Obligation” does not include endorsements in the ordinary course of business. The amount of a Contingent Obligation is the stated or determined amount of the primary obligation for which the Contingent Obligation is made or, if not determinable, the maximum reasonably anticipated liability for it determined by the Person in good faith; but the amount may not exceed the maximum of the obligations under any guarantee or other support arrangement.

“ Control Agreement ” is any control agreement entered into among the depository institution at which Borrower maintains a Deposit Account or the securities intermediary or commodity intermediary at which Borrower maintains a Securities Account or a Commodity Account, Borrower, and Bank pursuant to which Bank obtains control (within the meaning of the Code) over such Deposit Account, Securities Account, or Commodity Account.

“ Corporate Borrowing Certificate ” is attached hereto as Exhibit C .

“ Credit Extension ” is any GC Line A Advance, GC Line B Advance, or any other extension of credit by Bank for Borrower’s benefit.

“ Default Rate ” is defined in Section 2.2(b).

“ Deposit Account ” is any “deposit account” as defined in the Code with such additions to such term as may hereafter be made.

“ Designated Deposit Account ” is Borrower’s deposit account, account number 3300445283, maintained with Bank.

“ Dollars ,” “ dollars ” and “ $ ” each mean lawful money of the United States.

“ Effective Date ” is the date Bank executes this Agreement as indicated on the signature page hereof.

“ Equipment ” is all “equipment” as defined in the Code with such additions to such term as may hereafter be made, and includes without limitation all machinery, fixtures, goods, vehicles (including motor vehicles and trailers), and any interest in any of the foregoing.

“ ERISA ” is the Employee Retirement Income Security Act of 1974, and its regulations.

“ Event of Default ” is defined in Section 8.

“ Funding Date ” is any date on which a Credit Extension is made to or on account of Borrower which shall be a Business Day.

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“ GAAP ” is generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other Person as may be approved by a significant segment of the accounting profession, which are applicable to the circumstances as of the date of determination.

“ GC Line A Advance ” is defined in Section 2.1.1(a).

“ GC Line A Tranche One Amortization Start Date ” and “ GC Line A Tranche Two Amortization Start Date ” are defined in Section 2.1.1(b).

“ GC Line A Draw Period ” is the period of time from the Effective Date through June 30, 2008 (unless terminated earlier in accordance with Section 9).

“ GC Line A Tranche One Maturity Date ” is the date which is twenty-nine (29) months following the GC Line A Tranche One Amortization Start Date.

“ GC Line A Tranche Two Maturity Date ” is December 1, 2010.

“ GC Line B Advance ” is defined in Section 2.1.2(a).

“ GC Line B Tranche One Amortization Start Date ” and “ GC Line B Tranche Two Amortization Start Date ” are defined in Section 2.1.2(b).

“ GC Line B Draw Period ” is the period of time from the Milestone Achievement Date through December 31, 2008 (unless terminated earlier in accordance with Section 9).

“ GC Line B Tranche One Maturity Date ” is the date which is twenty-three (23) months following the GC Line B Tranche One Amortization Start Date.

“ GC Line B Tranche Two Maturity Date ” is December 1, 2010.

“ General Intangibles ” is all “general intangibles” as defined in the Code in effect on the date hereof with such additions to such term as may hereafter be made, and includes without limitation, all copyright rights, copyright applications, copyright registrations and like protections in each work of authorship and derivative work, whether published or unpublished, any patents, trademarks, service marks and, to the extent permitted under applicable law, any applications therefor, whether registered or not, any trade secret rights, including any rights to unpatented inventions, payment intangibles, royalties, contract rights, goodwill, franchise agreements, purchase orders, customer lists, route lists, telephone numbers, domain names, claims, income and other tax refunds, security and other deposits, options to purchase or sell real or personal property, rights in all litigation presently or hereafter pending (whether in contract, tort or otherwise), insurance policies (including without limitation key man, property damage, and business interruption insurance), payments of insurance and rights to payment of any kind.

“ Governmental Approval ” is any consent, authorization, approval, order, license, franchise, permit, certificate, accreditation, registration, filing or notice, of, issued by, from or to, or other act by or in respect of, any Governmental Authority.

“ Governmental Authority ” is any nation or government, any state or other political subdivision thereof, any agency, authority, instrumentality, regulatory body, court, central bank or other entity exercising executive, legislative, judicial, taxing, regulatory or administrative functions of or pertaining to government, any securities exchange and any self-regulatory organization.

“ Growth Capital Line A ” is a GC Line A Advance or GC Line A Advances in an aggregate amount of up to Two Million Dollars ($2,000,000).

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“ Growth Capital Line B ” is a GC Line B Advance or GC Line B Advances in an aggregate amount of up to Two Million Dollars ($2,000,000), plus any amounts from Growth Capital Line A that may be added to such amount pursuant to Section 2.1.1(a) of this Agreement.

“ Indebtedness ” is (a) indebtedness for borrowed money or the deferred price of property or services, such as reimbursement and other obligations for surety bonds and letters of credit, (b) obligations evidenced by notes, bonds, debentures or similar instruments, (c) capital lease obligations, and (d) Contingent Obligations.

“ Initial Warrant ” is defined in Section 6.8(a).

“ Insolvency Proceeding ” is any proceeding by or against any Person under the United States Bankruptcy Code, or any other bankruptcy or insolvency law, including assignments for the benefit of creditors, compositions, extensions generally with its creditors, or proceedings seeking reorganization, arrangement, or other relief.

“ Inventory ” is all “inventory” as defined in the Code in effect on the date hereof with such additions to such term as may hereafter be made, and includes without limitation all merchandise, raw materials, parts, supplies, packing and shipping materials, work in process and finished products, including without limitation such inventory as is temporarily out of Borrower’s custody or possession or in transit and including any returned goods and any documents of title representing any of the above.

“ Investment ” is any beneficial ownership interest in any Person (including stock, partnership interest or other securities), and any loan, advance or capital contribution to any Person.

“ Issue Price ” is defined in Section 6.8(a).

“ Lien ” is a claim, mortgage, deed of trust, levy, charge, pledge, security interest or other encumbrance of any kind, whether voluntarily incurred or arising by operation of law or otherwise against any property.

“ Loan Documents ” are, collectively, this Agreement, the Initial Warrant, each Additional Warrant, the Perfection Certificate, any note, or notes or guaranties executed by Borrower or any guarantor, and any other present or future agreement between Borrower any guarantor and/or for the benefit of Bank in connection with this Agreement, all as amended, restated, or otherwise modified.

“ Material Adverse Change ” is (a) a material impairment in the perfection or priority of Bank’s Lien in the Collateral or in the value of such Collateral; (b) a material adverse change in the business, operations, or condition (financial or otherwise) of Borrower; or (c) a material impairment of the prospect of repayment of any portion of the Obligations.

“ Milestone Achievement Date ” means the date on which Borrower has (a) received a fully-executed term sheet for no less than $17,500,000 in new equity financing (not including convertible debt) from investors acceptable to Bank and (b) filed, at a minimum, the clinical data section of an Application to Market a New Drug, Biologic or an Antibiotic Drug for Human Use (FDA Form 356H) with the U.S. Food and Drug Administration for the pharmaceutical being developed by Borrower commonly known as “Bucindolol”.

“ Obligations ” are Borrower’s obligation to pay when due any debts, principal, interest, Bank Expenses and other amounts Borrower owes Bank now or later, whether under this Agreement, the Loan Documents, or otherwise, including, without limitation, all obligations relating to letters of credit (including reimbursement obligations for drawn and undrawn letters of credit), cash management services, and foreign exchange contracts, if any, and including interest accruing after Insolvency Proceedings begin and debts, liabilities, or obligations of Borrower assigned to Bank, and the performance of Borrower’s duties under the Loan Documents.

“ Payment/Advance Form ” is that certain form attached hereto as Exhibit B .

“ Perfection Certificate ” is defined in Section 5.1.

“ Permitted Indebtedness ” is:

(a) Borrower’s Indebtedness to Bank under this Agreement and the other Loan Documents;

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(b) Indebtedness existing on the Effective Date and shown on the Perfection Certificate;

(d) unsecured Indebtedness to trade creditors incurred in the ordinary course of business;

(e) Indebtedness incurred as a result of endorsing negotiable instruments received in the ordinary course of business;

(f) Indebtedness secured by Permitted Liens;

(g) Other unsecured Indebtedness not exceeding Fifty Thousand Dollars ($50,000) in the aggregate outstanding at any time; provided , however, that, at the time such Indebtedness is incurred, no Event of Default has occurred, is continuing or would result from such Indebtedness; and

(h) extensions, refinancings, modifications, amendments and restatements of any items of Permitted Indebtedness (a) through (g) above, provided that the principal amount thereof is not increased or the terms thereof are not modified to impose more burdensome terms upon Borrower or its Subsidiary, as the case may be.

“ Permitted Investments ” are:

(a) Investments shown on the Perfection Certificate and existing on the Effective Date;

(b) Cash Equivalents and any Investments permitted by Borrower’s investment policy, as amended from time to time, provided that such investment policy (and any such amendment thereto) has been approved by Bank;

(c) Investments consisting of the endorsement of negotiable instruments for deposit or collection or similar transactions in the ordinary course of Borrower;

(d) Investments consisting of deposit accounts in which Bank has a perfected security interest;

(e) Investments accepted in connection with Transfers permitted by Section 7.1;

(f) Investments consisting of (i) travel advances and employee relocation loans and other employee loans and advances in the ordinary course of business, and (ii) loans to employees, officers or directors relating to the purchase of equity securities of Borrower or its Subsidiaries pursuant to employee stock purchase plans or agreements approved by Borrower’s Board of Directors;

(g) Investments (including debt obligations) received in connection with the bankruptcy or reorganization of customers or suppliers and in settlement of delinquent obligations of, and other disputes with, customers or suppliers arising in the ordinary course of business;

(h) Investments consisting of notes receivable of, or prepaid royalties and other credit extensions, to customers and suppliers who are not Affiliates, in the ordinary course of business; provided that this paragraph (h) shall not apply to Investments of Borrower in any Subsidiary;

(i) Investments in joint ventures, strategic alliances, licensing and similar arrangements customary in Borrower’s industry and which do not require Borrower to assume or otherwise become liable for the obligations of any third party not directly related to or arising out of such arrangement or transfer ownership of non-cash assets to such joint venture or other entity; and

(j) other Investments not otherwise permitted by Section 7.7 not exceeding $50,000 in the aggregate outstanding at any time; provided , however, that, at the time such Investment is made, no Event of Default has occurred, is continuing or would result from such Investment.

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“ Permitted Liens ” are:

(a) Liens existing on the Effective Date and shown on the Perfection Certificate or arising under this Agreement and the other Loan Documents;

(b) Liens for taxes, fees, assessments or other government charges or levies, either not delinquent or being contested in good faith and for which Borrower maintains adequate reserves on its Books, provided that no notice of any such Lien has been filed or recorded under the Internal Revenue Code of 1986, as amended, and the Treasury Regulations adopted thereunder;

(c) purchase money Liens (including capital leases) (i) on Equipment acquired or held by Borrower incurred for financing the acquisition of the Equipment securing no more than $500,000 in the aggregate amount outstanding, or (ii) existing on Equipment when acquired, if the Lien is confined to the property and improvements and the proceeds of the Equipment;

(d) Liens of carriers, warehousemen, suppliers, or other Persons that are possessory in nature arising in the ordinary course of business, and which are not delinquent or remain payable without penalty or which are being contested in good faith and by appropriate proceedings which proceedings have the effect of preventing the forfeiture or sale of the property subject thereto;

(e) Liens to secure payment of workers’ compensation, employment insurance, old-age pensions, social security and other like obligations incurred in the ordinary course of business (other than Liens imposed by ERISA);

(f) leases or subleases of real property granted in the ordinary course of business, and leases, subleases, non-exclusive licenses or sublicenses of property (other than real property or intellectual property) granted in the ordinary course of Borrower’s business, if the leases, subleases, licenses and sublicenses do not prohibit granting Bank a security interest;

(g) non-exclusive licenses of intellectual property granted to third parties in the ordinary course of business and the rights of licensors under licenses of intellectual property to Borrower or its Subsidiaries entered into the ordinary course of business;

(h) Liens arising from attachments or judgments, orders, or decrees in circumstances not constituting an Event of Default under Sections 8.4 and 8.7;

(i) Liens in favor of other financial institutions arising in connection with Borrower’s deposit and/or securities accounts held at such institutions, provided that Bank has a perfected security interest in the amounts held in such deposit and/or securities accounts;

(j) bankers’ liens, rights of setoff and similar Liens incurred on deposits made in the ordinary course of business; and

(k) Liens incurred in the extension, renewal or refinancing of the indebtedness secured by Liens described in (a) through (j), but any extension, renewal or replacement Lien must be limited to the property encumbered by the existing Lien and the principal amount of the indebtedness may not increase.

“ Person ” is any individual, sole proprietorship, partnership, limited liability company, joint venture, company, trust, unincorporated organization, association, corporation, institution, public benefit corporation, firm, joint stock company, estate, entity or government agency.

“ Prime Rate ” is Bank’s most recently announced “prime rate,” even if it is not Bank’s lowest rate.

“ Registered Organization ” is any “registered organization” as defined in the Code with such additions to such term as may hereafter be made

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“ Requirement of Law ” is as to any Person, the organizational or governing documents of such Person, and any law (statutory or common), treaty, rule or regulation or determination of an arbitrator or a court or other Governmental Authority, in each case applicable to or binding upon such Person or any of its property or to which such Person or any of its property is subject.

“ Responsible Officer ” is any of the Chief Executive Officer, President, Chief Financial Officer and Controller of Borrower.

“ Securities Account ” is any “securities account” as defined in the Code with such additions to such term as may hereafter be made.

“ Series A Price ” is defined in Section 6.8(b).

“ Series B Round ” is defined in Section 6.8(a).

“ Subordinated Debt ” is indebtedness incurred by Borrower subordinated to all of Borrower’s now or hereafter indebtedness to Bank (pursuant to a subordination, intercreditor, or other similar agreement in form and substance satisfactory to Bank entered into between Bank and the other creditor), on terms acceptable to Bank.

“ Subsidiary ” means, with respect to any Person, any Person of which more than 50.0% of the voting stock or other equity interests (in the case of Persons other than corporations) is owned or controlled directly or indirectly by such Person or one or more of Affiliates of such Person. A “Subsidiary” without further attribution means a Subsidiary of Borrower.

“ Tangible Net Worth ” is, on any date, the consolidated total assets of Borrower and its Subsidiaries minus (a) any amounts attributable to (i) goodwill, (ii) intangible items such as unamortized debt discount and expense, patents, trade and service marks and names, copyrights and research and development expenses except prepaid expenses, (iii) notes, accounts receivable and other obligations owing to Borrower from its officers or other Affiliates, and (iv) reserves not already deducted from assets, and (b) Total Liabilities.

“ Total Liabilities ” is on any day, obligations that should, under GAAP, be classified as liabilities on Borrower’s consolidated balance sheet, including all Indebtedness, and current portion of Subordinated Debt permitted by Bank to be paid by Borrower, but excluding all other Subordinated Debt.

“ Transfer ” is defined in Section 7.1.

[ Signature page follows. ]

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IN WITNESS WHEREOF , the parties hereto have caused this Agreement to be executed as of the Effective Date.


BORROWER:

ARCA DISCOVERY, INC.

By		/s/ Patrick Wheeler
Name:		Patrick Wheeler
Title:		SVP Finance

BANK:

SILICON VALLEY BANK

By		/s/ Adam Glick
Name:		Adam Glick
Title:		Relationship Manager


Effective Date:		July 17, 2007

[Signature page to Loan and Security Agreement]

EXHIBIT A

The Collateral consists of all of Borrower’s right, title and interest in and to the following personal property:

All goods, Accounts (including health-care receivables), Equipment, Inventory, contract rights or rights to payment of money, leases, franchise agreements, General Intangibles (except as provided below), commercial tort claims, documents, instruments (including any promissory notes), chattel paper (whether tangible or electronic), cash, deposit accounts, fixtures, letters of credit rights (whether or not the letter of credit is evidenced by a writing), securities, and all other investment property, supporting obligations, and financial assets, whether now owned or hereafter acquired, wherever located; and

all Borrower’s Books relating to the foregoing, and any and all claims, rights and interests in any of the above and all substitutions for, additions, attachments, accessories, accessions and improvements to and replacements, products, proceeds and insurance proceeds of any or all of the foregoing.

Notwithstanding the foregoing, the Collateral does not include any of the following, whether now owned or hereafter acquired: any copyright rights, copyright applications, copyright registrations and like protections in each work of authorship and derivative work, whether published or unpublished, any patents, patent applications and like protections, including improvements, divisions, continuations, renewals, reissues, extensions, and continuations-in-part of the same, trademarks, service marks and any applications therefor, whether registered or not, and the goodwill of the business of Borrower connected with and symbolized thereby, know-how, operating manuals, trade secret rights, rights to unpatented inventions, any and all intellectual property rights in computer software and computer software products, any and all design rights, all licenses or other rights to use any copyrights, patents or trademarks, all amendments, extensions, renewals and extensions of any copyrights, patents or trademarks, and any claims for damage by way of any past, present, or future infringement of any of the foregoing (collectively, “Intellectual Property”); provided, however, the Collateral shall include all Accounts, license and royalty fees and other revenues, proceeds, or income arising out of or relating to any of the foregoing.

Pursuant to the terms of a certain negative pledge arrangement with Bank, Borrower has agreed not to encumber any of its Intellectual Property, without Bank’s prior written consent.

EXHIBIT B

Loan Payment/Advance Request Form

[Omitted]

EXHIBIT C

CORPORATE BORROWING CERTIFICATE

[Omitted]

EXHIBIT D

FORM OF WARRANT

[Omitted]

Exhibit 10.11

FIRST AMENDMENT AND CONSENT

LOAN AND SECURITY AGREEMENT

THIS FIRST AMENDMENT AND CONSENT to Loan and Security Agreement (this “Amendment”) is entered into this 21st day of January, 2009, by and between Silicon Valley Bank (“Bank”) and ARCA biopharma, Inc. (f/k/a ARCA Discovery, Inc.), a Delaware corporation (“Borrower”) whose address is 8001 Arista Place, Suite 200, Broomfield, CO 80021.

RECITALS

A. Bank and Borrower have entered into that certain Loan and Security Agreement dated as of July 17, 2007 (as the same may from time to time be amended, modified, supplemented or restated, the “Loan Agreement”).

B. Bank has extended credit to Borrower for the purposes permitted in the Loan Agreement.

C. Borrower has requested that Bank amend the Loan Agreement to (i) revise the maturity date of the outstanding GC Line B Advances and (ii) make certain other revisions to the Loan Agreement as more fully set forth herein.

D. Borrower has also requested that Bank consent to the merger of a wholly-owned subsidiary of Nuvelo, Inc., a Delaware corporation (“Nuvelo”), with and into Borrower, with Borrower being the surviving corporation, pursuant to that certain Agreement and Plan of Reorganization, dated September 24, 2008, as amended by that certain Amendment No. 1 to Agreement and Plan of Reorganization, dated October 28, 2008 (as may be further amended, modified, supplemented or restate from time to time, the “Merger Agreement”, with the transactions contemplated under such Merger Agreement being hereinafter referred to as, the “Merger Transactions”). Borrower has also requested that the Bank consent to the change of Borrower’s name to ARCA biopharma Colorado, Inc. (the “Name Change”).

E. Bank has agreed to so amend certain provisions of the Loan Agreement and consent to the Merger Transactions, but only to the extent, in accordance with the terms, subject to the conditions and in reliance upon the representations and warranties set forth below.

A GREEMENT

N OW , T HEREFORE , in consideration of the foregoing recitals and other good and valuable consideration, the receipt and adequacy of which is hereby acknowledged, and intending to be legally bound, the parties hereto agree as follows:

1. Definitions. Capitalized terms used but not defined in this Amendment shall have the meanings given to them in the Loan Agreement.

2. Amendments to Loan Agreement.

2.1 Section 6.2 of the Loan Agreement is hereby deleted in its entirety and replaced with the following:

“ 6.2 Financial Statements, Reports, Certificates . Deliver to Bank: (i) within five (5) days of delivery, copies of all statements, reports and notices made

generally available to the security holders or to any holders of Subordinated Debt of Borrower’s parent company, Nuvelo, Inc.(“Parent”) , (ii) within five (5) days of filing, all reports on Form 10-K, 10-Q and 8-K filed with the Securities and Exchange Commission for Borrower’s parent company, Nuvelo, Inc. (the “Parent”) or a link thereto on Parent’s or another website on the Internet; (iii) a prompt report of any legal actions pending or threatened against Borrower or any of its Subsidiaries that could result in damages or costs to Borrower or any of its Subsidiaries of One Hundred Thousand Dollars ($100,000) or more; and (iv) budgets, sales projections, operating plans and other financial information reasonably requested by Bank.”

2.2 The definition of “GC Line B Tranche Two maturity Date” in Section 13.1 of the Loan Agreement is hereby deleted in its entirety and replaced with the following:

“ GC Line B Tranche Two Maturity Date ” is March 23, 2009.

2.3 Borrower agrees that the Initial Warrant and Additional Warrants (collectively, the “Warrants”) issued to Bank pursuant to Section 6.8 of the Loan Agreement will be assumed by Nuvelo. Such Warrants shall be exercisable for the same securities, cash, and property as would be payable for the shares issuable upon exercise of the Warrants as if such shares were outstanding on the record date for the Merger Transactions and subsequent closing. The Warrant Price (as defined in the Warrants) shall be adjusted accordingly.

3. Consent. Subject to the conditions set forth in this Amendment, Bank hereby consents to the Merger Transactions and Name Change and agrees that the Merger Transactions and the Name Change, in and of themselves, shall not constitute an Event of Default pursuant to Sections 7.2 or 7.3 of the Loan Agreement. Borrower will deliver immediate notice to Bank if the Merger Transactions are not consummated on or before January 26, 2009.

4. Limitation of Amendments.

4.1 The amendments set forth in Section 2, above, are effective for the purposes set forth herein and shall be limited precisely as written and shall not be deemed to (a) be a consent to any amendment, waiver or modification of any other term or condition of any Loan Document, or (b) otherwise prejudice any right or remedy which Bank may now have or may have in the future under or in connection with any Loan Document.

4.2 This Amendment shall be construed in connection with and as part of the Loan Documents and all terms, conditions, representations, warranties, covenants and agreements set forth in the Loan Documents, except as herein amended, are hereby ratified and confirmed and shall remain in full force and effect.

5. Representations and Warranties. To induce Bank to enter into this Amendment, Borrower hereby represents and warrants to Bank as follows:

5.1 Immediately after giving effect to this Amendment (a) the representations and warranties contained in the Loan Documents are true, accurate and complete in all material respects as of the date hereof (except to the extent such representations and warranties relate to an earlier date, in which case they are true and correct as of such date), and (b) no Event of Default has occurred and is continuing;

5.2 Borrower has the power and authority to execute and deliver this Amendment and to perform its obligations under the Loan Agreement, as amended by this Amendment;

5.3 The organizational documents of Borrower previously delivered to Bank remain true, accurate and complete and have not been amended, supplemented or restated and are and continue to be in full force and effect;

5.4 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, have been duly authorized;

5.5 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, do not and will not contravene (a) any law or regulation binding on or affecting Borrower, (b) any contractual restriction with a Person binding on Borrower, (c) any order, judgment or decree of any court or other governmental or public body or authority, or subdivision thereof, binding on Borrower, or (d) the organizational documents of Borrower;

5.6 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, do not require any order, consent, approval, license, authorization or validation of, or filing, recording or registration with, or exemption by any governmental or public body or authority, or subdivision thereof, binding on either Borrower, except as already has been obtained or made; and

5.7 This Amendment has been duly executed and delivered by Borrower and is the binding obligation of Borrower, enforceable against Borrower in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, reorganization, liquidation, moratorium or other similar laws of general application and equitable principles relating to or affecting creditors’ rights.

6. Counterparts. This Amendment may be executed in any number of counterparts and all of such counterparts taken together shall be deemed to constitute one and the same instrument.

7. Effectiveness. This Amendment shall be deemed effective upon (a) the due execution and delivery to Bank of this Amendment by each party hereto, (b) Borrower’s delivery to Bank of the filed Certificate of Merger with the Delaware Secretary of State, including any, and (c) Borrower’s payment of an amendment fee in an amount equal to $7,500 and all Bank Expenses in connection herewith.

[Signature page follows.]

I N W ITNESS W HEREOF , the parties hereto have caused this Amendment to be duly executed and delivered as of the date first written above.


BANK:		BORROWER:

SILICON VALLEY BANK		ARCA BIOPHARMA, INC.

By:	/s/ Bret J. Turner	By:	Patrick Wheeler


Print Name:		Bret J. Turner				Print Name:		Patrick Wheeler


Title:		Relationship Manager				Title:		SVP Finance

Exhibit 10.12

SECOND AMENDMENT

LOAN AND SECURITY AGREEMENT

THIS SECOND AMENDMENT to Loan and Security Agreement (this “Amendment”) is entered into this 23 ^rd day of March, 2009, by and between Silicon Valley Bank (“Bank”) and ARCA biopharma Colorado, Inc. (f/k/a ARCA biopharma, Inc.), a Delaware corporation (“Borrower”) whose address is 8001 Arista Place, Suite 200, Broomfield, CO 80021.

RECITALS

A. Bank and Borrower have entered into that certain Loan and Security Agreement dated as of July 17, 2007, as amended by a First Amendment, dated January 23, 2009 (as the same may from time to time be further amended, modified, supplemented or restated, the “Loan Agreement”).

B. Bank has extended credit to Borrower for the purposes permitted in the Loan Agreement.

C. Borrower has requested that Bank amend the Loan Agreement to revise the maturity date of the outstanding GC Line B Advances.

D. Bank has agreed to so amend certain provisions of the Loan Agreement, but only to the extent, in accordance with the terms, subject to the conditions and in reliance upon the representations and warranties set forth below.

A GREEMENT

1. Definitions. Capitalized terms used but not defined in this Amendment shall have the meanings given to them in the Loan Agreement.

2. Amendment to Loan Agreement. The definition of “GC Line B Tranche Two maturity Date” in Section 13.1 of the Loan Agreement is hereby deleted in its entirety and replaced with the following:

“ GC Line B Tranche Two Maturity Date ” is April 6, 2009.

3. Limitation of Amendment.

3.1 The amendment set forth in Section 2, above, is effective for the purposes set forth herein and shall be limited precisely as written and shall not be deemed to (a) be a consent to any amendment, waiver or modification of any other term or condition of any Loan Document, or (b) otherwise prejudice any right or remedy which Bank may now have or may have in the future under or in connection with any Loan Document.

3.2 This Amendment shall be construed in connection with and as part of the Loan Documents and all terms, conditions, representations, warranties, covenants and agreements set forth in the Loan Documents, except as herein amended, are hereby ratified and confirmed and shall remain in full force and effect.

4. Representations and Warranties. To induce Bank to enter into this Amendment, Borrower hereby represents and warrants to Bank as follows:

4.1 Immediately after giving effect to this Amendment (a) the representations and warranties contained in the Loan Documents are true, accurate and complete in all material respects as of the date hereof (except to the extent such representations and warranties relate to an earlier date, in which case they are true and correct as of such date), and (b) no Event of Default has occurred and is continuing;

4.2 Borrower has the power and authority to execute and deliver this Amendment and to perform its obligations under the Loan Agreement, as amended by this Amendment;

4.3 The organizational documents of Borrower previously delivered to Bank remain true, accurate and complete and have not been amended, supplemented or restated and are and continue to be in full force and effect;

4.4 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, have been duly authorized;

4.5 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, do not and will not contravene (a) any law or regulation binding on or affecting Borrower, (b) any contractual restriction with a Person binding on Borrower, (c) any order, judgment or decree of any court or other governmental or public body or authority, or subdivision thereof, binding on Borrower, or (d) the organizational documents of Borrower;

4.6 The execution and delivery by Borrower of this Amendment and the performance by Borrower of its obligations under the Loan Agreement, as amended by this Amendment, do not require any order, consent, approval, license, authorization or validation of, or filing, recording or registration with, or exemption by any governmental or public body or authority, or subdivision thereof, binding on either Borrower, except as already has been obtained or made; and

4.7 This Amendment has been duly executed and delivered by Borrower and is the binding obligation of Borrower, enforceable against Borrower in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, reorganization, liquidation, moratorium or other similar laws of general application and equitable principles relating to or affecting creditors’ rights.

5. Counterparts. This Amendment may be executed in any number of counterparts and all of such counterparts taken together shall be deemed to constitute one and the same instrument.

6. Effectiveness. This Amendment shall be deemed effective upon (a) the due execution and delivery to Bank of this Amendment by each party hereto and (b) Borrower’s payment of all Bank Expenses in connection herewith.

[Signature page follows.]

I N W ITNESS W HEREOF , the parties hereto have caused this Amendment to be duly executed and delivered as of the date first written above.


BANK:		BORROWER:

SILICON VALLEY BANK		ARCA BIOPHARMA COLORADO, INC.

By:	/s/ Bret J. Turner	By:	/s/ Patrick Wheeler


Print Name:		Bret J. Turner				Print Name:		Patrick Wheeler


Title:		Relationship Manager				Title:		SVP Finance

Exhibit 10.13

ARCA BIOPHARMA , I NC .

N OTE AND W ARRANT P URCHASE A GREEMENT

S EPTEMBER 24, 2008

E XECUTION V ERSION

ARCA BIOPHARMA , I NC .

N OTE AND W ARRANT P URCHASE A GREEMENT

T HIS N OTE AND W ARRANT P URCHASE A GREEMENT (this “ Agreement ”) is made as of September 24, 2008 (the “ Effective Date ”) by and between ARCA biopharma, Inc., a Delaware corporation (the “ Company ”), and the persons and entities named on the Schedule of Purchasers attached hereto (individually, a “ Purchaser ” and collectively, the “ Purchasers ”).

RECITALS

A. The Company has entered into that certain Agreement and Plan of Merger and Reorganization dated September 24, 2008, (the “ Merger Agreement ”) with Nuvelo, Inc., a Delaware corporation (“ Parent ”), and Nuvelo Acquisition Sub, Inc., a Delaware corporation and a wholly-owned subsidiary of Parent (the “ Merger Sub ”), pursuant to which Merger Sub will merge with and into the Company and the stockholders of the Company will receive shares of the capital stock of Parent in exchange for their capital stock of the Company (the “ Merger ”).

B. The Company has authorized the sale of up to $8,750,000 in principal amount of its 6% convertible promissory notes due March 31, 2009 and warrants to purchase shares of the Company’s capital stock.

C. Each Purchaser wishes to purchase a Note (as defined below) in the principal amount set forth opposite such Purchaser’s name on the Schedule of Purchasers attached hereto and a Warrant (as defined below) to purchase a number of shares of the Company’s capital stock as determined pursuant to the Warrant, on the terms and subject to the conditions set forth herein.

D. The parties desire to make Parent a third party beneficiary of certain rights and obligations under this Agreement.

AGREEMENT

NOW, THEREFORE, in consideration of the above recitals and the mutual covenants contained herein, the parties hereby agree as follows:

1.	A MOUNT AND T ERMS OF THE L OAN ; P URCHASE AND S ALE OF THE W ARRANTS .

1.1 The Loans. Subject to the terms of this Agreement, each Purchaser agrees to lend to the Company up to the total amount (the “ Loan Amount ”) set forth opposite such Purchaser’s name on the Schedule of Purchasers attached hereto under the heading “ Loan Amount ” against the issuance and delivery by the Company of a convertible promissory note for such Loan Amount in substantially the form attached hereto as Exhibit A (each, a “ Note ” and collectively, the “ Notes ”). Each Note issued pursuant to this Section 1.1 shall be convertible into capital stock of the Company as provided in such Note.

1.2 Issuance of Warrants. Subject to the terms of this Agreement, and in consideration for the purchase by the Purchasers of the Notes and for other good and valuable consideration, the Company shall issue to each Purchaser a warrant to purchase shares of Common Stock of the Company. Subject to certain adjustments provided in the warrant, each warrant issuable pursuant to this Section 1.2 shall entitle the Purchaser to acquire the number of shares equal to the quotient of (a) one-fifth ( ¹ / 5 ^th ) of such Purchaser’s Loan Amount divided by (b) the exercise price of each warrant, rounded up to the nearest share. The warrants shall be in substantially the form attached hereto as Exhibit B (each, a “ Warrant ” and collectively, the “ Warrants ”).

1.3 The Closing . The closing of the purchase and sale of the Notes and the Warrants (the “ Closing ”) shall be held on or before October 14, 2008, or at such earlier time as the Company and the Purchasers shall agree (the “ Closing Date ”), provided, however if the Merger Agreement is terminated prior to the Closing Date, then the Company and the Purchaser shall have no further rights or obligations under this Agreement following such termination and this Agreement shall be terminated without any further action by any of the parties. At the Closing, each Purchaser shall loan the Company the Loan Amount set forth opposite such Purchaser’s name on the Schedule of Purchasers under the heading “ Loan Amount .”

1.4 Delivery. At the Closing: (a) each Purchaser will deliver to the Company a check or wire transfer funds in the amount of such Purchaser’s Loan Amount, (b) the Company shall issue and deliver to each Purchaser a Note in favor of such Purchaser payable in the principal amount of such Purchaser’s Loan Amount and a Warrant as described in Section 1.2 hereof, and (c) the Company shall execute and deliver such other documents as the Purchasers shall reasonably require in order to consummate the transactions contemplated herein. In connection with the Closing, the Company shall have filed with the Delaware Secretary of State the Certificate of Amendment to the Restated Charter (as defined below) in substantially the form attached hereto as Exhibit C (the “ Charter Amendment ”).

2.	R EPRESENTATIONS AND W ARRANTIES OF THE C OMPANY .

Except as set forth on a Schedule of Exceptions delivered by the Company to Purchasers on the Effective Date, the Company represents and warrants to each Purchaser as of the Effective Date as set forth below.

2.1 Organization, Good Standing and Qualification. The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to own and operate its properties and assets, to execute and deliver this Agreement, the Notes and the Warrants (including the reservation of the shares of capital stock issuable upon conversion of the Notes and the exercise of the Warrants), to carry out the provisions of this Agreement, the Notes and the Warrants, and to carry on its business as presently conducted and as presently proposed to be conducted. The Company is duly qualified to do business and is in good standing as a foreign corporation in all jurisdictions in which the nature of its activities and of its properties (both owned and leased) makes such qualification necessary, except for those jurisdictions in which failure to do so would not have a material adverse effect on the Company or its business.

2.2 Subsidiaries. The Company does not own or control any equity security or other interest of any other corporation, partnership, limited liability company or other business entity. The Company is not a participant in any joint venture, partnership, limited liability company or similar arrangement. Since its inception, the Company has not consolidated or merged with, acquired all or substantially all of the assets of, or acquired the stock of or any interest in any corporation, partnership, limited liability company or other business entity.

2.3 Capitalization; Voting Rights.

(a) The authorized capital stock of the Company, immediately prior to the Effective Date, consists of (i) 26,000,000 shares of Common Stock, par value $0.001 per share, 5,713,818 shares of which are issued and outstanding, and (ii) 15,734,218 shares of Preferred Stock, par value $0.001 per share, (1) 9,222,257 shares of which are designated Series A Preferred Stock, all of which are issued and outstanding, (2) 3,720,692 shares of which are designated as Series B-1 Preferred Stock, 3,688,902 of which are issued and outstanding, and (3) 2,791,269 shares of which are designated as Series B-2 Preferred Stock (together with the Series A Preferred Stock, the “ Preferred Stock ”), 2,766,677 of which are issued and outstanding.

(b) Under the Company’s 2004 Stock Incentive Plan (as heretofore amended, the “ Plan ”), immediately prior to the Effective Date, (i) 600,000 shares of Common Stock have been issued pursuant to restricted stock purchase agreements and 1,665,296 shares of Common Stock have been issued pursuant to the exercise of outstanding options, (ii) options to purchase 3,385,351 shares of Common Stock have been granted and are currently outstanding as listed on Exhibit D , and (iii) 705,903 shares of Common Stock remain available for future issuance to officers, directors, employees and consultants of the Company.

(c) Other than the shares reserved for issuance under the Plan, and except as may be granted pursuant to this Agreement, the Notes and the Warrants, and as set forth on the Schedule of Exceptions, there are no outstanding options, warrants, rights (including conversion or preemptive rights and rights of first refusal), proxy or stockholder agreements, or agreements of any kind for the purchase or acquisition from the Company of any of its securities.

(d) All issued and outstanding shares of the Company’s Common Stock and Preferred Stock (i) have been duly authorized and validly issued to the persons listed on Exhibit D hereto and are fully paid and nonassessable, (ii) were issued in compliance with all applicable state and federal laws concerning the issuance of securities, and (iii) are subject to a right of first refusal in favor of the Company upon transfer.

(e) The shares of capital stock issuable upon conversion of the Notes and exercise of the Warrants have been duly and validly reserved for issuance. When issued in compliance with the provisions of the Notes or the Warrants and the Company’s Second Amended and Restated Certificate of Incorporation, as amended to date (the “ Restated Charter ”), the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants, as applicable, will be validly issued, fully paid and nonassessable, and will be free of any liens or

encumbrances other than (i) liens and encumbrances created by or imposed upon the Purchasers or (ii) as otherwise set forth in the Amended and Restated Investor Rights Agreement dated May 31, 2007 among the Company and certain stockholders of the Company (the “ Investor Rights Agreement ”), the Amended and Restated Right of First Refusal and Co-Sale Agreement dated May 31, 2007 among the Company and certain stockholders of the Company (the “ ROFR and Co-Sale Agreement ”), and the Amended and Restated Voting Agreement dated May 31, 2007 among the Company and certain stockholders of the Company (the “ Voting Agreement ”, and together with the Investor Rights Agreement and the ROFR and Co-Sale Agreement, the “ Company Agreements ”); provided, however, that such shares of capital stock may be subject to restrictions on transfer under state and/or federal securities laws. The sale of the Notes and the Warrants and the subsequent conversion of the Notes and exercise of the Warrants into shares of capital stock of the Company are not and will not be subject to any preemptive rights or rights of first refusal that have not been properly waived or complied with.

(f) Except as otherwise noted on the Schedule of Exceptions, all options granted as of the Effective Date vest as follows: 25% of the shares vest one year following the vesting commencement date, with the remaining 75% vesting in equal quarterly installments over the next three years. Except as set forth on the Schedule of Exceptions, no stock plan, stock purchase, stock option or other agreement or understanding between the Company and any holder of any equity securities or rights to purchase equity securities provides for acceleration or other changes in the vesting provisions or other terms of such agreement or understanding as the result of (i) termination of employment or consulting services (whether actual or constructive); (ii) any merger, consolidated sale of stock or assets, change in control or any other transaction(s) by the Company; or (iii) the occurrence of any other event or combination of events.

(g) All outstanding shares of Common Stock and Preferred Stock, and all shares of Common Stock and Preferred Stock issuable upon the exercise or conversion of outstanding options, warrants or other exercisable or convertible securities are subject to a market standoff or “lockup” agreement of not less than 180 days following the Company’s initial public offering.

2.4 Authorization; Binding Obligations. All corporate action on the part of the Company, its officers, directors and stockholders necessary for the authorization of this Agreement and the Notes, the performance of all obligations of the Company hereunder and thereunder at the Closing and the authorization, sale, issuance and delivery of the Notes and the Warrants pursuant hereto (and the reservation of the shares of capital stock issuable upon conversion of the Notes and exercise of the Warrants) pursuant to the Restated Charter has been taken. The Agreement, the Notes and the Warrants, when executed and delivered, will be valid and binding obligations of the Company enforceable in accordance with their terms, except (a) as limited by applicable bankruptcy, insolvency, reorganization, moratorium or other laws of general application affecting enforcement of creditors’ rights, and (b) general principles of equity that restrict the availability of equitable remedies.

2.5 Financial Statements. The Company has made available to each Purchaser its audited balance sheet as of December 31, 2007, an audited statement of income and cash flows for the twelve months ending December 31, 2007, an unaudited balance sheet as of June 30, 2008

and an unaudited statement of income and cash flows for the year to date ending June 30, 2008 (collectively, the “ Financial Statements ”). The Financial Statements present fairly the financial condition and position of the Company as of their respective dates.

2.6 Liabilities. The Company has no material liabilities and, to the best of its knowledge no material contingent liabilities, not disclosed in the Financial Statements, except current liabilities incurred in the ordinary course of business which have not been, either in any individual case or in the aggregate, materially adverse.

2.7 Agreements; Action.

(a) Except for agreements explicitly contemplated hereby and agreements between the Company and its employees with respect to the sale of the Company’s outstanding Common Stock, there are no agreements, understandings or proposed transactions between the Company and any of its officers, directors, employees, affiliates or any affiliate thereof.

(b) There are no agreements, understandings, instruments, contracts, proposed transactions, judgments, orders, writs or decrees to which the Company is a party or to its knowledge by which it is bound which may involve (i) future obligations (contingent or otherwise) of, or payments to, the Company in excess of $50,000, or (ii) the transfer or license of any patent, copyright, trade secret or other proprietary right to or from the Company (other than licenses by the Company of “off the shelf” or other standard products), or (iii) provisions restricting the development, manufacture or distribution of the Company’s products or services, or (iv) indemnification by the Company with respect to infringements of proprietary rights.

(c) The Company has not (i) accrued, declared or paid any dividends, or authorized or made any distribution upon or with respect to any class or series of its capital stock, (ii) incurred or guaranteed any indebtedness for money borrowed or any other liabilities (other than trade payables incurred in the ordinary course of business or as disclosed in the Financial Statements) individually in excess of $10,000 or, in the case of indebtedness and/or liabilities individually less than $10,000, in excess of $25,000 in the aggregate, (iii) made any loans or advances to any person, other than ordinary advances for travel expenses, or (iv) sold, exchanged or otherwise disposed of any of its assets or rights, other than the sale of its inventory in the ordinary course of business.

(d) For the purposes of subsections (b) and (c) above, all indebtedness, liabilities, agreements, understandings, instruments, contracts and proposed transactions involving the same person or entity (including persons or entities the Company has reason to believe are affiliated therewith) shall be aggregated for the purpose of meeting the individual minimum dollar amounts of such subsections.

(e) The Company has not engaged in the past three months in any discussion (i) with any representative of any other business or businesses regarding the consolidation or merger of the Company with or into any such other business or businesses, (ii) with any corporation, partnership, limited liability company, or other business entity or any individual regarding the sale, conveyance or disposition of all or substantially all of the assets of the

Company, or a transaction or series of related transactions in which more than 50% of the voting power of the Company is disposed of, or (iii) regarding any other form of acquisition, liquidation, dissolution or winding up, of the Company.

2.8 Obligations to Related Parties . There are no obligations of the Company to officers, directors, stockholders, or employees of the Company other than (a) for payment of salary for services rendered, (b) reimbursement for reasonable expenses incurred on behalf of the Company and (c) for other standard employee benefits made generally available to all employees (including stock option agreements outstanding under any stock option plan approved by the Board of Directors of the Company). None of the officers, directors or, to the best of the Company’s knowledge, key employees or stockholders of the Company, or any members of their immediate families, is indebted to the Company or has any direct or indirect ownership interest in any firm or corporation with which the Company is affiliated or with which the Company has a business relationship, or any firm or corporation that competes with the Company, other than (i) passive investments in publicly traded companies (representing less than 1% of such company) which may compete with the Company and (ii) investments by venture capital funds with which directors of the Company may be affiliated and service as a board member of a company in connection therewith due to a person’s affiliation with a venture capital fund or similar institutional investor in such company. No officer, director or stockholder, or any member of their immediate families, is, directly or indirectly, interested in any material contract with the Company (other than such contracts as relate to any such person’s ownership of capital stock or other securities of the Company).

2.9 Changes. Since June 30, 2008, there has not been to the Company’s knowledge:

(a) Any change in the assets, liabilities, financial condition, prospects or operations of the Company from that reflected in the Financial Statements, other than changes in the ordinary course of business, none of which individually or in the aggregate has had or would reasonably be expected to have a material adverse effect on such assets, liabilities, financial condition, prospects or operations of the Company;

(b) Any resignation or termination of any officer, key employee or group of employees of the Company;

(c) Any material change, except in the ordinary course of business, in the contingent obligations of the Company by way of guaranty, endorsement, indemnity, warranty or otherwise;

(d) Any damage, destruction or loss, whether or not covered by insurance, materially and adversely affecting the properties, business or prospects or financial condition of the Company;

(e) Any waiver by the Company of a valuable right or of a material debt owed to it;

(f) Any material change in any compensation arrangement or agreement with any employee, officer, director or stockholder;

(g) Any labor organization activity related to the Company;

(h) Any sale, assignment, or exclusive license or transfer of any patents, trademarks, copyrights, trade secrets or other intangible assets;

(i) Any change in any material agreement to which the Company is a party or by which it is bound which materially and adversely affects the business, assets, liabilities, financial condition, operations or prospects of the Company;

(j) Any other event or condition of any character that, either individually or cumulatively, has materially and adversely affected the business, assets, liabilities, financial condition, prospects or operations of the Company; or

(k) Any arrangement or commitment by the Company to do any of the acts described in subsection (a) through (j) above.

2.10 Title to Properties and Assets; Liens, Etc. The Company has good and marketable title to its properties and assets, including the properties and assets reflected in the most recent balance sheet included in the Financial Statements, and good title to its leasehold estates, in each case subject to no mortgage, pledge, lien, lease, encumbrance or charge, other than (a) those resulting from taxes which have not yet become delinquent, (b) minor liens and encumbrances which do not materially detract from the value of the property subject thereto or materially impair the operations of the Company, and (c) those that have otherwise arisen in the ordinary course of business. All facilities, machinery, equipment, fixtures, vehicles and other properties owned, leased or used by the Company are in good operating condition and repair and are reasonably fit and usable for the purposes for which they are being used.

2.11 Intellectual Property.

(a) The Company owns or possesses sufficient legal rights to all trademarks, service marks, trade names, copyrights, licenses, information and other proprietary rights and processes necessary for its business as now conducted and as presently proposed to be conducted, without any infringement of the rights of others. To the Company’s knowledge, the Company owns or possesses sufficient legal rights to all patents and trade secrets necessary for its business as now conducted and as presently proposed to be conducted, without any infringement of the rights of others. There are no outstanding options, licenses or agreements of any kind relating to the foregoing proprietary rights, nor is the Company bound by or a party to any options, licenses or agreements of any kind with respect to the patents, trademarks, service marks, trade names, copyrights, trade secrets, licenses, information and other proprietary rights and processes of any other person or entity other than such licenses or agreements arising from the purchase of “off the shelf” or standard products. To the Company’s knowledge, no claims are currently being asserted against the Company, nor are there any claims threatened in writing, by any third party challenging or questioning the Company’s right to use any of the patents, trademarks, service marks, trade names, copyrights, trade secrets, information or other proprietary rights and processes owned or used by the Company or the validity or effectiveness of any license or similar agreement with respect thereto.

(b) No product or service marketed or sold (or proposed to be marketed or sold) by the Company violates or will violate any license or infringe any trademarks, service marks, trade names, copyrights or other proprietary rights of any other person or entity. The Company has not received any communications alleging that the Company has violated or, by conducting its business as presently proposed to be conducted, would violate any of the trademarks, service marks, trade names, copyrights or other proprietary rights of any other person or entity. To the Company’s knowledge, no product or service marketed or sold (or proposed to be marketed or sold) by the Company violates or will violate any patents or trade secrets of any other person or entity. The Company has not received any communications alleging that the Company has violated or, by conducting its business as presently proposed to be conducted, would violate any of the patents or trade secrets of any other person or entity.

(c) The Company is not aware that any of its employees is obligated under any contract (including licenses, covenants or commitments of any nature) or other agreement, or subject to any judgment, decree or order of any court or administrative agency, that would interfere with their duties to the Company or that would conflict with the Company’s business as proposed to be conducted. Each former and current employee, officer and consultant of the Company has executed a proprietary information and inventions agreement in the forms delivered to the Purchasers’ counsel. No former and current employee, officer or consultant of the Company has excluded works or inventions made prior to his or her employment with the Company from his or her assignment of inventions pursuant to such employee, officer or consultant’s proprietary information and inventions agreement. The Company does not believe it is or will be necessary to utilize any inventions, trade secrets or proprietary information of any of its employees made prior to their employment by the Company, except for inventions, trade secrets or proprietary information that have been assigned to the Company.

2.12 Compliance with Other Instruments. The Company is not in violation or default of any term of its Restated Charter or its bylaws, each as amended. The Company is not in violation of any provision of any mortgage, indenture, contract, lease, agreement, instrument or contract to which it is party or by which it is bound or of any judgment, decree, order or writ, other than any such violation that would not have a material adverse effect on the Company. The execution, delivery, and performance of and compliance with this Agreement, the Notes and the Warrants, and the issuance and sale of the Notes, the Warrants and the shares of capital stock issuable upon conversion of the Notes and the exercise of the Warrants pursuant hereto and the Restated Charter, will not, with or without the passage of time or giving of notice, result in any such violations, or be in conflict with or constitute a default under any such term or provision, or result in the creation of any mortgage, pledge, lien, encumbrance or charge upon any of the properties or assets of the Company or the suspension, revocation, impairment, forfeiture or nonrenewal of any permit, license, authorization or approval applicable to the Company, its business or operations or any of its assets or properties. To the Company’s knowledge, the Company has avoided every condition, and has not performed any act, the occurrence of which would result in the Company’s loss of any right granted under any license, distribution agreement or other agreement required to be disclosed on the Schedule of Exceptions.

2.13 Litigation. There is no action, suit, proceeding or investigation pending or, to the Company’s knowledge, currently threatened against the Company that would reasonably be

expected to result, either individually or in the aggregate, in any material adverse change in the assets, condition, affairs or prospects of the Company, financially or otherwise, or any change in the current equity ownership of the Company or that questions the validity of this Agreement, the Notes or the Warrants or the right of the Company to enter into this Agreement, the Notes or the Warrants, or to consummate the transactions contemplated hereby or thereby, nor is the Company aware that there is any basis for any of the foregoing. The foregoing includes, without limitation, actions pending or, to the Company’s knowledge, threatened or any basis therefor known by the Company involving the prior employment of any of the Company’s employees, their use in connection with the Company’s business of any information or techniques allegedly proprietary to any of their former employers, or their obligations under any agreements with prior employers. The Company is not a party to, or to the Company’s knowledge subject to, the provisions of any order, writ, injunction, judgment or decree of any court or government agency or instrumentality. There is no action, suit, proceeding or investigation by the Company currently pending or which the Company intends to initiate.

2.14 Tax Returns and Payments. The Company is and always has been a subchapter C corporation. The Company has timely filed all tax returns (federal, state and local) required to be filed by it. All taxes shown to be due and payable on such returns, any assessments imposed, and to the Company’s knowledge all other taxes due and payable by the Company on or before the Effective Date, have been paid or will be paid prior to the time they become delinquent. The Company has not been advised (a) that any of its returns, federal, state or other, have been or are being audited as of the date hereof, or (b) of any deficiency in assessment or proposed judgment to its federal, state or other taxes. The Company has no knowledge of any liability of any tax to be imposed upon its properties or assets as of the date of this Agreement that is not adequately provided for.

2.15 Employees. The Company has no collective bargaining agreements with any of its employees. There is no labor union organizing activity pending or, to the Company’s knowledge, threatened with respect to the Company. The Company is not a party to or bound by any currently effective employment contract, deferred compensation arrangement, bonus plan, incentive plan, profit sharing plan, retirement agreement or other employee compensation plan or agreement. No employee of the Company has been granted the right to continued employment by the Company or to any material compensation following termination of employment with the Company. To the Company’s knowledge, no employee of the Company, nor any consultant with whom the Company has contracted, is in violation of any term of any employment contract, proprietary information agreement or any other agreement relating to the right of any such individual to be employed by, or to contract with, the Company; and to the Company’s knowledge the continued employment by the Company of its present employees, and the performance of the Company’s contracts with its independent contractors, will not result in any such violation. The Company has not received any notice alleging that any such violation has occurred. The Company is not aware that any officer, key employee or group of employees intends to terminate his, her or their employment with the Company, nor does the Company have a present intention to terminate the employment of any officer, key employee or group of employees. Each former employee of the Company whose employment was terminated by the Company has entered into an agreement with the Company providing for the full release of any claims against the Company or any related party arising out of such employment. There are no actions pending, or to the Company’s knowledge, threatened, by any former or current employee concerning such person’s employment by the Company.

2.16 Obligations of Management. Each officer and key employee of the Company is currently devoting substantially all of his or her business time to the conduct of the business of the Company. The Company is not aware that any officer or key employee of the Company is planning to work less than full time at the Company in the future. No officer or key employee is currently working or, to the Company’s knowledge, plans to work for a competitive enterprise, whether or not such officer or key employee is or will be compensated by such enterprise.

2.17 Registration Rights and Voting Rights. Except as required pursuant to the Investor Rights Agreement, the Company is presently not under any obligation, and has not granted any rights, to register under the Securities Act of 1933, as amended (the “ Securities Act ”), any of the Company’s presently outstanding securities or any of its securities that may hereafter be issued. To the Company’s knowledge, except the Voting Agreement, no stockholder of the Company has entered into any agreement with respect to the voting of equity securities of the Company.

2.18 Compliance with Laws; Permits. To its knowledge, the Company is not in violation of any applicable statute, rule, regulation, order or restriction of any domestic or foreign government or any instrumentality or agency thereof in respect of the conduct of its business or the ownership of its properties, which violation would materially and adversely affect the business, assets, liabilities, financial condition, operations or prospects of the Company. No governmental orders, permissions, consents, approvals or authorizations are required to be obtained and no registrations or declarations are required to be filed in connection with the execution and delivery of this Agreement or the issuance of the Notes or the shares of capital stock issuable upon conversion of the Notes, except such as have been duly and validly obtained or filed, or with respect to any filings that must be made after the Effective Date, as will be filed in a timely manner. The Company has all franchises, permits, licenses and any similar authority necessary for the conduct of its business as now being conducted by it, the lack of which could materially and adversely affect the business, assets, properties, prospects or financial condition of the Company and believes it can obtain, without undue burden or expense, any similar authority for the conduct of its business as planned to be conducted.

2.19 Environmental and Safety Laws. To its knowledge, the Company is not in violation of any applicable statute, law or regulation relating to the environment or occupational health and safety, and to its knowledge, no material expenditures are or will be required in order to comply with any such existing statute, law or regulation. No Hazardous Materials (as defined below) are used or have been used, stored, or disposed of by the Company or, to the Company’s knowledge, by any other person or entity on any property owned, leased or used by the Company. For the purposes of the preceding sentence, “Hazardous Materials” shall mean (a) materials which are listed or otherwise defined as “hazardous” or “toxic” under any applicable local, state, federal and/or foreign laws and regulations that govern the existence and/or remedy of contamination on property, the protection of the environment from contamination, the control of hazardous wastes, or other activities involving hazardous substances, including building materials, or (b) any petroleum products or nuclear materials.

2.20 Offering Valid. Assuming the accuracy of the representations and warranties of Purchasers contained in Section 3.2 hereof, the offer, sale and issuance of the Notes, the Warrants and the shares of the Company’s capital stock issuable upon conversion of the Notes and exercise of the Warrants will be exempt from the registration requirements of the Securities Act, and will have been registered or qualified (or are exempt from registration and qualification) under the registration, permit or qualification requirements of all applicable state securities laws. Neither the Company nor any agent on its behalf has solicited or will solicit any offers to sell or has offered to sell or will offer to sell all or any part of the Notes or Warrants to any person or persons so as to bring the sale of such Notes or Warrants by the Company within the registration provisions of the Securities Act or any state securities laws.

2.21 Full Disclosure. The Company has provided Purchasers with all information requested by the Purchasers in connection with their decision to purchase the Notes and the Warrants. To the Company’s knowledge after due inquiry, neither this Agreement, the exhibits hereto, the Notes, the Warrants nor any other document delivered by the Company to Purchasers or their attorneys or agents in connection herewith or with the transactions contemplated hereby, contain any untrue statement of a material fact nor, to the Company’s knowledge after due inquiry, omit to state a material fact necessary in order to make the statements contained herein or therein not misleading. Notwithstanding the foregoing, the documents provided to the Purchasers describing the Company’s business were prepared by the management of the Company in a good faith effort to describe the Company’s presently proposed business and products and the markets therefore. The assumptions applied in preparing these documents appeared reasonable to management as of the date thereof; however, there is no assurance that these assumptions will prove to be valid or that the objectives set forth in these documents will be achieved.

2.22 Minute Books. The minute books of the Company made available to Purchasers document all meetings of directors and stockholders since the time of incorporation.

2.23 Section 83(b) Elections. To the Company’s knowledge, all elections and notices permitted by Section 83(b) of the Internal Revenue Code of 1986, as amended, (the “ Code ”) and any analogous provisions of applicable state tax laws have been timely filed by all employees who have purchased shares of the Company’s Common Stock under agreements that provide for the vesting of such shares.

2.24 Insurance. The Company has or will obtain promptly following the Effective Date general commercial, product liability, fire and casualty insurance policies with coverage customary for companies similarly situated to the Company.

2.25 Executive Officers. To the Company’s knowledge, no executive officer or person nominated to become an executive officer of the Company (a) has been convicted in a criminal proceeding or is a named subject of a pending criminal proceeding (excluding minor traffic violations) or (b) is or has been subject to any judgment or order of, the subject of any pending civil or administrative action by the Securities and Exchange Commission or any self-regulatory organization.

2.26 Qualified Small Business. The Company is a “qualified small business” within the meaning of Section 1202(d) of the Code and of the date hereof and the shares of the Company’s capital stock issuable upon conversion of the Notes and exercise of the Warrants should qualify as “qualified small business stock” as defined in Section 1202(c) of the Code as of the date hereof. As of the date hereof, the Company meets the “active business requirement” of Section 1202(e) of the Code, and it has made no “significant redemptions” within the meaning of Section 1202(c)(3)(B) of the Code.

2.27 Sudanese Investments. The Company and each of its subsidiaries does not, directly or indirectly, own or control any property or assets located in the Republic of the Sudan or transact any commercial business in the Republic of the Sudan.

3.	R EPRESENTATIONS AND W ARRANTIES OF THE P URCHASERS .

Each Purchaser hereby represents and warrants to the Company, severally and not jointly, as follows (provided that such representations and warranties do not lessen or obviate the representations and warranties of the Company set forth in this Agreement):

3.1 Requisite Power and Authority. Purchaser has all necessary power and authority to execute and deliver this Agreement and to carry out its provisions. All action on Purchaser’s part required for the lawful execution and delivery of this Agreement has been taken. Upon its execution and delivery, this Agreement will be a valid and binding obligation of Purchaser, enforceable in accordance with its terms, except (a) as limited by applicable bankruptcy, insolvency, reorganization, moratorium or other laws of general application affecting enforcement of creditors’ rights, and (b) as limited by general principles of equity that restrict the availability of equitable remedies.

3.2 Investment Representations. Purchaser understands that none of the Notes, the Warrants or the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants have been registered under the Securities Act. Purchaser also understands that the Notes and Warrants are being offered and sold pursuant to an exemption from registration contained in the Securities Act based in part upon Purchaser’s representations contained in the Agreement. Purchaser hereby represents and warrants as follows:

(a) Purchaser Bears Economic Risk. Purchaser has substantial experience in evaluating and investing in private placement transactions of securities in companies similar to the Company so that it is capable of evaluating the merits and risks of its investment in the Company and has the capacity to protect its own interests. Purchaser must bear the economic risk of this investment indefinitely unless the Notes, the Warrants or the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants are registered pursuant to the Securities Act, or an exemption from registration is available. Purchaser understands that the Company has no present intention of registering the Notes, the Warrants, the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants or any shares of its Common Stock. Purchaser also understands that there is no assurance that any exemption from registration under the Securities Act will be available and that, even if available, such exemption may not allow Purchaser to transfer all or any portion of the Notes, the Warrants or shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants under the circumstances, in the amounts or at the times Purchaser might propose.

(b) Acquisition for Own Account. Purchaser is acquiring the Notes, the Warrants and (and, if issued, the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants) for Purchaser’s own account for investment only, and not with a view towards their distribution.

(c) Purchaser Can Protect Its Interest. Purchaser represents that by reason of its, or of its management’s, business or financial experience, Purchaser has the capacity to protect its own interests in connection with the transactions contemplated in this Agreement. Further, Purchaser is aware of no publication of any advertisement in connection with the transactions contemplated in the Agreement.

(d) Accredited Investor. Purchaser represents that it is an accredited investor within the meaning of Regulation D under the Securities Act.

(e) Company Information. Purchaser has received and read the Financial Statements and other documents provided by Company concerning its business, and has had an opportunity to discuss the Company’s business, management and financial affairs with directors, officers and management of the Company and has had the opportunity to review the Company’s operations and facilities. Purchaser has also had the opportunity to ask questions of and receive answers from, the Company and its management regarding the terms and conditions of this investment.

(f) Rule 144. Purchaser acknowledges and agrees that the Notes, the Warrants and the shares of capital stock issuable upon conversion of the Notes and exercise of the Warrants, if issued, are “restricted securities” as defined in Rule 144 promulgated under the Securities Act as in effect from time to time and must be held indefinitely unless they are subsequently registered under the Securities Act or an exemption from such registration is available. Purchaser has been advised or is aware of the provisions of Rule 144, which permits limited resale of shares purchased in a private placement subject to the satisfaction of certain conditions, including, among other things: the availability of certain current public information about the Company, the resale occurring following the required holding period under Rule 144 and the number of shares being sold during any three month period not exceeding specified limitations.

(g) Residence. If Purchaser is an individual, then Purchaser resides in the state or province identified in the address of Purchaser set forth on Exhibit A ; if Purchaser is a partnership, corporation, limited liability company or other entity, then the office or offices of Purchaser in which its investment decision was made is located at the address or addresses of Purchaser set forth on Exhibit A (except as any Purchaser shall otherwise notify the Company in writing prior to the Closing).

(h) Foreign Investors. If Purchaser is not a United States person (as defined by Section 7701(a)(30) of the Internal Revenue Code of 1986, as amended), Purchaser hereby represents that it has satisfied itself as to the full observance of the laws of its jurisdiction in

connection with any invitation to subscribe for the Notes or the Warrants or any use of this Agreement, including (i) the legal requirements within its jurisdiction for the purchase of the Notes and the Warrants, (ii) any foreign exchange restrictions applicable to such purchase, (iii) any government or other consents that may need to be obtained, and (iv) the income tax and other tax consequences, if any, that may be relevant to the purchase, holding, redemption, sale or transfer of the Notes, the Warrants and the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants. The Company’s offer and sale and Purchaser’s subscription and payment for and continued beneficial ownership of the Notes, the Warrants and if issued, the shares of capital stock issuable upon conversion of the Notes or exercise of the Warrants, will not violate any applicable securities or other laws of Purchaser’s jurisdiction.

3.3 Transfer Restrictions. Each Purchaser acknowledges and agrees that, if issued, the shares of capital stock issuable upon conversion of the Notes and exercise of the Warrants are subject to restrictions on transfer as set forth in the Company Agreements.

4.	C OVENANTS .

4.1 Waiver of Right of First Refusal. The Company is required to provide each Investor (as defined in the Investor Rights Agreement) with fifteen (15) days prior written notice before it sells its Equity Securities (as defined in the Investor Rights Agreement) in accordance with Section 4 of the Investor Rights Agreement. Each Purchaser hereby waives its right to purchase its pro rata share of the Notes and the Warrants, and, in connection with such waiver, hereby waives the fifteen (15) day notice period to exercise such right on behalf of itself and all of the other Investors. The waiver contained in this Section 4.1 shall be in connection with (a) the issuance and sale of the Notes and Warrants pursuant to this Agreement, and (b) the issuance of any shares of capital stock upon the conversion of the Notes and exercise of the Warrants, but not with respect to any future issuances of securities by the Company.

5.	M ISCELLANEOUS .

5.1 Binding Agreement. The terms and conditions of this Agreement shall inure to the benefit of and be binding upon the respective successors and assigns of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any third party any rights, remedies, obligations, or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement.

5.2 Governing Law. This Agreement shall be governed by and construed under the laws of the State of Colorado in all respects as such laws are applied to agreements among Colorado residents entered into and performed entirely within Colorado, without giving effect to conflict of law principles thereof. The parties agree that any action brought by any party under or in relation to this Agreement, including without limitation to interpret or enforce any provision of this Agreement, shall be brought in, and each party agrees to and does hereby submit to the jurisdiction and venue of, any state or federal court located in the County of Denver, Colorado.

5.3 Survival. The representations, warranties, covenants and agreements made herein shall survive the closing of the transactions contemplated hereby. All statements as to factual

matters contained in any certificate or other instrument delivered by or on behalf of the Company pursuant hereto in connection with the transactions contemplated hereby shall be deemed to be representations and warranties by the Company hereunder solely as of the date of such certificate or instrument. The representations, warranties, covenants and obligations of the Company, and the rights and remedies that may be exercised by the Purchasers, shall not be limited or otherwise affected by or as a result of any information furnished to, or any investigation made by or knowledge of, any of the Purchasers or any of their representatives.

5.4 Counterparts. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

5.5 Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.

5.6 Notices. Any notice required or permitted under this Agreement shall be given in writing and shall be deemed effectively given upon personal delivery or upon deposit with the United States Post Office or Federal Express, postage prepaid, addressed (a) to the Company at ARCA biopharma, Inc., 8001 Arista Place, Suite 200, Broomfield, CO 80021, Attention: Chief Executive Officer and General Counsel, or (b) to a Purchaser at its address shown on the Schedule of Purchasers, or at such other address as such party may designate by ten (10) days advance written notice to the other party.

5.7 Modification; Waiver. No modification or waiver of any provision of this Agreement or consent to departure therefrom shall be effective unless in writing and approved by the Company, a majority of the Principal Series Preferred Stockholders (as such term is defined in the Company’s Second Amended and Restated Certificate of Incorporation) and, for so long as the Merger Agreement remains in full force and effect, Parent.

5.8 Entire Agreement. This Agreement and the Schedules and Exhibits hereto constitute the full and entire understanding and agreement between the parties with regard to the subjects hereof and no party shall be liable or bound to any other in any manner by any representations, warranties, covenants and agreements except as specifically set forth herein.

5.9 Expenses. Each party shall pay all costs and expenses that it incurs with respect to the negotiation, execution, delivery and performance of the Agreement.

5.10 Exculpation Among Purchasers. Each Purchaser acknowledges that it is not relying upon any person, firm, or corporation, other than the Company and its officers and directors, in making its investment or decision to invest in the Company. Each Purchaser agrees that no Purchaser nor the respective controlling persons, officers, directors, partners, agents, or employees of any Purchaser shall be liable to any other Purchaser for any action heretofore taken or omitted to be taken by any of them in connection with the purchase of the Notes and the Warrants.

5.11 Third Party Beneficiary Rights. No provisions of this Agreement are intended, nor shall be interpreted, to provide or create any third party beneficiary rights or any other rights

of any kind in any client, customer, employee, affiliate, stockholder, partner or any party hereto or any other person unless specifically provided otherwise herein and, except as so provided, all provisions hereof shall be personal solely between the parties to this Agreement; except that for so long as the Merger Agreement remains in full force and effect, this Agreement is intended to benefit Parent and Parent shall have the right to enforce as a third party beneficiary the rights of the Company and obligations of the Purchasers under this Agreement.

5.12 Pronouns. All pronouns contained herein, and any variations thereof, shall be deemed to refer to the masculine, feminine or neutral, singular or plural, as to the identity of the parties hereto may require.

5.13 Remedies. The Company and the Purchasers acknowledge and agree that irreparable damage would occur in the event that any of the provisions of this Agreement were not performed in accordance with their specific terms or were otherwise breached. It is accordingly agreed that the Company shall be entitled to an injunction or injunctions to prevent or cure breaches of the provisions of this Agreement by any Purchaser and to enforce specifically the terms and provisions hereof, this being in addition to any other remedy to which the Company may be entitled by law or equity.

[Signature pages follow]

I N W ITNESS W HEREOF , the parties have executed this N OTE AND W ARRANT P URCHASE A GREEMENT as of the date first written above.


COMPANY:		PURCHASERS:

ARCA BIOPHARMA , I NC .		S KYLINE V ENTURE P ARTNERS Q UALIFIED P URCHASER F UND IV, L.P.

Signature:	/s/ Richard B. Brewer	By:	Skyline Venture Management IV, LLC
			Its General Partner
Print Name:	Richard B. Brewer

Title:	President and Chief Executive Officer
		By:	/s/ John G. Freund
			John G Freund, Managing Director

		I NTER W EST P ARTNERS IX, LP

		By:	InterWest Management Partners IX, LLC

		By:	/s/ Linda Grais
			Linda Grais, Venture Member

		A TLAS V ENTURE F UND VII, L.P.

		By:	Atlas Venture Associates VII, L.P. its General Partner

		By:	Atlas Venture Associates VII, Inc. its General Partner

		Signature:	/s/ Jeanne Henry Larkin

		Print Name:	Jeanne Henry Larkin

		Title:	Vice President

NOTE AND WARRANT PURCHASE AGREEMENT

SIGNATURE PAGE


						B OULDER V ENTURES IV, L.P.

						By: BV Partners IV, L.L.C., its General Partner

						Signature:		/s/ Kyle Lefkoff

						Print Name:		Kyle Lefkoff

						Title:		Managing Member

						B OULDER V ENTURES IV (A NNEX ), L.P.

						By: BV Partners IV, L.L.C., its General Partner

						Signature:		/s/ Kyle Lefkoff

						Print Name:		Kyle Lefkoff

						Title:		Managing Member

						T HE P EIERLS F OUNDATION , I NC .

						By:		The Peierls Foundation, Inc.

						Signature:		/s/ E. Jeffrey Peierls

						Print Name:		E. Jeffrey Peierls

						Title:		President

NOTE AND WARRANT PURCHASE AGREEMENT

SIGNATURE PAGE

SCHEDULE OF PURCHASERS


N AME AND A DDRESS	L OAN A MOUNT
S KYLINE V ENTURE P ARTNERS Q UALIFIED P URCHASER F UND IV, L.P. 525 University Ave Suite 520 Palo Alto, CA 94301 Attention: Kerry Kenny Facsimile: (650) 329-1090	$	1,825,696

I NTER W EST P ARTNERS IX, LP 2710 Sand Hill Road Second Floor Menlo Park, CA 94025 Attention: Linda Grais Facsimile: (650) 854-4706	$	1,461,872

A TLAS V ENTURE F UND VII, L.P. 890 Winter Street, Suite 320 Waltham, MA 02451 Attention: General Counsel Facsimile: (781) 622-1701	$	3,674,630

B OULDER V ENTURES IV, L.P. 1900 Ninth Street, Suite 200 Boulder, CO 80302 Attention: Kyle Lefkoff Facsimile: (303) 444-0267	$	92,393

B OULDER V ENTURES IV (A NNEX ), L.P. 1900 Ninth Street, Suite 200 Boulder, CO 80302 Attention: Kyle Lefkoff Facsimile: (303) 444-0267	$	1,395,409

T HE P EIERLS F OUNDATION , I NC . c/o U.S. Trust Company of N.Y. 114 West 47 ^th Street New York, NY 10036 Attention: Mr. John Kennedy	$	300,000

T OTAL	$	8,750,000.00

E XHIBIT A

F ORM OF C ONVERTIBLE P ROMISSORY N OTE

[Omitted]

E XHIBIT B

F ORM OF W ARRANT

[Omitted]

E XHIBIT C

C HARTER A MENDMENT

[Omitted]

E XHIBIT D

C APITALIZATION

[Omitted]

Exhibit 10.14

ARCA BIOPHARMA , I NC .

F IRST A MENDMENT TO N OTE AND W ARRANT P URCHASE A GREEMENT

T HIS F IRST A MENDMENT TO N OTE AND W ARRANT P URCHASE A GREEMENT (this “ Amendment ”) is made and entered into as of October 10, 2008 by and between ARCA biopharma, Inc., a Delaware corporation (the “ Company ”), the undersigned Purchasers (individually, a “ Purchaser ” and collectively, the “ Purchasers ”) and Parent.

RECITALS

A. The Company has authorized the sale of its 6% convertible promissory notes due March 31, 2009 and warrants to purchase shares of the Company’s capital stock.

B. The Company and the Purchasers have entered into that certain Note and Warrant Purchase Agreement, dated September 24, 2008 (the “ Purchase Agreement ”) pursuant to which the Purchasers agreed to purchase the Notes at the Closing. Capitalized terms used, but not defined herein, shall have the meanings assigned to them in the Purchase Agreement.

C. Section 5.7 of the Purchase Agreement allows the Company, a majority of the Principal Series Preferred Stockholders (as such term is defined in the Restated Charter) and, for so long as the Merger Agreement remains in full force and effect, Parent, to amend the Purchase Agreement.

D. The Company, the undersigned Purchasers, who represent at least a majority of the Principal Series Preferred Stockholders (as such term is defined in the Restated Charter), and Parent, desire to amend the Purchase Agreement as provided below.

AMENDMENT

NOW, THEREFORE, in consideration of the above recitals and the mutual covenants contained herein, the parties hereby agree as follows:

1. Section 1.2 of the Purchase Agreement is hereby deleted in its entirety and replaced with the following language:

1.2 Issuance of Warrants. Subject to the terms of this Agreement, and for the additional consideration (the “ Warrant Consideration ”) set forth opposite such Purchaser’s name on the Schedule of Purchasers under the heading “ Warrant Consideration ,” the Company shall issue to each Purchaser a warrant to purchase shares of Common Stock of the Company. Subject to certain adjustments provided in the warrant, each warrant issuable pursuant to this Section 1.2 shall entitle the Purchaser to acquire the number of shares equal to the quotient of (a) one-fifth ( ¹ / 5 ^th ) of such Purchaser’s total purchase price (“ Total Purchase Price ”) set forth opposite such

Purchaser’s name on the Schedule of Purchasers under the heading “ Total Purchase Price ”) divided by (b) the exercise price of each warrant, rounded up to the nearest share. The warrants shall be in substantially the form attached hereto as Exhibit B (each, a “ Warrant ” and collectively, the “ Warrants ”).

2. Section 1.4 of the Purchase Agreement is hereby deleted in its entirety and replaced with the following language:

1.4 Delivery. At the Closing: (a) each Purchaser will deliver to the Company a check or wire transfer funds in the total amount of such Purchaser’s Total Purchase Price, (b) the Company shall issue and deliver to each Purchaser a Note in favor of such Purchaser payable in the principal amount of such Purchaser’s Loan Amount and a Warrant, and (c) the Company shall execute and deliver such other documents as the Purchasers shall reasonably require in order to consummate the transactions contemplated herein. In connection with the Closing, the Company shall have filed with the Delaware Secretary of State the Certificate of Amendment to the Restated Charter (as defined below) in substantially the form attached hereto as Exhibit C (the “ Charter Amendment ”).

3. The Schedule of Purchasers attached to the Purchase Agreement is hereby replaced in its entirety with the Schedule of Purchasers attached hereto as Exhibit A .

4. Except as expressly amended by this Amendment, the Purchase Agreement shall remain in full force and effect without change.

5. This Amendment may be executed in any number of counterparts, each of which when executed and delivered shall be an original, but all of which together shall constitute one and the same instrument.

[signature pages follow]

I N W ITNESS W HEREOF , the parties have executed this A MENDMENT as of the date first written above.


COMPANY:		PURCHASERS:

ARCA BIOPHARMA , I NC .		S KYLINE V ENTURE P ARTNERS Q UALIFIED P URCHASER F UND IV, L.P.

Signature:	/s/ Christopher D. Ozeroff	By:	Skyline Venture Management IV, LLC
Print Name:	Christopher D. Ozeroff		Its General Partner
Title:	Executive Vice President Business Development and General Counsel	By:	/s/ John G. Freund
			John G Freund, Managing Director

		I NTER W EST P ARTNERS IX, LP

		By:	InterWest Management Partners IX, LLC

		By:	/s/ Linda Grais
			Linda Grais, Venture Member

		A TLAS V ENTURE F UND VII, L.P.

		By:	Atlas Venture Associates VII, L.P.
			its General Partner

		By:	Atlas Venture Associates VII, Inc.
			its General Partner

		Signature:	/s/ Kristen Laguerre
		Print Name:	Kristen Laguerre
		Title:	Vice President

FIRST AMENDMENT TO NOTE AND WARRANT PURCHASE AGREEMENT

SIGNATURE PAGE


						B OULDER V ENTURES IV, L.P.

						By:		BV Partners IV, L.L.C., its General Partner

						Signature:		/s/ Kyle Lefkoff
						Print Name:		Kyle Lefkoff
						Title:		Managing Member

						B OULDER V ENTURES IV (A NNEX ), L.P.

						By:		BV Partners IV, L.L.C., its General Partner

						Signature:		/s/ Kyle Lefkoff
						Print Name:		Kyle Lefkoff
						Title:		Managing Member

						T HE P EIERLS F OUNDATION , I NC .

						Signature:		/s/ E. Jeffrey Peierls
						Print Name:		E. Jeffrey Peierls
						Title:		President

						N UVELO , I NC .

						Signature:		/s/ Lee Bendekgey
						Print Name:		Lee Bendekgey
						Title:		Sr. VP, CFO and General Counsel

FIRST AMENDMENT TO NOTE AND WARRANT PURCHASE AGREEMENT

SIGNATURE PAGE

SCHEDULE OF PURCHASERS


N AME AND A DDRESS	L OAN A MOUNT		W ARRANT C ONSIDERATION		T OTAL P URCHASE P RICE
S KYLINE V ENTURE P ARTNERS Q UALIFIED P URCHASER F UND IV, L.P.	$	1,742,362	$	83,334	$	1,825,696
525 University Ave Suite 520 Palo Alto, CA 94301 Attention: Kerry Kenny Facsimile: (650) 329-1090

I NTER W EST P ARTNERS IX, LP	$	1,395,144	$	66,728	$	1,461,872
2710 Sand Hill Road Second Floor Menlo Park, CA 94025 Attention: Linda Grais Facsimile: (650) 854-4706

A TLAS V ENTURE F UND VII, L.P.	$	3,506,900	$	167,730	$	3,674,630
890 Winter Street, Suite 320 Waltham, MA 02451 Attention: General Counsel Facsimile: (781) 622-1701

B OULDER V ENTURES IV, L.P.	$	88,176	$	4,217	$	92,393
1900 Ninth Street, Suite 200 Boulder, CO 80302 Attention: Kyle Lefkoff Facsimile: (303) 444-0267

B OULDER V ENTURES IV (A NNEX ), L.P.	$	1,331,715	$	63,694	$	1,395,409
1900 Ninth Street, Suite 200 Boulder, CO 80302 Attention: Kyle Lefkoff Facsimile: (303) 444-0267

T HE P EIERLS F OUNDATION , I NC .	$	286,306	$	13,694	$	300,000
c/o U.S. Trust Company of N.Y. 114 West 47 ^th Street New York, NY 10036 Attention: Mr. John Kennedy

T OTAL	$	8,350,603.00	$	399,397.00	$	8,750,000.00

Exhibit 10.34

ARCA BIOPHARMA, INC.

STOCK OPTION AGREEMENT

Optionee:

Date of Grant:

ARCA biopharma, Inc. (f/k/a Nuvelo, Inc.) has granted to the individual (the “ Optionee ” ) named in the Notice of Grant of Stock Option (the “ Notice ” ) to which this Stock Option Agreement (the “ Option Agreement ” ) is attached an option (the “ Option ” ) to purchase certain shares of Stock upon the terms and conditions set forth in the Notice and this Option Agreement. The Option has been granted pursuant to and shall in all respects be subject to the terms and conditions of the Nuvelo, Inc. 2004 Equity Incentive Plan (the “ Plan ” ), as amended to the Date of Option Grant, the provisions of which are incorporated herein by reference. By signing the Notice, the Optionee: (a) represents that the Optionee has read and is familiar with the terms and conditions of the Notice, the Plan and this Option Agreement, including the Effect of Termination of Service set forth in Section 7, (b) accepts the Option subject to all of the terms and conditions of the Notice, the Plan and this Option Agreement, (c) agrees to accept as binding, conclusive and final all decisions or interpretations of the Board upon any questions arising under the Notice, the Plan or this Option Agreement, and (d) acknowledges receipt of a copy of the Notice, the Plan and this Option Agreement.

D EFINITIONS A ND C ONSTRUCTION .

1.1 Definitions . Unless otherwise defined herein, capitalized terms shall have the meanings assigned to such terms in the Notice or the Plan.

1.2 Construction . Captions and titles contained herein are for convenience only and shall not affect the meaning or interpretation of any provision of this Option Agreement. Except when otherwise indicated by the context, the singular shall include the plural and the plural shall include the singular. Use of the term “or” is not intended to be exclusive, unless the context clearly requires otherwise.

T AX C ONSEQUENCES .

2.1 Tax Status of Option . This Option is intended to have the tax status designated in the Notice.

(a) Incentive Stock Option . If the Notice so designates, this Option is intended to be an Incentive Stock Option within the meaning of Section 422(b) of the Code, but the Company does not represent or warrant that this Option qualifies as such. The Optionee should consult with the Optionee’s own tax advisor regarding the tax effects of this Option and the requirements necessary to obtain favorable income tax treatment under Section 422 of the Code, including, but not limited to, holding period requirements. (NOTE TO OPTIONEE: If the Option is exercised more than three (3) months after the date on which you cease to be an Employee (other than by reason of your death or permanent and total disability as defined in Section 22(e)(3) of the Code), the Option will be treated as a Nonstatutory Stock Option and not as an Incentive Stock Option to the extent required by Section 422 of the Code.)

(b) Nonstatutory Stock Option. If the Notice so designates, this Option is intended to be a Nonstatutory Stock Option and shall not be treated as an Incentive Stock Option within the meaning of Section 422(b) of the Code.

2.2 ISO Fair Market Value Limitation. If the Notice designates this Option as an Incentive Stock Option , then to the extent that the Option (together with all Incentive Stock Options granted to the Optionee under all stock option plans of the Participating Company Group, including the Plan) becomes exercisable for the first time during any calendar year for shares having a Fair Market Value greater than One Hundred Thousand Dollars ($100,000), the portion of such options which exceeds such amount will be treated as Nonstatutory Stock Options. For purposes of this Section 2.2, options designated as Incentive Stock Options are taken into account in the order in which they were granted, and the Fair Market Value of stock is determined as of the time the option with respect to such stock is granted. If the Code is amended to provide for a different limitation from that set forth in this Section 2.2, such different limitation shall be deemed incorporated herein effective as of the date required or permitted by such amendment to the Code. If the Option is treated as an Incentive Stock Option in part and as a Nonstatutory Stock Option in part by reason of the limitation set forth in this Section 2.2, the Optionee may designate which portion of such Option the Optionee is exercising. In the absence of such designation, the Optionee shall be deemed to have exercised the Incentive Stock Option portion of the Option first. Separate certificates representing each such portion shall be issued upon the exercise of the Option. (NOTE TO OPTIONEE: If the aggregate Exercise Price of the Option (that is, the Exercise Price multiplied by the Number of Option Shares) plus the aggregate exercise price of any other Incentive Stock Options you hold (whether granted pursuant to the Plan or any other stock option plan of the Participating Company Group) is greater than $100,000, you should contact the Chief Financial Officer of the Company to ascertain whether the entire Option qualifies as an Incentive Stock Option.)

A DMINISTRATION .

All questions of interpretation concerning this Option Agreement shall be determined by the Board. All determinations by the Board shall be final and binding upon all persons having an interest in the Option. Any officer of a Participating Company shall have the authority to act on behalf of the Company with respect to any matter, right, obligation, or election which is the responsibility of or which is allocated to the Company herein, provided the officer has apparent authority with respect to such matter, right, obligation, or election.

E XERCISE OF THE O PTION .

4.1 Right to Exercise. Except as otherwise provided herein, the Option shall be exercisable on and after the Date of Option Grant (or if later, the Optionee’s Service commencement date) and prior to the termination of the Option (as provided in Section 6) in an amount not to exceed (a) the number of Option Shares that have vested in accordance with the vesting provisions set forth in the Notice and this Option Agreement, minus (b) the number of Option Shares previously acquired upon exercise of the Option.

4.2 Method of Exercise . Exercise of the Option shall be by written notice to the Company which must state the election to exercise the Option, the number of whole shares of Stock for which the Option is being exercised and such other representations and agreements as to the Optionee’s investment intent with respect to such shares as may be required pursuant to the provisions of this Option Agreement. The written notice must be signed by the Optionee and must be delivered in person, by certified or registered mail, return receipt requested, by confirmed facsimile transmission, or by such other means as the Company may permit, to the Chief Financial Officer of the Company, or other authorized representative of the Participating Company Group, prior to the termination of the Option as set forth in Section 6, accompanied by full payment of the aggregate Exercise Price for the number of shares of Stock being purchased. The Option shall be deemed to be exercised upon receipt by the Company of such written notice and the aggregate Exercise Price.

4.3 Payment of Exercise Price.

(a) Forms of Consideration Authorized . Except as otherwise provided below, payment of the aggregate Exercise Price for the number of shares of Stock for which the Option is being exercised shall be made (i) in cash, by check, or cash equivalent, (ii) by tender to the Company, or attestation to the ownership, of whole shares of Stock owned by the Optionee having a Fair Market Value (as determined by the Company without regard to any restrictions on transferability applicable to such stock by reason of federal or state securities laws or agreements with an underwriter for the Company) not less than the aggregate Exercise Price, (iii) by means of a Cashless Exercise, as defined in Section 4.3(b), or (iv) by any combination of the foregoing.

(b) Limitations on Forms of Consideration.

(i) Tender of Stock. Notwithstanding the foregoing, the Option may not be exercised by tender to the Company, or attestation to the ownership, of shares of Stock to the extent such tender or attestation would constitute a violation of the provisions of any law, regulation or agreement restricting the redemption of the Company’s stock. The Option may not be exercised by tender to the Company, or attestation to the ownership, of shares of Stock unless such shares either have been owned by the Optionee for more than six (6) months or were not acquired, directly or indirectly, from the Company.

(ii) Cashless Exercise. A “ Cashless Exercise ” means the delivery of a properly executed notice together with irrevocable instructions to a broker in a form acceptable to the Company providing for the assignment to the Company of the proceeds of a sale or loan with respect to some or all of the shares of Stock acquired upon the exercise of the Option pursuant to a program or procedure approved by the Company (including, without limitation, through an exercise complying with the provisions of Regulation T as promulgated from time to time by the Board of Governors of the Federal Reserve System). The Company reserves, at any and all times, the right, in the Company’s sole and absolute discretion, to decline to approve or terminate any such program or procedure.

4.4 Tax Withholding . At the time the Option is exercised, in whole or in part, or at any time thereafter as requested by the Company, the Optionee hereby authorizes

withholding from payroll and any other amounts payable to the Optionee, and otherwise agrees to make adequate provision for (including by means of a Cashless Exercise to the extent permitted by the Company), any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Participating Company Group, if any, which arise in connection with the Option, including, without limitation, obligations arising upon (a) the exercise, in whole or in part, of the Option, (b) the transfer, in whole or in part, of any shares acquired upon exercise of the Option, (c) the operation of any law or regulation providing for the imputation of interest, or (d) the lapsing of any restriction with respect to any shares acquired upon exercise of the Option. The Company shall have no obligation to deliver shares of Stock until the tax withholding obligations of the Participating Company Group have been satisfied by the Optionee.

4.5 Certificate Registration . Except in the event the Exercise Price is paid by means of a Cashless Exercise, the certificate for the shares as to which the Option is exercised shall be registered in the name of the Optionee, or, if applicable, in the names of the heirs of the Optionee.

4.6 Restrictions on Grant of the Option and Issuance of Shares . The grant of the Option and the issuance of shares of Stock upon exercise of the Option shall be subject to compliance with all applicable requirements of federal, state or foreign law with respect to such securities. The Option may not be exercised if the issuance of shares of Stock upon exercise would constitute a violation of any applicable federal, state or foreign securities laws or other law or regulations or the requirements of any stock exchange or market system upon which the Stock may then be listed. In addition, the Option may not be exercised unless (a) a registration statement under the Securities Act shall at the time of exercise of the Option be in effect with respect to the shares issuable upon exercise of the Option or (b) in the opinion of legal counsel to the Company, the shares issuable upon exercise of the Option may be issued in accordance with the terms of an applicable exemption from the registration requirements of the Securities Act. THE OPTIONEE IS CAUTIONED THAT THE OPTION MAY NOT BE EXERCISED UNLESS THE FOREGOING CONDITIONS ARE SATISFIED. ACCORDINGLY, THE OPTIONEE MAY NOT BE ABLE TO EXERCISE THE OPTION WHEN DESIRED EVEN THOUGH THE OPTION IS VESTED. The inability of the Company to obtain from any regulatory body having jurisdiction the authority, if any, deemed by the Company’s legal counsel to be necessary to the lawful issuance and sale of any shares subject to the Option shall relieve the Company of any liability in respect of the failure to issue or sell such shares as to which such requisite authority shall not have been obtained. As a condition to the exercise of the Option, the Company may require the Optionee to satisfy any qualifications that may be necessary or appropriate, to evidence compliance with any applicable law or regulation and to make any representation or warranty with respect thereto as may be requested by the Company.

4.7 Fractional Shares . The Company shall not be required to issue fractional shares upon the exercise of the Option.

T RANSFERABILITY OF THE O PTION .

The Option may generally only be exercised during the lifetime of the Optionee only by the Optionee or the Optionee’s guardian or legal representative and may not be exercised, assigned or transferred in any manner except by will, by the laws of descent and distribution, or as otherwise provided in the Plan. Following the death of the Optionee, the Option, to the extent provided in Section 7, may be exercised by the Optionee’s legal representative or by any person empowered to do so under the deceased Optionee’s will or under the then applicable laws of descent and distribution.

T ERMINATION OF THE O PTION .

The Option shall terminate and may no longer be exercised on the first to occur of (a) the Option Expiration Date, (b) the last date for exercising the Option following termination of the Optionee’s Service as described in Section 7, or (c) a Change in Control to the extent provided in Section 8.

E FFECT OF T ERMINATION OF S ERVICE .

7.1 Option Exercisability.

(a) Disability . If the Optionee’s Service with the Participating Company Group terminates because of the Disability of the Optionee, the Option, to the extent unexercised and exercisable on the date on which the Optionee’s Service terminated, may be exercised by the Optionee (or the Optionee’s guardian or legal representative) at any time prior to the expiration of twelve (12) months after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date.

(b) Death . If the Optionee’s Service with the Participating Company Group terminates because of the death of the Optionee, the Option, to the extent unexercised and exercisable on the date on which the Optionee’s Service terminated, may be exercised by the Optionee’s legal representative or other person who acquired the right to exercise the Option by reason of the Optionee’s death at any time prior to the expiration of twelve (12) months after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date. The Optionee’s Service shall be deemed to have terminated on account of death if the Optionee dies within three (3) months after the Optionee’s termination of Service.

(c) Other Termination of Service . If the Optionee’s Service with the Participating Company Group terminates for any reason, except Disability or death, the Option, to the extent unexercised and exercisable by the Optionee on the date on which the Optionee’s Service terminated, may be exercised by the Optionee at any time prior to the expiration of three (3) months (or such other longer period of time as determined by the Board, in its discretion) after the date on which the Optionee’s Service terminated, but in any event no later than the Option Expiration Date.

7.2 Extension if Exercise Prevented by Law . Notwithstanding the foregoing, if the exercise of the Option within the applicable time periods set forth in Section 7.1

is prevented by the provisions of Section 4.6, the Option shall remain exercisable until three (3) months after the date the Optionee is notified by the Company that the Option is exercisable, but in any event no later than the Option Expiration Date.

7.3 Extension if Optionee Subject to Section 16(b). Notwithstanding the foregoing, if a sale within the applicable time periods set forth in Section 7.1 of shares acquired upon the exercise of the Option would subject the Optionee to suit under Section 16(b) of the Exchange Act, the Option shall remain exercisable until the earliest to occur of (a) the tenth (10th) day following the date on which a sale of such shares by the Optionee would no longer be subject to such suit, (b) the one hundred and ninetieth (190th) day after the Optionee’s termination of Service, or (c) the Option Expiration Date.

7.4 Extension if Exercise Prevented by Lock-Up Agreement. Notwithstanding the foregoing, if the exercise of the Option within any portion of the applicable time period set forth in Section 7.1(c) is prevented by the provisions of lock-up agreement between the Optionee and an underwriter of any of securities issued by the Company, the Option shall remain exercisable until three (3) months after the expiration of the term of any such lock-up agreement, but in any event no later than the Option Expiration Date.

C HANGE IN C ONTROL .

(a) In the event of a Change in Control, the Option may be subject to acceleration of exercisability and vesting in accordance with the terms of this Option Agreement and the Plan, and the Acquiring Corporation may either assume the Company’s rights and obligations under the Option or substitute for the Option a substantially equivalent option for the Acquiring Corporation’s stock. The Option shall terminate and cease to be outstanding effective as of the date of the Change in Control to the extent that the Option is neither assumed or substituted for by the Acquiring Corporation in connection with the Change in Control nor exercised as of the date of the Change in Control. Notwithstanding the foregoing, shares acquired upon exercise of the Option prior to the Change in Control and any consideration received pursuant to the Change in Control with respect to such shares shall continue to be subject to all applicable provisions of this Option Agreement except as otherwise provided herein.

(b) If a Change in Control occurs prior to expiration of the Option and at a time when the Optionee remains in Service as an employee of any Participating Group Company, then fifty percent (50%) of Optionee’s unvested Option Shares shall become fully and immediately vested upon the closing date of such Change in Control (to the extent such Option Shares have not yet then vested), and any remaining unvested Option Shares shall continue to vest according to the vesting schedule set forth herein; provided, however , that on the earlier to occur of (i) the one (1) year anniversary of the closing date of such Change in Control and (ii) the Optionee’s Involuntary Termination Date (as defined below), any Option Shares that remain unvested on such earlier date shall become fully and immediately vested (provided further, that, in the case of clause (i), the Optionee remains in continuous Service as an employee during such one (1) year period). The Optionee will experience an “ Involuntary Termination Date ” on the Optionee’s employment termination date if his or her Service is terminated by the Company or its successor without Cause (as defined below) or by him or her for Good Reason (as defined below).

(c) For purposes of this Option Agreement, “ Cause ” means that the Optionee has committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of any contract between the Optionee and the Company; and, “ Good Reason ” means (x) the relocation of the Optionee’s normal principal place of work greater than thirty (30) miles from the Optionee’s then current normal work location; (y) a decrease in the Optionee’s then current base salary of more than fifteen percent (15%), other than any such decrease resulting from a general reduction by the Company in the base salary of all similarly situated employees; or (z) the Company unilaterally makes significant detrimental reductions in the Optionee’s job responsibilities; provided, that the Optionee shall give written notice to the Chairman of the Company’s Board setting forth his or her intent to resign for Good Reason and the facts in support of his or her claim that Good Reason exists; and the Company shall have twenty (20) days after the applicable party has received such notice to take such actions, if any, as the Company may deem appropriate to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred). If the Company so acts to eliminate such claimed Good Reason, then the Optionee shall not be deemed to be resigning for Good Reason under such facts.

A DJUSTMENTS FOR C HANGES IN C APITAL S TRUCTURE .

In the event of any stock dividend, stock split, reverse stock split, recapitalization, combination, reclassification, or similar change in the capital structure of the Company, appropriate adjustments shall be made in the number, Exercise Price and class of shares of stock subject to the Option. If a majority of the shares which are of the same class as the shares that are subject to the Option are exchanged for, converted into, or otherwise become (whether or not pursuant to an Ownership Change Event) shares of another corporation (the “ New Shares ” ), the Board may unilaterally amend the Option to provide that the Option is exercisable for New Shares. In the event of any such amendment, the Number of Option Shares and the Exercise Price shall be adjusted in a fair and equitable manner, as determined by the Board, in its discretion. Notwithstanding the foregoing, any fractional share resulting from an adjustment pursuant to this Section 9 shall be rounded down to the nearest whole number, and in no event may the Exercise Price be decreased to an amount less than the par value, if any, of the stock subject to the Option. The adjustments determined by the Board pursuant to this Section 9 shall be final, binding and conclusive.

10.

R IGHTS AS A S TOCKHOLDER , E MPLOYEE OR C ONSULTANT .

dividends, distributions or other rights for which the record date is prior to the date such certificate is issued, except as provided in Section 9. If the Optionee is an Employee, the Optionee understands and acknowledges that, except as otherwise provided in a separate, written employment agreement between a Participating Company and the Optionee, the Optionee’s employment is “at will” and is for no specified term. Nothing in this Option Agreement shall confer upon the Optionee any right to continue in the Service of a Participating Company or interfere in any way with any right of the Participating Company Group to terminate the Optionee’s Service as an Employee or Consultant, as the case may be, at any time.

11.

N OTICE OF S ALES U PON D ISQUALIFYING D ISPOSITION .

The Optionee shall dispose of the shares acquired pursuant to the Option only in accordance with the provisions of this Option Agreement. In addition, if the Notice designates this Option as an Incentive Stock Option, the Optionee shall (a) promptly notify the Chief Financial Officer of the Company if the Optionee disposes of any of the shares acquired pursuant to the Option within one (1) year after the date the Optionee exercises all or part of the Option or within two (2) years after the Date of Option Grant and (b) provide the Company with a description of the circumstances of such disposition. Until such time as the Optionee disposes of such shares in a manner consistent with the provisions of this Option Agreement, unless otherwise expressly authorized by the Company, the Optionee shall hold all shares acquired pursuant to the Option in the Optionee’s name (and not in the name of any nominee) for the one-year period immediately after the exercise of the Option and the two-year period immediately after Date of Option Grant. At any time during the one-year or two-year periods set forth above, the Company may place a legend on any certificate representing shares acquired pursuant to the Option requesting the transfer agent for the Company’s stock to notify the Company of any such transfers. The obligation of the Optionee to notify the Company of any such transfer shall continue notwithstanding that a legend has been placed on the certificate pursuant to the preceding sentence.

12.

L EGENDS .

The Company may at any time place legends referencing any applicable federal, state or foreign securities law restrictions, and, if applicable, that the shares were acquired upon exercise of an Incentive Stock Option on all certificates representing shares of stock subject to the provisions of this Option Agreement. The Optionee shall, at the request of the Company, promptly present to the Company any and all certificates representing shares acquired pursuant to the Option in the possession of the Optionee in order to carry out the provisions of this Section.

13.

L OCK -U P A GREEMENT .

as may be established by the underwriter for such public offering; provided, however, that such period of time shall not exceed one hundred eighty (180) days from the effective date of the registration statement to be filed in connection with such public offering (or such longer period, not to exceed eighteen (18) days after the expiration of the one hundred eighty (180) day period, as the underwriters or the Company shall request in order to facilitate compliance with NASD Rule 2711). The foregoing limitation shall not apply to shares registered in the public offering under the Securities Act. The Optionee further agrees to execute and deliver such other agreements as may be reasonably requested by the Company and/or the underwriter(s) that are consistent with the foregoing or that are necessary to give further effect thereto. In order to enforce the foregoing covenant, the Company may impose stop-transfer instructions with respect to any shares of stock of the Company or any rights to acquire stock of the Company held by the Optionee until the end of such period.

14.

R ESTRICTIONS ON T RANSFER OF S HARES .

No shares acquired upon exercise of the Option may be sold, exchanged, transferred (including, without limitation, any transfer to a nominee or agent of the Optionee), assigned, pledged, hypothecated or otherwise disposed of, including by operation of law, in any manner which violates any of the provisions of this Option Agreement, and any such attempted disposition shall be void. The Company shall not be required (a) to transfer on its books any shares which will have been transferred in violation of any of the provisions set forth in this Option Agreement or (b) to treat as owner of such shares or to accord the right to vote as such owner or to pay dividends to any transferee to whom such shares will have been so transferred.

15.

M ISCELLANEOUS P ROVISIONS .

15.1 Termination for Cause. If the Optionee’s Service is terminated for Cause, then the Optionee shall immediately forfeit all rights to the Option and the Option, including any vested portion, shall immediately expire.

15.2 Binding Effect. Subject to the restrictions on transfer set forth herein, this Option Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective heirs, executors, administrators, successors and assigns.

15.3 Termination or Amendment. The Board may terminate or amend the Plan or the Option at any time; provided, however, that except as provided in Section 8 in connection with a Change in Control, no such termination or amendment may adversely affect the Option or any unexercised portion hereof without the consent of the Optionee unless such termination or amendment is necessary to comply with any applicable law or government regulation or is required to enable the Option, if designated an Incentive Stock Option in the Notice, to qualify as an Incentive Stock Option. No amendment or addition to this Option Agreement shall be effective unless in writing.

fees prepaid, addressed to the other party at the address shown below that party’s signature on the Notice or at such other address as such party may designate in writing from time to time to the other party.

15.5 Integrated Agreement. The Notice, this Option Agreement and the Plan constitute the entire understanding and agreement of the Optionee and the Participating Company Group with respect to the subject matter contained herein or therein and supersedes any prior agreements, understandings, restrictions, representations, or warranties among the Optionee and the Participating Company Group with respect to such subject matter other than those as set forth or provided for herein or therein. To the extent contemplated herein or therein, the provisions of the Notice and the Option Agreement shall survive any exercise of the Option and shall remain in full force and effect.

15.6 Applicable Law. This Option Agreement shall be governed by the laws of the State of Delaware as such laws are applied to agreements between Delaware residents entered into and to be performed entirely within the State of Delaware.

15.7 Counterparts. The Notice may be executed in counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.


¨ Incentive Stock Option				Optionee:



¨ Nonstatutory Stock Option				Date:

STOCK OPTION EXERCISE NOTICE

ARCA biopharma, Inc.

Attention: Chief Financial Officer

8001 Arista Place, Suite 200

Broomfield, CO 80021

Ladies and Gentlemen:

1. Option . I was granted an option (the “ Option ”) to purchase shares of the common stock (the “ Option Shares ”) of ARCA biopharma, Inc. (the “ Company ”) pursuant to the Nuvelo, Inc. 2004 Equity Incentive Plan, as amended to date (the “ Plan ”), my Notice of Grant of Stock Option (the “ Notice ”) and my Stock Option Agreement (the “ Option Agreement ”) as follows:


Grant Number:

Date of Option Grant:

Number of Option Shares:

Exercise Price per Option Share:		$

2. Exercise of Option . I hereby elect to exercise the Option to purchase the following number of Option Shares:


Total Option Shares Purchased:

Total Exercise Price (Total Shares X Price per Option Share)		$

3. Payments . I enclose payment in full of the total exercise price for the Option Shares in the following form(s), as authorized by my Option Agreement.


¨ Cash:

¨ Check:

¨ Tender of Company Stock:		Contact Plan Administrator

¨ Cashless exercise:		Contact Plan Administrator

4. Tax Withholding . Subject to the Option Agreement, I authorize payroll withholding and otherwise will make adequate provision for the federal, state, local and foreign tax withholding obligations of the Company, if any, in connection with the Option.

5. Optionee Information .


My address is:



My Social Security Number is:

6. Notice of Disqualifying Disposition . If the Option is an Incentive Stock Option, I agree that I will promptly notify the Chief Financial Officer of the Company if I transfer any of the Option Shares within one (1) year from the date I exercise all or part of the Option or within two (2) years of the Date of Option Grant.

7. Binding Effect . I agree that the Option Shares are being acquired in accordance with and subject to the terms, provisions and conditions of the Option Agreement, to all of which I hereby expressly assent. This agreement shall inure to the benefit of and be binding upon my heirs, executors, administrators, successors and assigns.

I understand that I am purchasing the Option Shares pursuant to the terms of the Plan, the Notice and my Option Agreement, copies of which I have received and carefully read and understand.

Very truly yours,

(Signature)

Receipt of the above is hereby acknowledged.


ARCA biopharma, Inc.

By:
Title:
Dated:

Exhibit 10.35

ARCA BIOPHARMA, INC.

STOCK OPTION AGREEMENT

Optionee:

Date of Grant:

D EFINITIONS AND C ONSTRUCTION .

1.1 Definitions . Unless otherwise defined herein, capitalized terms shall have the meanings assigned to such terms in the Notice or the Plan.

T AX C ONSEQUENCES .

2.1 Tax Status of Option . This Option is intended to have the tax status designated in the Notice.

2.2 ISO Fair Market Value Limitation. If the Notice designates this Option as an Incentive Stock Option, then to the extent that the Option (together with all Incentive Stock Options granted to the Optionee under all stock option plans of the Participating Company Group, including the Plan) becomes exercisable for the first time during any calendar year for shares having a Fair Market Value greater than One Hundred Thousand Dollars ($100,000), the portion of such options which exceeds such amount will be treated as Nonstatutory Stock Options. For purposes of this Section 2.2, options designated as Incentive Stock Options are taken into account in the order in which they were granted, and the Fair Market Value of stock is determined as of the time the option with respect to such stock is granted. If the Code is amended to provide for a different limitation from that set forth in this Section 2.2, such different limitation shall be deemed incorporated herein effective as of the date required or permitted by such amendment to the Code. If the Option is treated as an Incentive Stock Option in part and as a Nonstatutory Stock Option in part by reason of the limitation set forth in this Section 2.2, the Optionee may designate which portion of such Option the Optionee is exercising. In the absence of such designation, the Optionee shall be deemed to have exercised the Incentive Stock Option portion of the Option first. Separate certificates representing each such portion shall be issued upon the exercise of the Option. (NOTE TO OPTIONEE: If the aggregate Exercise Price of the Option (that is, the Exercise Price multiplied by the Number of Option Shares) plus the aggregate exercise price of any other Incentive Stock Options you hold (whether granted pursuant to the Plan or any other stock option plan of the Participating Company Group) is greater than $100,000, you should contact the Chief Financial Officer of the Company to ascertain whether the entire Option qualifies as an Incentive Stock Option.)

A DMINISTRATION .

E XERCISE OF THE O PTION .

4.2 Method of Exercise . Exercise of the Option shall be by written notice to the Company which must state the election to exercise the Option, the number of whole shares of

Stock for which the Option is being exercised and such other representations and agreements as to the Optionee’s investment intent with respect to such shares as may be required pursuant to the provisions of this Option Agreement. The written notice must be signed by the Optionee and must be delivered in person, by certified or registered mail, return receipt requested, by confirmed facsimile transmission, or by such other means as the Company may permit, to the Chief Financial Officer of the Company, or other authorized representative of the Participating Company Group, prior to the termination of the Option as set forth in Section 6, accompanied by full payment of the aggregate Exercise Price for the number of shares of Stock being purchased. The Option shall be deemed to be exercised upon receipt by the Company of such written notice and the aggregate Exercise Price.

4.3 Payment of Exercise Price.

(b) Limitations on Forms of Consideration.

permitted by the Company), any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Participating Company Group, if any, which arise in connection with the Option, including, without limitation, obligations arising upon (a) the exercise, in whole or in part, of the Option, (b) the transfer, in whole or in part, of any shares acquired upon exercise of the Option, (c) the operation of any law or regulation providing for the imputation of interest, or (d) the lapsing of any restriction with respect to any shares acquired upon exercise of the Option. The Company shall have no obligation to deliver shares of Stock until the tax withholding obligations of the Participating Company Group have been satisfied by the Optionee.

4.7 Fractional Shares . The Company shall not be required to issue fractional shares upon the exercise of the Option.

T RANSFERABILITY OF THE O PTION .

Option, to the extent provided in Section 7, may be exercised by the Optionee’s legal representative or by any person empowered to do so under the deceased Optionee’s will or under the then applicable laws of descent and distribution.

T ERMINATION OF THE O PTION .

E FFECT OF T ERMINATION OF S ERVICE .

7.1 Option Exercisability.

7.2 Extension if Exercise Prevented by Law . Notwithstanding the foregoing, if the exercise of the Option within the applicable time periods set forth in Section 7.1 is prevented by the provisions of Section 4.6, the Option shall remain exercisable until three (3) months after the date the Optionee is notified by the Company that the Option is exercisable, but in any event no later than the Option Expiration Date.

Exchange Act, the Option shall remain exercisable until the earliest to occur of (a) the tenth (10th) day following the date on which a sale of such shares by the Optionee would no longer be subject to such suit, (b) the one hundred and ninetieth (190th) day after the Optionee’s termination of Service, or (c) the Option Expiration Date.

C HANGE IN C ONTROL .

In the event of a Change in Control, the Option may be subject to acceleration of exercisability and vesting in accordance with the terms of the Plan, and the Acquiring Corporation may either assume the Company’s rights and obligations under the Option or substitute for the Option a substantially equivalent option for the Acquiring Corporation’s stock. The Option shall terminate and cease to be outstanding effective as of the date of the Change in Control to the extent that the Option is neither assumed or substituted for by the Acquiring Corporation in connection with the Change in Control nor exercised as of the date of the Change in Control. Notwithstanding the foregoing, shares acquired upon exercise of the Option prior to the Change in Control and any consideration received pursuant to the Change in Control with respect to such shares shall continue to be subject to all applicable provisions of this Option Agreement except as otherwise provided herein.

A DJUSTMENTS FOR C HANGES IN C APITAL S TRUCTURE .

10.

R IGHTS AS A S TOCKHOLDER , E MPLOYEE OR C ONSULTANT .

The Optionee shall have no rights as a stockholder with respect to any shares covered by the Option until the date of the issuance of a certificate for the shares for which the

Option has been exercised (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company). No adjustment shall be made for dividends, distributions or other rights for which the record date is prior to the date such certificate is issued, except as provided in Section 9. If the Optionee is an Employee, the Optionee understands and acknowledges that, except as otherwise provided in a separate, written employment agreement between a Participating Company and the Optionee, the Optionee’s employment is “at will” and is for no specified term. Nothing in this Option Agreement shall confer upon the Optionee any right to continue in the Service of a Participating Company or interfere in any way with any right of the Participating Company Group to terminate the Optionee’s Service as an Employee or Consultant, as the case may be, at any time.

11.

N OTICE OF S ALES U PON D ISQUALIFYING D ISPOSITION .

12.

L EGENDS .

13.

L OCK -U P A GREEMENT .

otherwise dispose of any shares of stock of the Company or any rights to acquire stock of the Company for such period of time from and after the effective date of such registration statement as may be established by the underwriter for such public offering; provided, however, that such period of time shall not exceed one hundred eighty (180) days from the effective date of the registration statement to be filed in connection with such public offering (or such longer period, not to exceed eighteen (18) days after the expiration of the one hundred eighty (180) day period, as the underwriters or the Company shall request in order to facilitate compliance with NASD Rule 2711). The foregoing limitation shall not apply to shares registered in the public offering under the Securities Act. The Optionee further agrees to execute and deliver such other agreements as may be reasonably requested by the Company and/or the underwriter(s) that are consistent with the foregoing or that are necessary to give further effect thereto. In order to enforce the foregoing covenant, the Company may impose stop-transfer instructions with respect to any shares of stock of the Company or any rights to acquire stock of the Company held by the Optionee until the end of such period.

14.

R ESTRICTIONS ON T RANSFER OF S HARES .

15.

M ISCELLANEOUS P ROVISIONS .

15.1 Termination for Cause. If the Optionee’s Service is terminated for Cause (as defined below), then the Optionee shall immediately forfeit all rights to the Option and the Option, including any vested portion, shall immediately expire. For purposes of this Option Agreement, “ Cause ” means that the Optionee has committed or engaged in: (a) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (b) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (c) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of any contract between the Optionee and the Company.

regulation or is required to enable the Option, if designated an Incentive Stock Option in the Notice, to qualify as an Incentive Stock Option. No amendment or addition to this Option Agreement shall be effective unless in writing.

15.4 Notices. Any notice required or permitted hereunder shall be given in writing and shall be deemed effectively given (except to the extent that this Option Agreement provides for effectiveness only upon actual receipt of such notice) upon personal delivery or upon deposit in the United States Post Office, by registered or certified mail, with postage and fees prepaid, addressed to the other party at the address shown below that party’s signature on the Notice or at such other address as such party may designate in writing from time to time to the other party.

15.7 Counterparts. The Notice may be executed in counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.


¨ Incentive Stock Option				Optionee:



¨ Nonstatutory Stock Option				Date:

STOCK OPTION EXERCISE NOTICE

ARCA biopharma, Inc.

Attention: Chief Financial Officer

8001 Arista Place, Suite 200

Broomfield, CO 80021

Ladies and Gentlemen:


Grant Number:

Date of Option Grant:

Number of Option Shares:

Exercise Price per Option Share:		$

2. Exercise of Option . I hereby elect to exercise the Option to purchase the following number of Option Shares:


Total Option Shares Purchased:

Total Exercise Price (Total Shares X Price per Option Share)		$

3. Payments . I enclose payment in full of the total exercise price for the Option Shares in the following form(s), as authorized by my Option Agreement.


¨ Cash:

¨ Check:

¨ Tender of Company Stock:		Contact Plan Administrator

¨ Cashless exercise:		Contact Plan Administrator

5. Optionee Information .


My address is:



My Social Security Number is:

I understand that I am purchasing the Option Shares pursuant to the terms of the Plan, the Notice and my Option Agreement, copies of which I have received and carefully read and understand.

Very truly yours,

(Signature)

Receipt of the above is hereby acknowledged.


ARCA biopharma, Inc.

By:
Title:
Dated:

Exhibit 10.36

ARCA BIOPHARMA, INC.

STOCK OPTION AGREEMENT


Optionee:


Date of Grant:

1. D EFINITIONS A ND C ONSTRUCTION .

1.1 Definitions . Unless otherwise defined herein, capitalized terms shall have the meanings assigned to such terms in the Notice or the Plan.

2. T AX C ONSEQUENCES .

2.1 Tax Status of Option . This Option is intended to have the tax status designated in the Notice.

3. A DMINISTRATION .

4. E XERCISE OF THE O PTION .

4.3 Payment of Exercise Price.

(b) Limitations on Forms of Consideration.

4.4 Tax Withholding . At the time the Option is exercised, in whole or in part, or at any time thereafter as requested by the Company, the Optionee hereby authorizes withholding from payroll and any other amounts payable to the Optionee, and otherwise agrees to make adequate provision for (including by means of a Cashless Exercise to the extent permitted by the Company), any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Participating Company Group, if any, which arise in connection with the Option, including, without limitation, obligations arising upon (a) the exercise, in whole or in part, of the Option, (b) the transfer, in whole or in part, of any shares acquired upon exercise of the Option, (c) the operation of any law or regulation providing for the imputation of interest, or (d) the lapsing of any restriction with respect to any shares acquired upon exercise of the Option. The Company shall have no obligation to deliver shares of Stock until the tax withholding obligations of the Participating Company Group have been satisfied by the Optionee.

4.7 Fractional Shares . The Company shall not be required to issue fractional shares upon the exercise of the Option.

5. T RANSFERABILITY OF THE O PTION .

6. T ERMINATION OF THE O PTION .

7. E FFECT OF T ERMINATION OF S ERVICE .

7.1 Option Exercisability.

8. C HANGE IN C ONTROL .

(b) If (i) a Change in Control occurs prior to expiration of the Option and (ii) Optionee’s Service as a Director of the Company terminates in connection with or at anytime following the Change in Control (for whatever reason), then one hundred percent (100%) of Optionee’s unvested Option Shares shall become fully and immediately vested on the date that Optionee ceases to be a Director of the Company (to the extent such Option Shares have not yet then vested).

9. A DJUSTMENTS FOR C HANGES IN C APITAL S TRUCTURE .

10. R IGHTS AS A S TOCKHOLDER , E MPLOYEE OR C ONSULTANT .

The Optionee shall have no rights as a stockholder with respect to any shares covered by the Option until the date of the issuance of a certificate for the shares for which the Option has been exercised (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company). No adjustment shall be made for dividends, distributions or other rights for which the record date is prior to the date such certificate is issued, except as provided in Section 9. If the Optionee is an Employee, the Optionee understands and acknowledges that, except as otherwise provided in a separate, written employment agreement between a Participating Company and the Optionee, the Optionee’s employment is “at will” and is for no specified term. Nothing in this Option Agreement shall confer upon the Optionee any right to continue in the Service of a Participating Company or interfere in any way with any right of the Participating Company Group to terminate the Optionee’s Service as an Employee or Consultant, as the case may be, at any time.

11. N OTICE OF S ALES U PON D ISQUALIFYING D ISPOSITION .

the Company may place a legend on any certificate representing shares acquired pursuant to the Option requesting the transfer agent for the Company’s stock to notify the Company of any such transfers. The obligation of the Optionee to notify the Company of any such transfer shall continue notwithstanding that a legend has been placed on the certificate pursuant to the preceding sentence.

12. L EGENDS .

13. L OCK -U P A GREEMENT .

The Optionee hereby agrees that in the event of any underwritten public offering of stock, including an initial public offering of stock, made by the Company pursuant to an effective registration statement filed under the Securities Act, the Optionee shall not offer, sell, contract to sell, pledge, hypothecate, grant any option to purchase or make any short sale of, or otherwise dispose of any shares of stock of the Company or any rights to acquire stock of the Company for such period of time from and after the effective date of such registration statement as may be established by the underwriter for such public offering; provided, however, that such period of time shall not exceed one hundred eighty (180) days from the effective date of the registration statement to be filed in connection with such public offering (or such longer period, not to exceed eighteen (18) days after the expiration of the one hundred eighty (180) day period, as the underwriters or the Company shall request in order to facilitate compliance with NASD Rule 2711). The foregoing limitation shall not apply to shares registered in the public offering under the Securities Act. The Optionee further agrees to execute and deliver such other agreements as may be reasonably requested by the Company and/or the underwriter(s) that are consistent with the foregoing or that are necessary to give further effect thereto. In order to enforce the foregoing covenant, the Company may impose stop-transfer instructions with respect to any shares of stock of the Company or any rights to acquire stock of the Company held by the Optionee until the end of such period.

14. R ESTRICTIONS ON T RANSFER OF S HARES .

15. M ISCELLANEOUS P ROVISIONS .

15.1 Termination for Cause. If the Optionee’s Service is terminated for Cause (as defined below), then the Optionee shall immediately forfeit all rights to the Option and the Option, including any vested portion, shall immediately expire. For purposes of this Option Agreement, “ Cause ” means that the Optionee has committed or engaged in: (a) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; or (b) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of any contract between the Optionee and the Company.

15.7 Counterparts. The Notice may be executed in counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.


¨ Incentive Stock Option				Optionee:



¨ Nonstatutory Stock Option				Date:

STOCK OPTION EXERCISE NOTICE

ARCA biopharma, Inc.

Attention: Chief Financial Officer

8001 Arista Place, Suite 200

Broomfield, CO 80021

Ladies and Gentlemen:


Grant Number:

Date of Option Grant:

Number of Option Shares:

Exercise Price per Option Share:		$

2. Exercise of Option . I hereby elect to exercise the Option to purchase the following number of Option Shares:


Total Option Shares Purchased:

Total Exercise Price (Total Shares X Price per Option Share)		$

3. Payments . I enclose payment in full of the total exercise price for the Option Shares in the following form(s), as authorized by my Option Agreement.


¨ Cash:

¨ Check:

¨ Tender of Company Stock:		Contact Plan Administrator

¨ Cashless exercise:		Contact Plan Administrator

5. Optionee Information .


My address is:



My Social Security Number is:

I understand that I am purchasing the Option Shares pursuant to the terms of the Plan, the Notice and my Option Agreement, copies of which I have received and carefully read and understand.

Very truly yours,

(Signature)

Receipt of the above is hereby acknowledged.


ARCA biopharma, Inc.

By:
Title:
Dated:

Exhibit 10.37

ARCA biopharma, Inc.

NOTICE OF GRANT OF STOCK OPTION

[ ] (the “Optionee”) has been granted an option (the “Option”) to purchase certain shares of Stock of ARCA biopharma, Inc. (f/k/a Nuvelo, Inc.) pursuant to the Nuvelo, Inc. 2004 Equity Incentive Plan, as amended to date (as amended, the “Plan”), as follows:


Date of Option Grant:		[ , 2009]
Option Number:		[ ]
Number of Option Shares:		[ ]
Exercise Price:		[$ per share]
Vesting Start Date:		[ ]
Option Expiration Date:		[ , 2019]
Tax Status of Option:		Incentive Stock Option

The total Exercise Price of the Option Shares granted is [$ ].

The Optionee’s right to purchase the Option Shares vests as follows: (i) 25% of the Option Shares vests one year after the Vesting Start Date, provided the Optionee remains in Service at the end of such one-year period, and (ii) 6.25% of the Option Shares vests at the end of each three-month period thereafter, provided the Optionee remains in Service at the end of each such period. The resulting aggregate number of vested Option Shares will be rounded to the nearest whole number, and the Optionee cannot vest in more than the number of Option Shares.

By their signatures below, the Company and the Optionee agree that the Option is governed by this Notice of Grant of Stock Option and by the provisions of the Plan and the attached Stock Option Agreement, both of which are attached to and made a part of this document. The Optionee acknowledges receipt of copies of the Plan and the Stock Option Agreement, represents that the Optionee has read and is familiar with their provisions, and hereby accepts the Option subject to all of their terms and conditions.


ARCA biopharma, Inc.						OPTIONEE

By:
						Signature

Its:
						Date



Address:	8001 Arista Place, Suite 200
	Broomfield, CO 80021	Address:



ATTACHMENTS:		Stock Option Agreement and Exercise Notice (in hard or soft copy).

Exhibit 10.38

ARCA biopharma, Inc.

NOTICE OF GRANT OF STOCK OPTION


Date of Option Grant:		[ , 2009]
Option Number:		[ ]
Number of Option Shares:		[ ]
Exercise Price:		[$ per share]
Vesting Start Date:		[ ]
Option Expiration Date:		[ , 2019]
Tax Status of Option:		Non-Qualified Stock Option

The total Exercise Price of the Option Shares granted is [$ ].

The Optionee’s right to purchase the Option Shares vests as follows: (i) one-twenty fourth (1/24 ^th ) of the Option Shares vests on the one-month anniversary of the Vesting Start Date, provided the Optionee remains in Service at the end of such one-month period, and (ii) one-twenty fourth (1/24 ^th ) of the Option Shares vests monthly thereafter over the next twenty three (23) months, provided the Optionee remains in Service at the end of each such period. The resulting aggregate number of vested Option Shares will be rounded to the nearest whole number, and the Optionee cannot vest in more than the number of Option Shares.


ARCA biopharma, Inc.						OPTIONEE

By:
						Signature

Its:
						Date



Address:	8001 Arista Place, Suite 200
	Broomfield, CO 80021	Address:



ATTACHMENTS:		Stock Option Agreement and Exercise Notice (in hard or soft copy).

Exhibit 10.43

LOGO

June 1, 2008

VIA HAND DELIVERY

Dr. Michael R. Bristow

5 Blackmer Road

Englewood, Colorado 80110

Re:	Amended and Restated Employment and Retention Agreement

Dear Mike:

ARCA biopharma, Inc. (the “Company” ) is pleased to offer you the following agreement regarding your employment as the Company’s Chairman and Chief Science and Medical Officer and certain severance benefits (the “Agreement” ). This Agreement amends, supersedes and terminates any and all prior agreements with respect to your employment terms and severance benefits, including but not limited to, that certain Offer Letter and Letter Agreement dated January 1, 2005; provided, however, that, except as otherwise expressly provided, the Employee Intellectual Property Agreement (as defined below) is not modified or terminated hereby, and shall continue in full force and effect.

1. Employment . The Company hereby agrees to employ you and you hereby accept such employment upon the terms and conditions set forth herein and agree to perform such duties as are commensurate with your office as prescribed by the Board of Directors of the Company.

2. Duties. You shall render exclusive, full-time services to the Company, except as allowed below, as its Chairman and Chief Science and Medical Officer and shall report to the Company’s Chief Executive Officer. Your responsibilities, title, working conditions, duties, reporting relationship and/or any other aspect of your employment may be changed, added to or eliminated during your employment at the sole discretion of the Company. During the term of your employment hereunder, you shall devote your best efforts and your full business time, skill and attention to the performance of your duties on behalf of the Company. The Company will permit you to continue to perform academic work for UCHSC and for the CVI, as well as to continue performing work for Myogen, Inc.; provided that such work does not interfere with your duties as Chief Science and Medical Officer, or conflict with the interests of the Company; and further provided, that the Board of Directors may review the impact of your outside activities on your duties as Chief Science and Medical Officer at any time.

3. Compensation . For all services rendered and to be rendered hereunder, and for the other agreements by you contained herein, the Company agrees to pay you, and you agree to accept a salary of $16,666.67 per month. Such salary will be subject to review and adjustment

on an annual basis in accordance with the procedures set forth by the Company’s Board of Directors or Compensation Committee of the Board of Directors. Any such salary shall be payable pursuant to the Company’s payroll procedures which may be changed by the Company from time to time and shall be subject to such deductions or withholdings as the Company is required to make pursuant to law, or by further agreement with you. In addition to your base salary, you may be eligible to receive a bonus pursuant to an employee bonus plan as approved by the Board of Directors in its sole discretion. You will also be eligible to participate in the Company’s benefit plans based on the eligibility criteria for each of those plans as they become available, which plans will remain subject to change from time to time at the Company’s discretion.

4. Termination. You and the Company each acknowledge that your employment relationship with the Company is at-will and that either party has the right to terminate your employment with the Company at any time for any reason whatsoever, with or without cause or advance notice pursuant to the following provisions.

(a) Termination by Death or Disability. In the event you shall die during the period of your employment hereunder or become permanently disabled, which shall mean you are unable to perform each of the essential duties of your position by reason of a medically determinable physical or mental impairment which is potentially permanent in character or which can be expected to last for a continuous period of not less than twelve (12) months, your employment and the Company’s obligation to make payments hereunder shall terminate on the date of your death, or the date upon which, in the sole reasonable determination of the Board of Directors, you are determined to be permanently disabled. The Company’s ability to terminate you as a result of any disability shall be to the extent permitted by state and/or federal law.

(b) Voluntary Resignation. In the event you voluntarily resign from your employment with the Company (other than for Good Reason as defined below), the Company’s obligation to make payments hereunder shall cease upon such resignation, and you shall not be entitled to any severance pay, accelerated vesting, pay in lieu of notice or any other such compensation, except the Company shall pay you (i) any salary earned but unpaid prior to the resignation and all accrued but unused vacation, (ii) if applicable, all commissions rightfully earned prior to your resignation and (iii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the date of resignation. Vesting of any of your stock options outstanding on the date of resignation shall cease on the date of resignation.

(c) Termination for Cause. In the event you are terminated by the Company for Cause (as defined below), the Company’s obligation to make payments hereunder shall cease upon the date of receipt by you of written notice and explanation of such termination (the “Date of Termination” ), and you shall not be entitled to any severance pay, accelerated vesting, pay in lieu of notice or any other such compensation, except the Company shall pay you (i) any salary earned but unpaid prior to the Date of Termination and all accrued but unused vacation, (ii) if applicable, all commissions rightfully earned prior to the Date of Termination and (iii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the Date of Termination. Vesting of any stock options outstanding on the Date of Termination shall cease on the Date of Termination.

(d) Termination by the Company Without Cause or Resignation for Good Reason. Subject to the terms and conditions of this Agreement, the Company will provide you with Severance Benefits (as defined below) if (i) the Company terminates your employment without Cause or (ii) you resign your employment for Good Reason. You will not be entitled to receive any Severance Benefits if (A) the Company terminates your employment for Cause, (B) you resign from your employment with the Company other than for Good Reason, (C) in the event of your death or permanent disability, or (D) your employment is terminated because of the Company’s insolvency prior to the closing of a preferred stock financing of the Company resulting in gross proceeds to the Company of at least $3,000,000. In addition, to the extent that any federal, state or local laws, including, without limitation, so-called “plant closing” laws, require the Company to give advance notice or make a payment of any kind to you because of your involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change of control, or any other similar event or reason, the Severance Benefits payable under this Agreement shall either be reduced proportionately or eliminated, such that the total amounts paid to you do not exceed the amounts specified herein. The Severance Benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of your involuntary termination of employment for the foregoing reasons.

5. Description of Severance Benefits. For purposes of this Agreement, “Severance Benefits” are defined as:

(a) severance pay (the “Severance Pay” ) equivalent to: (A)(i) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of full-time employment with the Company if a Notice Date (as defined below) occurs (a) on the same day as a Corporate Transaction or (b) within thirteen (13) months after the effective date of a Corporate Transaction or (ii) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of full-time employment with the Company if a Corporate Transaction has not occurred on or before the Notice Date; and (B) a pro rata portion of any bonus compensation under any employee bonus plan that has been approved by the Board of Directors ( “Bonus Pay” ) payable to you for the fiscal year in which your employment terminated to be paid at the same time that such incentive bonus would have been paid if such termination had not occurred. Your pro rata portion of any Bonus Pay shall be based upon the number of days in such calendar year elapsed through the Notice Date of such termination as a proportion of 365.

The date you are notified that your employment with the Company is being terminated without Cause or the date you notify the Company that you are terminating your employment for Good Reason, shall be referred to herein as the “Notice Date.” The Severance Pay shall be payable in equal installments over the applicable number of months (the “Initial Severance Period ”) in accordance with the Company’s then applicable payroll policies, beginning no earlier than seven (7) days after the effective date of the release described below, and will be subject to standard payroll deductions and withholdings; provided, however, that any Bonus Pay shall not be payable to you until such time as bonus compensation under the applicable employee bonus plan is paid to other employees of the Company; and

(b) reimbursement of your out-of-pocket costs to continue your group health insurance benefits (and dependent coverage, if applicable) under COBRA at substantially the same level of coverage in effect immediately prior to the Notice Date for (i) twelve (12) months, if Severance Pay is payable pursuant to paragraph 5(a)(A)(i) above, or (ii) twelve (12) months, if Severance Pay is payable pursuant to paragraph 5(a)(A)(ii) above, following the last day of the month in which your Notice Date occurs, payable at the sole discretion of the Company either in advance on the first day of each month or in a single lump sum, whether or not you elect or are eligible to receive COBRA; provided , that even if you do not elect or are not eligible to receive COBRA, you shall receive the equivalent of such out-of-pocket costs paid by you not to exceed the costs that such benefits would equal under COBRA if you were so eligible.

To receive any of the Severance Benefits, you must first sign and date a general release of claims in favor of the Company in the form attached hereto as Exhibit A (the “Release” ). Such Release shall not be signed or dated until the Notice Date, and, except as otherwise required by applicable law, is not valid (and will not entitle you to Severance Benefits) unless signed and delivered to the Company within three (3) days after such Notice Date.

(c) The Company may elect, in its sole discretion, to pay you the equivalent of up to twelve (12) months of your Base Salary in effect as of your last day of full-time employment with the Company, which additional payment shall extend your covenants and obligations set forth in Article IV of the Employee Intellectual Property, Confidentiality and Non-Compete Agreement for such additional period. If the Company elects to make such additional payment to you, the Company shall make such payments in equal installments over the applicable number of months following the Initial Severance Period in accordance with the Company’s then applicable payroll policies, or in the sole discretion of the Company as designated by the Company in writing within seven (7) days after the Notice Date, in a single lump sum cash payment, subject to standard payroll deductions and withholdings, and such additional amounts shall be deemed to be “Severance Pay” and to be part of the “Severance Benefits” for purposes of this Agreement.

6. Parachute Payments.

state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax basis, of the greatest amount of the Payment to you. If a reduction in payments or benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, reduction shall occur in the following order unless you elect in writing a different order ( provided, however, that such election shall be subject to Company approval if made on or after the date on which the event that triggers the Payment occurs): reduction of cash payments; cancellation of accelerated vesting of stock awards; reduction of employee benefits. In the event that acceleration of vesting of stock award compensation is to be reduced, such acceleration of vesting shall be cancelled in the reverse order of the date of grant of your stock awards unless you elect in writing a different order for cancellation.

(b) The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the event giving rise to the Payment ( “Payment Event” ) shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the Payment Event, the Board shall have the discretion to appoint a nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder.

(c) The accounting firm engaged to make the determinations hereunder shall provide its calculations, together with detailed supporting documentation, to the Company and you within fifteen (15) calendar days after the date on which your right to a Payment is triggered (if requested at that time by the Company or you) or such other time as requested by the Company or you. If the accounting firm determines that no Excise Tax is payable with respect to a Payment, either before or after the application of the Reduced Amount, it shall furnish the Company and you with an opinion reasonably acceptable to you that no Excise Tax will be imposed with respect to such Payment. The Company shall be entitled to rely upon the accounting firm’s determinations, which shall be final and binding.

7. Compliance with Revenue Code Section 409A. To the extent any Severance Benefits are paid from the date of termination of your employment through March 15 of the calendar year following such termination, such Severance Benefits are intended to constitute separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations and thus payable pursuant to the “short-term deferral” rule set forth in Section 1.409A-1(b)(4) of the Treasury Regulations; (b) are paid following said March 15, such Severance Benefits are intended to constitute separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations made upon an involuntary separation from service and payable pursuant to Section 1.409A-1(b)(9)(iii) of the Treasury Regulations, to the maximum extent permitted by said provision, and (c) are in excess of the amounts specified in clauses (a) and (b) of this paragraph, shall (unless otherwise exempt under Treasury Regulations) be considered separate payments subject to the distribution requirements of Section 409A(a)(2)(A) of the Code, including, without limitation, the requirement of Section 409A(a)(2)(B)(i) of the Code that payments or benefits be delayed until 6 months after your separation from service (if the Company is publicly traded and you are a “specified employee” within the meaning of the aforesaid section of the Code at the time of such separation from service). In the event that a six-month delay of any such separation payments or benefits is required, on the first regularly scheduled pay date following the

conclusion of the delay period you shall receive a lump sum payment or benefit in an amount equal to the separation payments and benefits that were so delayed, and any remaining separation payments or benefits shall be paid on the same basis and at the same time as otherwise specified pursuant to this Agreement (subject to applicable tax withholdings and deductions).

8. Description of Corporate Transaction. For purposes of this Agreement, “Corporate Transaction” is defined as: (i) a sale of all or substantially all of the assets of the Company; (ii) a merger, consolidation or reorganization involving the Company if, immediately after the consummation of such merger, consolidation or reorganization, the stockholders of the Company immediately prior thereto do not own, directly or indirectly, either (A) outstanding voting securities representing more than fifty percent (50%) of the combined outstanding voting power of the surviving entity in such merger, consolidation or reorganization or (B) more than fifty percent (50%) of the combined outstanding voting power of the parent of the surviving entity in such merger, consolidation or similar transaction; or (iii) any transaction (including without limitation a merger or reorganization in which the Company is the surviving entity) which results in any person or entity (other than persons who are stockholders or affiliates of the Company immediately prior to the transaction) owning fifty percent (50%) or more of the combined voting power of all classes of stock of the Company, other than the sale by the Company of stock in transactions the primary purpose of which is to raise capital for the Company’s operations and activities.

9. Salary and Accrued PTO/Vacation. On your last date of employment with the Company, the Company will pay to you all of your accrued salary and all of your accrued but unused paid time off (“PTO”) or vacation as the case may be earned through your last day of employment.

10. Definition of Base Salary. For purposes of this Agreement, “Base Salary” means your base salary in effect as of your last day of full-time employment with the Company, excluding the following: any type of commissions, incentive payments or any other similar remuneration paid directly to you, or any other income received in connection with stock options, contributions made by the Company under any employee benefit plan, or similar items of compensation.

11. Definition of Cause. For purposes of this Agreement, “Cause” means that you have committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of this Agreement or of your Employee Intellectual Property, Confidentiality and Non-Compete Agreement (a copy of which is attached hereto as Exhibit B ) (the “Employee Intellectual Property Agreement” ) or any other contract between you and the Company. In the event you are terminated for Cause you will not be entitled to the Severance Benefits, pay in lieu of notice, vesting of any shares under any option plan, vesting of any unrestricted shares, or any other such compensation set forth herein and you shall immediately forfeit all rights to any options to purchase shares of the Company’s common stock (including vested options) and such options shall immediately expire, but you will be entitled to all other compensation (including commissions rightfully earned), benefits and unreimbursed expenses accrued through the Date of Termination.

12. Definition of Good Reason. For purposes of this Agreement, “Good Reason” shall mean (i) the relocation of your normal principal place of work greater than thirty (30) miles from your then current normal work location; (ii) a decrease in your then current base salary of more than fifteen percent (15%), other than any such decrease resulting from a general reduction by the Company in the base salary of all Company executive officers; or (iii) the Company unilaterally makes significant detrimental reductions in your job responsibilities; provided, that you shall give written notice to the Chairman of the Company’s Board of Directors setting forth your intent to resign for Good Reason and the facts in support of your claim that Good Reason exists within ninety (90) days of the initial existence of any of the foregoing conditions; and the Company shall have thirty (30) days after the applicable party has received such notice to take such actions, if any, as the Company may deem appropriate to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred); and your final separation from service occurs within two (2) years of the initial existence of any of the foregoing conditions. If the Company acts to eliminate such claimed Good Reason within the thirty (30) day period after receipt of your notice, then you shall not be deemed to be resigning for Good Reason under such facts.

13. At-Will Employment. Nothing in this Agreement alters the at-will nature of your employment relationship with the Company. Any contrary representations or agreements, which may have been made to you, are superseded by this Agreement. Subject to the terms of this Agreement, either you or the Company may terminate your employment relationship at any time, with or without Cause or advance notice.

14. Employee Intellectual Property Agreement.

(a) Execution and Compliance. You acknowledge that you are a member of the Company’s executive and management personnel and that, as such, you have been and will be privy to extremely sensitive, confidential and valuable commercial information, which constitutes trade secrets of the Company, the disclosure of which would greatly harm the Company. Your work for the Company is conditioned on your execution of and continued compliance with the Employee Intellectual Property Agreement, which shall continue in full force and effect.

(b) Extension of Time. In the event that you breach any covenant, obligation or duty in the Employee Intellectual Property Agreement or its subparts, any such duty, obligation, or covenants to which you and the Company agreed by the Employee Intellectual Property Agreement and its subparts shall automatically toll from the date of the first breach, and all subsequent breaches, until the resolution of the breach through private settlement, judicial or other action, including all appeals. The duration and length of your duties and obligations as agreed by the Employee Intellectual Property Agreement and its subparts shall continue upon the effective date of any such settlement, or judicial or other resolution.

15. Miscellaneous. Except as specifically set forth herein, this Agreement constitutes the complete, final and exclusive embodiment of the entire agreement between you and the

Company with regard to your employment terms and Severance Benefits. It is entered into without reliance on any promise or representation, written or oral, other than those expressly contained herein, and it supersedes any other such promises, warranties or representations. This Agreement may not be modified or amended except in writing signed by you and a duly authorized officer of the Company. This Agreement will be deemed to have been entered into and will be construed and enforced in accordance with the laws of the State of Colorado as applied to contracts made and to be performed entirely within Colorado.

* * * * *

Please sign below to indicate your understanding and acceptance of this Agreement and return the signed original to me at your earliest convenience.


Very truly yours,

ARCA BIOPHARMA , I NC .

By:	/s/ Richard B. Brewer
Name:	Richard B. Brewer
Title:	President and CEO

U NDERSTOOD AND A GREED :

/s/ Dr. Michael R. Bristow		June 4, 2008
Dr. Michael R. Bristow		Date

E XHIBIT A

RELEASE

In exchange for the Severance Benefits provided under the foregoing Employment and Retention Agreement with ARCA biopharma, Inc. (the “Company” ), dated [ ], and except as set forth in this release, I hereby release, acquit and forever discharge the Company, its parents and subsidiaries, and their officers, directors, agents, servants, employees, shareholders, successors, assigns and affiliates, of and from any and all claims, liabilities, demands, causes of action, costs, expenses, attorneys fees, damages, indemnities and obligations of every kind and nature, in law, equity, or otherwise, known and unknown, suspected and unsuspected, disclosed and undisclosed (other than any claim for indemnification I may have as a result of any third party action against me based on my employment with the Company), arising out of or in any way related to agreements, events, acts or conduct at any time prior to the date I execute this release, including, but not limited to: all such claims and demands directly or indirectly arising out of or in any way connected with my employment with the Company or the termination of that employment, including but not limited to, claims of intentional and negligent infliction of emotional distress, any and all tort claims for personal injury, claims or demands related to salary, bonuses, commissions, stock, stock options, or any other ownership interests in the Company, vacation pay, fringe benefits, expense reimbursements, severance pay, or any other form of compensation; all claims for breach of contract and wrongful termination; claims pursuant to any federal, state or local law or cause of action including, but not limited to, the federal Civil Rights Act of 1964, as amended; the federal Employee Retirement Income Security Act of 1974, as amended; the federal Americans with Disabilities Act of 1990; Colorado anti-discrimination statutes, including the Colorado Civil Rights Act (as amended); tort law; contract law; wrongful discharge; discrimination; fraud; defamation; emotional distress; and breach of the implied covenant of good faith and fair dealing; provided, however, that nothing in this paragraph shall be construed in any way to release the Company from its existing obligations to indemnify me pursuant to any agreement or applicable law.

I also hereby acknowledge that I am knowingly and voluntarily waiving and releasing any rights I may have under the federal Age Discrimination in Employment Act of 1967, as amended ( “ADEA” ). I also acknowledge that the consideration given for the release in the preceding paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that:

(a)

my waiver and release do not apply to any rights or claims that arise on or after the date I execute this release;

(b)

I have the right to consult with an attorney prior to executing this release;

(c)

I have twenty-one (21) days to consider this release (although I may choose to voluntarily execute this release earlier);

(d)

I have seven (7) days following my execution of this release to revoke the release; and

(e)

this release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I execute this release.

This Release constitutes the complete, final and exclusive embodiment of the entire agreement between the Company and me with regard to the subject matter hereof. I am not relying on any promise or representation by the Company that is not expressly stated herein. This Release may only be modified by a writing signed by both me and a duly authorized officer of the Company. This Release will be deemed to have been entered into and will be construed and enforced in accordance with the laws of the State of Colorado as applied to contracts made and to be performed entirely within Colorado. This Release shall be effective on the date I sign and return it to the Company, provided that the Company has also signed it.

I accept and agree to the terms and conditions stated above.



Dr. Michael R. Bristow

Date:

ARCA BIOPHARMA , I NC .

By:
Name:
Title:

E XHIBIT B

EMPLOYEE INTELLECTUAL PROPERTY, CONFIDENTIALITY AND

NON-COMPETE AGREEMENT

[Omitted]

Exhibit 10.44

June 1, 2008

VIA HAND DELIVERY

Richard Brewer

5 Bird Hill Lane

Santa Cruz, CA 95060

Re: Amended and Restated Employment and Retention Agreement

Dear Dick:

ARCA biopharma, Inc. (the “ Company ”) is pleased to offer you the following agreement regarding your employment as the Company’s President and Chief Executive Officer and certain severance benefits (the “ Agreement ”). This Agreement amends, supersedes and terminates any and all prior agreements, representations or understandings with respect to your employment terms and severance benefits, including that certain letter agreement dated November 2, 2006.

1. Employment. The Company hereby agrees to employ you and you hereby accept such employment upon the terms and conditions set forth herein and agree to perform such duties as are commensurate with your office as prescribed by the Board of Directors of the Company. Your appointment to the Company’s Board of Directors at the inception of your employment shall be a condition to your employment under this Agreement. This Agreement shall become effective upon commencement of your employment with the Company, which shall occur on or before November 2, 2006 (the “ Start Date ”). You agree to tender your resignation as a director of the Company effective on the date your employment with the Company terminates for any reason.

2. Duties. You shall render services to the Company as its President and Chief Executive Officer and shall report to the Company’s Board of Directors. During the term of your employment hereunder, you shall devote to the Company so much of your business time, skill and attention as are reasonably required for the performance of your duties. The Company will permit you to continue to serve on a maximum of four outside corporate board of directors; provided that such service does not interfere with your duties as President and Chief Executive Officer, or conflict with your fiduciary obligations to the Company; and further provided, that the Board of Directors may review the impact of your outside activities on your duties to the Company at any time.

3. Compensation.

(a) For all services rendered and to be rendered hereunder, and for the other agreements by you contained herein, the Company agrees to pay you, and you agree to accept a salary of $25,000.00 per month, $300,000 annualized, payable bi-weekly. Your salary will be subject to review and adjustment on an annual basis in accordance with the procedures set forth by the Company’s Board of Directors or Compensation Committee of the Board of Directors. Any such salary shall be payable pursuant to the Company’s payroll procedures which may be changed by the Company from time to time and shall be subject to such deductions or withholdings as the Company is required to make pursuant to law, or by further agreement with you. In addition to your base salary, you may be eligible to receive a bonus pursuant to an employee bonus plan as approved by the Board of Directors in its sole discretion. You will also be eligible to participate in the Company’s benefit plans based on the eligibility criteria for each of those plans as they become available, which plans will remain subject to change from time to time at the Company’s discretion; provided, that you and the Company have agreed that you will maintain your own health insurance for yourself and your dependents and that you will not participate in any Company-provided or sponsored health insurance plan.

(b) At the first meeting of the Company’s Board of Directors on or after the Start Date you will be granted the option to purchase nine hundred, ninety two thousand (992,000) shares of the Company’s Common Stock (the “Initial Option”), such grant being equal to approximately eight percent (8%) of the outstanding securities of the Company on the date of grant, calculated on a fully diluted basis. The exercise price for the Initial Option shall be equal to the fair market value of the Company’s Common Stock at the time of grant as determined by the Company’s Board of Directors. The Initial Option shall be fully vested upon grant; provided, however, that a portion of any shares you purchase prior to the fourth anniversary of the Start Date by means of the exercise of the Initial Option may be subject to repurchase by the Company, at the price you paid for such shares, as set forth in subsection (d), below. The Initial Option will be subject to the terms and conditions of the Company’s 2004 Stock Incentive Plan (the “Plan”) in effect at the time of grant, and a Stock Option Agreement between you and the Company governing this grant. The Initial Option is contingent upon approval by the Company’s Board of Directors and your execution of the Stock Option Agreement.

(c) In addition to the Initial Option, at the first meeting of the Company’s Board of Directors after the Start Date you will be issued five hundred thousand (500,000) shares of the Company’s Common Stock (the “Restricted Stock”) upon payment by you of a per share purchase price equal to the fair market value of the Common Stock on the date of issuance as determined by the Company’s Board of Directors, which is currently $0.15 per share. The shares of Restricted Stock will be subject to repurchase rights of the Company with respect to unvested shares, and to the other terms and conditions set forth in a Restricted Stock Agreement between you and the Company, and of the Plan. The Restricted Stock Agreement will provide, among other things, that:

(i) Two hundred, fifty thousand (250,000) shares of the Restricted Stock shall vest, and the Company’s repurchase right shall lapse with respect to such shares, on the earlier of (A) if the Company’s common stock is listed on a

national exchange, then the date on which the average market capitalization of the Company, as reported by such exchange over the immediately preceding ten business days, is at least two hundred, fifty million dollars ($250,000,000), or (B) the closing date or effective date of a Corporate Transaction in which the total consideration paid by the acquirer in the Corporate Transaction is at least two hundred, fifty million dollars ($250,000,000);

(ii) Two hundred, fifty thousand (250,000) shares of the Restricted Stock shall vest, and the Company’s repurchase right shall lapse with respect to such shares, on the earlier of (A) if the Company’s common stock is listed on a national exchange, then the date on which the average market capitalization of the Company, as reported by such exchange over the immediately preceding ten business days, is at least five hundred million dollars ($500,000,000), or (B) the closing date or effective date of a Corporate Transaction in which the total consideration paid by the acquirer in the Corporate Transaction is at least five hundred million dollars ($500,000,000).

Upon issuance of the shares of Restricted Stock, you agree to enter into the Company’s Right of First Refusal and Co-Sale Agreement and Voting Agreement. Upon the termination of your employment with the Company for any reason, any shares of Restricted Stock held by you that have not vested shall be subject to repurchase by the Company. In addition, any shares of Restricted Stock that have not vested pursuant to the foregoing provisions on or prior to the ten year anniversary date of the date of issuance shall be subject to repurchase by the Company.

(d) In the event that either you voluntarily resign from the Company or your employment is terminated by the Company for “Cause” as defined in Section 4(c), or upon your death or disability as defined in Section 4(a) below (any of the foregoing being defined as a “Termination Event”), the Company shall have the right to repurchase shares previously purchased by you as the result of the exercise of options granted to you as Initial Option (the “Initial Option Shares”), at the price paid by you for such shares, as follows: Upon a Termination Event prior to the first anniversary of the Start Date, the Company shall have the right to repurchase seventy five percent (75%) of any Initial Option Shares, and after the first anniversary, the Company’s right to repurchase Initial Option Shares shall be reduced by six and one-quarter percent (6.25%) at the end of each subsequent quarter. The Company’s right to repurchase shares purchased by you as the result of your exercise of any portion of the Initial Option shall lapse upon the earlier of a “Corporate Transaction” as defined below or upon your termination by the Company other than for “Cause” or for death or disability (including, without limitation, termination by you for “Good Reason” as defined below).

(e) The Initial Option shall, to the maximum extent permitted by law, be considered an Incentive Stock Option.

(f) For as long as you remain employed by the Company, the Company will reimburse you for the reasonable additional travel and housing expenses that you and

your spouse incur as a result of commuting from California or other U.S. location outside Colorado to the Company’s offices in Colorado, and also for the reasonable Company business travel expenses that you incur, such reimbursements in total not to exceed five hundred thousand dollars ($500,000) during each year period, beginning from the Start Date, that you remain employed under this Agreement. You agree to provide reasonable documentation of these expenses.

4. Termination. Subject to the terms and conditions of this letter agreement, you and the Company each acknowledge that your employment relationship with the Company is at-will and that either party has the right to terminate your employment with the Company at any time for any reason whatsoever, with or without cause or advance notice pursuant to the following provisions:

(a) Termination by Death or Disability. In the event you shall die during the period of your employment hereunder or become permanently disabled, which shall mean you are unable to perform each of the essential duties of your position by reason of a medically determined physical or mental impairment which is permanent or which lasts for a continuous period of not less than twelve (12) months, your employment and the Company’s obligation to make payments hereunder shall terminate on the date of your death, or the date upon which, in the reasonable determination of the Board of Directors, you are determined to be permanently disabled. The Company’s ability to terminate you as a result of any disability shall be to the extent permitted by state and/or federal law.

(b) Voluntary Resignation. In the event you voluntarily resign from your employment with the Company (other than for Good Reason as defined below), the Company’s obligation to make payments hereunder shall cease upon such resignation, and you shall not be entitled to any severance pay, accelerated vesting, pay in lieu of notice or any other such compensation, except the Company shall pay you (i) any salary earned but unpaid prior to the resignation and all accrued but unused vacation, and (ii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the date of resignation.

(c) Termination for Cause. In the event you are terminated by the Company for Cause (as defined below), the Company’s obligation to make payments hereunder shall cease upon the date of receipt by you of written notice and explanation of such termination (the “ Date of Termination ”), and you shall not be entitled to any severance pay, pay in lieu of notice or any other such compensation, except the Company shall pay you: (i) any salary earned but unpaid prior to the Date of Termination and all accrued but unused vacation, and (ii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the Date of Termination.

(d) Termination by the Company Without Cause or Resignation for Good Reason . Subject to the terms and conditions of this Agreement, the Company will provide you with Severance Benefits (as defined below) if (i) the Company terminates your employment without Cause or (ii) you resign your employment for Good Reason. You will not be entitled to receive any Severance Benefits if (A) the Company terminates

your employment for Cause, (B) you resign from your employment with the Company other than for Good Reason, or (C) in the event of your death or permanent disability. In addition, to the extent that any federal, state or local laws, including, without limitation, so-called “plant closing” laws, require the Company to give advance notice or make a payment of any kind to you because of your involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change of control, or any other similar event or reason, the Severance Benefits payable under this Agreement shall either be reduced proportionately or eliminated, such that the total amounts paid to you do not exceed the amounts specified herein. The Severance Benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of your involuntary termination of employment for the foregoing reasons.

5. Description of Severance Benefits. For purposes of this Agreement, “ Severance Benefits ” are defined as:

(a) Severance pay (the “ Severance Pay ”) equivalent to: (A) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of employment with the Company in accordance with this Agreement (i) if a Notice Date (as defined below) occurs (a) on the same day as a Corporate Transaction or (b) within thirteen (13) months after the effective date of a Corporate Transaction or (ii) if a Corporate Transaction has not occurred on or before the Notice Date; and (B) a pro rata portion of any bonus compensation under any employee bonus plan that has been approved by the Board of Directors (“ Bonus Pay ”) payable to you for the fiscal year in which your employment terminated to be paid at the same time that such incentive bonus would have been paid if such termination has not occurred. Your pro rata portion of any Bonus Pay shall be based upon the number of days in such calendar year elapsed through the Notice Date so such termination as a proportion of 365.

The date you are notified that your employment with the Company is being terminated without Cause or the date you notify the Company that you are terminating your employment for Good Reason, shall be referred to herein as the “ Notice Date .” The Severance Pay shall be payable in equal installments over the applicable number of months (the “ Initial Severance Period ”) in accordance with the Company’s then applicable payroll policies, beginning no earlier than seven (7) days after the effective date of the release described below, and will be subject to standard payroll deductions and withholdings; provided, however , that any Bonus Pay shall not be payable to you until such time as bonus compensation under the applicable employee bonus plan is paid to other employees of the Company.

To receive any of the Severance Benefits, you must first sign and date a general release of claims in favor of the Company in the form attached hereto as Exhibit A (the “ Release ”). Such Release shall not be signed or dated until the Notice Date, and, except as otherwise required by applicable law, is not valid (and will not entitle you to Severance Benefits) unless signed and delivered to the Company within three (3) days after such Notice Date.

(b) The Company may elect, in its sole discretion, to pay you the equivalent of up to twelve (12) months of your Base Salary in effect as of your last day of employment with the Company in accordance with this Agreement, which additional payment shall extend your covenants and obligations set forth in Article IV of the Employee Intellectual Property, Confidentiality and Non-Compete Agreement for such additional period. If the Company elects to make such additional payment to you, the Company shall make such payments in equal installments over the applicable number of months following the Initial Severance Period in accordance with the Company’s then applicable payroll policies, or in the sole discretion of the Company as designated by the Company in writing within seven (7) days after the Notice Date, in a single lump sum cash payment, subject to standard payroll deductions and withholdings, and such additional amounts shall be deemed to be “Severance Pay” and to be part of the “Severance Benefits” for purposes of this Agreement.

6. Parachute Payments.

(a) Notwithstanding anything in this Agreement to the contrary, if any payment or benefit you would receive pursuant to a Corporate Transaction from the Company or otherwise (“ Payment ”) (i) would constitute a “parachute payment” within the meaning of Section 280G of the Internal Revenue Code of 1986, as amended (the “ Code ”), and (ii) but for this sentence, would be subject to the excise tax imposed by Section 4999 of the Code (the “ Excise Tax ”), then such Payment shall be equal to the Reduced Amount (as defined below). For the avoidance of doubt, a Payment shall not be considered a parachute payment for purposes of this paragraph if such Payment is approved by the shareholders of the Company in accordance with the procedures set forth in Sections 280G(b)(5)(A)(ii) and (B) of the Code and the regulations thereunder, and at the time of such shareholder approval, no stock of the Company is readily tradeable on an established securities market or otherwise (within the meaning of Section 280G(b)(5)(A)(ii)(I) of the Code) (“ 280G Shareholder Approval ”). The “ Reduced Amount ” shall be either (i) the largest portion of the Payment that would result in no portion of the Payment being subject to the Excise Tax, or (ii) the Payment or a portion thereof after payment of the applicable Excise Tax, whichever amount after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax bases, of the greatest amount of the Payment to you. If a reduction in payments or benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, reduction shall occur in the following order unless you elect in writing a different order ( provided, however , that such election shall be subject to Company approval if made on or after the date on which the event that triggers the Payment occurs): reduction of cash payments; reduction of employee benefits.

(b) The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the event giving rise to the Payment (“ Payment Event ”) shall perform the foregoing calculations. The Company shall bear all expenses with respect to the determination by such accounting firm required to be made hereunder.

voting power of the parent of the surviving entity in such merger, consolidation or similar transaction; or (iii) any transaction (including without limitation a merger or reorganization in which the Company is the surviving entity) which results in any person or entity (other than persons who are stockholders or affiliates of the Company immediately prior to the transaction) owning fifty percent (50%) or more of the combined voting power of all classes of stock of the Company, other than the sale by the Company of stock in transactions the primary purpose of which is to raise capital for the Company’s operations and activities.

10. Definition of Base Salary. For purposes of this Agreement, “ Base Salary ” means your base salary in effect as of your last day of full-time employment with the Company, excluding the following: any type of commissions, incentive payments or any other similar remuneration paid directly to you, or any other income received in connection with stock options, contribution made by the Company under any employee benefit plan, or similar items of compensation.

11. Definition of Cause. For purposes of this Agreement, “ Cause ” means that you have committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of the fiduciary duty, violation of any duty of loyalty, or material breach of any material term of this Agreement or of your Employee Intellectual Property, Confidentiality and Non-Compete Agreement (a copy of which is attached hereto as Exhibit B ) (the “ Employee Intellectual Property Agreement ”) or any other contract between you and the Company. In the event you are terminated for Cause you will not be entitled to the Severance Benefits, pay in lieu of notice, vesting of any shares under any option plan, vesting of any unrestricted shares, or any other such compensation set forth herein and you shall immediately forfeit all rights to any options to purchase shares of the Company’s common stock (including vested options) and such options shall immediately expire, but you will be entitled to all other compensation (including commissions rightfully earned), benefits and unreimbursed expenses accrued through the Date of Termination.

12. Definition of Good Reason. For purposes of this Agreement, “ Good Reason ” shall mean (i) a material decrease in your then current base salary other than any such decrease resulting from a general reduction by the Company in the base salary of all Company executive officers; (ii) a material diminution in your authority or your reporting relationship (i.e., from the Board of Directors to an officer), (iii) failure of the Company’s shareholders to elect you to the Board of Directors of the Company, (iv) a move of the Company’s headquarters of more than 60 miles from its current location in Denver, Colorado, (v) resignation on your part within 90 days after a Corporate

Transaction, or (vi) the Company unilaterally makes significant detrimental reductions in your job responsibilities; provided , that you shall give written notice to the Chairman of the Company’s Board of Directors setting forth your intent to resign for Good Reason and the facts in support of your claim that Good Reason exists within ninety (90) days of the initial existence of any of the foregoing conditions; and the Company shall have thirty (30) days after the applicable party has received such notice to take such action, if any, as the Company may deem appropriate to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred); and your final separation from service occurs within two (2) years of the initial existence of any of the foregoing conditions. If the Company acts to eliminate such claimed Good Reason within the thirty (30) day period after receipt of your notice, then you shall not be deemed to be resigning for Good Reason under such facts.

14. Employee Intellectual Property Agreement.

(b) Extension of Time. In the event that you breach any covenant, obligation or duty in the Employee Intellectual Property Agreement or its subparts, any such duty, obligation or covenants to which you and the Company agreed by the Employee Intellectual Property Agreement and its subparts shall automatically toll from the date of the first breach, and all subsequent breaches, until the resolution of the breach through private settlement, judicial or other action, including all appeals. The duration and length of your duties and obligations as agreed by the Employee Intellectual Property Agreement and its subparts shall continue upon the effective date of any such settlement, or judicial or other resolution.

15. Miscellaneous. Except as specifically set forth herein, this Agreement and the Employee Intellectual Property Agreement constitute the complete, final and exclusive embodiment of the entire agreement between you and the Company with regard to your employment terms and Severance Benefits. This Agreement and the Employee Intellectual Property Agreement are entered into without reliance on any promise or representation, written or oral, or other than those expressly contained herein and therein, and supersede any other such promises, warranties or representations. This Agreement

may not be modified or amended except in writing signed by you and a duly authorized officer of the Company. This Agreement will be deemed to have been entered into and will be construed and enforced in accordance with the laws of the State of Colorado as applied to contracts made and to be performed entirely within Colorado.

Please sign below to indicate your understanding and acceptance of this Agreement and return the signed original to me at your earliest convenience.


Very truly yours,

ARCA biopharma, Inc.

By:	/s/ Michael Bristow, M.D.
Name:	Michael Bristow, M.D.
Title:	Chairman and Chief Science and Medical Officer

Understood and Agreed:

/s/ Richard Brewer		July 7, 2008
Richard Brewer		Date

E XHIBIT A

RELEASE

In exchange for the Severance Benefits provided under the foregoing Employment and Retention Agreement with ARCA biopharma, Inc. (the “ Company ”), dated [ ], and except as set forth in this release, I hereby release, acquit and forever discharge the Company, its parents and subsidiaries, and their officers, directors, agents, servants, employees, shareholders, successors, assigns and affiliates, of and from any and all claims, liabilities, demands, causes of action, costs, expenses, attorneys fees, damages, indemnities and obligations of every kind and nature, in law, equity, or otherwise, known and unknown, suspected and unsuspected, disclosed and undisclosed (other than any claim for indemnification I may have as a result of any third party action against me based on my employment with the Company), arising out of or in any way related to agreements, events, acts or conduct at any time prior to the date I execute this release, including, but not limited to: all such claims and demands directly or indirectly arising out of or in any way connected with my employment with the Company or the termination of that employment, including but not limited to, claims of intentional and negligent infliction of emotional distress, any and all tort claims for personal injury, claims or demands related to salary, bonuses, commissions, stock, stock options, or any other ownership interests in the Company, vacation pay, fringe benefits, expense reimbursements, severance pay, or any other form of compensation; all claims for breach of contract and wrongful termination; claims pursuant to any federal, state or local law or cause of action including, but not limited to, the federal Civil Rights Act of 1964, as amended; the federal Employee Retirement Income Security Act of 1974, as amended; the federal Americans with Disabilities Act of 1990; Colorado anti-discrimination statutes, including the Colorado Civil Rights Act (as amended); tort law; contract law; wrongful discharge; discrimination; fraud; defamation; emotional distress; and breach of the implied covenant of good faith and fair dealing; provided, however, that nothing in this paragraph shall be construed in any way to release the Company from its existing obligations to indemnify me pursuant to any agreement or applicable law.

I also hereby acknowledge that I am knowingly and voluntarily waiving and releasing any rights I may have under the federal Age Discrimination in Employment Act of 1967, as amended (“ ADEA ”). I also acknowledge that the consideration given for the release in the preceding paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that:

(a) my waiver and release do not apply to any rights or claims that arise on or after the date I execute this release;

(b) I have the right to consult with an attorney prior to executing this release;

(c) I have twenty-one (21) days to consider this release (although I may choose to voluntarily execute this release earlier);

(d) I have seven (7) days following my execution of this release to revoke the release; and

(e) this release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I execute this release.

This Release constitutes the complete, final and exclusive embodiment of the entire agreement between the Company and me with regard to the subject matter hereof. I am not relying on any promise or representation by the Company that is not expressly stated herein. This Release may only be modified by a writing signed by both me and a duly authorized officer of the Company. This Release will be deemed to have been entered into and will be construed and enforced in accordance with the laws of the State of Colorado as applied to contracts made and to be performed entirely within Colorado. This Release shall be effective on the date set forth in paragraph (e) above, provided that the Company has also signed it.

I accept and agree to the terms and conditions stated above.



[Name]

Date:

ARCA BIOPHARMA , I NC .

By:
Name:
Title:

E XHIBIT B

EMPLOYEE INTELLECTUAL PROPERTY, CONFIDENTIALITY AND NON-COMPETE AGREEMENT

[Omitted]

Exhibit 10.45

LOGO

June 1, 2008

VIA HAND DELIVERY

Christopher D. Ozeroff

1200 17 ^th Street, Suite 620

Denver, CO 80202

Re:	Amended and Restated Employment and Retention Agreement

Dear Chris:

ARCA biopharma, Inc. (the “ Company ”) is pleased to offer you the following agreement regarding your employment as the Company’s Executive Vice President Business Development and General Counsel and certain severance benefits (the “ Agreement ”). This Agreement amends, supersedes and terminates any and all prior agreements with respect to your employment terms and severance benefits, including but not limited to, that certain Offer Letter and Letter Agreement dated January 1, 2005; provided , however , that, except as otherwise expressly provided, the Employee Intellectual Property Agreement (as defined below) is not modified or terminated hereby, and shall continue in full force and effect.

2. Duties. You shall render exclusive, full-time services to the Company as its Executive Vice President Business Development and General Counsel and shall report to the Company’s Chief Business and Financial Officer. Your responsibilities, title, working conditions, duties, reporting relationship and/or any other aspect of your employment may be changed, added to or eliminated during your employment at the sole discretion of the Company. During the term of your employment hereunder, you shall devote your best efforts and your full business time, skill and attention to the performance of your duties on behalf of the Company.

3. Compensation.

(a) For all services rendered and to be rendered hereunder, and for the other agreements by you contained herein, the Company agrees to pay you, and you agree to accept a salary of $16,666.67 per month. Such salary will be subject to review and adjustment on an annual basis in accordance with the procedures set forth by the Company’s Board of Directors or Compensation Committee of the Board of Directors. Any such salary shall be payable pursuant to the Company’s payroll procedures which may be changed by the Company from time to time

and shall be subject to such deductions or withholdings as the Company is required to make pursuant to law, or by further agreement with you. In addition to your base salary, you may be eligible to receive a bonus pursuant to an employee bonus plan as approved by the Board of Directors in its sole discretion. You will also be eligible to participate in the Company’s benefit plans based on the eligibility criteria for each of those plans as they become available, which plans will remain subject to change from time to time at the Company’s discretion.

(c) Termination for Cause. In the event you are terminated by the Company for Cause (as defined below), the Company’s obligation to make payments hereunder shall cease upon the date of receipt by you of written notice and explanation of such termination (the “ Date of Termination ”), and you shall not be entitled to any severance pay, accelerated vesting, pay in lieu of notice or any other such compensation, except the Company shall pay you (i) any salary earned but unpaid prior to the Date of Termination and all accrued but unused vacation, (ii) if applicable, all commissions rightfully earned prior to the Date of Termination and (iii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the Date of Termination. Vesting of any stock options outstanding on the Date of Termination shall cease on the Date of Termination.

(d) Termination by the Company Without Cause or Resignation for Good Reason. Subject to the terms and conditions of this Agreement, the Company will provide you

with Severance Benefits (as defined below) if (i) the Company terminates your employment without Cause or (ii) you resign your employment for Good Reason. You will not be entitled to receive any Severance Benefits if (A) the Company terminates your employment for Cause, (B) you resign from your employment with the Company other than for Good Reason, or (C) in the event of your death or permanent disability, or (D) your employment is terminated because of the Company’s insolvency prior to the closing of a preferred stock financing of the Company resulting in gross proceeds to the Company of at least $3,000,000. In addition, to the extent that any federal, state or local laws, including, without limitation, so-called “plant closing” laws, require the Company to give advance notice or make a payment of any kind to you because of your involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change of control, or any other similar event or reason, the Severance Benefits payable under this Agreement shall either be reduced proportionately or eliminated, such that the total amounts paid to you do not exceed the amounts specified herein. The Severance Benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of your involuntary termination of employment for the foregoing reasons.

5. Description of Severance Benefits. For purposes of this Agreement, “ Severance Benefits ” are defined as:

(a) severance pay (the “ Severance Pay ”) equivalent to: (A)(i) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of full-time employment with the Company if a Notice Date (as defined below) occurs (a) on the same day as a Corporate Transaction or (b) within thirteen (13) months after the effective date of a Corporate Transaction or (ii) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of full-time employment with the Company if a Corporate Transaction has not occurred on or before the Notice Date; and (B) a pro rata portion of any bonus compensation under any employee bonus plan that has been approved by the Board of Directors (“ Bonus Pay ”) payable to you for the fiscal year in which your employment terminated to be paid at the same time that such incentive bonus would have been paid if such termination had not occurred. Your pro rata portion of any Bonus Pay shall be based upon the number of days in such calendar year elapsed through the Notice Date of such termination as a proportion of 365.

The date you are notified that your employment with the Company is being terminated without Cause or the date you notify the Company that you are terminating your employment for Good Reason, shall be referred to herein as the “ Notice Date .” The Severance Pay shall be payable in equal installments over the applicable number of months (the “ Initial Severance Period ”) in accordance with the Company’s then applicable payroll policies, beginning no earlier than seven (7) days after the effective date of the release described below, and will be subject to standard payroll deductions and withholdings; provided , however , that any Bonus Pay shall not be payable to you until such time as bonus compensation under the applicable employee bonus plan is paid to other employees of the Company; and

month in which your Notice Date occurs, payable at the sole discretion of the Company either in advance on the first day of each month or in a single lump sum, whether or not you elect or are eligible to receive COBRA; provided , that even if you do not elect or are not eligible to receive COBRA, you shall receive the equivalent of such out-of-pocket costs paid by you not to exceed the costs that such benefits would equal under COBRA if you were so eligible.

6. Parachute Payments.

(a) Notwithstanding anything in this Agreement to the contrary, if any payment or benefit you would receive pursuant to a Corporate Transaction from the Company or otherwise (“ Payment ”) (i) would constitute a “parachute payment” within the meaning of Section 280G of the Internal Revenue Code of 1986, as amended (the “ Code ”), and (ii) but for this sentence, would be subject to the excise tax imposed by Section 4999 of the Code (the “ Excise Tax ”), then such Payment shall be equal to the Reduced Amount (as defined below). For the avoidance of doubt, a Payment shall not be considered a parachute payment for purposes of this paragraph if such Payment is approved by the shareholders of the Company in accordance with the procedures set forth in Sections 280G(b)(5)(A)(ii) and (B) of the Code and the regulations thereunder, and at the time of such shareholder approval, no stock of the Company is readily tradeable on an established securities market or otherwise (within the meaning of Section 280G(b)(5)(A)(ii)(I) of the Code) (“ 280G Shareholder Approval ”). The “ Reduced Amount ” shall be either (i) the largest portion of the Payment that would result in no portion of the Payment being subject to the Excise Tax, or (ii) the Payment or a portion thereof after payment of the applicable Excise Tax, whichever amount after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax basis, of the greatest amount of the Payment to you. If a reduction in payments or benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, reduction shall occur in the following order unless you elect in writing a different order ( provided, however, that such

election shall be subject to Company approval if made on or after the date on which the event that triggers the Payment occurs): reduction of cash payments; cancellation of accelerated vesting of stock awards; reduction of employee benefits. In the event that acceleration of vesting of stock award compensation is to be reduced, such acceleration of vesting shall be cancelled in the reverse order of the date of grant of your stock awards unless you elect in writing a different order for cancellation.

(b) The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the event giving rise to the Payment (“ Payment Event ”) shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the Payment Event, the Board shall have the discretion to appoint a nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder.

8. Description of Corporate Transaction. For purposes of this Agreement, “ Corporate Transaction ” is defined as: (i) a sale of all or substantially all of the assets of the Company; (ii) a merger, consolidation or reorganization involving the Company if, immediately after the consummation of such merger, consolidation or reorganization, the stockholders of the Company immediately prior thereto do not own, directly or indirectly, either (A) outstanding voting securities representing more than fifty percent (50%) of the combined outstanding voting power of the surviving entity in such merger, consolidation or reorganization or (B) more than fifty percent (50%) of the combined outstanding voting power of the parent of the surviving entity in such merger, consolidation or similar transaction; or (iii) any transaction (including without limitation a merger or reorganization in which the Company is the surviving entity) which results in any person or entity (other than persons who are stockholders or affiliates of the Company immediately prior to the transaction) owning fifty percent (50%) or more of the combined voting power of all classes of stock of the Company, other than the sale by the Company of stock in transactions the primary purpose of which is to raise capital for the Company’s operations and activities.

9. Salary and Accrued PTO/Vacation. On your last date of employment with the Company, the Company will pay to you all of your accrued salary and all of your accrued but unused paid time off (“ PTO ”) or vacation as the case may be earned through your last day of employment.

10. Definition of Base Salary. For purposes of this Agreement, “ Base Salary ” means your base salary in effect as of your last day of full-time employment with the Company, excluding the following: any type of commissions, incentive payments or any other similar remuneration paid directly to you, or any other income received in connection with stock options, contributions made by the Company under any employee benefit plan, or similar items of compensation.

11. Definition of Cause. For purposes of this Agreement, “ Cause ” means that you have committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of this Agreement or of your Employee Intellectual Property, Confidentiality and Non-Compete Agreement (a copy of which is attached hereto as Exhibit B ) (the “ Employee Intellectual Property Agreement ”) or any other contract between you and the Company. In the event you are terminated for Cause you will not be entitled to the Severance Benefits, pay in lieu of notice, vesting of any shares under any option plan, vesting of any unrestricted shares, or any other such compensation set forth herein and you shall immediately forfeit all rights to any options to purchase shares of the Company’s common stock (including vested options) and such options shall immediately expire, but you will be entitled to all other compensation (including commissions rightfully earned), benefits and unreimbursed expenses accrued through the Date of Termination.

more than fifteen percent (15%), other than any such decrease resulting from a general reduction by the Company in the base salary of all Company executive officers; or (iii) the Company unilaterally makes significant detrimental reductions in your job responsibilities; provided, that you shall give written notice to the Chairman of the Company’s Board of Directors setting forth your intent to resign for Good Reason and the facts in support of your claim that Good Reason exists within ninety (90) days of the initial existence of any of the foregoing conditions; and the Company shall have thirty (30) days after the applicable party has received such notice to take such actions, if any, as the Company may deem appropriate to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred); and your final separation from service occurs within two (2) years of the initial existence of any of the foregoing conditions. If the Company acts to eliminate such claimed Good Reason within the thirty (30) day period after receipt of your notice, then you shall not be deemed to be resigning for Good Reason under such facts.

14. Employee Intellectual Property Agreement.

(a) Execution and Compliance . You acknowledge that you are a member of the Company’s executive and management personnel and that, as such, you have been and will be privy to extremely sensitive, confidential and valuable commercial information, which constitutes trade secrets of the Company, the disclosure of which would greatly harm the Company. Your work for the Company is conditioned on your execution of and continued compliance with the Employee Intellectual Property Agreement, which shall continue in full force and effect.

15. Miscellaneous. Except as specifically set forth herein, this Agreement constitutes the complete, final and exclusive embodiment of the entire agreement between you and the Company with regard to your employment terms and Severance Benefits. It is entered into without reliance on any promise or representation, written or oral, other than those expressly contained herein, and it supersedes any other such promises, warranties or representations. This Agreement may not be modified or amended except in writing signed by you and a duly authorized officer of the Company. This Agreement will be deemed to have been entered into and will be construed and enforced in accordance with the laws of the State of Colorado as applied to contracts made and to be performed entirely within Colorado.

*****

Please sign below to indicate your understanding and acceptance of this Agreement and return the signed original to me at your earliest convenience.


Very truly yours,

ARCA BIOPHARMA , I NC .

By:	/s/ Richard B. Brewer
Name:	Richard B. Brewer
Title:	President and CEO

U NDERSTOOD AND A GREED :

/s/ Christopher D. Ozeroff		June 12, 2008
Christopher D. Ozeroff		Date

E XHIBIT A

RELEASE

I also hereby acknowledge that I am knowingly and voluntarily waiving and releasing any rights I may have under the federal Age Discrimination in Employment Act of 1967, as amended (“ ADEA ”). I also acknowledge that the consideration given for the release in the preceding paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that:

(a)

my waiver and release do not apply to any rights or claims that arise on or after the date I execute this release;

(b)

I have the right to consult with an attorney prior to executing this release;

(c)

I have twenty-one (21) days to consider this release (although I may choose to voluntarily execute this release earlier);

(d)

I have seven (7) days following my execution of this release to revoke the release; and

(e)

this release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I execute this release.

I accept and agree to the terms and conditions stated above.



Christopher D. Ozeroff

Date:

ARCA BIOPHARMA , I NC .

By:
Name:
Title:

E XHIBIT B

EMPLOYEE INTELLECTUAL PROPERTY, CONFIDENTIALITY AND

NON-COMPETE AGREEMENT

[Omitted]

Exhibit 10.46

ASSIGNMENT AND ASSUMPTION AGREEMENT

THIS ASSIGNMENT AND ASSUMPTION AGREEMENT (the “ Agreement ”) is entered into as of January 26, 2009 (the “ Effective Date ”), by and between ARCA biopharma, Inc., a Delaware corporation, formerly known as Nuvelo, Inc. (“ Assignee ”), and ARCA biopharma Colorado, Inc., a Delaware corporation, formerly know as ARCA biopharma, Inc. (“ Assignor ”). Assignor and Assignee are each individually referred to herein as a “ Party ,” and collectively referred to as the “ Parties .”

RECITALS

WHEREAS, Assignor desires to assign to Assignee, and Assignee desires to assume, all Assignor’s rights and obligations under that certain Amended and Restated Employment and Retention Agreement (the “ Employment Agreement ”) dated as of June 4, 2008, by and between Assignor and Dr. Michael R. Bristow.

NOW THEREFORE, for good and valuable consideration, the sufficiency of which is hereby acknowledged, the Parties agree as follows:

1. Assignment and Assumption .

1.1 Assignor hereby assigns, transfers and sets over to Assignee, and Assignee hereby assumes, all Assignor’s right, title, interest, powers, privileges, remedies, duties, liabilities and obligations under the Employment Agreement. As of the Effective Date, Assignee shall become entitled to all such right, title, interest, powers, privileges and remedies of Assignor and subject to all such duties, liabilities and obligations of Assignor, in each case as if Assignee were the original party to the Employment Agreement.

1.2 As of the Effective Date, the term “Company,” as used in the Employment Agreement, shall refer to Assignee, and Assignee will be bound by and perform Assignor’s obligations under the Employment Agreement.

2. Miscellaneous .

2.1 This Agreement shall be governed by and construed and interpreted in accordance with the substantive laws of the State of Colorado, without regard to conflicts of law provisions.

2.2. This Agreement constitutes the entire agreement among the Parties with respect to the subject matter hereof. This Agreement shall not be altered, amended, modified or otherwise changed by any oral communications of any kind or character, or by any written communication, unless signed by a duly authorized representative of each of the Parties.

[Signature Page Follows]

IN WITNESS WHEREOF , the Parties have caused this Agreement to be duly executed as of the date first written above.


ARCA BIOPHARMA, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ARCA BIOPHARMA COLORADO, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ACKNOWLEDGED AND AGREED:

/s/ Dr. Michael R. Bristow

Dr. Michael R. Bristow

Exhibit 10.47

ASSIGNMENT AND ASSUMPTION AGREEMENT

RECITALS

WHEREAS, Assignor desires to assign to Assignee, and Assignee desires to assume, all Assignor’s rights and obligations under that certain Amended and Restated Employment and Retention Agreement (the “ Employment Agreement ”) dated as of July 7, 2008, by and between Assignor and Richard Brewer.

NOW THEREFORE, for good and valuable consideration, the sufficiency of which is hereby acknowledged, the Parties agree as follows:

1. Assignment and Assumption .

2. Miscellaneous .

2.1 This Agreement shall be governed by and construed and interpreted in accordance with the substantive laws of the State of Colorado, without regard to conflicts of law provisions.

[Signature Page Follows]

IN WITNESS WHEREOF , the Parties have caused this Agreement to be duly executed as of the date first written above.


ARCA BIOPHARMA, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ARCA BIOPHARMA COLORADO, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ACKNOWLEDGED AND AGREED:

/s/ Richard Brewer

Richard Brewer

Exhibit 10.48

ASSIGNMENT AND ASSUMPTION AGREEMENT

RECITALS

WHEREAS, Assignor desires to assign to Assignee, and Assignee desires to assume, all Assignor’s rights and obligations under that certain Amended and Restated Employment and Retention Agreement (the “ Employment Agreement ”) dated as of June 12, 2008, by and between Assignor and Christopher D. Ozeroff.

NOW THEREFORE, for good and valuable consideration, the sufficiency of which is hereby acknowledged, the Parties agree as follows:

1. Assignment and Assumption .

2. Miscellaneous .

2.1 This Agreement shall be governed by and construed and interpreted in accordance with the substantive laws of the State of Colorado, without regard to conflicts of law provisions.

[Signature Page Follows]

IN WITNESS WHEREOF , the Parties have caused this Agreement to be duly executed as of the date first written above.


ARCA BIOPHARMA, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ARCA BIOPHARMA COLORADO, INC.

By:		/s/ Christopher D. Ozeroff
Name:		Christopher D. Ozeroff
Title:		Executive Vice President of Business Development and General Counsel

ACKNOWLEDGED AND AGREED:

/s/ Christopher D. Ozeroff

Christopher D. Ozeroff

Exhibit 10.50

LOGO

February 11, 2009

Randall St. Laurent

101 Vagabond Way

Alamo, CA 94507

Re:	Employment Agreement

Dear Randy:

ARCA biopharma, Inc. (the “ Company ”) is pleased to offer you the following agreement regarding your employment as the Company’s Executive Vice President of Commercial Operations and certain severance benefits (the “ Agreement ”). This Agreement amends, supersedes and terminates any and all prior agreements or understandings with respect to your employment terms and severance benefits; provided , however , that, except as otherwise expressly provided, the Employee Intellectual Property Agreement (as defined below) is not modified or terminated hereby, and shall continue in full force and effect.

2. Duties. You shall render exclusive, full-time services to the Company as its Executive Vice President of Commercial Operations and shall report to the Company’s President and Chief Executive Officer. Your responsibilities, title, working conditions, duties, reporting relationship and/or any other aspect of your employment may be changed, added to or eliminated during your employment at the sole discretion of the Company. During the term of your employment hereunder, you shall devote your best efforts and your full business time, skill and attention to the performance of your duties on behalf of the Company.

3. Compensation. For all services rendered and to be rendered hereunder, and for the other agreements by you contained herein, the Company agrees to pay you, and you agree to accept a salary of $ 23,691.50 per month. Such salary will be subject to review and adjustment on an annual basis in accordance with the procedures set forth by the Company’s Board of Directors or Compensation Committee of the Board of Directors. Any such salary shall be payable pursuant to the Company’s payroll procedures which may be changed by the Company from time to time and shall be subject to such deductions or withholdings as the Company is required to make pursuant to law, or by further agreement with you. In addition to your base salary, you may be eligible to receive a bonus pursuant to an employee bonus plan as approved by the Board of Directors in its sole discretion. You will also be eligible to participate in the Company’s benefit plans based on the eligibility criteria for each of those plans as they become available, which plans will remain subject to change from time to time at the Company’s discretion.

(c) Termination for Cause. In the event you are terminated by the Company for Cause (as defined below), the Company’s obligation to make payments hereunder shall cease upon the date of receipt by you of written notice and explanation of such termination (the “ Date of Termination ”), and you shall not be entitled to any severance pay, accelerated vesting, pay in lieu of notice or any other such compensation, except the Company shall pay you (i) any salary earned but unpaid prior to the Date of Termination and all accrued but unused vacation, (ii) if applicable, all commissions rightfully earned prior to the Date of Termination and (iii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the Date of Termination. Vesting of any stock options outstanding on the Date of Termination shall cease on the Date of Termination.

the event of your death or permanent disability. In addition, to the extent that any federal, state or local laws, including, without limitation, so-called “plant closing” laws, require the Company to give advance notice or make a payment of any kind to you because of your involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change of control, or any other similar event or reason, the Severance Benefits payable under this Agreement shall either be reduced proportionately or eliminated, such that the total amounts paid to you do not exceed the amounts specified herein. The Severance Benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of your involuntary termination of employment for the foregoing reasons.

5. Description of Severance Benefits. For purposes of this Agreement, “ Severance Benefits ” are defined as:

(a) severance pay (the “ Severance Pay ”) equivalent to: (A)(i) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of employment with the Company in accordance with this agreement if a Notice Date (as defined below) occurs (a) on the same day as a Corporate Transaction or (b) within thirteen (13) months after the effective date of a Corporate Transaction or (ii) six (6) months of your Base Salary (as defined below) in effect as of your last day of full-time employment with the Company if a Corporate Transaction has not occurred on or within thirteen (13) months before the Notice Date; and (B) a pro rata portion of any bonus compensation under any employee bonus plan that has been approved by the Board of Directors (“ Bonus Pay ”) payable to you for the fiscal year in which your employment terminated to be paid at the same time that such incentive bonus would have been paid if such termination had not occurred. Your pro rata portion of any Bonus Pay shall be based upon the number of days in such calendar year elapsed through the Notice Date of such termination as a proportion of 365.

The date you are notified that your employment with the Company is being terminated without Cause or the date you notify the Company that you are terminating your employment for Good Reason, shall be referred to herein as the “ Notice Date .” The Severance Pay shall be payable in equal installments over the applicable number of months (the “ Initial Severance Period ”) in accordance with the Company’s then applicable payroll policies, beginning no earlier than seven (7) days after the effective date of the release described below, and will be subject to standard payroll deductions and withholdings; provided , however , that any Bonus Pay shall not be payable to you until such time as bonus compensation under the applicable employee bonus plan is paid to other employees of the Company; and

(b) reimbursement of your out-of-pocket costs to continue your group health insurance benefits (and dependent coverage, if applicable) under COBRA at substantially the same level of coverage in effect immediately prior to the Notice Date for (i) twelve (12) months, if Severance Pay is payable pursuant to paragraph 5(a)(A)(i) above, or (ii) six (6) months, if Severance Pay is payable pursuant to paragraph 5(a)(A)(ii) above, following the last day of the month in which your Notice Date occurs, payable at the sole discretion of the Company either in advance on the first day of each month or in a single lump sum, whether or not you elect or are eligible to receive COBRA; provided , that even if you do not elect or are not eligible to receive COBRA, you shall receive the equivalent of such out-of-pocket costs paid by you not to exceed the costs that such benefits would equal under COBRA if you were so eligible.

(c) The Company may elect, in its sole discretion, to pay you the equivalent of up to twelve (12) months of your Base Salary in effect as of your last day of employment with the Company in accordance with this agreement , which additional payment shall extend your covenants and obligations set forth in Article IV of the Employee Intellectual Property, Confidentiality and Non-Compete Agreement for such additional period. If the Company elects to make such additional payment to you, the Company shall make such payments in equal installments over the applicable number of months following the Initial Severance Period in accordance with the Company’s then applicable payroll policies, or in the sole discretion of the Company as designated by the Company in writing within seven (7) days after the Notice Date, in a single lump sum cash payment, subject to standard payroll deductions and withholdings, and such additional amounts shall be deemed to be “Severance Pay” and to be part of the “Severance Benefits” for purposes of this Agreement.

6. Parachute Payments.

(a) Notwithstanding anything in this Agreement to the contrary, if any payment or benefit you would receive pursuant to a Corporate Transaction from the Company or otherwise (“ Payment ”) (i) would constitute a “parachute payment” within the meaning of Section 280G of the Internal Revenue Code of 1986, as amended (the “ Code ”), and (ii) but for this sentence, would be subject to the excise tax imposed by Section 4999 of the Code (the “ Excise Tax ”), then such Payment shall be equal to the Reduced Amount (as defined below). For the avoidance of doubt, a Payment shall not be considered a parachute payment for purposes of this paragraph if such Payment is approved by the shareholders of the Company in accordance with the procedures set forth in Sections 280G(b)(5)(A)(ii) and (B) of the Code and the regulations thereunder, and at the time of such shareholder approval, no stock of the Company is readily tradeable on an established securities market or otherwise (within the meaning of Section 280G(b)(5)(A)(ii)(I) of the Code) (“ 280G Shareholder Approval ”). The “ Reduced Amount ” shall be either (i) the largest portion of the Payment that would result in no portion of the Payment being subject to the Excise Tax, or (ii) the Payment or a portion thereof after payment of the applicable Excise Tax, whichever amount after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax basis, of the greatest amount of the Payment to you. If a reduction in payments or benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, reduction shall occur in the following order unless you elect in writing a different order ( provided, however, that such election shall be subject to Company approval if made on or after the date on which the event that triggers the Payment occurs): reduction of cash payments; cancellation of accelerated vesting of stock awards; reduction of employee benefits. In the event that acceleration of vesting of stock award compensation is to be reduced, such acceleration of vesting shall be cancelled in the reverse order of the date of grant of your stock awards unless you elect in writing a different order for cancellation.

(b) The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the event giving rise to the Payment (“ Payment Event ”) shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the Payment Event, the Board shall have the discretion to appoint a nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder.

fifty percent (50%) of the combined outstanding voting power of the parent of the surviving entity in such merger, consolidation or similar transaction; or (iii) any transaction (including without limitation a merger or reorganization in which the Company is the surviving entity) which results in any person or entity (other than persons who are stockholders or affiliates of the Company immediately prior to the transaction) owning fifty percent (50%) or more of the combined voting power of all classes of stock of the Company, other than the sale by the Company of stock in transactions the primary purpose of which is to raise capital for the Company’s operations and activities.

9. Salary and Accrued PTO/Vacation. On your last date of employment with the Company, the Company will pay to you all of your accrued salary and all of your accrued but unused paid time off (“ PTO ”) or vacation as the case may be earned through your last day of employment.

10. Definition of Base Salary. For purposes of this Agreement, “ Base Salary ” means your base salary in effect as of your last day of full-time employment with the Company, excluding the following: any type of commissions, incentive payments or any other similar remuneration paid directly to you, or any other income received in connection with stock options, contributions made by the Company under any employee benefit plan, or similar items of compensation.

11. Definition of Cause. For purposes of this Agreement, “ Cause ” means that you have committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of this Agreement or of your Employee Intellectual Property, Confidentiality and Non-Compete Agreement (a copy of which is attached hereto as Exhibit B ) (the “ Employee Intellectual Property Agreement ”) or any other contract between you and the Company. In the event you are terminated for Cause you will not be entitled to the Severance Benefits, pay in lieu of notice, vesting of any shares under any option plan, vesting of any unrestricted shares, or any other such compensation set forth herein and you shall immediately forfeit all rights to any options to purchase shares of the Company’s common stock (including vested options) and such options shall immediately expire, but you will be entitled to all other compensation (including commissions rightfully earned), benefits and unreimbursed expenses accrued through the Date of Termination.

12. Definition of Good Reason. For purposes of this Agreement, “ Good Reason ” shall mean (i) the relocation of your normal principal place of work greater than thirty (30) miles from your then current normal work location; (ii) a decrease in your then current base salary of more than fifteen percent (15%), other than any such decrease resulting from a general reduction by the Company in the base salary of all Company executive officers; or (iii) the Company unilaterally makes significant detrimental reductions in your job responsibilities; provided, that you shall give written notice to the Chairman of the Company’s Board of Directors setting forth your intent to resign for Good Reason and the facts in support of your claim that Good Reason exists within ninety (90) days of the initial existence of any of the foregoing conditions; and the Company shall have thirty (30) days after the applicable party has received such notice to take

such actions, if any, as the Company may deem appropriate to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred); and your final separation from service occurs within two (2) years of the initial existence of any of the foregoing conditions. If the Company acts to eliminate such claimed Good Reason within the thirty (30) day period after receipt of your notice, then you shall not be deemed to be resigning for Good Reason under such facts.

14. Employee Intellectual Property Agreement.

*****

Please sign below to indicate your understanding and acceptance of this Agreement and return the signed original to me at your earliest convenience.


Very truly yours,

ARCA B IOPHARMA , I NC .

By:	/s/ Richard B. Brewer
Name:	Richard B. Brewer
Title:	President and CEO

U NDERSTOOD AND A GREED :

/s/ Randall St. Laurent		February 24, 2009
Randall St. Laurent		Date

E XHIBIT A

RELEASE

I also hereby acknowledge that I am knowingly and voluntarily waiving and releasing any rights I may have under the federal Age Discrimination in Employment Act of 1967, as amended (“ ADEA ”). I also acknowledge that the consideration given for the release in the preceding paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that:

(a)

my waiver and release do not apply to any rights or claims that arise on or after the date I execute this release;

(b)

I have the right to consult with an attorney prior to executing this release;

(c)

I have twenty-one (21) days to consider this release (although I may choose to voluntarily execute this release earlier);

(d)

I have seven (7) days following my execution of this release to revoke the release; and

(e)

this release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I execute this release.

I accept and agree to the terms and conditions stated above.



Randall St. Laurent

Date:

ARCA BIOPHARMA , I NC .

By:
Name:
Title:

E XHIBIT B

EMPLOYEE INTELLECTUAL PROPERTY, CONFIDENTIALITY AND NON-COMPETE AGREEMENT

[Omitted]

Exhibit 10.51

LOGO

February 23, 2009

Kathryn E. Falberg

52 Piedmont Road

Larkspur, CA 94939

Re:	Employment Agreement

Dear Kate:

ARCA biopharma, Inc. (the “ Company ”) is pleased to offer you the following agreement regarding your employment as the Company’s Chief Financial Officer and Chief Operating Officer and certain severance benefits (the “ Agreement ”). This Agreement amends, supersedes and terminates any and all prior agreements or understandings with respect to your employment terms and severance benefits, including but not limited to, that certain Offer Letter dated February 18, 2009; provided , however , that, except as otherwise expressly provided, the Employee Intellectual Property Agreement (as defined below) is not modified or terminated hereby, and shall continue in full force and effect.

2. Duties. You shall render exclusive, full-time services to the Company as its Chief Financial Officer and Chief Operating Officer and shall report to the Company’s President and Chief Executive Officer. Your responsibilities, title, working conditions, duties, reporting relationship and/or any other aspect of your employment may be changed, added to or eliminated during your employment at the sole discretion of the Company. During the term of your employment hereunder, you shall devote your best efforts and your full business time, skill and attention to the performance of your duties on behalf of the Company.

3. Compensation.

(a) For all services rendered and to be rendered hereunder, and for the other agreements by you contained herein, the Company agrees to pay you, and you agree to accept a salary of $25,000.00 per month. Such salary will be subject to review and adjustment on an annual basis in accordance with the procedures set forth by the Company’s Board of Directors or Compensation Committee of the Board of Directors. Any such salary shall be payable pursuant to the Company’s payroll procedures which may be changed by the Company from time to time and shall be subject to such deductions or withholdings as the Company is required to make

pursuant to law, or by further agreement with you. In addition to your base salary, you may be eligible to receive a bonus pursuant to an employee bonus plan as approved by the Board of Directors in its sole discretion. Your target bonus percentage will be forty percent (40%) of your base salary and any bonus earned shall be paid at the same time as bonuses are paid to your peer executives at the Company. You will also be eligible to participate in the Company’s benefit plans based on the eligibility criteria for each of those plans as they become available, which plans will remain subject to change from time to time at the Company’s discretion.

(b) You will be granted an option (the “ Initial Option ”) to purchase 49,500 shares of the Company’s Common Stock, within thirty (30) days following the Start Date, with an exercise price equal to the market value of the Company’s stock on the date of grant. The terms and conditions of Initial Option will be governed by your Stock Option Agreement with the Company, which you will sign, and the Company’s 2004 Equity Incentive Plan.

earned but unpaid prior to the Date of Termination and all accrued but unused vacation, (ii) if applicable, all commissions rightfully earned prior to the Date of Termination and (iii) any business expenses incurred by you in connection with your performance of your duties, according to the policies of the Company, that were incurred but not reimbursed as of the Date of Termination. Vesting of any stock options outstanding on the Date of Termination shall cease on the Date of Termination.

(d) Termination by the Company Without Cause or Resignation for Good Reason. Subject to the terms and conditions of this Agreement, the Company will provide you with Severance Benefits (as defined below) if (i) the Company terminates your employment without Cause or (ii) you resign your employment for Good Reason. You will not be entitled to receive any Severance Benefits if (A) the Company terminates your employment for Cause, (B) you resign from your employment with the Company other than for Good Reason, or (C) in the event of your death or permanent disability. In addition, to the extent that any federal, state or local laws, including, without limitation, so-called “plant closing” laws, require the Company to give advance notice or make a payment of any kind to you because of your involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change of control, or any other similar event or reason, the Severance Benefits payable under this Agreement shall either be reduced proportionately or eliminated, such that the total amounts paid to you do not exceed the amounts specified herein. The Severance Benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of your involuntary termination of employment for the foregoing reasons.

5. Description of Severance Benefits. For purposes of this Agreement, “ Severance Benefits ” are defined as:

(a) (i) severance pay (the “ Severance Pay ”) equivalent to: (A)(i) twelve (12) months of your Base Salary (as defined below) in effect as of your last day of employment with the Company in accordance with this agreement (which payment will not extend your covenants and obligations set forth in Article IV of the Employee Intellectual Property, Confidentiality and Non-Compete Agreement) ; and (B) a pro rata portion of any bonus compensation under any employee bonus plan that has been approved by the Board of Directors (“ Bonus Pay ”) payable to you for the fiscal year in which your employment terminated to be paid at the same time that such incentive bonus would have been paid if such termination had not occurred; and (ii) acceleration of the vesting of fifty percent (50%) of the unvested portion of the Initial Option. Your pro rata portion of any Bonus Pay shall be based upon the number of days in such calendar year elapsed through the Notice Date of such termination as a proportion of 365. (For the purpose of clarification, the Bonus Pay is in addition to any bonus you have earned for the prior fiscal year under any employee bonus plan approved by the Board of Directors, which bonus shall be payable as provided in Section 3(a), regardless of whether the Notice Date occurs prior to the determination of the bonus for the prior fiscal year) .

Pay shall be payable in equal installments over twelve months (the “ Initial Severance Period ”) in accordance with the Company’s then applicable payroll policies, beginning no earlier than seven (7) days after the effective date of the release described below, and will be subject to standard payroll deductions and withholdings; provided , however , that any Bonus Pay shall not be payable to you until such time as bonus compensation under the applicable employee bonus plan is paid to other employees of the Company; and

(b) reimbursement of your out-of-pocket costs to continue your group health insurance benefits (and dependent coverage, if applicable) under COBRA at substantially the same level of coverage in effect immediately prior to the Notice Date for twelve (12) months, following the last day of the month in which your Notice Date occurs, payable in advance on the first day of each month whether or not you elect or are eligible to receive COBRA; provided , that even if you do not elect or are not eligible to receive COBRA, you shall receive the equivalent of such out-of-pocket costs paid by you not to exceed the costs that such benefits would equal under COBRA if you were so eligible.

To receive any of the Severance Benefits, you must first sign and date and must not revoke a general release of claims in favor of the Company in the form attached hereto as Exhibit A (the “ Release ”). Such Release shall not be signed or dated until the Notice Date, and, except as otherwise required by applicable law, is not valid (and will not entitle you to Severance Benefits) unless signed and delivered to the Company within three (3) days after such Notice Date.

(c) The Company may elect, in its sole discretion, to pay you up to twelve (12) months of your Base Salary in effect as of your last day of employment with the Company in accordance with this agreement , which additional payment shall extend your covenants and obligations set forth in Article IV of the Employee Intellectual Property, Confidentiality and Non-Compete Agreement for an additional period equal to the number of months of your Base Salary that the Company elects to pay your under this sub-paragraph. If the Company elects to make such additional payment to you, the Company shall make such payments in equal installments over the applicable number of months following the Initial Severance Period, if any, in accordance with the Company’s then applicable payroll policies, or in the sole discretion of the Company as designated by the Company in writing within seven (7) days after the Notice Date, in a single lump sum cash payment, subject to standard payroll deductions and withholdings, and such additional amounts shall be deemed to be “Severance Pay” and to be part of the “Severance Benefits” for purposes of this Agreement.

6. Parachute Payments.

For the avoidance of doubt, a Payment shall not be considered a parachute payment for purposes of this paragraph if such Payment is approved by the shareholders of the Company in accordance with the procedures set forth in Sections 280G(b)(5)(A)(ii) and (B) of the Code and the regulations thereunder, and at the time of such shareholder approval, no stock of the Company is readily tradeable on an established securities market or otherwise (within the meaning of Section 280G(b)(5)(A)(ii)(I) of the Code) (“ 280G Shareholder Approval ”). The “ Reduced Amount ” shall be either (i) the largest portion of the Payment that would result in no portion of the Payment being subject to the Excise Tax, or (ii) the Payment or a portion thereof after payment of the applicable Excise Tax, whichever amount after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in your receipt, on an after-tax basis, of the greatest amount of the Payment to you. If a reduction in payments or benefits constituting “parachute payments” is necessary so that the Payment equals the Reduced Amount, reduction shall occur in the following order: reduction of cash payments; cancellation of accelerated vesting of stock awards; reduction of employee benefits. In the event that acceleration of vesting of stock award compensation is to be reduced, such acceleration of vesting shall be cancelled in the reverse order of the date of grant of your stock awards unless you elect in writing a different order for cancellation. You may elect to decline the acceleration of vesting of stock awards so as to avoid having any other right, payment or benefit deemed to be a parachute payment; provided , however , that in order to comply with Section 409A of the Code, in the event you make such an election, the reduction or elimination of the acceleration of vesting will only be permitted if the same result would be obtained by reducing the dollar value of all rights, payments or benefits in the order in which each dollar of value subject to a right, payment or award reduces the parachute payment to the greatest extent.

(b) The accounting firm engaged by the Company for general audit purposes as of the day prior to the effective date of the event giving rise to the Payment (“ Payment Event ”) shall perform the foregoing calculations. If the accounting firm so engaged by the Company is serving as accountant or auditor for the individual, entity or group effecting the Payment Event, the Board shall have the discretion to appoint a nationally recognized accounting firm to make the determinations required hereunder. The Company shall bear all expenses with respect to the determinations by such accounting firm required to be made hereunder.

7. Compliance with Revenue Code Section 409A. (a) To the extent any Severance Benefits are paid from the date of termination of your employment through March 15 of the

calendar year following such termination, such Severance Benefits are intended to constitute separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations and thus payable pursuant to the “short-term deferral” rule set forth in Section 1.409A-1(b)(4) of the Treasury Regulations; (b) are paid following said March 15, such Severance Benefits are intended to constitute separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations made upon an involuntary separation from service and payable pursuant to Section 1.409A-1(b)(9)(iii) of the Treasury Regulations, to the maximum extent permitted by said provision, and (c) are in excess of the amounts specified in clauses (a) and (b) of this paragraph, shall (unless otherwise exempt under Treasury Regulations) be considered separate payments subject to the distribution requirements of Section 409A(a)(2)(A) of the Code, including, without limitation, the requirement of Section 409A(a)(2)(B)(i) of the Code that payments or benefits be delayed until 6 months after your separation from service (if the Company is publicly traded and you are a “specified employee” within the meaning of the aforesaid section of the Code at the time of such separation from service). In the event that a six-month delay of any such separation payments or benefits is required, on the first regularly scheduled pay date following the conclusion of the delay period (or on your date of death, if earlier) you shall receive a lump sum payment or benefit in an amount equal to the separation payments and benefits that were so delayed, and any remaining separation payments or benefits shall be paid on the same basis and at the same time as otherwise specified pursuant to this Agreement (subject to applicable tax withholdings and deductions). For the purposes of determining when amounts otherwise payable on account of your termination of employment under this Agreement will be paid, which amounts become due because of your termination of employment, “termination of employment” or words of similar import, as used in this Agreement, shall be construed as the date that your first incur a “separation from service” for purposes of Section 409A of the Code on or following termination of employment.

(b) Any taxable reimbursement of business or other expenses as specified under this Agreement shall be subject to the following conditions: (1) the expenses eligible for reimbursement in one taxable year shall not affect the expenses eligible for reimbursement in any other taxable year; (2) the reimbursement of an eligible expense shall be made no later than the end of the year after the year in which such expense was incurred; and (3) the right to reimbursement shall not be subject to liquidation or exchange for another benefit.

(c) Any amounts otherwise payable on account of your termination of employment under this Agreement which (i) are conditioned in any part on a release of claims and (ii) would otherwise be paid (assuming the release is given) prior to the last day on which the release could become irrevocable assuming your latest possible execution and delivery of the release (such last day, the “ Release Deadline ”) shall be paid, if ever, only on the Release Deadline, even if your release becomes irrevocable before that date. The Company may elect to make such payment up to thirty (30) days prior to the Release Deadline, however.

Company immediately prior thereto do not own, directly or indirectly, either (A) outstanding voting securities representing more than fifty percent (50%) of the combined outstanding voting power of the surviving entity in such merger, consolidation or reorganization or (B) more than fifty percent (50%) of the combined outstanding voting power of the parent of the surviving entity in such merger, consolidation or similar transaction; or (iii) any transaction (including without limitation a merger or reorganization in which the Company is the surviving entity) which results in any person or entity (other than persons who are stockholders or affiliates of the Company immediately prior to the transaction) owning fifty percent (50%) or more of the combined voting power of all classes of stock of the Company, other than the sale by the Company of stock in transactions the primary purpose of which is to raise capital for the Company’s operations and activities.

9. Salary and Accrued PTO/Vacation. On your last date of employment with the Company, the Company will pay to you all of your accrued salary and all of your accrued but unused paid time off (“ PTO ”) or vacation as the case may be earned through your last day of employment.

10. Definition of Base Salary. For purposes of this Agreement, “ Base Salary ” means your base salary in effect as of your last day of full-time employment with the Company, excluding the following: any type of commissions, incentive payments or any other similar remuneration paid directly to you, or any other income received in connection with stock options, contributions made by the Company under any employee benefit plan, or similar items of compensation.

11. Definition of Cause. For purposes of this Agreement, “ Cause ” means that you have committed or engaged in: (i) willful misconduct, gross negligence, theft, fraud, or other illegal or dishonest conduct, any of which are considered to be materially harmful to the Company; (ii) refusal, unwillingness, failure, or inability to perform material job duties or habitual absenteeism; or (iii) violation of fiduciary duty, violation of any duty of loyalty, or material breach of any material term of this Agreement or of your Employee Intellectual Property, Confidentiality and Non-Compete Agreement (a copy of which is attached hereto as Exhibit B ) (the “ Employee Intellectual Property Agreement ”) or any other contract between you and the Company. In the event you are terminated for Cause you will not be entitled to the Severance Benefits, pay in lieu of notice, vesting of any shares under any option plan, vesting of any unrestricted shares, or any other such compensation set forth herein and you shall immediately forfeit all rights to any options to purchase shares of the Company’s common stock (including vested options) and such options shall immediately expire, but you will be entitled to all other compensation (including commissions rightfully earned), benefits and unreimbursed expenses accrued through the Date of Termination.

12. Definition of Good Reason. For purposes of this Agreement, “ Good Reason ” shall mean (i) the relocation of your normal principal place of work greater than fifty (50) miles from your then current normal work location; (ii) a decrease in your then current base salary of more than fifteen percent (15%), other than any such decrease resulting from a general reduction by the Company in the base salary of all Company executive officers; (iii) the Company

unilaterally makes significant detrimental reductions in your job responsibilities (for example, if the Company changes your reporting relationships such that you are no longer reporting directly to the President and Chief Executive Officer); provided, that you shall give written notice to the Chairman of the Company’s Board of Directors setting forth your intent to resign for Good Reason and the facts in support of your claim that Good Reason exists within ninety (90) days of the initial existence of any of the foregoing conditions; and the Company shall have thirty (30) days after the applicable party has received such notice to take such actions, if any, to eliminate such claimed Good Reason (without thereby admitting that such Good Reason had occurred); and your final separation from service occurs within two (2) years of the initial existence of any of the foregoing conditions. If the Company eliminates such claimed Good Reason within the thirty (30) day period after receipt of your notice, then you shall not be deemed to be resigning for Good Reason under such facts.

14. Employee Intellectual Property Agreement.

(a) Execution and Compliance . You acknowledge that you are a member of the Company’s executive and management personnel and that, as such, you have been and will be privy to extremely sensitive, confidential and valuable commercial information, which constitutes trade secrets of the Company, the disclosure of which would greatly harm the Company. Your work for the Company is conditioned on your execution of and compliance with the Employee Intellectual Property Agreement, attached hereto as Exhibit B.

*****

Please sign below to indicate your understanding and acceptance of this Agreement and return the signed original to me at your earliest convenience.


Very truly yours,

ARCA BIOPHARMA , I NC .

By:	/s/ Christopher D. Ozeroff
Name:	Christopher D. Ozeroff
Title:	EVP Business Development and General Counsel

U NDERSTOOD AND A GREED :

/ S / K ATHRYN E. F ALBERG		February 23, 2009
Kathryn E. Falberg		Date

E XHIBIT A

RELEASE

I also hereby acknowledge that I am knowingly and voluntarily waiving and releasing any rights I may have under the federal Age Discrimination in Employment Act of 1967, as amended (“ ADEA ”). I also acknowledge that the consideration given for the release in the preceding paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that:

(a)

my waiver and release do not apply to any rights or claims that arise on or after the date I execute this release;

(b)

I have the right to consult with an attorney prior to executing this release;

(c)

I have twenty-one (21) days to consider this release (although I may choose to voluntarily execute this release earlier);

(d)

I have seven (7) days following my execution of this release to revoke the release; and

(e)

this release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day after I execute this release.

I accept and agree to the terms and conditions stated above.



Kathryn E. Falberg

Date:

ARCA BIOPHARMA , I NC .

By:
Name:
Title:

E XHIBIT B

EMPLOYEE INTELLECTUAL PROPERTY, CONFIDENTIALITY AND NON-COMPETE AGREEMENT

[Omitted]

Exhibit 10.52

INDEMNITY AGREEMENT

T HIS I NDEMNITY A GREEMENT (this “Agreement”) is made and entered into this day of by and between ARCA biopharma, Inc., a Delaware corporation (the “Corporation”), and (“Agent”).

R ECITALS

W HEREAS , Agent has agreed to perform a valuable service to the Corporation as a [director/officer] of the Corporation;

W HEREAS , the Corporation has previously adopted amended and restated bylaws (as amended, the “Bylaws”) providing for the indemnification of the directors, officers, employees and other agents of the Corporation, including persons serving at the request of the Corporation in such capacities with other corporations or enterprises, as authorized by the Delaware General Corporation Law, as amended (the “Code”);

W HEREAS , the Bylaws and the Code, by their non-exclusive nature, permit contracts between the Corporation and its agents, officers, employees and other agents with respect to indemnification of such persons; and

W HEREAS , in order to induce Agent to serve as a [director/officer] of the Corporation, the Corporation has determined and agreed to enter into this Agreement with Agent;

N OW , T HEREFORE , in consideration of Agent’s service as a [director/officer] of the Corporation after the date hereof, the parties hereto agree as follows:

A GREEMENT

1. Services to the Corporation. Agent will serve, at the will of the Corporation or under separate contract, if any such contract exists, as a [director/officer] of the Corporation or as a director, officer or other fiduciary of an affiliate of the Corporation (including any employee benefit plan of the Corporation) faithfully and to the best of his ability so long as he is duly elected and qualified in accordance with the provisions of the Bylaws or other applicable charter documents of the Corporation or such affiliate; provided, however, that Agent may at any time and for any reason resign from such position (subject to any contractual obligation that Agent may have assumed apart from this Agreement) and that the Corporation or any affiliate shall have no obligation under this Agreement to continue Agent in any such position.

2. Indemnity of Agent. Subject in all instances to the terms, conditions and limitations of this Agreement, the Corporation hereby agrees to hold harmless and indemnify Agent to the fullest extent authorized or permitted by the provisions of the Bylaws and the Code, as the same may be amended from time to time (but, only to the extent that such amendment permits the Corporation to provide broader indemnification rights than the Bylaws or the Code permitted prior to adoption of such amendment).

3. Additional Indemnity. In addition to and not in limitation of the indemnification otherwise provided for herein, and subject only to the exclusions set forth in Section 4 hereof, the Corporation hereby further agrees to hold harmless and indemnify Agent:

(a) against any and all expenses (including attorneys’ fees), witness fees, damages, judgments, fines and amounts paid in settlement and any other amounts that Agent becomes legally obligated to pay because of any claim or claims made against or by him in connection with any threatened, pending or completed action, suit or proceeding, whether civil, criminal, arbitrational, administrative or investigative (including an action by or in the right of the Corporation) to which Agent is, was or at any time becomes a party, or is threatened to be made a party, by reason of the fact that Agent is, was or at any time becomes a director, officer, employee or other agent of Corporation, or is or was serving or at any time serves at the request of the Corporation as a director, officer, employee or other agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise; and

(b) otherwise to the fullest extent as may be provided to Agent by the Corporation under the non-exclusivity provisions of the Code and Section 8 of the Bylaws.

4. Limitations on Additional Indemnity. No indemnity pursuant to Section 3 hereof shall be paid by the Corporation:

(a) on account of any claim against Agent solely for an accounting of profits made from the purchase or sale by Agent of securities of the Corporation pursuant to the provisions of Section 16(b) of the Securities Exchange Act of 1934 and amendments thereto or similar provisions of any federal, state or local statutory law;

(b) on account of Agent’s conduct that is established by a final judgment as knowingly fraudulent or deliberately dishonest or that constituted willful misconduct;

(c) on account of Agent’s conduct that is established by a final judgment as constituting a breach of Agent’s duty of loyalty to the Corporation or resulting in any personal profit or advantage to which Agent was not legally entitled;

(d) [subject to Section 11(c) herein,] for which payment is actually made to Agent under a valid and collectible insurance policy or under a valid and enforceable indemnity clause, bylaw or agreement, except in respect of any excess beyond payment under such insurance, clause, bylaw or agreement (it also being understood that with respect to any policy or policies of director’s and officer’s liability insurance procured by the Corporation, in its discretion, for the benefit of its officers and directors, (i) Agent shall be named as an insured, (ii) the Company shall give prompt notice of the commencement of any proceeding involving Agent for which Agent is insured to the insurers in accordance with the procedures set forth in the respective policies, (iii) the Corporation shall thereafter take all necessary or desirable action to cause such insurers to pay, on behalf of Agent, all amounts payable as a result of such proceeding in accordance with the terms of such policies, and (iv) in the event the Corporation makes any indemnification payments to Agent and Agent is subsequently reimbursed from the proceeds of insurance, Agent shall promptly refund such indemnification payments to the Corporation to the extent of such insurance reimbursement).

(e) if indemnification is not lawful (and, in this respect, both the Corporation and Agent have been advised that the Securities and Exchange Commission believes that indemnification for liabilities arising under the federal securities laws is against public policy and is, therefore, unenforceable and that claims for indemnification should be submitted to appropriate courts for adjudication); or

(f) in connection with any proceeding (or part thereof) initiated by Agent, or any proceeding by Agent against the Corporation or its directors, officers, employees or other agents, unless (i) such indemnification is expressly required to be made by law, (ii) the proceeding was authorized by the Board of Directors of the Corporation, (iii) such indemnification is provided by the Corporation, in its sole discretion, pursuant to the powers vested in the Corporation under the Code, or (iv) the proceeding is initiated pursuant to Section 9 hereof.

5. Continuation of Indemnity. All agreements and obligations of the Corporation contained herein shall continue during the period Agent is a director, officer, employee or other agent of the Corporation (or is or was serving at the request of the Corporation as a director, officer, employee or other agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise) and shall continue thereafter so long as Agent shall be subject to any possible claim or threatened, pending or completed action, suit or proceeding, whether civil, criminal, arbitrational, administrative or investigative, by reason of the fact that Agent was serving in the capacity referred to herein.

6. Partial Indemnification. Agent shall be entitled under this Agreement to indemnification by the Corporation for a portion of the expenses (including attorneys’ fees), witness fees, damages, judgments, fines and amounts paid in settlement and any other amounts that Agent becomes legally obligated to pay in connection with any action, suit or proceeding referred to in Section 3 hereof even if not entitled hereunder to indemnification for the total amount thereof, and the Corporation shall indemnify Agent for the portion thereof to which Agent is entitled.

7. Notification and Defense of Claim. Not later than thirty (30) days after receipt by Agent of notice of the commencement of any action, suit or proceeding, Agent will, if a claim in respect thereof is to be made against the Corporation under this Agreement, notify the Corporation of the commencement thereof; but the omission so to notify the Corporation will not relieve it from any liability which it may have to Agent otherwise than under this Agreement. With respect to any such action, suit or proceeding as to which Agent notifies the Corporation of the commencement thereof:

(a) the Corporation will be entitled to participate therein at its own expense;

(b) except as otherwise provided below, the Corporation may, at its option and jointly with any other indemnifying party similarly notified and electing to assume such defense, assume the defense thereof, with counsel reasonably satisfactory to Agent. After notice from the Corporation to Agent of its election to assume the defense thereof, the Corporation will not be liable to Agent under this Agreement for any legal or other expenses subsequently incurred by Agent in connection with the defense thereof except for reasonable costs of

investigation or otherwise as provided below. Agent shall have the right to employ separate counsel in such action, suit or proceeding but the fees and expenses of such counsel incurred after notice from the Corporation of its assumption of the defense thereof shall be at the expense of Agent unless (i) the employment of counsel by Agent has been authorized by the Corporation, (ii) Agent shall have reasonably concluded, and so notified the Corporation, that there is an actual conflict of interest between the Corporation and Agent in the conduct of the defense of such action or (iii) the Corporation shall not in fact have employed counsel to assume the defense of such action, in each of which cases the fees and expenses of Agent’s separate counsel shall be at the expense of the Corporation. The Corporation shall not be entitled to assume the defense of any action, suit or proceeding brought by or on behalf of the Corporation or as to which Agent shall have made the conclusion provided for in clause (ii) above; and

(c) the Corporation shall not be liable to indemnify Agent under this Agreement for any amounts paid in settlement of any action or claim effected without its written consent, which shall not be unreasonably withheld. The Corporation shall be permitted to settle any action except that it shall not settle any action or claim in any manner which would impose any penalty or limitation on Agent without Agent’s written consent, which may be given or withheld in Agent’s sole discretion.

8. Expenses. The Corporation shall advance, prior to the final disposition of any proceeding, promptly following request therefor, all expenses incurred by Agent in connection with such proceeding upon receipt of an undertaking by or on behalf of Agent to repay said amounts if it shall be determined ultimately that Agent is not entitled to be indemnified under the provisions of this Agreement, the Bylaws, the Code or otherwise.

9. Enforcement. Any right to indemnification or advances granted by this Agreement to Agent shall be enforceable by or on behalf of Agent in any court of competent jurisdiction if (i) the claim for indemnification or advances is denied, in whole or in part, or (ii) no disposition of such claim is made within ninety (90) days of request therefor. Agent, in such enforcement action, if successful in whole or in part, shall be entitled to be paid also the expense of prosecuting his claim. It shall be a defense to any action for which a claim for indemnification is made under Section 3 hereof (other than an action brought to enforce a claim for expenses pursuant to Section 8 hereof, provided that the required undertaking has been tendered to the Corporation) that Agent is not entitled to indemnification because of the limitations set forth in Section 4 hereof. Neither the failure of the Corporation (including its Board of Directors or its stockholders) to have made a determination prior to the commencement of such enforcement action that indemnification of Agent is proper in the circumstances, nor an actual determination by the Corporation (including its Board of Directors or its stockholders) that such indemnification is improper shall be a defense to the action or create a presumption that Agent is not entitled to indemnification under this Agreement or otherwise.

10. Subrogation. [Except as provided in Section 11(c) below,] in the event of payment under this Agreement, the Corporation shall be subrogated to the extent of such payment to all of the rights of recovery of Agent [(other than against the Fund Indemnitors (as defined below))], who shall execute all documents required and shall do all acts that may be necessary to secure such rights and to enable the Corporation effectively to bring suit to enforce such rights.

11. Non-Exclusivity of Rights.

(a) The rights of indemnification as provided by this Agreement shall not be deemed exclusive of any other rights to which Agent may at any time be entitled under applicable law, the Certificate of Incorporation, the Bylaws, any agreement, a vote of stockholders, a resolution of directors or otherwise, of the Corporation. No amendment, alteration or repeal of this Agreement or of any provision hereof shall limit or restrict any right of Agent under this Agreement in respect of any action taken or omitted by such Agent in his or her capacity as an officer or director of the Corporation prior to such amendment, alteration or repeal. To the extent that a change in the Code, whether by statute or judicial decision, permits greater indemnification than would be afforded currently under the Certificate of Incorporation, Bylaws and this Agreement, it is the intent of the parties hereto that Agent shall enjoy by this Agreement the greater benefits so afforded by such change. No right or remedy herein conferred is intended to be exclusive of any other right or remedy, and every other right and remedy shall be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other right or remedy.

(b) To the extent that the Corporation maintains an insurance policy or policies providing liability insurance for directors, officers, employees, or agents or fiduciaries of the Corporation or of any other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise that such person serves at the request of the Corporation, Agent shall be covered by such policy or policies in accordance with its or their terms to the maximum extent of the coverage available for any director, officer, employee, agent or fiduciary under such policy or policies. If, at the time of the receipt of a notice of a claim pursuant to the terms hereof, the Corporation has director and officer liability insurance in effect, the Corporation shall give prompt notice of the commencement of such proceeding to the insurers in accordance with the procedures set forth in the respective policies. The Corporation shall thereafter take all necessary or desirable action to cause such insurers to pay, on behalf of the Agent, all amounts payable as a result of such proceeding in accordance with the terms of such policies.

(c) [The Corporation hereby acknowledges that Agent has certain rights to indemnification, advancement of expenses and/or insurance provided by Atlas Venture Fund VII, L.P. and certain of its affiliates (collectively, the “Fund Indemnitors”). The Corporation hereby agrees (i) that it is the indemnitor of first resort (i.e., its obligations to Agent are primary and any obligation of the Fund Indemnitors to advance expenses or to provide indemnification for the same expenses or liabilities incurred by Agent are secondary), (ii) that it shall be required to advance the full amount of expenses incurred by Agent and shall be liable for the full amount of all expenses, judgments, penalties, fines and amounts paid in settlement to the extent legally permitted and as required by the terms of this Agreement and the Certificate of Incorporation or Bylaws (or any other agreement between the Corporation and Agent), without regard to any rights Agent may have against the Fund Indemnitors, and, (iii) that it irrevocably waives, relinquishes and releases the Fund Indemnitors from any and all claims against the Fund Indemnitors for contribution, subrogation or any other recovery of any kind in respect thereof. The Corporation further agrees that no advancement or payment by the Fund Indemnitors on behalf of Agent with respect to any claim for which Agent has sought indemnification from the

Corporation shall affect the foregoing and the Fund Indemnitors shall have a right of contribution and/or be subrogated to the extent of such advancement or payment to all of the rights of recovery of Indemnitee against the Corporation. The Corporation and Agent agree that the Fund Indemnitors are express third party beneficiaries of the terms of this Section 11(c) .]

12. Survival of Rights.

(a) The rights conferred on Agent by this Agreement shall continue after Agent has ceased to be a director, officer, employee or other agent of the Corporation or to serve at the request of the Corporation as a director, officer, employee or other agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise and shall inure to the benefit of Agent’s heirs, executors and administrators.

(b) The Corporation shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business or assets of the Corporation, expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Corporation would be required to perform if no such succession had taken place.

13. Separability. Each of the provisions of this Agreement is a separate and distinct agreement and independent of the others, so that if any provision hereof shall be held to be invalid for any reason, such invalidity or unenforceability shall not affect the validity or enforceability of the other provisions hereof. Furthermore, if this Agreement shall be invalidated in its entirety on any ground, then the Corporation shall nevertheless indemnify Agent to the fullest extent provided by the Bylaws, the Code or any other applicable law.

14. Governing Law. This Agreement shall be interpreted and enforced in accordance with the laws of the State of Delaware.

15. Amendment and Termination. No amendment, modification, termination or cancellation of this Agreement shall be effective unless in writing signed by both parties hereto.

16. Identical Counterparts; Facsimile Delivery. This Agreement may be executed in one or more counterparts, each of which shall for all purposes be deemed to be an original but all of which together shall constitute but one and the same Agreement. Only one such counterpart need be produced to evidence the existence of this Agreement. This Agreement may be delivered via facsimile.

17. Headings. The headings of the sections of this Agreement are inserted for convenience only and shall not be deemed to constitute part of this Agreement or to affect the construction hereof.

18. Notices. All notices, requests, demands and other communications hereunder shall be in writing and shall be deemed to have been duly given (i) upon delivery if delivered by hand to the party to whom such communication was directed or (ii) upon the third business day after the date on which such communication was mailed if mailed by certified or registered mail with postage prepaid:

(a) If to Agent, at the address indicated on the signature page hereof.

(b) If to the Corporation, to:

ARCA biopharma, Inc.

8001 Arista Place, Suite 200

Broomfield, CO 80021

Attention: Chief Executive Officer and General Counsel

or to such other addresses as may have been furnished to Agent by the Corporation or the Corporation by Agent.

[remainder of page intentionally blank]

I N W ITNESS W HEREOF , the parties hereto have executed this Agreement on and as of the day and year first above written.


ARCA BIOPHARMA , I NC .

By:

Title:


A GENT


Print Name:


Address:

Exhibit 21.1

ARCA BIOPHARMA, INC.

LIST OF SUBSIDIARIES

1.	Hyseq Diagnostics, Inc., a Nevada corporation. ⁽ ¹⁾

2.	ARCA biopharma Colorado, Inc., a Delaware corporation. ⁽ ²⁾

(1)	Was the registrant’s sole subsidiary as of December 31, 2008.

(2)	Became a subsidiary of the registrant on January 27, 2009.

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the registration statements on Form S-3 (Nos. 333-148288, 333-131392, 333-128316, 333-126591, 333-118821, 333-112209, 333-106873, 333-103257, 333-90458 and 333-70134) and the registration statements on Form S-8 (Nos. 333-146078, 333-134981, 333-126590, 333-115747, 333-108563, 333-103055, 333-101276, 333-96313, 333-91471, 333-68172, 333-68170, 333-53089, 333-53087, 333-41663, 333-39194, 333-08978 and 333-154839) of ARCA biopharma, Inc. and in the related Prospectuses of our report dated March 25, 2009, with respect to the consolidated financial statements of ARCA biopharma, Inc. (formerly known as Nuvelo, Inc.) included in this Annual Report (Form 10-K) for the year ended December 31, 2008.

/s/ Ernst & Young LLP

Palo Alto, California

March 25, 2009

Exhibit 31.1

CERTIFICATION

I, Richard B. Brewer, certify that:

1.	I have reviewed this annual report on Form 10-K of ARCA biopharma, Inc. (formerly known as Nuvelo, Inc.);

Based on my knowledge, this annual report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this annual report;

3.	Based on my knowledge, the financial statements, and other financial information included in this annual report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this annual report;

The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

designed such disclosure controls and procedures or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this annual report is being prepared;

designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in the report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this annual report based on such evaluation;

disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.	The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: March 27, 2009

/s/ R ICHARD B. B REWER

Richard B. Brewer

President and Chief Executive Officer

Exhibit 31.2

CERTIFICATION

I, Kathryn E. Falberg, certify that:

1.	I have reviewed this annual report on Form 10-K of ARCA biopharma, Inc. (formerly known as Nuvelo, Inc.);

3.	Based on my knowledge, the financial statements, and other financial information included in this annual report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this annual report;

5.	The registrant’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: March 27, 2009

/s/ K ATHRYN E. F ALBERG

Kathryn E. Falberg

Chief Financial Officer

Exhibit 32.1

ARCA BIOPHARMA, INC.

(FORMERLY KNOWN AS NUVELO, INC.)

CERTIFICATION PURSUANT TO

18 U.S.C. SEC. 1350

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350), Richard B. Brewer, Chief Executive Officer of ARCA biopharma, Inc. (formerly known as Nuvelo, Inc.) (the “Company”), and Kathryn E. Falberg, Chief Financial Officer of the Company, each hereby certifies that, to the best of his or her knowledge:

(1)

The Company’s Annual Report on Form 10-K for the period ended December 31, 2008, to which this Certification is attached as Exhibit 32.1 (the “Annual Report”) fully complies with the requirements of Section 13(a) or Section 15(d) of the Exchange Act, and

(2)

The information contained in the Annual Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

In Witness Whereof , the undersigned have set their hands hereto as of the 27th day of March, 2009.

/s/ R ICHARD B. B REWER

/s/ K ATHRYN E. F ALBERG

Richard B. Brewer

President and Chief Executive Officer

Kathryn E. Falberg

Chief Financial Officer

“This certification accompanies the Form 10-K to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of ARCA biopharma, Inc. (formerly known as Nuvelo, Inc.) under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-K), irrespective of any general incorporation language contained in such filing.”

Date: March 27, 2009