Exhibit 1.1

EXECUTION VERSION

14,000,000 Shares

and

Warrants to Purchase 14,000,000 Shares of Common Stock

CONTRAFECT CORPORATION

Common Stock

PURCHASE AGREEMENT

July 22, 2016

PIPER JAFFRAY & CO.

    As Representative of the several

    Underwriters named in Schedule I hereto

c/o Piper Jaffray & Co.

U.S. Bancorp Center

800 Nicollet Mall

Minneapolis, Minnesota 55402

Ladies and Gentlemen:

ContraFect Corporation, a Delaware corporation (the “Company” ) proposes to sell to the several Underwriters named in Schedule I hereto (the “Underwriters” ) an aggregate of (i) 14,000,000 shares (the “Shares” ) of Common Stock, $0.0001 par value per share (the “Common Stock” ), of the Company and (ii) warrants to purchase up to 14,000,000 shares of Common Stock in the form set forth in Exhibit A (each, a “ Warrant ”). Each Share is being sold together with a Warrant to purchase one share of Common Stock at an exercise price of $3.00 per whole share of Common Stock. The Shares and Warrants are collectively called the “Securities.” The shares of Common Stock underlying the Warrants are called the “Warrant Shares.”

The Company hereby confirms its agreement with respect to the sale of the Securities to the several Underwriters, for whom Piper Jaffray & Co. is acting as representative (the “Representative” ).

1. Registration Statement and Prospectus . The Company has prepared and filed with the Securities and Exchange Commission (the “Commission” ) a registration statement on Form S-3 (File No. 333-211748) under the Securities Act of 1933, as amended (the “Securities Act” or “Act” ), and the rules and regulations (the “Rules and Regulations” ) of the Commission thereunder, and such amendments to such registration statement as may have been required to the date of this Agreement. Such registration statement has been declared effective by the Commission. Each part of such registration statement, including the amendments, exhibits and any schedules thereto, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act and the documents and information otherwise deemed to be a part thereof or included therein by

Rule 430B under the Securities Act (the “Rule 430B Information” ) or otherwise pursuant to the Rules and Regulations, as of the time the Registration Statement became effective, is herein called the “Registration Statement.” Any registration statement filed by the Company pursuant to Rule 462(b) under the Securities Act is called the “Rule 462(b) Registration Statement” and, from and after the date and time of filing of the Rule 462(b) Registration Statement, the term “Registration Statement” shall include the Rule 462(b) Registration Statement.

The prospectus in the form in which it has most recently been filed with the Commission on or prior to the date of this Agreement is herein called the “Base Prospectus.” Each preliminary prospectus supplement to the Base Prospectus (including the Base Prospectus as so supplemented), that describes the Securities and the offering thereof, that omitted the Rule 430B Information and that was used prior to the filing of the final prospectus supplement referred to in the following sentence is herein called a “Preliminary Prospectus.” Promptly after execution and delivery of this Agreement, the Company will prepare and file with the Commission a final prospectus supplement to the Base Prospectus relating to the Securities and the offering thereof in accordance with the provisions Rule 430B and Rule 424(b) of the Rules and Regulations. Such final supplemental form of prospectus (including the Base Prospectus as so supplemented), in the form filed with the Commission pursuant to Rule 424(b) is herein called the “Prospectus.” Any reference herein to the Base Prospectus, any Preliminary Prospectus or the Prospectus shall be deemed to refer to include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act as of the date of such prospectus.

For purposes of this Agreement, all references to the Registration Statement, the Rule 462(b) Registration Statement, the Base Prospectus, any Preliminary Prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System or any successor system thereto. All references in this Agreement to financial statements and schedules and other information which is “described,” “contained,” “included” or “stated” in the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Prospectus (or other references of like import) shall be deemed to mean and include all such financial statements and schedules and other information which is incorporated by reference in or otherwise deemed by the Rules and Regulations to be a part of or included in the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Prospectus, as the case may be; and all references in this Agreement to amendments or supplements to the Registration Statement, the Base Prospectus, any Preliminary Prospectus or the Prospectus shall be deemed to mean and include the subsequent filing of any document under the Securities Exchange Act of 1934, as amended (the “Exchange Act” ) and which is deemed to be incorporated therein by reference therein or otherwise deemed by the Rules and Regulations to be a part thereof.

2. Representations and Warranties of the Company .

(a) Representations and Warranties of the Company . The Company represents and warrants to, and agrees with, the several Underwriters as follows:

(i) Registration Statement and Prospectuses . No order preventing or suspending the use of any Preliminary Prospectus or the Prospectus (or any supplement

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thereto) has been issued by the Commission and no proceeding for that purpose has been initiated or is pending or, to the knowledge of the Company, threatened by the Commission. As of the time each part of the Registration Statement (or any post-effective amendment thereto) became or becomes effective (including each deemed effective date with respect to the Underwriters pursuant to Rule 430B or otherwise under the Securities Act), such part conformed or will conform in all material respects to the requirements of the Act and the Rules and Regulations. Upon the filing or first use within the meaning of the Rules and Regulations, each Preliminary Prospectus and the Prospectus (or any supplement to either) conformed or will conform in all material respects to the requirements of the Act and the Rules and Regulations. The Registration Statement and any post-effective amendment thereto has become effective under the Securities Act. The Company has complied to the Commission’s satisfaction with all requests of the Commission for additional or supplemental information. No stop order suspending the effectiveness of the Registration Statement , any post-effective amendment or any part thereof is in effect and no proceedings for such purpose have been instituted or are pending or, to the knowledge of the Company, are threatened by the Commission.

(ii) Accurate Disclosure . Each Preliminary Prospectus, at the time of filing thereof or the time of first use within the meaning of the Rules and Regulations, did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. Neither the Registration Statement nor any amendment thereto, at the effective time of each part thereof, at the Closing Date (as defined below) , contained, contains or will contain an untrue statement of a material fact or omitted, omits or will omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. As of the Time of Sale (as defined below), neither (A) the Time of Sale Disclosure Package (as defined below) nor (B) any issuer free writing prospectus (as defined below), when considered together with the Time of Sale Disclosure Package, included an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. Neither the Prospectus nor any supplement thereto, as of its issue date, at the time of any filing with the Commission pursuant to Rule 424(b) of the Rules and Regulations, at the Closing Date, included, includes or will include an untrue statement of a material fact or omitted, omits or will omit to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. The representations and warranties in this Section 2(a)(ii) shall not apply to statements in or omissions from any Preliminary Prospectus, the Registration Statement (or any amendment thereto), the Time of Sale Disclosure Package or the Prospectus (or any supplement thereto) made in reliance upon, and in conformity with, written information furnished to the Company by you, or by any Underwriter through you, specifically for use in the preparation of such document, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 6(e).

Each reference to an “issuer free writing prospectus” herein means an issuer free writing prospectus as defined in Rule 433 of the Rules and Regulations.

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“Time of Sale Disclosure Package” means the Preliminary Prospectus dated July 22, 2016, any free writing prospectus set forth on Schedule II and the information on Schedule III, all considered together.

Each reference to a “free writing prospectus” herein means a free writing prospectus as defined in Rule 405 of the Rules and Regulations.

“Time of Sale” means 8:30 a.m. (Eastern time) on the date of this Agreement.

(iii) Issuer Free Writing Prospectuses . (A) Each Issuer Free Writing Prospectus does not include any information that conflicts with the information contained in the Registration Statement, any Preliminary Prospectus or the Prospectus. The foregoing sentence does not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by you or by any Underwriter through you specifically for use therein; it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 6(e).

(B) (1) At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Securities and (2) at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 under the Securities Act, including the Company in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405 of the Rules and Regulations (without taking account of any determination by the Commission pursuant to Rule 405 of the Rules and Regulations that it is not necessary that the Company be considered an ineligible issuer), nor an “excluded issuer” as defined in Rule 164 under the Securities Act.

(C) Each Issuer Free Writing Prospectus satisfied, as of its issue date and at all subsequent times to the Time of Sale, all other conditions to use thereof as set forth in Rules 164 and 433 under the Securities Act.

(iv) No Other Offering Materials . The Company has not distributed and will not distribute any prospectus or other offering material in connection with the offering and sale of the Securities other than any Preliminary Prospectus, the Time of Sale Disclosure Package or the Prospectus or other materials permitted by the Act to be distributed by the Company; provided, however, that, except as set forth on Schedule II, the Company has not made and will not make any offer relating to the Securities that would constitute a free writing prospectus, except in accordance with the provisions of Section 4(a)(xv) of this Agreement.

(v) Financial Statements . The financial statements of the Company, together with the related notes, set forth or incorporated by reference in the Registration

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Statement, the Time of Sale Disclosure Package and the Prospectus comply in all material respects with the requirements of the Securities Act and the Exchange Act and fairly present the financial condition of the Company as of the dates indicated and the results of operations and changes in cash flows for the periods therein specified in conformity with generally accepted accounting principles in the United States consistently applied throughout the periods involved; the supporting schedules included in the Registration Statement present fairly the information required to be stated therein; all non-GAAP financial information included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus complies with the requirements of Regulation G and Item 10 of Regulation S-K under the Act; and, except as disclosed in the Time of Sale Disclosure Package and the Prospectus, there are no material off-balance sheet arrangements (as defined in Regulation S-K under the Act, Item 303(a)(4)(ii)) or any other relationships with unconsolidated entities or other persons, that may have a material current or, to the Company’s knowledge, material future effect on the Company’s financial condition, results of operations, liquidity, capital expenditures, capital resources or significant components of revenue or expenses. No other financial statements or schedules are required to be included in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus. To the Company’s knowledge, Ernst & Young LLP, which has expressed its opinion with respect to the financial statements and schedules filed as a part of the Registration Statement and included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, is (x) an independent public accounting firm within the meaning of the Act and the Rules and Regulations, (y) a registered public accounting firm (as defined in Section 2(a)(12) of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act” )) and (z) not in violation of the auditor independence requirements of the Sarbanes-Oxley Act.

(vi) Organization and Good Standing . The Company has been duly organized and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation. The Company has full corporate power and authority to own its properties and conduct its business as currently being carried on and as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, and is duly qualified to do business as a foreign corporation in good standing in each jurisdiction in which it owns or leases real property or in which the conduct of its business makes such qualification necessary and in which the failure to so qualify would have a material adverse effect upon the business, prospects, management, properties, operations, condition (financial or otherwise) or results of operations of the Company ( “Material Adverse Effect” ).

(vii) Absence of Certain Events . Except as contemplated in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, the Company has not incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there has not been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants or conversion of convertible securities), or any material change in the short-term or long-term debt (other than as a result of the conversion of convertible securities), or any issuance of options, warrants, convertible

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securities or other rights to purchase the capital stock, of the Company or any Material Adverse Effect or any development which could reasonably be expected to result in any Material Adverse Effect.

(viii) Absence of Proceedings . Except as set forth in the Time of Sale Disclosure Package and in the Prospectus, there is not pending or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding (a) to which the Company is a party or (b) which has as the subject thereof any officer or director of the Company, any employee benefit plan sponsored by the Company or any property or assets owned or leased by the Company before or by any court or Governmental Authority (as defined below), or any arbitrator, which, individually or in the aggregate, might result in any Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement or which are otherwise material in the context of the sale of the Securities. There are no current or, to the knowledge of the Company, pending, legal, governmental or regulatory actions, suits or proceedings (x) to which the Company is subject or (y) which has as the subject thereof any officer or director of the Company, any employee plan sponsored by the Company or any property or assets owned or leased by the Company, that are required to be described in the Registration Statement, Time of Sale Disclosure Package and Prospectus by the Act or by the Rules and Regulations and that have not been so described.

(ix) Authorization; No Conflicts; Authority . This Agreement has been duly authorized, executed and delivered by the Company, and constitutes a valid, legal and binding obligation of the Company, enforceable in accordance with its terms, except as rights to indemnity hereunder may be limited by federal or state securities laws and except as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of creditors generally and subject to general principles of equity. The warrant agreement governing the Warrants (the “Warrant Agreement” ) to be dated as of the Closing Date and entered into by and between the Company and American Stock Transfer & Trust Company (the “Warrant Agent” ), has been duly authorized by the Company and, when executed and delivered by the Company and the Warrant Agent, will be a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of creditors generally and subject to general principles of equity. The execution, delivery and performance of this Agreement and the Warrant Agreement, and the consummation of the transactions herein contemplated will not (A) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company is a party or by which the Company is bound or to which any of the property or assets of the Company is subject, (B) result in any violation of the provisions of the Company’s charter or by-laws or (C) result in the violation of any law or statute or any judgment, order, rule, regulation or decree of any court or arbitrator or federal, state, local or foreign governmental agency or regulatory authority having jurisdiction over the Company or any of its properties or assets (each, a “Governmental Authority” ), except in the case of

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clauses (A) or (C) as would not, individually or in the aggregate, reasonably be likely to result in a Material Adverse Effect. No consent, approval, authorization or order of, or registration or filing with any Governmental Authority is required for the execution, delivery and performance of this Agreement or for the consummation of the transactions contemplated hereby, including the issuance or sale of the Securities by the Company and the issuance of the Warrant Shares upon exercise of the Warrants, except such as may be required under the Act , the rules of the Financial Industry Regulatory Authority ( “FINRA” ) or state securities or blue sky laws; and the Company has full power and authority to enter into this Agreement and the Warrant Agreement and to consummate the transactions contemplated hereby and thereby, including the authorization, issuance and sale of the Securities as contemplated by this Agreement and the issuance of the Warrant Shares upon exercise of the Warrants.

(x) Capitalization; the Securities; Registration Rights . All of the issued and outstanding shares of capital stock of the Company, including the outstanding shares of Common Stock, is duly authorized and validly issued, fully paid and nonassessable, have been issued in compliance with all federal and state securities laws, were not issued in violation of or subject to any preemptive rights or other rights to subscribe for or purchase securities that have not been waived in writing (a copy of which has been delivered to counsel to the Representative), and the holders thereof are not subject to personal liability by reason of being such holders; the Securities which may be sold hereunder by the Company have been duly authorized and, when issued, delivered and paid for in accordance with the terms of this Agreement, will have been validly issued and will be fully paid and nonassessable, and the holders thereof will not be subject to personal liability by reason of being such holders; the Warrants which may be sold hereunder by the Company have been duly authorized for issuance and sale by the Company and, when executed, issued and delivered and fully paid for in accordance with the terms of this Agreement, will constitute legal, valid and binding obligations of the Company, enforceable in accordance with their terms, except as the enforceability thereof may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of creditors generally and subject to general principles of equity; the Warrant Shares have been duly authorized and reserved for issuance pursuant to the terms of the Warrants, and when issued by the Company upon valid exercise of the Warrants and payment of the exercise price, will be validly issued, fully paid and nonassessable and the capital stock of the Company, including the Common Stock, conforms to the description thereof in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus. Except as otherwise described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, there are no preemptive rights or other rights to subscribe for or to purchase, or any restriction upon the voting or transfer of, any shares of Common Stock pursuant to the Company’s charter, by-laws or any agreement or other instrument to which the Company is a party or by which the Company is bound other than options to purchase common stock under the Company’s existing stock option plans. Except as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, neither the filing of the Registration Statement nor the offering or sale of the Securities as contemplated by this Agreement gives rise to any rights for or relating to the registration of any shares of Common Stock or other securities

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of the Company that have not been fully complied with or previously waived. The Company has an authorized and outstanding capitalization as set forth in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, as of the dates set forth therein. The Common Stock (including the Securities and the Warrant Shares) conforms in all material respects to the description thereof contained in the Time of Sale Disclosure Package and the Prospectus.

(xi) Stock Options . Except as described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, there are no options, warrants, agreements, contracts or other rights in existence to purchase or acquire from the Company any shares of the capital stock of the Company. The description of the Company’s stock option, stock bonus and other stock plans or arrangements, and the options or other rights granted thereunder, set forth in the Time of Sale Disclosure Package and the Prospectus accurately and fairly presents the information required to be shown with respect to such plans, arrangements, options and rights.

(xii) Compliance with Laws . The Company holds, and is operating in compliance in all material respects with, all franchises, grants, authorizations, licenses, permits, easements, consents, certificates and orders of any Governmental Authority required for the conduct of its business as currently conducted (collectively, the “ Permits ”) and all such Permits are valid and in full force and effect; and the Company has not received written notice of any revocation of any such Permit or written notice of any modification of any such Permit that would result in a Material Adverse Effect, nor has reason to believe that any such Permit will not be renewed in the ordinary course; and the Company is in compliance in all material respects with all applicable federal, state, local and foreign laws and regulations.

(xiii) Ownership of Assets . The Company has good and marketable title to all property (whether real or personal) that is material to the business and is described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus as being owned by it, in each case free and clear of all liens, claims, security interests, other encumbrances or defects except such as (a) are described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus or (b) would not, individually or in the aggregate, reasonably be likely to result in a Material Adverse Effect. The property held under lease by the Company is held by it under valid, subsisting and enforceable leases with only such exceptions with respect to any particular lease as do not interfere in any material respect with the conduct of the business of the Company.

(xiv) Intellectual Property . Except as disclosed in the Registration Statement, Time of Sale Disclosure Package and the Prospectus, the Company licenses, owns, possesses, or can acquire on reasonable terms, all Intellectual Property necessary for the conduct of the Company’s business as now conducted or as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus to be conducted, except as such failure to license, own, possess, or acquire such rights would not result in a Material Adverse Effect. Furthermore, (A) to the knowledge of the Company, there is no infringement, misappropriation or violation by third parties of any such Intellectual

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Property, except as such infringement, misappropriation or violation would not result in a Material Adverse Effect; (B) there is no pending or, to the knowledge of the Company, threatened, action, suit, proceeding or claim by others challenging the Company’s rights in or to any such Intellectual Property, and the Company is unaware of any facts which would form a reasonable basis for any such claim; (C) the Intellectual Property owned by the Company, and to the knowledge of the Company, the Intellectual Property licensed to the Company, has not been adjudged invalid or unenforceable, in whole or in part, and there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others (excluding with respect to ordinary course interactions with patent authorities during patent prosecution) challenging the validity or scope of any such Intellectual Property, and the Company is unaware of any facts which would form a reasonable basis for any such claim; (D) there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others that the Company infringes, misappropriates or otherwise violates any Intellectual Property or other proprietary rights of others, and the Company is unaware of any fact which would form a reasonable basis for any such claim; and (E) to the Company’s knowledge, no employee of the Company is in or has ever been in violation of any term of any employment contract, patent disclosure agreement, invention assignment agreement, non-competition agreement, non-solicitation agreement, nondisclosure agreement or any restrictive covenant to or with a former employer where the basis of such violation relates to such employee’s employment with the Company or actions undertaken by the employee while employed with the Company, except as such violation would not result in a Material Adverse Effect. “Intellectual Property” shall mean all patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, trade secrets, domain names, technology, know-how and other intellectual property.

(xv) Clinical Trials and Studies . The studies, tests and preclinical and clinical trials conducted by or on behalf of, or sponsored by, the Company, or in which the Company has participated, that are described in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus, or the results of which are referred to in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus, were and, if still pending, are being conducted in all material respects in accordance with all applicable statutes, rules and regulations of the FDA, the European Medicines Agency (the “ EMA ”) and other comparable drug and medical device (including diagnostic product) regulatory agencies outside of the United States to which they are subject; the descriptions of the results of such studies, tests and trials contained in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus do not contain any misstatement of a material fact or omit to state a material fact necessary to make such statements not misleading in any material respect; the Company has no knowledge of any studies, tests or trials not described in the Disclosure Package and the Prospectus the results of which reasonably call into question in any material respect the results of the studies, tests and trials described in the Registration Statement, the Time of Sale Disclosure Package or Prospectus; and the Company has not received any written notices or other written correspondence from the FDA, EMA or any other foreign, state or local governmental body exercising comparable authority or any institutional review board or comparable authority requiring or threatening the termination, suspension or material

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modification of any studies, tests or preclinical or clinical trials conducted by or on behalf of, or sponsored by, the Company or in which the Company has participated, and, to the Company’s knowledge, there are no reasonable grounds for the same.

(xvi) No Violations or Defaults . The Company is not in violation of its charter, by-laws or other organizational documents, or in breach of or otherwise in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default in the performance of any material obligation, agreement or condition contained in any bond, debenture, note, indenture, loan agreement or any other material contract, lease or other instrument to which it is subject or by which it may be bound, or to which any of the material property or assets of the Company is subject.

(xvii) Taxes . The Company have timely filed all federal, state, local and foreign income and franchise tax returns required to be filed and are not in default in the payment of any taxes which were payable pursuant to said returns or any assessments with respect thereto, other than any which the Company is contesting in good faith, except where the failure to file such tax returns or to pay such taxes would not result in a Material Adverse Effect. There is no pending dispute with any taxing authority relating to any of such returns, and the Company has no knowledge of any proposed liability for any tax to be imposed upon the properties or assets of the Company for which there is not an adequate reserve reflected in the Company’s financial statements included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus.

(xviii) Exchange Listing and Exchange Act Registration . The Common Stock is registered pursuant to Section 12(b) of the Exchange Act and is included or approved for listing on the Nasdaq Capital Market (“ Nasdaq ”) and the Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Common Stock under the Exchange Act or delisting the Common Stock from Nasdaq nor has the Company received any written notification that the Commission or Nasdaq is contemplating terminating such registration or listing. The Company has complied in all material respects with the applicable requirements of Nasdaq for maintenance of inclusion of the Common Stock thereon. The Securities and Warrant Shares, when issued, will be listed on Nasdaq. Except as previously disclosed to counsel for the Underwriters or as set forth in the Time of Sale Disclosure Package and the Prospectus, to the knowledge of the Company, no beneficial owners of the Company’s capital stock or subordinated debt who, together with their associated persons and affiliates, hold in the aggregate 10% or more of such capital stock or subordinated debt, have any direct or indirect association or affiliate with a FINRA member.

(xix) Ownership of Other Entities . The Company does not, directly or indirectly, own any capital stock or other equity or ownership or proprietary interest in any corporation, partnership, association, trust or other entity.

(xx) Internal Controls . The Company maintains a system of internal accounting controls sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management’s general or specific authorization;

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(ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles in the United States and to maintain accountability for assets; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, the Company’s internal control over financial reporting is effective and none of the Company, its board of directors and audit committee is aware of any “significant deficiencies” or “material weaknesses” (each as defined by the Public Company Accounting Oversight Board) in its internal control over financial reporting, or any fraud, whether or not material, that involves management or other employees of the Company who have a significant role in the Company’s internal controls; and since the end of the latest audited fiscal year, there has been no change in the Company’s internal control over financial reporting (whether or not remediated) that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting. The Company’s board of directors has, subject to the exceptions, cure periods and the phase in periods specified in the applicable stock exchange rules ( “Exchange Rules” ), validly appointed an audit committee to oversee internal accounting controls whose composition satisfies the applicable requirements of the Exchange Rules and the Company’s board of directors and/or the audit committee has adopted a charter that satisfies the requirements of the Exchange Rules.

(xxi) No Brokers or Finders . Other than as contemplated by this Agreement, the Company has not incurred any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the Warrant Agreement (other than fees and/or commissions paid or payable to the Warrant Agent for performing services as warrant agent) or the consummation of the transactions contemplated hereby and thereby.

(xxii) Insurance . The Company carries, or is covered by, insurance from reputable insurers in such amounts and covering such risks as is adequate for the conduct of its business and the value of its properties and as is customary for companies engaged in similar businesses in similar industries; all policies of insurance and any fidelity or surety bonds insuring the Company or its business, assets, employees, officers and directors are in full force and effect; the Company is in compliance with the terms of such policies and instruments in all material respects; there are no claims by the Company under any such policy or instrument as to which any insurance company is denying liability or defending under a reservation of rights clause; the Company has not been refused any insurance coverage sought or applied for; and the Company has no reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a Material Adverse Effect.

(xxiii) Investment Company Act . The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company,” as such term is defined in the Investment Company Act of 1940, as amended.

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(xxiv) Eligibility to use Form S-3 . The conditions for use of Form S-3, set forth in the General Instructions thereto, have been satisfied.

(xxv) Incorporated Documents . The documents incorporated by reference in the Time of Sale Disclosure Package and in the Prospectus, when they became effective or were filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and were filed on a timely basis with the Commission and none of such documents contained an untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; any further documents so filed and incorporated by reference in the Time of Sale Disclosure Package or in the Prospectus, when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act, and will not contain an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(xxvi) Sarbanes-Oxley Act . The Company is in compliance with all applicable provisions of the Sarbanes-Oxley Act and the rules and regulations of the Commission thereunder.

(xxvii) Disclosure Controls . The Company has established and maintains disclosure controls and procedures (as defined in Rules 13a-14 and 15d-14 under the Exchange Act) and such controls and procedures are effective in ensuring that material information relating to the Company is made known to the principal executive officer and the principal financial officer. The Company has utilized such controls and procedures in preparing and evaluating the disclosures in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus.

(xxviii) Anti-Bribery and Anti-Money Laundering Laws . Each of the Company, its affiliates and any of their respective officers, directors, supervisors, managers, agents, or employees, has not violated, its participation in the offering will not violate, and the Company has instituted and maintains policies and procedures designed to ensure continued compliance with, each of the following laws: anti-bribery laws, including but not limited to, any applicable law, rule, or regulation of any locality, including but not limited to any law, rule, or regulation promulgated to implement the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, signed December 17, 1997, including the U.S. Foreign Corrupt Practices Act of 1977, as amended, the U.K. Bribery Act 2010, or any other law, rule or regulation of similar purposes and scope, or anti-money laundering laws, including but not limited to, applicable federal, state, international, foreign or other laws, regulations or government guidance regarding anti-money laundering, including, without limitation, Title 18 US. Code section 1956 and 1957, the Patriot Act, the Bank Secrecy Act, and international anti-money laundering principles or procedures by an intergovernmental group or organization, such as the Financial Action Task Force on Money Laundering, of which the United States is a member and with which

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designation the United States representative to the group or organization continues to concur, all as amended, and any Executive order, directive, or regulation pursuant to the authority of any of the foregoing, or any orders or licenses issued thereunder.

(xxix) OFAC .

(A) Neither the Company nor any of its directors, officers or employees, nor, to the Company’s knowledge, any agent, affiliate or representative of the Company, is an individual or entity that is, or is owned or controlled by an individual or entity that is:

(1) the subject of any sanctions administered or enforced by the U.S. Department of Treasury’s Office of Foreign Assets Control, the United Nations Security Council, the European Union, Her Majesty’s Treasury (collectively, “Sanctions” ), nor

(2) operating from, organized in, or resident in a country or territory that is the subject of Sanctions (at the time of the Agreement, the Crimea region of Ukraine, Cuba, Iran, North Korea, Sudan and Syria).

(B) The Company will not, directly or indirectly, use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other individual or entity:

(1) to fund or facilitate any activities or business of or with any individual or entity or in any country or territory that, at the time of such funding or facilitation, is the subject of comprehensive Sanctions; or

(2) in any other manner that will result in a violation of comprehensive Sanctions by any individual or entity (including any individual or entity participating in the offering, whether as underwriter, advisor, investor or otherwise).

(C) For the past five years, the Company has not knowingly engaged in, and is not now knowingly engaged in, any dealings or transactions with any individual or entity, or in any country or territory, that at the time of the dealing or transaction is or was the subject of Sanctions.

(xxx) Compliance with Environmental Laws . Except as disclosed in the Time of Disclosure Package and the Prospectus, the Company is not in violation of any statute, any rule, regulation, decision or order of any Governmental Authority or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “Environmental Laws” ), owns

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or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any Environmental Laws, or is subject to any claim relating to any Environmental Laws, which violation, contamination, liability or claim would individually or in the aggregate, have a Material Adverse Effect; and the Company is not aware of any pending investigation which might lead to such a claim. The Company does not anticipate incurring any material capital expenditures relating to compliance with Environmental Laws.

(xxxi) Compliance with Occupational Laws . The Company (A) is in compliance, in all material respects, with any and all applicable foreign, federal, state and local laws, rules, regulations, treaties, statutes and codes promulgated by any and all Governmental Authorities (including pursuant to the Occupational Health and Safety Act) relating to the protection of human health and safety in the workplace ( “Occupational Laws” ); (B) has received all material permits, licenses or other approvals required of it under applicable Occupational Laws to conduct its business as currently conducted; and (C) is in compliance, in all material respects, with all terms and conditions of such permit, license or approval. No action, proceeding, revocation proceeding, writ, injunction or claim is pending or, to the Company’s knowledge, threatened against the Company relating to Occupational Laws, and the Company does not have knowledge of any facts, circumstances or developments relating to its operations or cost accounting practices that could reasonably be expected to form the basis for or give rise to such actions, suits, investigations or proceedings.

(xxxii) ERISA and Employee Benefits Matters . (A) To the knowledge of the Company, no “prohibited transaction” as defined under Section 406 of ERISA or Section 4975 of the Code and not exempt under ERISA Section 408 and the regulations and published interpretations thereunder has occurred with respect to any Employee Benefit Plan. At no time has the Company or any ERISA Affiliate maintained, sponsored, participated in, contributed to or has or had any liability or obligation in respect of any Employee Benefit Plan subject to Part 3 of Subtitle B of Title I of ERISA, Title IV of ERISA, or Section 412 of the Code or any “multiemployer plan” as defined in Section 3(37) of ERISA or any multiple employer plan for which the Company or any ERISA Affiliate has incurred or could incur liability under Section 4063 or 4064 of ERISA. No Employee Benefit Plan provides or promises, or at any time provided or promised, retiree health, life insurance, or other retiree welfare benefits except as may be required by the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended, or similar state law. Each Employee Benefit Plan is and has been operated in material compliance with its terms and all applicable laws, including but not limited to ERISA and the Code and, to the knowledge of the Company, no event has occurred (including a “reportable event” as such term is defined in Section 4043 of ERISA) and no condition exists that would subject the Company or any ERISA Affiliate to any material tax, fine, lien, penalty or liability imposed by ERISA, the Code or other applicable law, except as would not reasonably be expected to have a Material Adverse Effect. Each Employee Benefit Plan intended to be qualified under Code Section 401(a) is so qualified and has a favorable determination or opinion letter from the IRS upon which it can rely, and any

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such determination or opinion letter remains in effect and has not been revoked; to the knowledge of the Company, nothing has occurred since the date of any such determination or opinion letter that is reasonably likely to adversely affect such qualification; (B) the Company does not have any obligations under any collective bargaining agreement with any union and, to the knowledge of the Company, no organization efforts are underway with respect to Company employees. As used in this Agreement, “Code” means the Internal Revenue Code of 1986, as amended; “Employee Benefit Plan” means any “employee benefit plan” within the meaning of Section 3(3) of ERISA, including, without limitation, all stock purchase, stock option, stock-based severance, employment, change-in-control, medical, disability, fringe benefit, bonus, incentive, deferred compensation, employee loan and all other employee benefit plans, agreements, programs, policies or other arrangements, whether or not subject to ERISA, under which (1) any current or former employee, director or independent contractor of the Company has any present or future right to benefits and which are contributed to, sponsored by or maintained by the Company or (2) the Company has had or has any present or future obligation or liability; “ERISA” means the Employee Retirement Income Security Act of 1974, as amended; “ERISA Affiliate” means any member of the company’s controlled group as defined in Code Section 414(b), (c), (m) or (o).

(xxxiii) Business Arrangements . Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company has not granted rights to develop, manufacture, produce, assemble, distribute, license, market or sell its products to any other person and is not bound by any agreement that affects the exclusive right of the Company to develop, manufacture, produce, assemble, distribute, license, market or sell its products.

(xxxiv) Labor Matters . No labor problem or dispute with the employees of the Company exists, or to the knowledge of the Company, or is threatened or imminent, and the Company is not aware of any existing or imminent labor disturbance by the employees of any of its principal suppliers, contractors or customers, that could have a Material Adverse Effect.

(xxxv) Statistical Information . Any third-party statistical and market-related data included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects.

(xxxvi) Forward-looking Statements . No forward-looking statement (within the meaning of Section 27A of the Act and Section 21E of the Exchange Act) contained in the Registration Statement, the Pricing Disclosure Package or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

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3. Purchase, Sale and Delivery of Securities .

(a) Securities . On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company agrees to issue and sell the Shares and Warrants to the several Underwriters, and each Underwriter agrees, severally and not jointly, to purchase from the Company the number of Shares and Warrants set forth opposite the name of such Underwriter in Schedule I hereto. The purchase price per combined Share and Warrant shall be $2.3375 per combined Share and Warrant. In making this Agreement, each Underwriter is contracting severally and not jointly; except as provided in paragraph (c) of this Section 3 and in Section 8 hereof, the agreement of each Underwriter is to purchase only the respective number of Shares and Warrants specified in Schedule I.

The Securities will be delivered by the Company to you for the accounts of the several Underwriters against payment of the purchase price therefor by wire transfer of same day funds payable to the order of the Company, as appropriate, at the offices of Piper Jaffray & Co., U.S. Bancorp Center, 800 Nicollet Mall, Minneapolis, Minnesota, or such other location as may be mutually acceptable, at 9:00 a.m. Central time on the third (or if the Securities are priced, as contemplated by Rule 15c6-1(c) under the Exchange Act, after 4:30 p.m. Eastern time, the fourth) full business day following the date hereof, or at such other time and date as you and the Company determine pursuant to Rule 15c6-1(a) under the Exchange Act, such time and date of delivery being herein referred to as the “Closing Date.”

(b) Purchase by Representative on Behalf of Underwriters . It is understood that you, individually and not as Representative of the several Underwriters, may (but shall not be obligated to) make payment to the Company on behalf of any Underwriter for the Securities to be purchased by such Underwriter. Any such payment by you shall not relieve any such Underwriter of any of its obligations hereunder. Nothing herein contained shall constitute any of the Underwriters an unincorporated association or partner with the Company.

4. Covenants .

(a) Covenants of the Company . The Company covenants and agrees with the several Underwriters as follows:

(i) Required Filings . During the period beginning on the date hereof and ending on the later of the Closing Date or such date, as in the opinion of counsel for the Underwriters, the Prospectus is no longer required by law to be delivered (assuming the absence of Rule 172 under the Securities Act), in connection with sales by an Underwriter or dealer (the “ Prospectus Delivery Period” ), prior to amending or supplementing the Registration Statement (including any Rule 462(b) Registration Statement), the Time of Sale Disclosure Package or the Prospectus, the Company shall furnish to the Representative for review a copy of each such proposed amendment or supplement, and the Company shall not file any such proposed amendment or supplement to which the Representative or counsel to the Underwriters reasonably object. Subject to this Section 4(a)(i), immediately following execution of this Agreement, the Company will prepare the Prospectus containing the Rule 430B

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Information and other selling terms of the Securities, the plan of distribution thereof and such other information as may be required by the Securities Act or the Rules and Regulations or as the Representative and the Company may deem appropriate, and if requested by the Representative, an issuer free writing prospectus containing the selling terms of the Securities and such other information as the Company and the Representative may deem appropriate, and will file or transmit for filing with the Commission, in accordance with Rule 424(b) or Rule 433, as the case may be, copies of the Prospectus and each issuer free writing prospectus.

(ii) Notification of Certain Commission Actions . After the date of this Agreement, the Company shall promptly advise the Representative in writing (A) of the receipt of any comments of, or requests for additional or supplemental information from, the Commission, (B) of the time and date of any filing of any post-effective amendment to the Registration Statement or any amendment or supplement to any Preliminary Prospectus, the Time of Sale Disclosure Package or the Prospectus, (C) of the time and date that any post-effective amendment to the Registration Statement becomes effective, (D) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto or of any order preventing or suspending its use or the use of any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus, or (E) of any proceedings to remove, suspend or terminate from listing or quotation the Common Stock from any securities exchange upon which it is listed for trading or included or designated for quotation, or of the threatening or initiation of any proceedings for any of such purposes. If the Commission shall enter any such stop order at any time, the Company will use its best efforts to obtain the lifting of such order at the earliest possible moment. Additionally, the Company agrees that it shall comply with the provisions of Rules 424(b), 430A and 430B, as applicable, under the Securities Act and will use its reasonable efforts to confirm that any filings made by the Company under Rule 424(b), Rule 433 or Rule 462 were received in a timely manner by the Commission (without reliance on Rule 424(b)(8) or Rule 164(b)).

(iii) Continued Compliance with Securities Laws . (A) During the Prospectus Delivery Period, the Company will comply as far as it is able with all requirements imposed upon it by the Securities Act, as now and hereafter amended, and by the Rules and Regulations, as from time to time in force, and by the Exchange Act so far as necessary to permit the continuance of sales of or dealings in the Securities as contemplated by the provisions hereof, the Time of Sale Disclosure Package and the Prospectus. If during such period any event occurs as a result of which the Prospectus (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) would include an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances then existing, not misleading, or if during such period it is necessary or appropriate in the opinion of the Company or its counsel or the Representative or counsel to the Underwriters to amend the Registration Statement or supplement the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) to comply with the Securities Act or to file under the Exchange Act any document which would be deemed to be incorporated by reference in the Prospectus in order to comply with the Securities Act or the

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Exchange Act, the Company promptly will (x) notify you of such untrue statement or omission, (y) amend the Registration Statement or supplement the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) or file such document (at the expense of the Company) so as to correct such statement or omission or effect such compliance, and (z) notify you when any amendment to the Registration Statement is filed or becomes effective or when any supplement to the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) is filed.

(B) If at any time following issuance of an issuer free writing prospectus there occurred or occurs an event or development as a result of which such issuer free writing prospectus conflicted or would conflict with the information contained in the Registration Statement, the Preliminary Prospectus or the Prospectus or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at that subsequent time, not misleading, the Company (x) has promptly notified or promptly will notify the Representative of such conflict, untrue statement or omission, (y) has promptly amended or will promptly amend or supplement, at its own expense, such issuer free writing prospectus to eliminate or correct such conflict, untrue statement or omission, and (z) has notified or promptly will notify you when such amendment or supplement was or is filed with the Commission where so required to be filed.

(iv) Blue Sky Qualifications . The Company shall take or cause to be taken all necessary action to qualify the Securities for sale under the securities laws of such jurisdictions as you reasonably designate and to continue such qualifications in effect so long as required for the distribution of the Securities, except that the Company shall not be required in connection therewith to qualify as a foreign corporation or to execute a general consent to service of process in any state.

(v) Provision of Documents . The Company will furnish, at its own expense, to the Underwriters and counsel for the Underwriters copies of the Registration Statement (which will include three complete manually signed copies of the Registration Statement and all consents and exhibits filed therewith), and to the Underwriters and any dealer each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus, and all amendments and supplements to such documents, in each case as soon as available and in such quantities as you may from time to time reasonably request.

(vi) Rule 158 . The Company will make generally available to its security holders as soon as practicable, but in no event later than 15 months after the end of the Company’s current fiscal quarter, an earnings statement (which need not be audited) covering a 12-month period that shall satisfy the provisions of Section 11(a) of the Securities Act and Rule 158 of the Rules and Regulations.

(vii) Payment and Reimbursement of Expenses . The Company, whether or not the transactions contemplated hereunder are consummated or this Agreement is

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otherwise terminated (but subject to clause I below), will pay or cause to be paid (A) all expenses (including transfer taxes allocated to the transferees) incurred in connection with the delivery to the Underwriters of the Securities, (B) all expenses and fees (including, without limitation, fees and expenses of the Company’s accountants and counsel, but excluding, for the avoidance of doubt, reasonable fees and disbursements of the Underwriters’ counsel, which shall be paid pursuant to clause (I) below) in connection with the preparation, printing, filing, delivery, and shipping of the Registration Statement (including the financial statements therein and all amendments, schedules, and exhibits thereto), the Securities, each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus and any amendment thereof or supplement thereto, and the printing, delivery, and shipping of this Agreement and other underwriting documents, including Blue Sky Memoranda (covering the states and other applicable jurisdictions), (C) all reasonable filing fees and reasonable fees and disbursements of the Underwriters’ counsel incurred in connection with the qualification of the Securities for offering and sale by the Underwriters or by dealers under the securities or blue sky laws of the states and other jurisdictions which you shall designate, (D) the reasonable fees and expenses of any transfer agent or registrar, (E) the reasonable filing fees and fees and disbursements of Underwriters’ counsel incident to any required review and approval by FINRA of the terms of the sale of the Securities, (F) listing fees, if any, (G) the cost and expenses of the Company relating to investor presentations or any “roadshow” undertaken in connection with marketing of the Securities, (H) all other costs and expenses of the Company incident to the performance of its obligations hereunder that are not otherwise specifically provided for herein and (I) all other reasonable costs and out-of-pocket expenses of the Underwriters (including reasonable fees and disbursements of counsel) incident to the performance of its obligations hereunder not otherwise specifically provided for here, provided however such costs and expenses provided for in this clause (C), (E) and (I) shall not exceed $150,000 in the aggregate, without the Company’s prior written consent. Notwithstanding the above, if this Agreement is terminated by the Representative pursuant to Section 9 hereof or if the sale of the Securities provided for herein is not consummated by reason of any failure, refusal or inability on the part of the Company to perform any agreement on its part to be performed, or because any other condition of the Underwriters’ obligations hereunder required to be fulfilled by the Company is not fulfilled, the Company will reimburse the several Underwriters for all out-of-pocket accountable disbursements (including but not limited to fees and disbursements of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges) incurred by the Underwriters in connection with their investigation, preparing to market and marketing the Securities or in contemplation of performing their obligations hereunder in an aggregate amount not to exceed $100,000 in the aggregate, without the Company’s prior written consent.

(viii) Use of Proceeds . The Company will apply the net proceeds from the sale of the Securities to be sold by it hereunder for the purposes set forth in the Time of Sale Disclosure Package and in the Prospectus.

(ix) Company Lock Up . The Company will not, without the prior written consent of Piper Jaffray & Co. , from the date of execution of this Agreement and continuing

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to and including the date 90 days after the date of the Prospectus (the “Lock-Up Period” ), (A) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or (B) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (A) or (B) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, except to the Underwriters pursuant to this Agreement. The restrictions contained in this Section 4(a)(ix) shall not apply to (i) the issuance by the Company of shares of Common Stock upon the exercise of a stock option or warrant or the conversion of a security outstanding on the date hereof, (ii) grants of options or the issuance of shares of Common Stock by the Company pursuant to equity incentive plans described in the Time of Sale Disclosure Package, (iii) the issuance of options or other equity awards to consultants of the Company in the ordinary course of business, and (iv) securities of the Company issued in connection with a joint venture or collaboration or other strategic or commercial relationship existing prior to, on or following the date hereof; provided, that in the case of clauses (iii) and (iv) any recipient (as applicable) agrees to be bound in writing by the restrictions set forth herein for the remainder of the Lock-Up Period and in the case of clause (iv), the aggregate amount of such issuances shall not exceed 5% of the total outstanding shares of Common Stock of the Company on the date hereof.

(x) Stockholder Lock-Ups . The Company has caused to be delivered to you prior to the date of this Agreement a letter, in the form of Exhibit A hereto (the “Lock-Up Agreement” ), from each individual or entity listed on Schedule IV. The Company will enforce the terms of each Lock-Up Agreement and issue stop-transfer instructions to the transfer agent for the Common Stock with respect to any transaction or contemplated transaction that would constitute a breach of or default under the applicable Lock-Up Agreement.

(xi) No Market Stabilization or Manipulation . The Company has not taken and will not take, directly or indirectly, any action designed to or which might reasonably be expected to cause or result in, or which has constituted, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities

(xii) SEC Reports . During the Prospectus Delivery Period, the Company will file on a timely basis with the Commission such periodic and special reports as required by the Rules and Regulations.

(xiii) Internal Controls . The Company will maintain such controls and other procedures, including without limitation those required by Sections 302 and 906 of the Sarbanes-Oxley Act and the applicable regulations thereunder, that are designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported

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within the time periods specified in the Commission’s rules and forms, including without limitation, controls and procedures designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the Company’s management, including its principal executive officer and its principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure, to ensure that material information relating to Company is made known to them by others within those entities.

(xiv) Sarbanes-Oxley . The Company will comply with all applicable provisions of the Sarbanes-Oxley Act.

(xv) Free Writing Prospectuses . The Company represents and agrees that, unless it obtains the prior written consent of Piper Jaffray & Co., and each Underwriter severally represents and agrees that, unless it obtains the prior written consent of the Company and Piper Jaffray & Co., it has not made and will not make any offer relating to the Securities that would constitute an issuer free writing prospectus or that would otherwise constitute a free writing prospectus required to be filed with the Commission; provided that the prior written consent of the parties hereto shall be deemed to have been given in respect of the free writing prospectuses included in Schedule II. Any such free writing prospectus consented to by the Company and Piper Jaffray & Co. is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated or agrees that it will treat each Permitted Free Writing Prospectus as an issuer free writing prospectus and has complied and will comply with the requirements of Rule 164 and Rule 433 applicable to any Permitted Free Writing Prospectus.

5. Conditions of Underwriters’ Obligations . The obligations of the several Underwriters hereunder are subject to the accuracy, as of the date hereof and the Closing Date (as if made at the Closing Date), of and compliance with all representations, warranties and agreements of the Company contained herein, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a) Required Filings; Absence of Certain Commission Actions . If filing of the Prospectus, or any amendment or supplement thereto, or any issuer free writing prospectus, is required under the Securities Act or the Rules and Regulations, the Company shall have filed the Prospectus (or such amendment or supplement) or such issuer free writing prospectus with the Commission in the manner and within the time period so required (without reliance on Rule 424(b)(8) or Rule 164(b)); the Registration Statement shall remain effective; no stop order suspending the effectiveness of the Registration Statement or any part thereof, any Rule 462(b) Registration Statement, or any amendment thereof, nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus shall have been issued; no proceedings for the issuance of such an order shall have been initiated or threatened; any request of the Commission for additional information (to be included in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, any issuer free writing prospectus or otherwise) shall have been complied with to your satisfaction.

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(b) Continued Compliance with Securities Laws . No Underwriter shall have advised the Company that (i) the Registration Statement or any amendment thereof or supplement thereto contains an untrue statement of a material fact which, in your opinion, is material or omits to state a material fact which, in your opinion, is required to be stated therein or necessary to make the statements therein not misleading, or (ii) the Time of Sale Disclosure Package or the Prospectus, or any amendment thereof or supplement thereto, or any issuer free writing prospectus contains an untrue statement of fact which, in your opinion, is material, or omits to state a fact which, in your opinion, is material and is required to be stated therein, or necessary to make the statements therein, in light of the circumstances under which they are made, not misleading.

(c) Absence of Certain Events . Except as contemplated in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, the Company shall not have incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there shall not have been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants or conversion of convertible securities), or any material change in the short-term or long-term debt of the Company (other than as a result of the conversion of convertible securities), or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock of the Company, or any Material Adverse Effect or any development involving a prospective Material Adverse Effect (whether or not arising in the ordinary course of business), or any loss by strike, fire, flood, earthquake, accident or other calamity, whether or not covered by insurance, incurred by the Company, the effect of which, in any such case described above, in your judgment, makes it impractical or inadvisable to offer or deliver the Securities on the terms and in the manner contemplated in the Time of Sale Disclosure Package and in the Prospectus.

(d) Opinion of Company Counsel . On each Closing Date, there shall have been furnished to you, as Representative of the several Underwriters, the opinion of Latham & Watkins LLP, counsel for the Company, dated the Closing Date and addressed to you in form and substance reasonably satisfactory to the Representative.

(e) Opinion of Underwriters’ Counsel . On each Closing Date, there shall have been furnished to you, as Representative of the several Underwriters, such opinion or opinions from Goodwin Procter LLP, counsel for the several Underwriters, dated the Closing Date and addressed to you, with respect to the formation of the Company, the validity of the Securities, the Registration Statement, the Time of Sale Disclosure Package, the Prospectus and other related matters as you reasonably may request, and such counsel shall have received such papers and information as they request to enable them to pass upon such matters.

(f) Comfort Letter . On the date hereof, on the effective date of any post-effective amendment to the Registration Statement filed after the date hereof and on each Closing Date you, as Representative of the several Underwriters, shall have received an accountant’s “comfort” letter of Ernst & Young LLP, dated such date and addressed to you, in form and substance satisfactory to you.

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(g) Officers’ Certificate . On each Closing Date, there shall have been furnished to you, as Representative of the Underwriters, a certificate, dated the Closing Date and addressed to you, signed by the chief executive officer and by the chief financial officer of the Company, to the effect that:

(i) The representations and warranties of the Company in this Agreement are true and correct as if made at and as of the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date;

(ii) No stop order or other order suspending the effectiveness of the Registration Statement or any part thereof or any amendment thereof or the qualification of the Securities for offering or sale or notice that would prevent use of the Registration Statement, nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus, has been issued, and no proceeding for that purpose has been instituted or, to the best of their knowledge, is contemplated by the Commission or any state or regulatory body; and

(iii) Affirms the accuracy of the matters set forth in subsection (C) of this Section 5.

(h) Lock-Up Agreement . The Underwriters shall have received all of the Lock-Up Agreements referenced in Section 4 and the Lock-Up Agreements shall remain in full force and effect.

(i) FINRA No Objections . FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(j) Other Documents . The Company shall have furnished to you and counsel for the Underwriters such additional documents, certificates and evidence as you or they may have reasonably requested.

(k) Exchange Listing . The Shares (and the Warrant Shares underlying the Warrants) to be delivered on the Closing Date will be listed on Nasdaq.

(l) Warrant Agreements . The Underwriters shall have received copies of the Warrant Agreement, duly executed by the Company and the Warrant Agent.

(m) Transfer Agent . The Company will maintain a transfer agent and maintain a warrant agent for the Warrants.

(n) Warrant Share Reserve. The Company shall, at all times while any Warrants are outstanding, reserve and keep available out of the aggregate of its authorized but unissued

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and otherwise unreserved shares of Common Stock, solely for the purpose of enabling it to issue Warrant Shares upon exercise of such Warrants, the number of Warrant Shares that are issuable and deliverable upon the exercise of the then-outstanding Warrants from time to time.

All such opinions, certificates, letters and other documents will be in compliance with the provisions hereof only if they are satisfactory in form and substance to you and counsel for the Underwriters. The Company will furnish you with such conformed copies of such opinions, certificates, letters and other documents as you shall reasonably request.

6. Indemnification and Contribution .

(a) Indemnification by the Company . The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any losses, claims, damages or liabilities, joint or several, to which such Underwriter may become subject, under the Act or otherwise (including in settlement of any litigation if such settlement is effected with the written consent of the Company), insofar as such losses, claims, damages or liabilities (or actions in respect thereof) directly arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, including the 430A or 430B Information and any other information deemed to be a part of the Registration Statement at the time of effectiveness and at any subsequent time pursuant to the Rules and Regulations, if applicable, any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, or any amendment or supplement thereto, any issuer free writing prospectus, or any issuer information that the Company has filed or is required to file pursuant to Rule 433(d) of the Rules and Regulations, or directly arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in light of (other than in the case of the Registration Statement) the circumstances under which they are made, not misleading, and will reimburse each Underwriter for any legal or other expenses reasonably incurred by it in connection with investigating or defending against such loss, claim, damage, liability or action as such expenses are incurred; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in reliance upon and in conformity with written information furnished to the Company by you, or by any Underwriter through you, specifically for use in the preparation thereof; it being understood and agreed that the only information furnished by an Underwriter consists of the information described as such in Section 6(e).

(b) Indemnification by the Underwriters . Each Underwriter will, severally and not jointly, indemnify and hold harmless the Company, its affiliates, directors and officers and each person, if any, who controls the Company within the meaning of Section 15 of the Act and Section 20 of the Exchange Act, from and against any losses, claims, damages or liabilities to which the Company may become subject, under the Act or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of such Underwriter), insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, or any

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amendment or supplement thereto, or any issuer free writing prospectus, or any issuer information that the Company has filed or is required to file pursuant to Rule 433(d) of the Rules and Regulations, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in light of (other than in the case of the Registration Statement) the circumstances under which they are made, not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by you, or by such Underwriter through you, specifically for use in the preparation thereof (it being understood and agreed that the only information furnished by an Underwriter consists of the information described as such in Section 6(e)), and will reimburse the Company for any legal or other expenses reasonably incurred by the Company in connection with investigating or defending against any such loss, claim, damage, liability or action as such expenses are incurred.

(c) Notice and Procedures . Promptly after receipt by an indemnified party under subsection (a) or (b) above of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under such subsection, notify the indemnifying party in writing of the commencement thereof; but the omission so to notify the indemnifying party shall not relieve the indemnifying party from any liability that it may have to any indemnified party except to the extent such indemnifying party has been materially prejudiced by such failure (through the forfeiture of substantive rights or defenses). In case any such action shall be brought against any indemnified party, and it shall notify the indemnifying party of the commencement thereof, the indemnifying party shall be entitled to participate in, and, to the extent that it shall wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party, and after notice from the indemnifying party to such indemnified party of the indemnifying party’s election so to assume the defense thereof, the indemnifying party shall not be liable to such indemnified party under such subsection for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided , however , that if, in the sole judgment of the indemnified party, it is advisable for the indemnified party to be represented as a group by separate counsel, the indemnified party shall have the right to employ a single counsel (in addition to local counsel) to represent the indemnified parties who may be subject to liability arising from any claim in respect of which indemnity may be sought by the Underwriters under subsection (a) of this Section 6, in which event the reasonable fees and expenses of such separate counsel shall be borne by the indemnifying party or parties and reimbursed to the Underwriters as incurred. An indemnifying party shall not be obligated under any settlement agreement relating to any action under this Section 6 to which it has not agreed in writing. In addition, no indemnifying party shall, without the prior written consent of the indemnified party (which consent shall not be unreasonably withheld or delayed), effect any settlement of any pending or threatened proceeding unless such settlement includes an unconditional release of such indemnified party for all liability on claims that are the subject matter of such proceeding and does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party. Notwithstanding the foregoing, if at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel pursuant to this Section 6(c), such indemnifying party agrees that it shall be liable for any settlement effected without its written consent if (i) such settlement is entered into more than 45 days

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after receipt by such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed such indemnified party in accordance with such request prior to the date of such settlement.

(d) Contribution; Limitations on Liability; Non-Exclusive Remedy . If the indemnification provided for in this Section 6 is unavailable or insufficient to hold harmless an indemnified party under subsection (a) or (b) above, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of the losses, claims, damages or liabilities referred to in subsection (a) or (b) above, (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other from the offering of the Securities or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand and the Underwriters on the other in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions received by the Underwriters, in each case as set forth in the table on the cover page of the Prospectus. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or the Underwriters and the parties’ relevant intent, knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The Company and the Underwriters agree that it would not be just and equitable if contributions pursuant to this subsection (d) were to be determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to in the first sentence of this subsection (d). The amount paid by an indemnified party as a result of the losses, claims, damages or liabilities referred to in the first sentence of this subsection (d) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending against any action or claim which is the subject of this subsection (d). Notwithstanding the provisions of this subsection (d), no Underwriter shall be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the Securities purchased by it hereunder exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (d) to contribute are several in proportion to their respective underwriting obligations and not joint. The remedies provided for in this Section 6 are not exclusive and shall not limit any rights or remedies that might otherwise be available to any indemnified party at law or in equity.

(e) Information Provided by the Underwriters . The Underwriters severally confirm and the Company acknowledges that the statements with respect to the public offering of the Securities by the Underwriters set forth in second, eleventh and twelfth paragraphs under the

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caption “Underwriting” in the Time of Sale Disclosure Package and in the Prospectus are correct and constitute the only information concerning such Underwriters furnished in writing to the Company by or on behalf of the Underwriters specifically for inclusion in the Registration Statement, any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus or any issuer free writing prospectus.

7. Representations and Agreements to Survive Delivery . All representations, warranties, and agreements of the Company herein or in certificates delivered pursuant hereto, including but not limited to the agreements of the several Underwriters, the Company contained in Section 6 hereof, shall remain operative and in full force and effect regardless of any investigation made by or on behalf of any Underwriter or any controlling person thereof, or the Company or any of its officers, directors, or controlling persons, and shall survive delivery of, and payment for, the Securities to and by the Underwriters hereunder and any termination of this Agreement.

8. Substitution of Underwriters .

(a) Obligation to Purchase Under Certain Circumstances . If any Underwriter or Underwriters shall fail to take up and pay for the amount of Securities agreed by such Underwriter or Underwriters to be purchased hereunder, upon tender of such Securities in accordance with the terms hereof, and the amount of Securities not purchased does not aggregate more than 10% of the total amount of Securities set forth in Schedule I hereto, the remaining Underwriters shall be obligated to take up and pay for (in proportion to their respective underwriting obligations hereunder as set forth in Schedule I hereto except as may otherwise be determined by you) the Securities that the withdrawing or defaulting Underwriters agreed but failed to purchase.

(b) Termination Under Certain Circumstances . If any Underwriter or Underwriters shall fail to take up and pay for the amount of Securities agreed by such Underwriter or Underwriters to be purchased hereunder, upon tender of such Securities in accordance with the terms hereof, and the amount of Securities not purchased aggregates more than 10% of the total amount of Securities set forth in Schedule I hereto, and arrangements satisfactory to you for the purchase of such Securities by other persons are not made within 36 hours thereafter, this Agreement shall terminate. In the event of any such termination the Company shall not be under any liability to any Underwriter (except to the extent provided in Section 4(a)(vii) and Section 6 hereof) nor shall any Underwriter (other than an Underwriter who shall have failed, otherwise than for some reason permitted under this Agreement, to purchase the amount of Securities agreed by such Underwriter to be purchased hereunder) be under any liability to the Company (except to the extent provided in Section 6 hereof).

(c) Postponement of Closing . If Securities to which a default relates are to be purchased by the non-defaulting Underwriters or by any other party or parties, the Representative or the Company shall have the right to postpone the Closing Date for not more than seven business days in order that the necessary changes in the Registration Statement, in the Time of Sale Disclosure Package, in the Prospectus or in any other documents, as well as any other arrangements, may be effected. As used herein, the term “Underwriter” includes any person substituted for an Underwriter under this Section 8.

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(d) No Relief from Liability . No action taken pursuant to this Section shall relieve any defaulting Underwriter from liability, if any, in respect of such default.

9. Termination of this Agreement .

(a) Right to Terminate . You, as Representative of the several Underwriters, shall have the right to terminate this Agreement by giving notice to the Company as hereinafter specified at any time at or prior to the Closing Date, if (i) the Company or shall have failed, refused or been unable, at or prior to the Closing Date, to perform any agreement on its or their part to be performed hereunder, (ii) any condition of the Underwriters’ obligations hereunder is not fulfilled, (iii) trading in the Company’s Common Stock shall have been suspended by the Commission or The NASDAQ Stock Market or trading in securities generally on the NASDAQ Stock Market or New York Stock Exchange shall have been suspended, (iv) minimum or maximum prices for trading shall have been fixed, or maximum ranges for prices for securities shall have been required, on the NASDAQ Stock Market or New York Stock Exchange, by such Exchange or by order of the Commission or any other Governmental Authority, (v) a banking moratorium shall have been declared by federal or New York state authorities or a material disruption in commercial banking or securities settlement or clearance services in the United States, or (vi) there shall have occurred any attack on, outbreak or escalation of hostilities or act of terrorism involving the United States, any declaration by the United States of a national emergency or war, any change in financial markets or any other calamity or crisis that, in your judgment, is material and adverse and makes it impractical or inadvisable to proceed with the completion of the sale of and payment for the Securities. Any such termination shall be without liability of any party to any other party except that the provisions of Section 4(a)(vii) and Section 6 hereof shall at all times be effective and shall survive such termination.

(b) Notice of Termination . If you elect to terminate this Agreement as provided in this Section, the Company shall be notified promptly by you by telephone, confirmed by letter.

10. Default by the Company .

(a) Default by the Company . If the Company shall fail at the Closing Date to sell and deliver the number of Securities which it is obligated to sell hereunder, then this Agreement shall terminate without any liability on the part of any Underwriter or, except as provided in Section 4(a)(vii) and Section 6 hereof, any non-defaulting party.

(b) No Relief from Liability . No action taken pursuant to this Section shall relieve the Company from liability, if any, in respect of such default.

11. Notices . Except as otherwise provided herein, all communications hereunder shall be in writing and, if to the Underwriters, shall be mailed via overnight delivery service or hand delivered via courier to the Representative c/o Piper Jaffray & Co., U.S. Bancorp Center, 800 Nicollet Mall, Minneapolis, Minnesota 55402, Attention: Equity Capital Markets, with a copy to General Counsel; if to the Company, shall be mailed or delivered to it at 28 Wells Avenue, Third Floor,

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Yonkers, New York 10701, Attention: General Counsel. Any party to this Agreement may change such address for notices by sending to the parties to this Agreement written notice of a new address for such purpose.

12. Persons Entitled to Benefit of Agreement . This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and assigns and the controlling persons, officers and directors referred to in Section 6. Nothing in this Agreement is intended or shall be construed to give to any other person, firm or corporation any legal or equitable remedy or claim under or in respect of this Agreement or any provision herein contained. The term “successors and assigns” as herein used shall not include any purchaser, as such purchaser, of any of the Securities from any of the several Underwriters.

13. Absence of Fiduciary Relationship . The Company acknowledges and agrees that: (a) the Representative have been retained solely to act as an underwriter in connection with the sale of the Securities and that no fiduciary, advisory or agency relationship between the Company and the Representative have been created in respect of any of the transactions contemplated by this Agreement, irrespective of whether the Representative has advised or is advising the Company or on other matters; (b) the price and other terms of the Securities set forth in this Agreement were established by the Company following discussions and arms-length negotiations with the Representative and the Company is capable of evaluating and understanding and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement; (c) it has been advised that the Representative and its affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that the Representative has no obligation to disclose such interest and transactions to the Company by virtue of any fiduciary, advisory or agency relationship; (d) it has been advised that the Representative is acting, in respect of the transactions contemplated by this Agreement, solely for the benefit of the Representative and the other Underwriters, and not on behalf of the Company; (e) it waives to the fullest extent permitted by law, any claims it may have against the Representative for breach of fiduciary duty or alleged breach of fiduciary duty in respect of any of the transactions contemplated by this Agreement and agrees that the Representative shall have no liability (whether direct or indirect) to the Company in respect of such a fiduciary duty claim on behalf of or in right of the Company, including stockholders, employees or creditors of the Company.

14. Governing Law; Waiver of Jury Trial . This Agreement shall be governed by and construed in accordance with the laws of the State of New York. The Company (on its behalf and, to the extent permitted by applicable law, on behalf of its stockholders and affiliates) and each of the Underwriters hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

15. Counterparts . This Agreement may be executed in one or more counterparts and, if executed in more than one counterpart, the executed counterparts shall each be deemed to be an original and all such counterparts shall together constitute one and the same instrument.

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16. General Provisions. This Agreement constitutes the entire agreement of the parties to this Agreement and supersedes all prior written or oral and all contemporaneous oral agreements, understandings and negotiations with respect to the subject matter hereof. This Agreement may not be amended or modified unless in writing by all of the parties hereto, and no condition herein (express or implied) may be waived unless waived in writing by each party whom the condition is meant to benefit. The Section headings herein are for the convenience of the parties only and shall not affect the construction or interpretation of this Agreement. The invalidity or unenforceability of any Section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other Section, paragraph or provision hereof. If any Section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

[Signature Page Follows]

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Please sign and return to the Company the enclosed duplicates of this letter whereupon this letter will become a binding agreement between the Company and the several Underwriters in accordance with its terms.

SCHEDULE II

Certain Permitted Free Writing Prospectuses

Issuer Free Writing Prospectus dated July 21, 2016

Issuer Free Writing Prospectus dated July 22, 2016

SCHEDULE III

Pricing Information

Number of Shares Being Offered: 14,000,000

Number of Accompanying Warrants: 14,000,000

Offering Price Per Share and Accompanying Warrant: $2.50

Exercise Price Per Warrant: $3.00

Underwriting Discounts and Commissions: 6.50%

SCHEDULE IV

List of Individuals and Entities Executing Lock-Up Agreements

Directors

Steven C. Gilman, Ph.D. (Chairman and CEO)

Sol Barer, Ph.D.

Isaac Blech

David N. Low, Jr.

Michael J. Otto, Ph.D.

Roger J Pomerantz, M.D., F.A.C.P.

Cary W. Sucoff

Officers

Natalie Bogdanos

Cara Cassino, M.D.

Nancy Dong

Michael Messinger

Josh Munter

Michael Wittekind, Ph.D.

EXHIBIT A

[FORM OF WARRANT AGREEMENT]

WARRANT AGREEMENT

This Warrant Agreement (“ Warrant Agreement ”) is entered into as of July 27, 2016, by and between ContraFect Corporation, a Delaware corporation (the “ Company ”), and American Stock Transfer & Trust Company, LLC (the “ Warrant Agent ”).

WHEREAS, the Company is engaged in a public offering (the “ Public Offering ”) of shares of common stock of the Company, par value $0.0001 per share (the “ Common Stock ”), and warrants (each a “ Warrant ” or, collectively, the “ Warrants ”) entitling holders to purchase shares of Common Stock (the “ Warrant Shares ” ) ;

WHEREAS, the shares of Common Stock and the Warrants will be sold in combination, with one warrant to purchase one (1) share of Common Stock accompanying each share of Common Stock sold. The shares of Common Stock and the Warrants are immediately separable and will be issued separately;

WHEREAS, the Company has filed, with the Securities and Exchange Commission, a registration statement on Form S-3 (Registration No. 333-211748), as amended (the “ Registration Statement ”), for the registration, under the Securities Act of 1933, as amended (the “ Act ”), of, among other securities, the Warrants and the Warrant Shares;

WHEREAS, the Company desires the Warrant Agent to act on behalf of the Company, and the Warrant Agent is willing to so act, in connection with the issuance, registration, transfer, exchange and exercise of the Warrants;

WHEREAS, the Company desires to provide for the form, terms and provisions of the Warrants, including the terms upon which they shall be issued and exercised, and the respective rights, limitation of rights and immunities of the Company, the Warrant Agent and the holders of the Warrants; and

WHEREAS, all acts and things have been done and performed which are necessary to make the Warrants, when executed on behalf of the Company and countersigned by or on behalf of the Warrant Agent, as provided herein, the legally valid and binding obligations of the Company, and to authorize the execution and delivery of this Warrant Agreement.

NOW, THEREFORE, in consideration of the mutual agreements herein contained, the parties hereto agree as follows:

1. Appointment of Warrant Agent . The Company hereby appoints the Warrant Agent to act as agent for the Company for the Warrants, and the Warrant Agent hereby accepts such appointment and agrees to perform the same in accordance with the terms and conditions set forth in this Warrant Agreement.

2. Warrants .

2.1 Book-Entry Warrant Certificates . The Warrants shall initially be issuable in book-entry registration only and evidenced by a global Warrant Certificate (the “ Book-Entry Warrant Certificates ”). All of the Warrants shall initially be represented by one or more Book-Entry Warrant Certificates deposited with the Depository Trust Company (“ Depository ”) and registered in the name of Cede & Co., as nominee of the Depository. Ownership of beneficial interests in the Warrants shall be shown on, and the transfer of such ownership shall be effected through, records maintained by (i) the Depository or its nominee for each Book-Entry Warrant Certificate or (ii) institutions that have accounts with the Depository (such institutions, with respect to a Warrant in its account, each a “ Participant ”). If the Depository subsequently ceases to make its book-entry settlement system available for the Warrants, the Company may instruct the Warrant Agent regarding other arrangements for book-entry settlement. In the event that the Warrants are not eligible for, or it is no longer necessary to have the Warrants available in, book-entry form, the Warrant Agent shall provide written instructions to the Depository to deliver to the Warrant Agent for cancellation each Book-Entry Warrant Certificate, and the Company shall instruct the Warrant Agent to deliver to each Holder a warrant certificate in substantially the form of Exhibit A hereto, the provisions of which are incorporated herein and signed by, or bear the facsimile signature of, an authorized signatory. In the event the person whose facsimile signature has been placed upon any Warrant shall have ceased to serve in the capacity in which such person signed the Warrant before such Warrant is issued, it may be issued with the same effect as if he or she had not ceased to be such at the date of issuance.

2.2 Effect of Countersignature . Unless and until countersigned by the Warrant Agent pursuant to this Warrant Agreement, a Warrant shall be invalid and of no effect and may not be exercised by the holder thereof.

2.3 Registration .

2.3.1 Warrant Register . The Warrant Agent shall maintain a register (the “ Warrant Register ”), for the registration of the original issuance and transfers of the Warrants. Upon the initial issuance of the Warrants, the Warrant Agent shall issue and register the Warrants in the names of the respective holders thereof in such denominations and otherwise in accordance with instructions delivered to the Warrant Agent by the Company.

2.3.2 Registered Holder . Prior to due presentment for registration of transfer of any Warrant, the Company and the Warrant Agent may deem and treat the person in whose name such Warrant shall be registered upon the Warrant Register (“ Registered Holder ”) as the absolute owner of such Warrant and of each Warrant represented thereby (notwithstanding any notation of ownership or other writing on the Warrant certificate made by anyone other than the Company or the Warrant Agent), for the purpose of any exercise thereof, and for all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.

3. Terms and Exercise of Warrants .

3.1 Warrant Price . Each Warrant shall, when countersigned by the Warrant Agent, entitle the Registered Holder thereof, subject to the provisions of such Warrant and of this Warrant Agreement, to purchase from the Company the number of shares of Common Stock

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stated therein, at the price of $3.00 per share of Common Stock, subject to the adjustments provided in Section 4 hereof. The term “ Warrant Price ” as used in this Warrant Agreement refers to the price per whole share at which Common Stock may be purchased at the time such Warrant is exercised.

3.2 Duration of Warrants . A Warrant may be exercised only during the period (“ Exercise Period ”) commencing on the date of original issuance and terminating at 5:00 p.m., New York City time, on July 27, 2021 (sixty (60) months following the closing date of the Public Offering) (“ Expiration Date ”). Each Warrant not exercised on or before the Expiration Date shall become void, and all rights thereunder and all rights in respect thereof under this Warrant Agreement shall cease at the close of business on the Expiration Date. The Company may extend the duration of the Warrants by delaying the Expiration Date; provided, however, that the Company will provide notice of not less than 20 days to Registered Holders of such extension and that such extension shall be identical in duration among all of the then outstanding Warrants.

3.3 Exercise of Warrants .

3.3.1 Payment . Subject to the provisions of the Warrant and this Warrant Agreement, a Warrant, when countersigned by the Company, may be exercised by the Registered Holder thereof by surrendering it at the office of the Warrant Agent (or, in the case of a global Book-Entry Certificate, properly delivered by the Participant in accordance with the Depository’s procedures), or at the office of its successor as Warrant Agent, currently being:

American Stock Transfer & Trust Company, LLC

6201 15th Avenue

Brooklyn, New York 11219

2nd floor—Reorganization Department

with the subscription form, as set forth in the Warrant, duly executed, and by paying in full, in lawful money of the United States (or pursuant to the cashless exercise procedure specified in Section 3.3.3 below, if such cashless exercise procedure is applicable), by certified or bank cashier’s check payable to the order of the Warrant Agent or by wire transfer to the Warrant Agent’s bank account designated by it, the Warrant Price for each whole Warrant Share as to which the Warrant is exercised and any and all applicable taxes due in connection with the exercise of the Warrant, the exchange of the Warrant for the Warrant Shares, and the issuance of the Warrant Shares.

3.3.2 Fractional Shares . Notwithstanding any provision to the contrary contained in this Warrant Agreement, the Company shall not be required to issue any fraction of a Warrant Share in connection with the exercise of Warrants, and in any case where the Registered Holder would be entitled under the terms of the Warrants to receive a fraction of a Warrant Share upon the exercise of such Registered Holder’s Warrants, issue or cause to be issued only the largest whole number of Warrant Shares issuable on such exercise (and such fraction of a Warrant Share will be disregarded); provided, that if more than one Warrant certificate is presented for exercise at the same time by the same Registered Holder, the number of whole Warrant Shares which shall be issuable upon the exercise thereof shall be computed on the basis of the aggregate number of Warrant Shares issuable on exercise of all such Warrants.

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3.3.3 Cashless Exercise . If an effective registration statement is available for the issuance of the Warrant Shares (as determined by the Company in its sole discretion), then the Warrants may only be exercised, in whole or in part, at such time by means of a cash exercise specified in Section 3.3.1. If at the time of exercise hereof there is no effective registration statement registering, or the prospectus contained therein is not available for the issuance of the Warrant Shares to the Registered Holders (as determined by the Company in its sole discretion), then the Warrants may only be exercised, in whole or in part, at such time by means of a “cashless exercise” in which the Registered Holders shall be entitled to receive that number of Warrant Shares equal to the quotient obtained by dividing (A-B) (X) by (A), where:

(A) = the per share volume-weighted average price as displayed under the heading ‘‘Bloomberg VWAP’’ on Bloomberg page ‘‘CFRX <equity> AQR’’ (or its equivalent successor if such page is not available) in respect of the period from the scheduled open of trading until the scheduled close of trading of the primary trading session on the VWAP Trading Day (as defined below) immediately preceding the date on which a Registered Holder elects to exercise the Warrant and “cashless exercise” applies (or if such volume weighted average price is unavailable, the market value of one share of Common Stock on such VWAP Trading Day determined, using a volume-weighted average method, by a nationally recognized independent investment banking firm retained for this purpose by the Company; the volume-weighted average price will be determined without regard to after-hours trading or any other trading outside of the regular trading session trading hours);

(B) = the then applicable Warrant Price of the Warrant; and

(X) = the number of Warrant Shares that would be issuable upon exercise of such Warrant in accordance with the terms of the Warrant if such exercise were by means of a cash exercise rather than a cashless exercise.

As used herein, “ VWAP Trading Day ” means a day on which (i) there is no VWAP Market Disruption Event (as defined below) and (ii) trading in the Common Stock generally occurs on the Nasdaq Capital Market or, if the Common Stock is not then listed on the Nasdaq Capital Market, on the other principal U.S. national or regional securities exchange on which the Common Stock is then listed or, if the Common Stock is not then listed on a U.S. national or regional securities exchange, on the principal other market on which the Common Stock is then traded. If the Common Stock (or any other security for which a daily volume-weighted average price must be determined) is not so listed or traded, “ VWAP Trading Day ” means a “business day.” “ VWAP Market Disruption Event ” means (i) a failure by the principal U.S. national or regional securities exchange or market on which the Common Stock is listed or admitted for trading to open for trading during its regular trading session or (ii) on any scheduled VWAP Trading Day for the Common Stock, the occurrence or existence prior to 1:00 p.m., New York City time, for more than a one half-hour period in the aggregate during regular trading hours, of any suspension or limitation imposed on trading (by reason of movements in price exceeding limits permitted by the relevant stock exchange or otherwise) in the Common Stock or in any

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options, contracts or futures contracts relating to the Common Stock. The Company will be responsible for determining whether cashless exercise applies to a Warrant exercise and will notify the Warrant Agent if it does. The Company shall calculate and transmit to the Warrant Agent, and the Warrant Agent shall have no obligation under this section to calculate, the number of Warrant Shares issuable in connection with the cashless exercise. The Warrant Agent will promptly return the Warrant Price paid by the Registered Holder in the event a cashless exercise applies.

3.3.4 Issuance of Certificates . No later than three (3) business days following the exercise of any Warrant and the clearance of the funds in payment of the Warrant Price, the Company shall issue to the Registered Holder of such Warrant a certificate or certificates representing (or deliver electronically through the facilities of the Depository Trust Corporation) the number of full shares of Common Stock to which he, she or it is entitled, registered in such name or names as may be directed by him, her or it, and, if such Warrant shall not have been exercised or surrendered in full (provided that the holder has delivered the original physical Warrant Certificate to the Warrant Agent, which delivery shall not include delivery of a notice from the Depository of the transfer or exercise of Warrants in the form of a global Book-Entry Warrant Certificate), a new countersigned Warrant for the number of shares as to which such Warrant shall not have been exercised or surrendered. If fewer than all the Warrants evidenced by a global Book-Entry Warrant Certificate are exercised, a notation shall be made to the records maintained by the Depository, its nominee for each global Book-Entry Warrant Certificate, or a Participant, as appropriate, evidencing the balance of the Warrants remaining after such exercise. Warrants may not be exercised by, or securities issued to, any Registered Holder in any state in which such exercise or issuance would be unlawful. In the event such exercise would be unlawful with respect to a Registered Holder in any state, the Registered Holder shall not be entitled to exercise such Warrants and such Warrants may have no value and expire worthless.

3.3.5 Valid Issuance . All shares of Common Stock issued upon the proper exercise or surrender of a Warrant in conformity with this Warrant Agreement shall be validly issued, fully paid and non-assessable.

3.3.6 Date of Issuance . Each person or entity in whose name any such certificate for shares of Common Stock is issued shall, for all purposes, be deemed to have become the holder of record of such shares on the date on which the Warrant was surrendered and payment of the Warrant Price was made, irrespective of the date of delivery of such certificate, except that, if the date of such surrender and payment is a date when the stock transfer books of the Company 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.

3.3.7 Holder’s Exercise Limitations . The Company shall not effect any exercise of a Warrant, and a holder shall not have the right to exercise any portion of a Warrant to the extent that after giving effect to such issuance after exercise, the holder (together with the holder’s affiliates, and any other persons acting as a group together with the holder or any of the holder’s affiliates), would beneficially own in excess of the Beneficial Ownership Limitation (as defined below). For purposes of the foregoing sentence, the number of shares of Common Stock beneficially owned by the holder and its affiliates shall include the number of shares of Common Stock issuable upon exercise of a Warrant with respect to which such determination is being

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made, but shall exclude the number of shares of Common Stock which would be issuable upon (i) exercise of the remaining, nonexercised portion of a Warrant beneficially owned by the holder or any of its affiliates and (ii) exercise or conversion of the unexercised or nonconverted portion of any other securities of the Company subject to a limitation on conversion or exercise analogous to the limitation contained herein beneficially owned by the holder or any of its affiliates. Except as set forth in the preceding sentence, for purposes of this Section 3.3.7, beneficial ownership shall be calculated in accordance with Section 13(d) of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”) and the rules and regulations promulgated thereunder, it being acknowledged by the holder that the Company is not representing to the holder that such calculation is in compliance with Section 13(d) of the Exchange Act and the holder is solely responsible for any schedules required to be filed in accordance therewith. To the extent that the limitation contained in this Section 3.3.7 applies, the determination of whether a Warrant is exercisable (in relation to other securities owned by the holder together with any affiliates) and of which portion of a Warrant is exercisable shall be in the sole discretion of the holder, and the submission of a subscription form shall be deemed to be the holder’s determination of whether a Warrant is exercisable (in relation to other securities owned by the holder together with any affiliates) and of which portion of a Warrant is exercisable, in each case subject to the Beneficial Ownership Limitation, and the Company shall have no obligation to verify or confirm the accuracy of such determination. In addition, a determination as to any group status as contemplated above shall be determined in accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. For purposes of this Section 3.3.7, in determining the number of outstanding shares of Common Stock, a holder may rely on the number of outstanding shares of Common Stock as reflected in (A) the Company’s most recent periodic or annual report filed with the Securities and Exchange Commission, as the case may be, (B) a more recent public announcement by the Company or (C) a more recent written notice by the Company or its transfer agent setting forth the number of shares of Common Stock outstanding. Upon the written or oral request of a holder, the Company shall within two Trading Days (as defined below) confirm orally and in writing to the holder the number of shares of Common Stock then outstanding. In any case, the number of outstanding shares of Common Stock shall be determined after giving effect to the conversion or exercise of securities of the Company, including a Warrants, by the holder or its affiliates since the date as of which such number of outstanding shares of Common Stock was reported. The “ Beneficial Ownership Limitation ” shall be 9.99% of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common Stock issuable upon exercise of the Warrant. The Holder, upon not less than 61 days’ prior notice to the Company, may waive the Beneficial Ownership Limitation provisions of this Section 3.3.7. Any such waiver will not be effective until the 61st day after such notice is delivered to the Company. The provisions of this paragraph shall be construed and implemented in a manner otherwise than in strict conformity with the terms of this Section 3.3.7 to correct this paragraph (or any portion hereof) which may be defective or inconsistent with the intended Beneficial Ownership Limitation herein contained or to make changes or supplements necessary or desirable to properly give effect to such limitation. The limitations contained in this paragraph shall apply to a successor holder of a Warrant.

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4. Adjustments .

4.1 Stock Dividends, Splits . If, after the date hereof, and subject to the provisions of Section 4.5 below, the number of outstanding shares of Common Stock is increased by a stock dividend payable in shares of Common Stock, or by a forward or reverse split of shares of Common Stock, or other similar event, then, on the effective date of such stock dividend, split or similar event, the number of shares of Common Stock issuable on exercise of each Warrant shall be increased or decreased in proportion to such increase or decrease in outstanding shares of Common Stock.

4.2 Aggregation of Shares . If, after the date hereof, and subject to the provisions of Section 4.6, the number of outstanding shares of Common Stock is decreased by a consolidation, combination or reclassification of shares of Common Stock or other similar event, then, on the effective date of such consolidation, combination, reclassification or similar event, the number of shares of Common Stock issuable on exercise of each Warrant shall be decreased in proportion to such decrease in outstanding shares of Common Stock.

4.3 Adjustments in Exercise Price . Whenever the number of shares of Common Stock purchasable upon the exercise of the Warrants is adjusted, as provided in Sections 4.1 and 4.2 above, the Warrant Price shall be adjusted (to the nearest cent) by multiplying such Warrant Price, immediately prior to such adjustment, by a fraction, (a) the numerator of which shall be the number of shares of Common Stock purchasable upon the exercise of the Warrants immediately prior to such adjustment, and (b) the denominator of which shall be the number of shares of Common Stock so purchasable immediately thereafter.

4.4 Fundamental Transaction . If, at any time while this Warrant is outstanding, (i) the Company, directly or indirectly, in one or more related transactions effects any merger or consolidation of the Company with or into another Person, (ii) the Company, directly or indirectly, effects any sale, lease, license, assignment, transfer, conveyance or other disposition of all or substantially all of its assets in one or a series of related transactions, (iii) any, direct or indirect, purchase offer, tender offer or exchange offer (whether by the Company or another Person) is completed pursuant to which holders of Common Stock are permitted to sell, tender or exchange their shares for other securities, cash or property and has been accepted by the holders of 50% or more of the outstanding Common Stock, (iv) the Company, directly or indirectly, in one or more related transactions effects any reclassification, reorganization or recapitalization of the Common Stock or any compulsory share exchange pursuant to which the Common Stock is effectively converted into or exchanged for other securities, cash or property, or (v) the Company, directly or indirectly, in one or more related transactions consummates a stock or share purchase agreement or other business combination (including, without limitation, a reorganization, recapitalization, spin-off or scheme of arrangement) with another Person or group of Persons whereby such other Person or group acquires more than 50% of the outstanding shares of Common Stock (not including any shares of Common Stock held by the other Person or other Persons making or party to, or associated or affiliated with the other Persons making or party to, such stock or share purchase agreement or other business combination) (each a “Fundamental Transaction”), then, upon any subsequent exercise of the Warrant, the holder of this Warrant shall have the right to receive, for each Warrant Share that would have been issuable upon such exercise immediately prior to the occurrence of such Fundamental Transaction (without regard to any limitation in Section 3.3.7 on the exercise of this Warrant), the number of shares of Common Stock of the Company, if it is the surviving corporation, and

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any additional consideration (including any shares in any successor corporation or other entity acquiring the Company) (the “ Alternate Consideration ”) receivable as a result of such Fundamental Transaction by a holder of a share of Common Stock for which this Warrant is exercisable immediately prior to such Fundamental Transaction (without regard to any limitation in Section 3.3.7 on the exercise of this Warrant). For purposes of any such exercise, the determination of the Warrant Price shall be appropriately adjusted to apply to such Alternate Consideration based on the amount of Alternate Consideration issuable in respect of one share of common stock in such Fundamental Transaction, and the Company shall apportion the exercise price among the Alternate Consideration in a reasonable manner reflecting the relative value of any different components of the Alternate Consideration. If holders of Common Stock are given any choice as to the securities, cash or property to be received in a Fundamental Transaction, then the holder of the Warrant shall be given the same choice as to the Alternate Consideration it receives upon any exercise of this Warrant following such Fundamental Transaction. Notwithstanding anything to the contrary, in the event of a Fundamental Transaction that is (1) an all cash transaction, (2) a “Rule 13e-3 transaction” as defined in Rule 13e-3 under the Exchange Act, or (3) a Fundamental Transaction involving a person or entity not traded on a national securities exchange, including, but not limited to, the NYSE MKT, the Nasdaq Global Select Market, the Nasdaq Global Market, or the Nasdaq Capital Market, the Company or any Successor Entity (as defined below) shall, at the option of the holder of this Warrant, exercisable at any time concurrently with, or within 30 days after, the consummation of the Fundamental Transaction, purchase this Warrant from the holder by paying to the holder an amount of cash equal to the Black Scholes Value of the remaining unexercised portion of this Warrant on the date of the consummation of such Fundamental Transaction. “ Black Scholes Value ” means the value of this Warrant based on the Black and Scholes Option Pricing Model obtained from the “OV” function on Bloomberg determined as of the day of consummation of the applicable Fundamental Transaction for pricing purposes and reflecting (A) a risk-free interest rate corresponding to the U.S. Treasury rate for a period equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Expiration Date, (B) an expected volatility equal to the greater of 100% and the 100 day volatility obtained from the HVT function on Bloomberg as of the trading day immediately following the public announcement of the applicable Fundamental Transaction, (C) the underlying price per share used in such calculation shall be the sum of the price per share being offered in cash, if any, plus the value of any non-cash consideration, if any, being offered in such Fundamental Transaction (as determined by the Company in good faith) and (D) a remaining option time equal to the time between the date of the public announcement of the applicable Fundamental Transaction and the Expiration Date. The Company shall cause any successor entity in a Fundamental Transaction in which the Company is not the survivor (the “ Successor Entity ”) to assume in writing all of the obligations of the Company under this Warrant in accordance with the provisions of this Section 4.4, and to deliver to the holder in exchange for this Warrant a security of the Successor Entity evidenced by a written instrument substantially similar in form and substance to this Warrant which is exercisable for a corresponding number of shares of capital stock of such Successor Entity (or its parent entity) equivalent to the shares of Common Stock acquirable and receivable upon exercise of this Warrant (without regard to any limitations on the exercise of this Warrant) prior to such Fundamental Transaction, and with an exercise price which applies the exercise price hereunder to such shares of capital stock (but taking into account the relative value of the shares of Common Stock pursuant to such Fundamental Transaction and the value of such shares

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of capital stock, such number of shares of capital stock and such exercise price being for the purpose of protecting the economic value of this Warrant immediately prior to the consummation of such Fundamental Transaction). Upon the occurrence of any such Fundamental Transaction, the Successor Entity shall succeed to, and be substituted for (so that from and after the date of such Fundamental Transaction, the provisions of this Warrant shall refer instead to the Successor Entity), and may exercise every right and power of the Company and shall assume all of the obligations of the Company under this Warrant with the same effect as if such Successor Entity had been named as the Company herein. As used in this Section 4.4, the term “ Person ” means any foreign or domestic individual, corporation, trust, partnership, joint venture, limited liability company or other private, governmental or self regulatory entity.

4.5 Notices of Changes in Warrant . Upon every adjustment of the Warrant Price or the number of shares issuable upon exercise of a Warrant, the Company shall give written notice thereof to the Warrant Agent, which notice shall state the Warrant Price resulting from such adjustment and the increase or decrease, if any, in the number of shares purchasable at such price upon the exercise of a Warrant, setting forth in reasonable detail the method of calculation and the facts upon which such calculation is based. Upon the occurrence of any event specified in Sections 4.1, 4.2 or 4.3 the Company shall give written notice to each Registered Holder, at the last address set forth for such Registered Holder in the Warrant Register, of the record date or the effective date of the event. Failure to give such notice, or any defect therein, shall not affect the legality or validity of such event.

4.6 Form of Warrant . The form of Warrant need not be changed because of any adjustment pursuant to this Section 4, and Warrants issued after such adjustment may state the same Warrant Price and the same number of shares as is stated in the Warrants initially issued pursuant to this Warrant Agreement. However, the Company may, at any time, in its sole discretion, make any change in the form of Warrant that the Company may deem appropriate and that does not affect the substance thereof, and any Warrant thereafter issued or countersigned, whether in exchange or substitution for an outstanding Warrant or otherwise, may be in the form as so changed.

5. Transfer and Exchange of Warrants .

5.1 Registration of Transfer . The Warrant Agent shall register the transfer, from time to time, of any outstanding Warrant into the Warrant Register, upon surrender of such Warrant for transfer, properly endorsed with signatures properly guaranteed and accompanied by appropriate instructions for transfer. Upon any such transfer, a new Warrant representing an equal aggregate number of Warrants shall be issued and the old Warrant shall be cancelled by the Warrant Agent. The Warrants so cancelled shall be delivered by the Warrant Agent to the Company from time to time upon the Company’s request.

5.2 Procedure for Surrender of Warrants . Warrants may be surrendered to the Warrant Agent, together with a written request for exchange or transfer, and, thereupon, the Warrant Agent shall issue in exchange therefor one or more new Warrants as requested by the Registered Holder of the Warrants so surrendered, representing an equal aggregate number of Warrants.

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5.3 Fractional Warrants . The Warrant Agent shall not be required to effect any registration of transfer or exchange which will result in the issuance of a warrant certificate for a fraction of a warrant.

5.4 Service Charges . No service charge shall be made for any exchange or registration of transfer of Warrants.

5.5 Warrant Execution and Countersignature . The Warrant Agent is hereby authorized to countersign and to deliver, in accordance with the terms of this Warrant Agreement, the Warrants required to be issued pursuant to the provisions of this Section 5, and the Company, whenever required by the Warrant Agent, will supply the Warrant Agent with Warrants duly executed on behalf of the Company for such purpose.

6. [RESERVED] .

7. Other Provisions Relating to Rights of Registered Holders of Warrants .

7.1 No Rights as Stockholder . A Warrant does not entitle the Registered Holder thereof to any of the rights of a stockholder of the Company, including, without limitation, the right to receive dividends, or other distributions, exercise any preemptive rights to vote or to consent or to receive notice as stockholders in respect of the meetings of stockholders or the election of directors of the Company or any other matter.

7.2 Lost, Stolen Mutilated or Destroyed Warrants . If any Warrant is lost, stolen, mutilated or destroyed, the Company and the Warrant Agent may, on such terms as to indemnity or otherwise as they may in their discretion impose (which terms shall, in the case of a mutilated Warrant, include the surrender thereof), issue a new Warrant of like denomination, tenor and date as the Warrant so lost, stolen, mutilated or destroyed. Any such new Warrant shall constitute a substitute contractual obligation of the Company, whether or not the allegedly lost, stolen, mutilated or destroyed Warrant shall be at any time enforceable by anyone.

7.3 Reservation of Common Stock . The Company shall at all times reserve and keep available a number of its authorized but unissued shares of Common Stock that will be sufficient to permit the exercise in full of all outstanding Warrants issued pursuant to this Warrant Agreement. The Company will take all such commercially reasonable action as may be necessary to assure that such Warrant Shares may be issued as provided herein without violation of any applicable law or regulation, or of any requirements of the trading market upon which the Common Stock may be listed.

8. Concerning the Warrant Agent and Other Matters.

8.1 Payment of Taxes . The Company will, from time to time, promptly pay all taxes and charges that may be imposed upon the Company or the Warrant Agent in respect of the issuance or delivery of shares of Common Stock upon the exercise of Warrants, but the Company shall not be obligated to pay any transfer taxes in respect of the Warrants or such shares.

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8.2 Resignation, Consolidation, or Merger of Warrant Agent .

8.2.1 Appointment of Successor Warrant Agent . The Warrant Agent, or any successor to it hereafter appointed, may resign its duties and be discharged from all further duties and liabilities hereunder after giving sixty (60) days’ notice in writing to the Company. If the office of the Warrant Agent becomes vacant by resignation or incapacity to act or otherwise, the Company shall appoint, in writing, a successor Warrant Agent in place of the Warrant Agent. If the Company shall fail to make such appointment within a period of 30 days after it has been notified in writing of such resignation or incapacity by the Warrant Agent or by the Registered Holder of the Warrant (who shall, with such notice, submit his, her or its Warrant for inspection by the Company), then the Registered Holder of any Warrant may apply to the Supreme Court of the State of New York for the County of New York for the appointment of a successor Warrant Agent. Any successor Warrant Agent, whether appointed by the Company or by such court, shall be a corporation organized and existing under the laws of the State of New York, in good standing and having its principal office in the Borough of Manhattan, City and State of New York, and be authorized under such laws to exercise corporate trust powers and subject to supervision or examination by federal or state authorities. After appointment, any successor Warrant Agent shall be vested with all the authority, powers, rights, immunities, duties and obligations of its predecessor Warrant Agent with like effect as if originally named as Warrant Agent hereunder, without any further act or deed; but, if for any reason it becomes necessary or appropriate, the predecessor Warrant Agent shall execute and deliver, at the expense of the Company, an instrument transferring to such successor Warrant Agent all the authority, powers, and rights of such predecessor Warrant Agent hereunder; and, upon request of any successor Warrant Agent, the Company shall make, execute, acknowledge, and deliver any and all instruments in writing for more fully and effectually vesting in and confirming to such successor Warrant Agent all such authority, powers, rights, immunities, duties and obligations.

8.2.2 Notice of Successor Warrant Agent . In the event a successor Warrant Agent shall be appointed, the Company shall give notice thereof to the predecessor Warrant Agent and the transfer agent for the Common Stock not later than the effective date of any such appointment.

8.2.3 Merger or Consolidation of Warrant Agent . Any corporation into which the Warrant Agent may be merged or with which it may be consolidated or any corporation resulting from any merger or consolidation to which the Warrant Agent shall be a party shall be the successor Warrant Agent under this Warrant Agreement without any further act on the part of the Company or the Warrant Agent.

8.3 Fees and Expenses of Warrant Agent .

8.3.1 Remuneration . The Company agrees to pay the Warrant Agent reasonable remuneration for its services as Warrant Agent hereunder and will reimburse the Warrant Agent upon demand for all expenditures that the Warrant Agent may reasonably incur in the execution of its duties hereunder.

8.3.2 Further Assurances . The Company agrees to perform, execute, acknowledge and deliver, or cause to be performed, executed, acknowledged and delivered, all such further and other acts, instruments and assurances as may reasonably be required by the Warrant Agent for the carrying out or performing of the provisions of this Warrant Agreement.

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8.4 Liability of Warrant Agent .

8.4.1 Reliance on Company Statement . Whenever, in the performance of its duties under this Warrant Agreement, the Warrant Agent shall deem it necessary or desirable that any fact or matter be proved or established by the Company prior to taking or suffering any action hereunder, such fact or matter (unless other evidence in respect thereof be herein specifically prescribed) may be deemed to be conclusively proved and established by a statement signed by an officer of the Company and delivered to the Warrant Agent. The Warrant Agent may rely upon such statement for any action taken or suffered in good faith by it pursuant to the provisions of this Warrant Agreement.

8.4.2 Indemnity . The Warrant Agent shall be liable hereunder only for its own gross negligence, willful misconduct or bad faith. The Company agrees to indemnify the Warrant Agent and hold it harmless against any and all liabilities, including judgments, costs and reasonable counsel fees, for anything done or omitted by the Warrant Agent in the execution of this Warrant Agreement, except as a result of the Warrant Agent’s gross negligence, willful misconduct or bad faith.

8.4.3 Exclusions . The Warrant Agent shall have no responsibility with respect to the validity of this Warrant Agreement or with respect to the validity or execution of any Warrant (except its countersignature thereof); nor shall it be responsible for any breach by the Company of any covenant or condition contained in this Warrant Agreement or in any Warrant; nor shall it be responsible to make any adjustments required under the provisions of Section 4 hereof or responsible for the manner, method or amount of any such adjustment or the ascertaining of the existence of facts that would require any such adjustment; nor shall it, by any act hereunder, be deemed to make any representation or warranty as to the authorization or reservation of any shares of Common Stock to be issued pursuant to this Warrant Agreement or any Warrant or as to whether any shares of Common Stock will when issued be valid and fully paid and non-assessable.

8.5 Acceptance of Agency . The Warrant Agent hereby accepts the agency established by this Warrant Agreement and agrees to perform the same upon the terms and conditions herein set forth and, among other things, shall account promptly to the Company with respect to Warrants exercised and concurrently account for, and pay to the Company, all moneys received by the Warrant Agent for the purchase of shares of the Company’s Common Stock through the exercise of Warrants.

9. Miscellaneous Provisions .

9.1 Successors . All the covenants and provisions of this Warrant Agreement by or for the benefit of the Company or the Warrant Agent shall bind and inure to the benefit of their respective successors and assigns.

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9.2 Notices . Any notice, statement or demand authorized by this Warrant Agreement to be given or made by the Warrant Agent or by the Registered Holder of any Warrant to or on the Company shall be delivered by hand or sent by registered or certified mail or overnight courier service, addressed (until another address is filed in writing by the Company with the Warrant Agent) as follows:

ContraFect Corporation

28 Wells Avenue, Third Floor

Yonkers, New York 10701

(914) 207-2300

Attention: Michael Messinger

and

Latham & Watkins LLP

200 Clarendon Ave.

Boston, MA 02116

Tel: (617) 948-6000

Fax: (617) 948-6001

Attention: Peter N. Handrinos

Any notice, statement or demand authorized by this Warrant Agreement to be given or made by the Registered Holder of any Warrant or by the Company to or on the Warrant Agent shall be delivered by hand or sent by registered or certified mail or overnight courier service, addressed (until another address is filed in writing by the Warrant Agent with the Company), as follows:

American Stock Transfer & Trust Company, LLC

6201 15th Avenue

Brooklyn, New York 11219

2nd floor—Reorganization Department

Any notice, sent pursuant to this Warrant Agreement shall be effective, if delivered by hand, upon receipt thereof by the party to whom it is addressed, if sent by overnight courier, on the next business day of the delivery to the courier, and if sent by registered or certified mail on the third day after registration or certification thereof

9.3 Applicable Law . The validity, interpretation, and performance of this Warrant Agreement and of the Warrants shall be governed in all respects by the laws of the State of New York. The Company and the Warrant Agent hereby agree that any action, proceeding or claim against either of them arising out of or relating in any way to this Warrant Agreement shall be brought and enforced in the courts of the State of New York or the United States District Court for the Southern District of New York, and irrevocably submits to such jurisdiction, which jurisdiction shall be exclusive. The Company and the Warrant Agent hereby waive any objection to such exclusive jurisdiction and that such courts represent an inconvenient forum. Any such process or summons to be served upon the Company or the Warrant Agent may be served by transmitting a copy thereof by registered or certified mail, return receipt requested, postage prepaid, addressed to it at the address set forth in Section 9.2 hereof. Such mailing shall be deemed personal service and shall be legal and binding upon the party receiving such service in any action, proceeding or claim.

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9.4 Persons Having Rights under this Warrant Agreement . Nothing in this Warrant Agreement expressed and nothing that may be implied from any of the provisions hereof is intended, or shall be construed, to confer upon, or give to, any person or corporation other than the parties hereto and the Registered Holders of the Warrants. All covenants, conditions, stipulations, promises, and agreements contained in this Warrant Agreement shall be for the sole and exclusive benefit of the parties hereto and their successors and assigns and of the Registered Holders of the Warrants.

9.5 Examination of the Warrant Agreement . A copy of this Warrant Agreement shall be available at all reasonable times at the office of the Warrant Agent in the Borough of Manhattan, City and State of New York, for inspection by the Registered Holder of any Warrant. The Warrant Agent may require any such Registered Holder to submit his, her or its Warrant for inspection.

9.6 Counterparts — Facsimile Signatures . This Warrant Agreement may be executed in any number of counterparts, and each of such counterparts shall, for all purposes, be deemed to be an original, and all such counterparts shall together constitute one and the same instrument. Facsimile signatures shall constitute original signatures for all purposes of this Warrant Agreement.

9.7 Effect of Headings . The section headings herein are for convenience only and are not part of this Warrant Agreement and shall not affect the interpretation thereof

9.8 Amendments . This Warrant Agreement and any Warrant certificate may be amended by the parties hereto by executing a supplemental warrant agreement, without the consent of any of the Warrant Holders, for the purpose of (i) curing any ambiguity, or curing, correcting or supplementing any defective provision contained herein, or making any other provisions with respect to matters or questions arising under this Warrant Agreement that is not inconsistent with the provisions of this Warrant Agreement or the Warrant certificates, (ii) evidencing the succession of another corporation to the Company and the assumption by any such successor of the covenants of the Company contained in this Warrant Agreement and the Warrants, (iii) evidencing and providing for the acceptance of appointment by a successor Warrant Agent with respect to the Warrants, (iv) adding to the covenants of the Company for the benefit of the Registered Holders or surrendering any right or power conferred upon the Company under this Warrant Agreement, or (viii) amending this Warrant Agreement and the Warrants in any manner that the Company may deem to be necessary or desirable and that will not adversely affect the interests of the Registered Holders in any material respect. All other modifications or amendments to this Warrant Agreement, including any amendment to increase the Warrant Price or shorten the Exercise Period, shall require the written consent of the Registered Holders of a majority of the then outstanding Warrants. Notwithstanding the foregoing, the Company may extend the duration of the Exercise Period in accordance with Section 3.2 without such consent.

9.9 Severability . This Warrant Agreement shall be deemed severable, and the invalidity or unenforceability of any term or provision hereof shall not affect the validity or enforceability of this Warrant Agreement or of any other term or provision hereof. Furthermore, in lieu of any such invalid or unenforceable term or provision, the parties hereto intend that there shall be added as a part of this Warrant Agreement a provision as similar in terms to such invalid or unenforceable provision as may be possible and be valid and enforceable.

[SIGNATURE PAGE FOLLOWS]

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IN WITNESS WHEREOF, this Warrant Agreement has been duly executed by the parties hereto as of the day and year first above written.

[SIGNATURE PAGE TO THE WARRANT AGREEMENT]

EXHIBIT A

[FORM OF WARRANT CERTIFICATE]

[UNLESS THIS GLOBAL WARRANT CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”) TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR’S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE WARRANT AGREEMENT REFERRED TO ON THE REVERSE HEREOF.

ANY TRANSFER OF THE SECURITIES REPRESENTED BY THIS GLOBAL WARRANT CERTIFICATE IS SUBJECT TO THE CONDITIONS SPECIFIED IN THE WARRANT AGREEMENT (THE “WARRANT AGREEMENT”) DATED AS OF JULY 27, 2016 BETWEEN CONTRAFECT CORPORATION AND AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC, SOLELY IN ITS CAPACITY AS WARRANT AGENT. BY ACCEPTING DELIVERY OF THE SECURITIES REPRESENTED BY THIS GLOBAL WARRANT CERTIFICATE, ANY TRANSFEREE SHALL BE DEEMED TO HAVE AGREED TO BE BOUND BY THE WARRANT AGREEMENT AS IF THE TRANSFEREE HAD EXECUTED AND DELIVERED THE WARRANT AGREEMENT.

EXERCISABLE ON OR AFTER JULY 27, 2016

AND UNTIL 5:00 P.M. (NEW YORK TIME) ON THE EXPIRATION DATE] ¹

WARRANT CERTIFICATE

(THIS WARRANT WILL BE VOID IF NOT EXERCISED PRIOR TO 5:00 P.M.

NEW YORK CITY TIME, SIXTY (60) MONTHS FROM THE DATE OF ORIGINAL ISSUANCE)

CONTRAFECT CORPORATION

CUSIP [            ]

WARRANT

THIS WARRANT CERTIFIES THAT, for value received [                    ], or registered agents, is the registered holder of a Warrant or Warrants (the “ Warrant ”) expiring on a date which is sixty (60) months from the original date of issuance on July 27, 2016, to purchase [                    ] fully paid and non-assessable shares of common stock, par value $0.0001 per share (the “ Shares ”), of CONTRAFECT CORPORATION, a Delaware corporation (the “ Company ”), for each Warrant evidenced by this Warrant Certificate. This Warrant Certificate is subject to and shall be interpreted under the terms and conditions of the Warrant Agreement (as defined below).

The Warrant entitles the holder thereof to purchase from the Company, commencing upon the original issuance of the Warrant on July 27, 2016, such number of Shares at the price of $3.00 per share (the “ Warrant Price ”), upon surrender of this Warrant Certificate and payment of the Warrant Price at the office or agency of American Stock Transfer & Trust Company, LLC (the “ Warrant Agent ”), such payment to be made by check made payable to the Warrant Agent (or pursuant to the cashless exercise procedure specified in Section 3.3.3 of the Warrant Agreement, if such cashless exercise procedure is applicable, but only subject to the conditions set forth herein and in the Warrant Agreement, dated July 27, 2016, between the Company and the Warrant Agent (the “ Warrant Agreement ”). In the event of any conflict between the terms of this Warrant Certificate and the terms of the Warrant Agreement, the terms of the Warrant Agreement shall govern. The Warrant Agreement provides that, upon the occurrence of certain events, the Warrant Price and the number of Warrant Shares purchasable hereunder, set forth on the face hereof, may be adjusted, subject to certain conditions. The term Warrant Price as used in this Warrant Certificate refers to the price per Share at which Shares may be purchased at the time the Warrant is exercised.

This Warrant will expire on the date first referenced above if it is not exercised prior to such date by the registered holder pursuant to the terms of the Warrant Agreement or if it is redeemed by the Company prior to such date as described below.

No fraction of a Share will be issued upon any exercise of a Warrant. If, upon exercise of a Warrant, a holder would be entitled to receive a fractional interest in a Share, the Company will, upon exercise, issue or cause to be issued only the largest whole number of Shares issuable on such exercise (and such fraction of a Share will be disregarded).

Upon any exercise of the Warrant for less than the total number of full Shares provided for herein, there shall be issued to the registered holder(s) hereof or its assignee(s) a new Warrant Certificate covering the number of Shares for which the Warrant has not been exercised.

Warrant Certificates, when surrendered at the office or agency of the Warrant Agent by the registered holder(s) hereof in person or by attorney duly authorized in writing, may be exchanged in the manner and subject to the limitations provided in the Warrant Agreement, but without payment of any service charge, for another Warrant Certificate or Warrant Certificates of like tenor and evidencing in the aggregate a like number of Warrants.

Upon due presentment for registration of transfer of the Warrant Certificate at the office or agency of the Warrant Agent, a new Warrant Certificate or Warrant Certificates of like tenor and evidencing in the aggregate a like number of Warrants shall be issued to the transferee(s) in exchange for this Warrant Certificate, subject to the limitations provided in the Warrant Agreement, without charge except for any applicable tax or other governmental charge.

The Company and the Warrant Agent may deem and treat the registered holder(s) as the absolute owner(s) of this Warrant Certificate (notwithstanding any notation of ownership or other writing hereon made by anyone) for the purpose of any exercise hereof, of any distribution to the registered holder(s), and for all other purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.

This Warrant does not entitle the registered holder(s) to any of the rights of a stockholder of the Company.

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IN WITNESS WHEREOF, the undersigned have caused this Global Warrant Certificate to be executed as of the date set forth below.

[Signature page to [Global] Warrant Certificate]

[REVERSE OF CERTIFICATE]

SUBSCRIPTION FORM

T O B E E XECUTED BY THE R EGISTERED H OLDER ( S ) IN O RDER TO E XERCISE W ARRANTS

and deliver the physical certificate representing said Warrant Shares to the following address:

If the Warrant Shares will be delivered electronically via DWAC, please issue them to the following account:

[Warrant Shares Exercise Log] ²

ASSIGNMENT

T O B E E XECUTED BY THE R EGISTERED H OLDER IN O RDER TO A SSIGN W ARRANTS

For Value Received,                                          hereby sell(s), assign(s), and transfer(s) unto

(SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER(S))

(SOCIAL SECURITY OR TAX IDENTIFICATION NUMBER(S))

of the Warrants represented by this Warrant Certificate, and hereby irrevocably constitute and appoint                                          Attorney to transfer this Warrant Certificate on the books of the Company, with full power of substitution in the premises.

Dated:

NOTICE: THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed:

THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15).