RISK FACTORS

The combined organization will be faced with a market environment that cannot be predicted and that involves significant risks, many of which will be beyond its control. In addition to the other information contained in this proxy statement/prospectus/information statement, you should carefully consider the material risks described below before deciding how to vote your shares of stock. In addition, you should read and consider the risks associated with the business of Celladon because these risks may also affect the combined company—these risks can be found in Celladon’s Annual Report on Form 10-K, as updated by subsequent Quarterly Reports on Form 10-Q, all of which are filed with the SEC. You should also read and consider the other information in this proxy statement/prospectus/information statement and the other documents incorporated by reference into this proxy statement/prospectus/information statement. Please see the section entitled “Where You Can Find More Information” in this proxy statement/prospectus/information statement.

Risks Related to the Merger

The exchange ratio is not adjustable based on the market price of Celladon common stock so the merger consideration at the closing may have a greater or lesser value than at the time the Merger Agreement was signed.

The Merger Agreement has set the exchange ratio for the Eiger common stock, and the exchange ratio is only adjustable upward or downward if the outstanding capital stock of Eiger or the outstanding common stock of Celladon changes based upon certain events, including the proposed 1-for-15 reverse stock split, prior to completion of the merger as described in “The Merger—Merger Consideration and Adjustment.” Any changes in the market price of Celladon common stock before the completion of the merger will not affect the number of shares Eiger securityholders will be entitled to receive pursuant to the Merger Agreement. Therefore, if before the completion of the merger the market price of Celladon common stock declines from the market price on the date of the Merger Agreement, then Eiger securityholders could receive merger consideration with substantially lower value. Similarly, if before the completion of the merger the market price of Celladon common stock increases from the market price on the date of the Merger Agreement, then Eiger securityholders could receive merger consideration with substantially more value for their shares of Eiger capital stock than the parties had negotiated for in the establishment of the exchange ratio. The Merger Agreement does not include a price-based termination right, however, Eiger’s obligation to consummate the Merger is conditioned upon Celladon having “Net Cash” of at least $24 million, as defined and described under “The Merger Agreement—Conditions to the Completion of the Merger.” Because the exchange ratio does not adjust as a result of changes in the value of Celladon common stock, for each one percentage point that the market value of Celladon common stock rises or declines, there is a corresponding one percentage point rise or decline, respectively, in the value of the total merger consideration issued to Eiger securityholders.

Failure to complete the merger may result in Celladon and Eiger paying a termination fee or expenses to the other party and could harm the common stock price of Celladon and future business and operations of each company.

If the merger is not completed, Celladon and Eiger are subject to the following risks:

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In addition, if the Merger Agreement is terminated and the board of directors of Celladon or Eiger determines to seek another business combination, there can be no assurance that either Celladon or Eiger will be able to find a partner willing to provide equivalent or more attractive consideration than the consideration to be provided by each party in the merger.

If the conditions to the merger are not met, the merger may not occur.

Even if the merger is approved by the stockholders of Celladon and Eiger, specified conditions must be satisfied or waived to complete the merger. These conditions are set forth in the Merger Agreement and described in the section entitled “The Merger Agreement—Conditions to the Completion of the Merger” in this proxy statement/prospectus/information statement. Celladon and Eiger cannot assure you that all of the conditions will be satisfied or waived. If the conditions are not satisfied or waived, the merger may not occur or will be delayed, and Celladon and Eiger each may lose some or all of the intended benefits of the merger.

The merger may be completed even though material adverse changes may result from the announcement of the merger, industry-wide changes and other causes.

In general, either Celladon or Eiger can refuse to complete the merger if there is a material adverse change affecting the other party between November 18, 2015, the date of the Merger Agreement, and the closing. However, certain types of changes do not permit either party to refuse to complete the merger, even if such change could be said to have a material adverse effect on Celladon or Eiger, including:

If adverse changes occur and Celladon and Eiger still complete the merger, the combined organization stock price may suffer. This in turn may reduce the value of the merger to the stockholders of Celladon, Eiger or both.

Some Celladon and Eiger executive officers and directors have interests in the merger that are different from yours and that may influence them to support or approve the merger without regard to your interests.

Certain officers and directors of Celladon and Eiger participate in arrangements that provide them with interests in the merger that are different from yours, including, among others, the continued service as an officer or

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director of the combined organization, severance and retention benefits, incentive payments upon achievement of key milestones relating to the merger, the acceleration of stock option vesting, continued indemnification and the potential ability to sell an increased number of shares of common stock of the combined organization in accordance with Rule 144 under the Securities Act of 1933, as amended, or the Securities Act.

For example, Celladon has entered into employment agreements with each of its executive officers that provide for severance benefits. In addition, pursuant to a retention program adopted on April 26, 2015 and amended on May 13, 2015, Celladon entered into retention agreements with certain current and former executive officers which provided for retention payments if such officers remained employed with Celladon until December 31, 2015 or were terminated without cause prior to that date. In connection with execution of the Merger Agreement, effective November 18, 2015, Celladon entered into agreements with each of Messrs. Wiklund and Jackson and Ms. Reed, the sole remaining employees of Celladon, providing for a cash bonus payment (an “Executive Bonus Payment”) to each of them in an amount equal to the cash severance and retention benefit payments provided in each officer’s previously existing agreements. The Executive Bonus Payment for each officer equals the cash payment amount that each such officer would have been entitled to under the terms of his or her employment agreement, as amended, and his or her retention agreement dated May 27, 2015 that was entered into pursuant to the retention program adopted on April 26, 2015 and amended on May 13, 2015 (collectively, the “Prior Agreements”) had such officer been terminated without cause or resigned for good reason (or, with respect to the retention agreements, remained employed by Celladon on December 31, 2015), and replaces and supersedes each officer’s right to any cash severance or retention benefits under the Prior Agreements. Each officer’s Executive Bonus Payment will be subject to his or her delivery of an effective waiver and release of claims and is expected to be paid in late 2015 or early 2016. Each of Messrs. Wiklund’s and Jackson’s and Ms. Reed’s employment relationship with Celladon remains at-will and continued employment with Celladon is not a requirement to receive the Executive Bonus Payment. The closing of the merger will also result in the acceleration of vesting of options to purchase shares of Celladon common stock held by the Celladon directors. For more information concerning the treatment of Celladon options in connection with the merger, see the section entitled “The Merger Agreement—Treatment of Celladon Stock Options and Warrants” in this proxy statement/prospectus/information statement. In addition, Celladon adopted an incentive bonus program for Celladon’s remaining three officers, who are the sole remaining employees of Celladon, pursuant to which they will be eligible to receive incentive payments upon the achievement of the following key milestones: (i) filing of the registration statement on Form S-4 in respect of the proposed merger; (ii) mailing of the proxy statement/prospectus/information statement portion of such registration statement on Form S-4 to the Celladon stockholders; and (iii) approval of the Merger by Celladon’s stockholders. Subject to achievement and provided that such officer remains employed with Celladon as of the date of such milestone achievement, Mr. Wiklund will be eligible to receive a payment of $50,000 for each milestone, and each of Mr. Jackson and Ms. Reed will be eligible to receive a payment of $40,000 for each milestone.

In addition, certain of Eiger’s officers received grants of shares of Eiger common stock prior to the execution of the Merger Agreement, certain of Eiger’s directors and executive officers have options, subject to vesting, to purchase shares of Eiger common stock which will be converted into and become options to purchase shares of Celladon common stock, certain of Eiger’s directors and executive officers are expected to become directors and executive officers of Celladon upon the closing of the merger and all of Celladon’s and Eiger’s directors and executive officers are entitled to certain indemnification and liability insurance coverage pursuant to the terms of the Merger Agreement. These interests, among others, may influence the officers and directors of Celladon and Eiger to support or approve the merger. For more information concerning the interests of Celladon and Eiger executive officers and directors, see the sections entitled “The Merger—Interests of the Celladon Directors and Executive Officers in the Merger” and “The Merger—Interests of the Eiger Directors and Executive Officers in the Merger” in this proxy statement/prospectus/information statement.

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The market price of Celladon common stock following the merger may decline as a result of the merger.

The market price of Celladon common stock may decline as a result of the merger for a number of reasons including if:

Celladon and Eiger stockholders may not realize a benefit from the merger commensurate with the ownership dilution they will experience in connection with the merger.

If the combined organization is unable to realize the full strategic and financial benefits currently anticipated from the merger, Celladon and Eiger stockholders will have experienced substantial dilution of their ownership interests in their respective companies without receiving any commensurate benefit, or only receiving part of the commensurate benefit to the extent the combined organization is able to realize only part of the strategic and financial benefits currently anticipated from the merger.

During the pendency of the merger, Celladon and Eiger may not be able to enter into a business combination with another party at a favorable price because of restrictions in the Merger Agreement, which could adversely affect their respective businesses.

Covenants in the Merger Agreement impede the ability of Celladon and Eiger to make acquisitions, subject to certain exceptions relating to fiduciaries duties, as set forth below, or complete other transactions that are not in the ordinary course of business pending completion of the merger. As a result, if the merger is not completed, the parties may be at a disadvantage to their competitors during that period. In addition, while the Merger Agreement is in effect, each party is generally prohibited from soliciting, initiating, encouraging or entering into certain extraordinary transactions, such as a merger, sale of assets or other business combination outside the ordinary course of business, with any third party, subject to certain exceptions described below. Any such transactions could be favorable to such party’s stockholders.

Certain provisions of the Merger Agreement may discourage third parties from submitting alternative takeover proposals, including proposals that may be superior to the arrangements contemplated by the Merger Agreement.

The terms of the Merger Agreement prohibit each of Celladon and Eiger from soliciting alternative takeover proposals or cooperating with persons making unsolicited takeover proposals, except in limited circumstances when such party’s board of directors determines in good faith that an unsolicited alternative takeover proposal is or is reasonably likely to lead to a superior takeover proposal and is reasonably capable of being consummated and that failure to cooperate with the proponent of the proposal is reasonably likely to result in a breach of the board’s fiduciary duties. In addition, if Celladon or Eiger terminate the Merger Agreement under certain circumstances, including terminating because of a decision of a board of directors to recommend a superior proposal, Celladon or Eiger would be required to pay a termination fee of $3.0 million to the other party. If the Merger Agreement is terminated under certain circumstances, Celladon or Eiger will be required to pay the other party a termination fee of $3.0 million or, in some circumstances, reimburse the other party for expenses incurred in connection with the merger, up to a maximum of $1.0 million. This termination fee may discourage third parties from submitting alternative takeover proposals to Celladon or Eiger or their stockholders, and may cause the respective boards of directors to be less inclined to recommend an alternative proposal.

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Because the lack of a public market for Eiger shares makes it difficult to evaluate the fairness of the merger, the stockholders of Eiger may receive consideration in the merger that is less than the fair market value of the Eiger shares and/or Celladon may pay more than the fair market value of the Eiger shares.

The outstanding capital stock of Eiger is privately held and is not traded in any public market. The lack of a public market makes it extremely difficult to determine the fair market value of Eiger. Because the percentage of Celladon equity to be issued to Eiger stockholders was determined based on negotiations between the parties, it is possible that the value of the Celladon common stock to be received by Eiger stockholders will be less than the fair market value of Eiger, or Celladon may pay more than the aggregate fair market value for Eiger.

Risks Related to Celladon

Celladon’s business to date has been almost entirely dependent on the success of MYDICAR, which recently failed to show a treatment effect in the Phase 2b clinical trial known as CUPID 2. Following the analysis of the data from CUPID 2, Celladon decided to substantially suspend further research and development while seeking a merger or sale, and there is no guarantee that this strategic path will be successful.

On April 26, 2015, Celladon announced that the CUPID 2 trial did not meet its primary and secondary endpoints. CUPID 2 was a 250-patient randomized, double-blind, placebo-controlled multinational Phase 2b trial that was designed to evaluate MYDICAR in patients with heart failure with reduced ejection fraction, or HFrEF, also referred to as systolic heart failure. Celladon had previously devoted substantially all of its research, development and clinical efforts and financial resources toward the development of MYDICAR. As a result of the negative results from CUPID 2, Celladon has suspended further research and development of MYDICAR and its pre-clinical programs to reduce operating expenses while seeking a merger or sale. There can be no assurance that the proposed merger transaction will be approved or consummated, or if consummated, that it would enhance shareholder value. If the merger is not consummated, there also can be no assurance that Celladon will conduct drug development activities in the future.

There is no assurance that the proposed merger between Celladon and Eiger will be completed in a timely manner or at all. If the merger with Eiger is not consummated, Celladon’s business could suffer materially and its stock price could decline.

The consummation of the proposed merger between Celladon and Eiger is subject to a number of closing conditions, including the approval by Celladon’s stockholders and other customary closing conditions. The parties are targeting a closing of the transaction in the first half of 2016, however, there can be no assurance that the proposed merger will be consummated on their desired timeframe, or at all.

If the proposed merger between Celladon and Eiger is not consummated, Celladon may be subject to a number of material risks, and its business and stock price could be adversely affected, as follows:

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If the merger is not completed, Celladon’s board of directors may decide to pursue a dissolution and liquidation of the company. In such an event, the amount of cash available for distribution to its stockholders will depend heavily on the timing of such liquidation as well as the amount of cash that will need to be reserved for commitments and contingent liabilities.

There can be no assurance that the merger will be completed. If the merger is not completed, Celladon’s board of directors may decide to pursue a dissolution and liquidation of the company. In such an event, the amount of cash available for distribution to its stockholders will depend heavily on the timing of such decision, as with the passage of time the amount of cash available for distribution will be reduced as Celladon continues to fund its operations. In addition, if Celladon’s board of directors were to approve and recommend, and its stockholders were to approve, a dissolution and liquidation of the company, it would be required under Delaware corporate law to pay its outstanding obligations, as well as to make reasonable provision for contingent and unknown obligations, prior to making any distributions in liquidation to its stockholders. Celladon’s commitments and contingent liabilities may include: (i) regulatory and clinical obligations remaining under its CUPID 2 trial, which is currently in the long-term follow up stage until February 2016; (ii) the pending litigation against Celladon, and other various claims and legal actions arising in the ordinary course of business; and (iii) non-cancelable lease obligations. As a result of this requirement, a portion of Celladon’s assets may need to be reserved pending the resolution of such obligations. In addition, Celladon may be subject to litigation or other claims related to a dissolution and liquidation of its company. If a dissolution and liquidation were pursued, Celladon’s board of directors, in consultation with its advisors, would need to evaluate these matters and make a determination about a reasonable amount to reserve. Accordingly, holders of its common stock could lose all or a significant portion of their investment in the event of a liquidation, dissolution or winding up of its company.

If Celladon fails to continue to meet all applicable NASDAQ Global Market requirements and NASDAQ determines to delist Celladon’s common stock, the delisting could adversely affect the value of the merger, market liquidity of its common stock and the market price of its common stock could decrease.

Celladon’s common stock is listed on The NASDAQ Global Market. In order to maintain the listing, Celladon must meet minimum financial and other requirements, including requirements for a minimum amount of capital, a minimum price per share and continued business operations so that it is not characterized as a “public shell company.” If Celladon is unable to comply with NASDAQ’s listing standards, NASDAQ may determine to delist its common stock from The NASDAQ Global Market. If its common stock is delisted for any reason, it could reduce the value of its common stock and its liquidity. Delisting could also adversely affect the ability to obtain financing for the continuation of Celladon’s operations, if Celladon chooses to reestablish its business, or to use its common stock in acquisitions, including the merger. Delisting could result in the loss of confidence by suppliers and employees. Delisting would prevent Celladon from satisfying a closing condition for the merger, and, in such event, Eiger may elect not to consummate the merger. In addition, the combined organization must submit a new application for listing on The NASDAQ Global Market after the merger pursuant to the reverse merger rules, and the combined organization will need to meet NASDAQ’s minimum listing requirements.

As a result of the CUPID 2 data and the reductions in Celladon’s workforce announced in April 2015, June 2015 and November 2015, Celladon has only three employees remaining. If Celladon is unable to retain the remaining three employees, Celladon’s ability to consummate the planned merger transaction may be delayed or seriously jeopardized.

On April 30, 2015, June 26, 2015 and November 18, 2015, Celladon announced workforce reductions, which have reduced the headcount to three remaining employees. Celladon’s cash conservation activities may yield unintended consequences, such as attrition beyond the planned reductions in workforce and reduced employee morale which may cause the remaining three employees to seek alternate employment. Competition among biotechnology companies for qualified employees is intense, and the ability to retain the remaining employees is critical to Celladon’s ability to effectively manage its resources following the CUPID 2 data and to consummate the planned merger transaction. Additional attrition could have a material adverse effect on Celladon’s business. In addition, as a result of the reduction in Celladon’s workforce, Celladon faces an increased risk of employment litigation.

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Risks Related to Celladon’s Financial Condition

Celladon has incurred significant losses since its inception and anticipates that it will continue to incur significant losses for the foreseeable future.

Celladon is a biotechnology company and it has not yet generated any revenues. Celladon has incurred net losses in each year since its inception in December 2000, including consolidated net losses of $33.9 million for the year ended December 31, 2014. As of September 30, 2015, Celladon had an accumulated deficit of approximately $186.1 million. Its prior losses, combined with expected future losses, have had and may continue to have an adverse effect on its stockholders’ equity and working capital.

Prior to the recent suspension of its further research and clinical development activities, Celladon had devoted most of its financial resources to research and development, including developing its manufacturing capabilities and preclinical and clinical development activities. To date, Celladon has financed its operations primarily through the sale of equity securities and convertible debt. The amount of its future net losses will depend, in part, on the rate of its future expenditures and its ability to obtain funding through equity or debt financings or strategic collaborations.

The net losses Celladon incurs may fluctuate significantly from quarter-to-quarter and year-to-year, such that a period-to-period comparison of its results of operations may not be a good indication of its future performance. In any particular quarter or quarters, its operating results could be below the expectations of securities analysts or investors, which could cause its stock price to decline.

If the merger is not completed, Celladon would need to raise substantial additional funding to the extent it continues its product development efforts, which may not be available on acceptable terms, or at all. Failure to obtain this necessary capital when needed may force it to delay, limit or terminate its product development efforts or other operations.

Celladon’s operations have consumed substantial amounts of cash since inception. As of September 30, 2015, its cash, cash equivalents and investments were approximately $37.1 million. Celladon’s research and development expenses were $21.8 million and $15.5 million for the nine months ended September 30, 2015 and 2014, respectively. Celladon believes that its existing cash, cash equivalents and investments will enable it to fund its operations for at least the next 12 months. However, drug development is expensive and time-consuming and if Celladon undertakes development efforts, it will need to raise substantial additional capital to fund future activities.

Any additional fundraising efforts may divert Celladon’s management from their day-to-day activities, which may adversely affect its ability to develop and commercialize product candidates. In addition, it cannot guarantee that future financing will be available in sufficient amounts or on terms acceptable to Celladon, if at all. It could also be required to seek funds through arrangements with collaborative partners or otherwise at an earlier stage than would otherwise be ideal and it may be required to relinquish rights to some of its technologies, product candidates, or otherwise agree to terms unfavorable to it, any of which may have a material adverse effect on its business, operating results and prospects.

If Celladon is unable to obtain funding on a timely basis, it may be required to significantly curtail, delay or discontinue one or more of its research or development programs or the commercialization of any approved products, or be unable to deploy the capital necessary to refocus or expand its operations or otherwise capitalize on its business opportunities, as desired, any of which could materially adversely affect its business, financial condition and results of operations and could even require it to cease operations entirely.

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Celladon has never generated any revenue from product sales and may never be profitable.

Celladon’s ability to generate meaningful revenue and achieve profitability depends on its ability, and the ability of any third party with which it may partner, to successfully complete the development of, and obtain the regulatory approvals necessary to, commercialize product candidates. Celladon does not anticipate generating revenues from product sales for the foreseeable future, if ever. If any future product candidates fail in clinical trials or do not gain regulatory approval, or if any product candidates, if approved, fail to achieve market acceptance, Celladon may never become profitable. Even if it achieves profitability in the future, Celladon may not be able to sustain profitability in subsequent periods. Celladon’s ability to generate future revenues from product sales will depend heavily on its success in:

Even if one or more product candidates is approved for commercial sale, Celladon anticipates incurring significant costs associated with commercializing any approved product. Its expenses could increase beyond expectations if it is required by the U.S. Food and Drug Administration, or FDA, the European Medicines Agency, or EMA, or other foreign regulatory authorities to perform clinical trials and other studies in addition to those that it originally anticipated. Even if it is able to generate revenues from the sale of any approved products, Celladon may not become profitable and may need to obtain additional funding to continue operations.

Raising additional funds through debt or equity financing is likely to be difficult, could be dilutive and may cause the market price of Celladon’s common stock to decline further.

To the extent that Celladon raises additional capital through the sale of equity or convertible debt securities, the issuance of those securities could result in substantial dilution for Celladon’s current stockholders and the terms may include liquidation or other preferences that adversely affect the rights of its current stockholders. Furthermore, the issuance of additional securities, whether equity or debt, by Celladon, or the possibility of such issuance, may cause the market price of its common stock to decline further and existing stockholders may not agree with its financing plans or the terms of such financings.

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Even if Celladon resumes or initiates and completes any necessary preclinical studies and clinical trials for any product candidates it may choose to develop, it cannot predict when, or if, it will obtain regulatory approval to commercialize a product candidate or the approval may be for a more narrow indication than Celladon expects.

Even if Celladon resumes or initiates any necessary preclinical studies and clinical trials for any product candidates it may choose to develop, it cannot commercialize a product until the appropriate regulatory authorities have reviewed and approved the product candidate. Even if Celladon’s product candidates demonstrate safety and efficacy in clinical trials, the regulatory agencies may not complete their review processes in a timely manner, or Celladon may not be able to obtain regulatory approval. Additional delays may result if an FDA advisory committee or other regulatory authority recommends non-approval or restrictions on approval. In addition, Celladon may experience delays or rejections based upon additional government regulation from future legislation or administrative action, or changes in regulatory agency policy during the period of product development, clinical trials and the review process. Regulatory agencies also may approve a treatment candidate for fewer or more limited indications than requested or may grant approval subject to the performance of post-marketing studies. In addition, regulatory agencies may not approve the labeling claims that are necessary or desirable for the successful commercialization of Celladon’s treatment candidates.

Even if Celladon obtains regulatory approval for a product candidate, its products will remain subject to regulatory scrutiny.

Even if Celladon obtains regulatory approval in a jurisdiction, regulatory authorities may still impose significant restrictions on the indicated uses or marketing of its product candidates, or impose ongoing requirements for potentially costly post-approval studies or post-market surveillance.

In addition, product manufacturers and their facilities are subject to payment of user fees and continual review and periodic inspections by the FDA and other regulatory authorities. If Celladon or a regulatory agency discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency or problems with the facility where the product is manufactured, a regulatory agency may impose restrictions relative to that product or the manufacturing facility, including requiring recall or withdrawal of the product from the market or suspension of manufacturing.

If Celladon fails to comply with applicable regulatory requirements following approval of any of its product candidates, a regulatory agency may:

Any government investigation of alleged violations of law could require Celladon to expend significant time and resources in response and could generate negative publicity. The occurrence of any event or penalty described above may inhibit Celladon’s ability to commercialize its product candidates and generate revenues.

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Risks Related to Celladon’s Reliance on Third Parties

Celladon relies on third parties to conduct, supervise and monitor its business operations. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, Celladon may not be able to conduct its business and operations and its status as a publicly traded company could be substantially harmed.

Celladon has historically relied on third party vendors for its development work, and since the termination of MYDICAR as a product candidate and the announcement of the merger, certain administrative functions. Celladon’s vendors are not its employees, and there can be no assurance of any ability to directly monitor whether or not the vendors devote sufficient time and resources in furtherance of the company. These vendors may also have relationships with other parties that receive priority over the activities of Celladon. If its vendors do not successfully carry out their contractual duties or obligations, fail to meet expected deadlines, or if the quality or accuracy of the work required to complete the merger and maintain Celladon’s status as a NASDAQ-listed company is not sufficient, its financial results and the commercial prospects for its business would be harmed, its costs to regain compliance could increase, and its ability to identify alternatives for its business and generate revenues would be delayed or significantly impaired.

Healthcare reform measures may have a material adverse effect on Celladon’s business and results of operations.

In the United States, the legislative landscape continues to evolve. In March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or the Affordable Care Act, was passed, which has the potential to substantially change health care financing by both governmental and private insurers, and significantly impact the U.S. pharmaceutical industry. The Affordable Care Act, among other things, subjects biological products to potential competition by lower-cost biosimilars, revised the methodology by which rebates owed by manufacturers for covered outpatient drugs under the Medicaid Drug Rebate Program are calculated, increased the minimum Medicaid rebates owed by most manufacturers under the Medicaid Drug Rebate Program, extended the Medicaid Drug Rebate Program to utilization of prescriptions of individuals enrolled in Medicaid managed care organizations, subjected manufacturers to new annual fees and taxes for certain branded prescription drugs, and provided incentives to programs that increase the federal government’s comparative effectiveness research.

In addition, other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted. On August 2, 2011, the Budget Control Act of 2011 among other things, created measures for spending reductions by Congress. A Joint Select Committee on Deficit Reduction, tasked with recommending a targeted deficit reduction of at least $1.2 trillion for the years 2013 through 2021, was unable to reach required goals, thereby triggering the legislation’s automatic reduction to several government programs. This includes aggregate reductions of Medicare payments to providers of up to 2% per fiscal year, which went into effect on April 1, 2013 and will remain in effect through 2024 unless additional Congressional action is taken. On January 2, 2013, President Obama signed into law the American Taxpayer Relief Act of 2012, or the ATRA, which, among other things, further reduced Medicare payments to certain providers, including physicians, hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years. Celladon expects that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for any product candidates Celladon seeks to develop or additional pricing pressures.

Risks Related to Celladon’s Business Operations

Celladon is the subject of securities class action lawsuits, and additional securities litigation may be brought against it in the future.

In July 2015, following Celladon’s announcements of the negative CUPID 2 data and the suspension of further research and development activities and the subsequent declines of the price of its common stock, three putative

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class actions were filed in the U.S. District Court for the Southern District of California against Celladon and certain of its current and former officers. The complaints generally allege that the defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, by making materially false and misleading statements regarding the clinical trial program for MYDICAR, thereby artificially inflating the price of Celladon’s common stock. The complaints seek unspecified monetary damages and other relief, including attorneys’ fees. On September 1, 2015, six stockholders (or groups of stockholders) filed motions to consolidate the three putative securities class actions and to appoint lead plaintiffs (the “Motions to Consolidate”). A hearing on the Motions to Consolidate was held on December 3, 2015. On December 9, 2015, the Court consolidated the three putative securities class actions and appointed a lead plaintiff to represent the putative class. Celladon expects the lead plaintiff to file a consolidated complaint. It is possible that additional suits will be filed, or allegations made by stockholders, with respect to these same or other matters and also naming Celladon and/or its officers and directors as defendants. Celladon believes that it has meritorious defenses and intends to defend these lawsuits vigorously. Due to the early stage of these proceedings, Celladon is not able to predict or reasonably estimate the ultimate outcome or possible losses relating to these claims. While Celladon has directors’ and officers’ liability insurance, there is no assurance that the coverage will be sufficient. In addition, any such litigation could result in substantial costs and a diversion of management’s attention and resources, which could harm its business.

Celladon’s employees, principal investigators, consultants and commercial partners may engage in misconduct or other improper activities, including non-compliance with regulatory standards and requirements and insider trading.

Celladon is exposed to the risk of fraudulent conduct or other illegal activity by its employees, independent contractors, principal investigators, consultants, commercial partners and vendors. Misconduct by these parties could include intentional, reckless and/or negligent conduct that fails to: comply with the regulations of the FDA and non-U.S. regulators, provide accurate information to the FDA and non-U.S. regulators, comply with healthcare fraud and abuse laws in the United States and abroad, report financial information or data accurately or disclose unauthorized activities to Celladon. In particular, promotion, sales, marketing and certain business arrangements in the healthcare industry are subject to extensive laws intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Such misconduct could also involve the improper use of information obtained in the course of patient recruitment or clinical trials, which could result in regulatory sanctions and cause serious harm to Celladon’s reputation. Celladon has adopted a code of business conduct and ethics applicable to all of its employees, but it is not always possible to identify and deter employee misconduct, and the precautions Celladon takes to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting it from governmental investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. If any such actions are instituted against Celladon, and it is not successful in defending itself or asserting its rights, those actions could have a significant impact on its business, including the imposition of significant fines or other sanctions.

Celladon faces potential product liability, and, if successful claims are brought against it, it may incur substantial liability and costs. If the use or misuse of Celladon’s product candidates harms patients, or is perceived to harm patients even when such harm is unrelated to its product candidates, its regulatory approvals could be revoked or otherwise negatively impacted and it could be subject to costly and damaging product liability claims.

The use or misuse of Celladon’s product candidates in clinical trials and the sale of any products for which it obtains marketing approval exposes Celladon to the risk of product liability claims. Product liability claims might be brought against Celladon by consumers, healthcare providers, pharmaceutical companies or others selling or otherwise coming into contact with its products. There is a risk that its product candidates may induce adverse

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events. If Celladon cannot successfully defend against product liability claims, it could incur substantial liability and costs. In addition, regardless of merit or eventual outcome, product liability claims may result in:

Celladon carries product liability insurance of $10.0 million per occurrence and a $10.0 million aggregate limit. Celladon believes its product liability insurance coverage is appropriate in light of its current clinical programs; however, it may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect itself against losses due to liability. If and when Celladon obtains marketing approval for product candidates, it intends to expand its insurance coverage to include the sale of commercial products; however, it may be unable to obtain product liability insurance on commercially reasonable terms or in adequate amounts. On occasion, large judgments have been awarded in class action lawsuits based on drugs or medical treatments that had unanticipated adverse effects. A successful product liability claim or series of claims brought against Celladon could cause its stock price to decline and, if judgments exceed its insurance coverage, could adversely affect its results of operations and business.

Patients with the diseases targeted by Celladon’s product candidates are often already in severe and advanced stages of disease and have both known and unknown significant pre-existing and potentially life-threatening health risks. During the course of treatment, patients may suffer adverse events, including death, for reasons that may or may not be related to its product candidates. Such events could subject Celladon to costly litigation, require it to pay substantial amounts of money to injured patients, delay, negatively impact or end its opportunity to receive or maintain regulatory approval to market its products, or require it to suspend or abandon its commercialization efforts. Even in a circumstance in which Celladon does not believe that an adverse event is related to its products, the investigation into the circumstance may be time-consuming or inconclusive. These investigations may interrupt its sales efforts, delay its regulatory approval process in other countries, or impact and limit the type of regulatory approvals its product candidates receive or maintain. As a result of these factors, a product liability claim, even if successfully defended, could have a material adverse effect on its business, financial condition or results of operations.

Celladon may not be successful in identifying or discovering additional product candidates.

Celladon’s research programs, if resumed, may fail to identify other potential product candidates for clinical development for a number of reasons. For example, Celladon’s research methodology may be unsuccessful in identifying potential product candidates or its potential product candidates may be shown to have harmful side effects or may have other characteristics that may make the products unmarketable or unlikely to receive marketing approval.

If any of these events occur, Celladon may be forced to abandon its development efforts for a program or programs, which may have a material adverse effect on its business and could potentially cause Celladon to cease operations. Research programs to identify new product candidates require substantial technical, financial and human resources. Celladon may focus its efforts and resources on potential programs or product candidates that ultimately prove to be unsuccessful.

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Unfavorable global economic conditions could adversely affect Celladon’s business, financial condition or results of operations.

Celladon’s results of operations could be adversely affected by general conditions in the global economy and in the global financial markets. The recent global financial crisis caused extreme volatility and disruptions in the capital and credit markets. A severe or prolonged economic downturn, such as the recent global financial crisis, could result in a variety of risks to Celladon’s business, including, weakened demand for its product candidates and a decreased ability to raise additional capital when needed on acceptable terms, if at all. This is particularly true in Europe, which is undergoing a continued severe economic crisis. A weak or declining economy could also strain Celladon’s suppliers, possibly resulting in supply disruption, or cause its customers to delay making payments for its services. Any of the foregoing could harm Celladon’s business and it cannot anticipate all of the ways in which the current economic climate and financial market conditions could adversely impact its business.

Celladon’s business and operations would suffer in the event of system failures.

Despite the implementation of security measures, Celladon’s internal computer systems and those of its current and any future contract research organizations, or CROs, and other contractors, consultants and potential collaborators are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. While Celladon has not experienced any such material system failure, accident or security breach to date, if such an event were to occur and cause interruptions in its operations, it could result in a material disruption of its development programs and its business operations. For example, the loss of clinical trial data from completed or future clinical trials could result in delays in regulatory approval efforts and significantly increase Celladon’s costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of, or damage to, Celladon’s data or applications, or inappropriate disclosure of confidential or proprietary information, Celladon could incur liability and the further development and commercialization of product candidates could be delayed.

Interruptions in the supply of product or inventory loss may adversely affect Celladon’s operating results and financial condition.

Many product candidates are manufactured and distributed using technically complex processes requiring specialized facilities, highly specific raw materials and other production constraints. The complexity of these processes, as well as strict company and government standards for the manufacture and storage of Celladon’s products, subjects Celladon to production risks. While product batches released for use in clinical trials or for commercialization undergo sample testing, some defects may only be identified following product release. In addition, process deviations or unanticipated effects of approved process changes may result in these intermediate products not complying with stability requirements or specifications. Most of Celladon’s product candidates must be stored and transported at temperatures within a certain range. If these environmental conditions deviate, Celladon’s product candidates’ remaining shelf-lives could be impaired or their efficacy and safety could become adversely affected, making them no longer suitable for use. The occurrence or suspected occurrence of production and distribution difficulties can lead to lost inventories, and in some cases product recalls, with consequential reputational damage and the risk of product liability. The investigation and remediation of any identified problems can cause production delays, substantial expense, lost sales and delays of new product launches. Any interruption in the supply of finished products or the loss thereof could hinder Celladon’s ability to timely distribute its products and satisfy customer demand. Any unforeseen failure in the storage of the product or loss in supply could delay its clinical trials and, if its product candidates are approved, result in a loss of its market share and negatively affect its revenues and operations.

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Celladon or the third parties upon whom it depends may be adversely affected by earthquakes or other natural disasters and its business continuity and disaster recovery plans may not adequately protect Celladon from a serious disaster.

Earthquakes or other natural disasters could severely disrupt Celladon’s operations, and have a material adverse effect on its business, results of operations, financial condition and prospects. A majority of Celladon’s management operates in its principal executive offices located in San Diego, California. If Celladon’s San Diego offices were affected by a natural or man-made disaster, particularly those that are characteristic of the region, such as wildfires and earthquakes, or other business interruption, its ability to manage its domestic and foreign operations could be impaired, which could materially and adversely affect its results of operations and financial condition. If a natural disaster, power outage or other event occurred that prevented Celladon from using all or a significant portion of its headquarters, that damaged critical infrastructure, such as the manufacturing facilities of Celladon’s third-party contract manufacturers, or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible for Celladon to continue its business for a substantial period of time. The disaster recovery and business continuity plans Celladon has in place currently are limited and are unlikely to prove adequate in the event of a serious disaster or similar event. Celladon may incur substantial expenses as a result of the limited nature of its disaster recovery and business continuity plans, which, particularly when taken together with its lack of earthquake insurance, could have a material adverse effect on its business.

Risks Related to Celladon’s Intellectual Property

If Celladon is unable to obtain or protect intellectual property rights related to any future product candidates, Celladon may not be able to compete effectively in its markets.

Biotechnology companies typically rely upon a combination of patents, trade secret protection and confidentiality agreements to protect the intellectual property related to product candidates. The strength of patents in the biotechnology and pharmaceutical field involves complex legal and scientific questions and can be uncertain. The patent applications that Celladon owns or in-licenses may fail to result in issued patents with claims that cover its product candidates in the United States or in other foreign countries. There is no assurance that all of the potentially relevant prior art relating to Celladon’s patents and patent applications will be found, which can invalidate a patent or prevent a patent from issuing from a pending patent application. Even if patents do successfully issue and even if such patents cover Celladon’s product candidates, third parties may challenge their validity, enforceability or scope, which may result in such patents being narrowed or invalidated. Furthermore, even if they are unchallenged, Celladon’s patents and patent applications may not adequately protect its intellectual property, provide exclusivity for its product candidates or prevent others from designing around its claims.

If the patent applications Celladon holds or in-licenses with respect to its programs and product candidates fail to issue, if their breadth or strength of protection is threatened, or if they fail to provide meaningful exclusivity for Celladon’s product candidates, it could dissuade companies from collaborating with Celladon to develop product candidates, and threaten Celladon’s ability to commercialize future products. Celladon cannot offer any assurances about which, if any, patents will issue, the breadth of any such patent or whether any issued patents will be found invalid and unenforceable or will be threatened by third parties. Any successful opposition to patents owned by or licensed to Celladon could deprive it of rights necessary for the successful commercialization of any product candidates that it may develop. Further, if it encounters delays in regulatory approvals, the period of time during which Celladon could market a product candidate under patent protection could be reduced. Since patent applications in the United States and most other countries are confidential for a period of time after filing, and some remain so until issued, Celladon cannot be certain that it was the first to file any patent application related to a product candidate. Furthermore, if third parties have filed such patent applications, an interference proceeding in the United States can be initiated by a third party to determine who was the first to invent any of the subject matter covered by the patent claims of Celladon’s applications. In addition, patents have a limited lifespan. In the United States, the natural expiration of a patent is generally 20 years after it is filed. Various extensions may be available; however the life of a patent, and the protection it

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affords, is limited. Even if patents covering Celladon’s product candidates are obtained, once the patent life has expired for a product, Celladon may be open to competition from generic medications.

In addition to the protection afforded by patents, Celladon relies on trade secret protection and confidentiality agreements to protect proprietary know-how that is not patentable or that it elects not to patent, processes for which patents are difficult to enforce and any other elements of its product candidates discovery and development processes that involve proprietary know-how, information or technology that is not covered by patents. However, trade secrets can be difficult to protect. Celladon seeks to protect its proprietary technology and processes, in part, by entering into confidentiality agreements with those who have access to its confidential information, including employees, consultants, scientific advisors and contractors. Celladon also seeks to preserve the integrity and confidentiality of its data and trade secrets by maintaining physical security of its premises and physical and electronic security of its information technology systems. While Celladon has confidence in these individuals, organizations and systems, agreements or security measures may be breached, and Celladon may not have adequate remedies for any breach. In addition, Celladon’s trade secrets may otherwise become known or be independently discovered by competitors.

Although Celladon expects all of its employees and consultants to assign their inventions to Celladon, and all of its employees, consultants, advisors and any third parties who have access to its proprietary know-how, information or technology to enter into confidentiality agreements, Celladon cannot provide any assurances that all such agreements have been duly executed or that its trade secrets and other confidential proprietary information will not be disclosed or that competitors will not otherwise gain access to its trade secrets or independently develop substantially equivalent information and techniques. Misappropriation or unauthorized disclosure of Celladon’s trade secrets could impair its competitive position and may have a material adverse effect on its business. Additionally, if the steps taken to maintain its trade secrets are deemed inadequate, Celladon may have insufficient recourse against third parties for misappropriating the trade secret. In addition, others may independently discover Celladon’s trade secrets and proprietary information. For example, the FDA, as part of its Transparency Initiative, is currently considering whether to make additional information publicly available on a routine basis, including information that Celladon may consider to be trade secrets or other proprietary information, and it is not clear at the present time how the FDA’s disclosure policies may change in the future, if at all. Further, the laws of some foreign countries do not protect proprietary rights to the same extent or in the same manner as the laws of the United States. As a result, Celladon may encounter significant problems in protecting and defending its intellectual property both in the United States and abroad. If Celladon is unable to prevent material disclosure of the non-patented intellectual property related to its technologies to third parties, and there is no guarantee that Celladon will have any such enforceable trade secret protection, Celladon may not be able to establish or maintain a competitive advantage in its market, which could materially adversely affect its business, results of operations and financial condition.

Third-party claims of intellectual property infringement may prevent or delay Celladon’s development and commercialization efforts.

Celladon’s commercial success depends in part on avoiding infringement of the patents and proprietary rights of third parties. There is a substantial amount of litigation, both within and outside the United States, involving patent and other intellectual property rights in the biotechnology and pharmaceutical industries, including patent infringement lawsuits, interferences, oppositions and inter partes review proceedings before the U.S. Patent and Trademark Office, or U.S. PTO, and corresponding foreign patent offices. Numerous U.S. and foreign issued patents and pending patent applications, which are owned by third parties, exist in the fields in which Celladon is pursuing development candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that Celladon’s product candidates may be subject to claims of infringement of the patent rights of third parties.

Third parties may assert that Celladon is employing their proprietary technology without authorization. There may be third-party patents or patent applications with claims to materials, formulations, methods of manufacture

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or methods for treatment related to the use or manufacture of its product candidates. Because patent applications can take many years to issue, third parties may have currently pending patent applications which may later result in issued patents that Celladon’s product candidates may infringe, or which such third parties claim are infringed by the use of Celladon’s technologies. If any third-party patents are held by a court of competent jurisdiction to cover any aspect of the manufacturing process for any of Celladon’s product candidates, any molecules formed during the manufacturing process, or any final product candidate, including the formulation or method of use of such product candidate, the holders of any such patents may be able to block Celladon’s ability to commercialize such product candidate unless Celladon obtained a license under the applicable patents, or until such patents expire. In any such case, such a license may not be available on commercially reasonable terms or at all.

Parties making claims against Celladon for infringement of their intellectual property rights may obtain injunctive or other equitable relief, which could effectively block Celladon’s ability to further develop and commercialize one or more of its product candidates. Defense of these claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of employee resources from Celladon’s business. In the event of a successful claim of infringement against Celladon, it could be required to redesign its infringing products or obtain a license from such third party to continue developing and commercializing its products and technology. However, Celladon may not be able to obtain any required license on commercially reasonable terms, or at all. Even if Celladon is able to obtain a license, it may be non-exclusive, thereby giving its competitors access to the same technologies licensed to Celladon. It may be impossible to redesign Celladon’s products and technology, or it may require substantial time and monetary expenditure, which could force Celladon to cease commercialization of one or more of its product candidates, or some of its business operations, which could materially harm its business. In addition, in any such proceeding, Celladon may be required to pay substantial damages, including treble damages and attorneys’ fees in the event Celladon is found liable for willful infringement.

Recent patent reform legislation could increase the uncertainties and costs surrounding the prosecution of Celladon’s patent applications and the enforcement or defense of its issued patents.

In September 2011, the Leahy-Smith America Invents Act, or the Leahy-Smith Act, was signed into law. The Leahy-Smith Act includes a number of significant changes to U.S. patent law, including provisions that affect the way patent applications will be prosecuted and may also affect patent litigation. The U.S. PTO is currently developing regulations and procedures to govern administration of the Leahy-Smith Act, and many of the substantive changes to patent law associated with the Leahy-Smith Act, and in particular, the first to file provisions, were enacted in March 2013. It is not clear what, if any, impact the Leahy-Smith Act will have on the operation of Celladon’s business. Moreover, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of Celladon’s patent applications and the enforcement or defense of its issued patents, all of which could have a material adverse effect on Celladon’s business and financial condition.

Celladon may be subject to claims that its employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties or that Celladon’s employees have wrongfully used or disclosed alleged trade secrets of their former employers.

Although Celladon seeks to protect its ownership of intellectual property rights by ensuring that its agreements with its employees, collaborators and other third parties with whom it does business include provisions requiring such parties to assign rights in inventions to Celladon, Celladon may also be subject to claims that former employees, collaborators or other third parties have an ownership interest in its patents or other intellectual property. Celladon may be subject to ownership disputes in the future arising, for example, from conflicting obligations of consultants or others who are involved in developing its product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship or ownership. If Celladon fails in defending any such claims, in addition to paying monetary damages, Celladon may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Such an outcome

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could have a material adverse effect on Celladon’s business. Even if Celladon is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Celladon may be subject to claims challenging the inventorship or ownership of its patents and other intellectual property.

Celladon may also be subject to claims that former employees, collaborators or other third parties have an ownership interest in its patents or other intellectual property. Celladon may be subject to ownership disputes in the future arising, for example, from conflicting obligations of consultants or others who are involved in developing its product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship or ownership. If Celladon fails in defending any such claims, in addition to paying monetary damages, Celladon may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Such an outcome could have a material adverse effect on Celladon’s business. Even if Celladon is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Obtaining and maintaining Celladon’s patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and Celladon’s patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and/or applications will be due to be paid to the U.S. PTO and various governmental patent agencies outside of the United States in several stages over the lifetime of the patents and/or applications. Celladon has systems in place to remind it to pay these fees, and it employs an outside firm and relies on its outside counsel to pay these fees due to non-U.S. patent agencies. The U.S. PTO and various non-U.S. governmental patent agencies require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. Celladon employs reputable law firms and other professionals to help it comply, and in many cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with the applicable rules. However, there are situations in which non-compliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. In such an event, Celladon’s competitors might be able to enter the market and this circumstance would have a material adverse effect on its business.

Risks Related to Ownership of Celladon’s Common Stock

The market price of Celladon’s common stock may continue to be highly volatile, and you may not be able to resell some or all of your shares at a desired market price.

The market price of Celladon’s common stock has been and is likely to continue to be volatile. Since Celladon’s initial public offering in January 2014 at a price of $8.00 per share, the sale price of stock as reported on The NASDAQ Global Market has ranged from $1.00 to $28.25, through December 11, 2015. Celladon’s stock price could be subject to wide fluctuations in response to a variety of factors, including the following:

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In addition, companies trading in the stock market in general, and the NASDAQ Global Market in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of Celladon’s common stock, regardless of its actual operating performance.

If securities or industry analysts issue an adverse or misleading opinion regarding Celladon’s stock, Celladon’s stock price and trading volume could decline.

The trading market for Celladon’s common stock will be influenced by the research and reports that industry or securities analysts publish about Celladon or its business. If any of the analysts who cover Celladon issue an adverse or misleading opinion regarding Celladon, its business model, its intellectual property or its stock performance, or if Celladon’s clinical trials and operating results fail to meet the expectations of analysts, its stock price would likely decline. If one or more of these analysts cease coverage of Celladon or fail to publish reports on it regularly, Celladon could lose visibility in the financial markets, which in turn could cause its stock price or trading volume to decline.

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Celladon is an “emerging growth company,” and cannot be certain if the reduced reporting requirements applicable to emerging growth companies will make its common stock less attractive to investors.

Celladon is an “emerging growth company,” as defined in the JOBS Act. For as long as Celladon continues to be an emerging growth company, it may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not “emerging growth companies,” including exemption from compliance with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002 (Sarbanes-Oxley Act), reduced disclosure obligations regarding executive compensation in its periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation. Celladon will remain an emerging growth company until the earlier of (1) the last day of the fiscal year (a) following the fifth anniversary of the completion of its initial public offering, (b) in which it has total annual gross revenue of at least $1.0 billion, or (c) in which it is deemed to be a large accelerated filer, which means the market value of Celladon’s common stock that is held by non-affiliates exceeded $700.0 million as of the prior June 30th, and (2) the date on which Celladon has issued more than $1.0 billion in non-convertible debt during the prior three-year period.

Under the JOBS Act, emerging growth companies can also delay adopting new or revised accounting standards until such time as those standards apply to private companies. Celladon has irrevocably elected not to avail itself of this exemption from new or revised accounting standards and, therefore, will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.

Celladon’s quarterly operating results may fluctuate significantly or may fall below the expectations of investors or securities analysts, each of which may cause its stock price to fluctuate or decline.

Celladon expects its operating results to be subject to quarterly fluctuations. Celladon’s net loss and other operating results will be affected by numerous factors, including:

If Celladon’s quarterly operating results fall below the expectations of investors or securities analysts, the price of its common stock could decline substantially. Furthermore, any quarterly fluctuations in its operating results may, in turn, cause the price of its stock to fluctuate substantially. Celladon believes that quarterly comparisons of its financial results are not necessarily meaningful and should not be relied upon as an indication of its future performance.

If Celladon fails to maintain an effective system of internal control over financial reporting, it may not be able to accurately report its financial results or prevent fraud. As a result, stockholders could lose confidence in its financial and other public reporting, which would harm its business and the trading price of its common stock.

Effective internal controls over financial reporting are necessary for Celladon to provide reliable financial reports and, together with adequate disclosure controls and procedures, are designed to prevent fraud. Any failure to

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implement required new or improved controls, or difficulties encountered in their implementation could cause Celladon to fail to meet its reporting obligations. In addition, any testing by Celladon conducted in connection with Section 404 of the Sarbanes-Oxley Act, or the subsequent testing by Celladon’s independent registered public accounting firm, may reveal deficiencies in its internal controls over financial reporting that are deemed to be material weaknesses or that may require prospective or retroactive changes to its consolidated financial statements or identify other areas for further attention or improvement. Inferior internal controls could also cause investors to lose confidence in Celladon’s reported financial information, which could have a negative effect on the trading price of its common stock.

Sales of a substantial number of shares of Celladon’s common stock in the public market could cause its stock price to fall.

Sales of a substantial number of shares of Celladon’s common stock in the public market or the perception that these sales might occur, could depress the market price of Celladon’s common stock and could impair its ability to raise capital through the sale of additional equity securities. Celladon is unable to predict the effect that sales may have on the prevailing market price of its common stock.

Certain holders of Celladon’s securities are entitled to rights with respect to the registration of their shares under the Securities Act. Registration of these shares under the Securities Act would result in the shares becoming freely tradable without restriction under the Securities Act, except for shares held by Celladon’s affiliates as defined in Rule 144 under the Securities Act. Any sales of securities by these stockholders could have a material adverse effect on the trading price of Celladon’s common stock.

Future sales and issuances of Celladon’s common stock or rights to purchase common stock, including pursuant to its equity incentive plans, could result in additional dilution of the percentage ownership of Celladon’s stockholders and could cause its stock price to fall.

Celladon expects that significant additional capital will be needed in the future to continue operations, should it decide to continue its historical business operations. To the extent Celladon raises additional capital by issuing equity securities, its stockholders may experience substantial dilution. Celladon may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner it determines from time to time. If Celladon sells common stock, convertible securities or other equity securities in more than one transaction, investors may be materially diluted by subsequent sales. These sales may also result in material dilution to its existing stockholders, and new investors could gain rights superior to existing stockholders.

Pursuant to Celladon’s 2013 equity incentive plan, or the 2013 plan, Celladon’s management is authorized to grant stock options and other equity-based awards to its employees, directors and consultants. The number of shares available for future grant under the 2013 plan will automatically increase on January 1 of each year by 5% of the total number of shares of Celladon’s common stock outstanding on December 31 of the preceding calendar year, subject to the ability of Celladon’s board of directors to take action to reduce the size of the increase in any given year. In addition, Celladon may grant or provide for the grant of rights to purchase shares of its common stock pursuant to its 2013 employee stock purchase plan, or ESPP. The number of shares of Celladon’s common stock reserved for issuance under the ESPP will automatically increase on January 1 of each calendar year by the lesser of 1% of the total number of shares of its common stock outstanding on December 31 of the preceding calendar year and 384,307 shares, subject to the ability of Celladon’s board of directors to take action to reduce the size of the increase in any given year. Currently, Celladon plans to register the increased number of shares available for issuance under the 2013 plan and ESPP each year. Increases in the number of shares available for future grant or purchase may result in additional dilution, which could cause Celladon’s stock price to decline. In addition, Celladon has in the past and may in the future grant inducement grants to prospective employees and consultants, which may result in further dilution and cause Celladon’s stock price to decline.

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Celladon does not intend to pay dividends on its common stock so any returns will be limited to the value of its stock.

Celladon has never declared or paid any cash dividends on its common stock. Celladon currently anticipates that it will retain future earnings for the development, operation and expansion of its business and does not anticipate declaring or paying any cash dividends for the foreseeable future. In addition, Celladon’s ability to pay dividends is currently restricted by the terms of its loan agreement with Hercules. Any return to stockholders will therefore be limited to the appreciation of their stock.

Provisions in Celladon’s amended and restated certificate of incorporation and bylaws, as well as provisions of Delaware law, could make it more difficult for a third party to acquire Celladon or increase the cost of acquiring it, even if doing so would benefit Celladon’s stockholders or remove its current management.

Some provisions of Celladon’s charter documents and Delaware law may have anti-takeover effects that could discourage an acquisition of Celladon by others, even if an acquisition would be beneficial to its stockholders and may prevent attempts by Celladon’s stockholders to replace or remove current management. These provisions include:

These provisions may frustrate or prevent any attempts by Celladon’s stockholders to replace or remove current management by making it more difficult for stockholders to replace members of the board of directors, which is responsible for appointing the members of management. In addition, Celladon is subject to Section 203 of the Delaware General Corporation Law, which generally prohibits a Delaware corporation from engaging in any of a broad range of business combinations with an interested stockholder for a period of three years following the date on which the stockholder became an interested stockholder, unless such transactions are approved by Celladon’s board of directors. This provision could have the effect of delaying or preventing a change of control, whether or not it is desired by or beneficial to Celladon’s stockholders. Further, other provisions of Delaware law may also discourage, delay or prevent someone from acquiring Celladon or merging with it.

Risks Related to Eiger’s Financial Condition and Capital Requirements

Eiger has incurred losses since its inception, has a limited operating history on which to assess its business, and anticipates that it will continue to incur significant losses for the foreseeable future.

Eiger is a clinical development-stage biopharmaceutical company with a limited operating history. Eiger has incurred net losses in each year since its inception in 2008, including net losses of $1.5 million and $1.0 million for the years ended December 31, 2014 and 2013, respectively, and $6.3 million for the nine months ended September 30, 2015. As of September 30, 2015, Eiger had an accumulated deficit of $22.2 million.

The audit report on Eiger’s consolidated financial statements for the year ended December 31, 2014, which appears elsewhere herein, includes an explanatory paragraph related to Eiger’s ability to continue as a going concern. As of September 30, 2015, Eiger had cash of $2.1 million. In November 2015, Eiger received

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$6.0 million in financing under bridge promissory notes which is due and payable on March 31, 2016. Eiger’s current capital resources, if the transactions contemplated by this proxy statement/prospectus/information statement are not completed, are insufficient to fund its planned operations for a 12-month period, and therefore, raise substantial doubt about its ability to continue as a going concern. Eiger will continue to require substantial additional capital to continue its clinical development and potential commercialization activities. Accordingly, Eiger will need to raise substantial additional capital to continue to fund its operations. The amount and timing of its future funding requirements will depend on many factors, including the pace and results of its clinical development efforts. Failure to raise capital as and when needed, on favorable terms or at all, would have a negative impact on its financial condition and its ability to develop its product candidates.

Eiger has devoted substantially all of its financial resources to identify, acquire, and develop its product candidates, including conducting clinical studies and providing general and administrative support for its operations. To date, Eiger has financed its operations primarily through the sale of equity securities and convertible promissory notes. The amount of its future net losses will depend, in part, on the rate of its future expenditures and its ability to obtain funding through equity or debt financings, strategic collaborations, or grants. Biopharmaceutical product development is a highly speculative undertaking and involves a substantial degree of risk. Eiger expects losses to increase as it advances three clinical candidates into Phase 2 development for potentially four indications. While Eiger has not yet commenced pivotal clinical studies for any product candidate and it may be several years, if ever, before Eiger completes pivotal clinical studies and has a product candidate approved for commercialization, Eiger expects to invest significant funds into these clinical candidates to determine the potential to advance these compounds to regulatory approval.

If Eiger obtains regulatory approval to market a product candidate, its future revenue will depend upon the size of any markets in which its product candidates may receive approval, and its ability to achieve sufficient market acceptance, pricing, reimbursement from third-party payors, and adequate market share for its product candidates in those markets. Even if Eiger obtains adequate market share for its product candidates, because the potential markets in which its product candidates may ultimately receive regulatory approval could be very small, Eiger may never become profitable despite obtaining such market share and acceptance of its products.

Eiger expects to continue to incur significant expenses and increasing operating losses for the foreseeable future and its expenses will increase substantially if and as Eiger:

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Further, the net losses Eiger incurs may fluctuate significantly from quarter to quarter and year to year, such that a period-to-period comparison of its results of operations may not be a good indication of its future performance.

Eiger has never generated any revenue from product sales and may never be profitable.

Eiger has no products approved for commercialization and has never generated any revenue. Eiger’s ability to generate revenue and achieve profitability depends on its ability, alone or with strategic collaboration partners, to successfully complete the development of, and obtain the regulatory and marketing approvals necessary to commercialize one or more of its product candidates. Eiger does not anticipate generating revenue from product sales for the foreseeable future. Eiger’s ability to generate future revenue from product sales depends heavily on its success in many areas, including but not limited to:

Even if one or more of the product candidates that Eiger develops is approved for commercial sale, Eiger anticipates incurring significant costs associated with commercializing any approved product candidate. Its current pipeline of product candidates has been in-licensed from third parties and Eiger will have to develop or acquire manufacturing capabilities in order to continue development and potential commercialization of its product candidates. Additionally, if Eiger is not able to generate revenue from the sale of any approved products, Eiger may never become profitable.

Raising additional capital may cause dilution to Eiger’s stockholders, restrict its operations or require Eiger to relinquish rights.

To the extent that Eiger raises additional capital through the sale of equity, debt or other securities convertible into equity, your ownership interest will be diluted, and the terms of these new securities may include liquidation or other preferences that adversely affect your rights as a common stockholder. Debt financing, if available at all, would likely involve agreements that include covenants limiting or restricting Eiger’s ability to take specific actions, such as incurring additional debt, making capital expenditures, making additional product acquisitions, or declaring dividends. If Eiger raises additional funds through collaborations, strategic alliances or licensing arrangements with third parties, Eiger may have to relinquish valuable rights to its product candidates or future

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revenue streams or grant licenses on terms that are not favorable to Eiger. Eiger cannot assure you that it will be able to obtain additional funding if and when necessary to fund its entire portfolio of product candidates to meet its projected plans. If Eiger is unable to obtain funding on a timely basis, Eiger may be required to delay or discontinue one or more of its development programs or the commercialization of any product candidates or be unable to expand its operations or otherwise capitalize on potential business opportunities, which could materially affect Eiger’s business, financial condition, and results of operations.

Risks Related to the Development of Eiger’s Product Candidates

Eiger is heavily dependent on the success of its product candidates, which are in the early stages of clinical development. Certain of its product candidates have produced results in academic settings to date or for other indications than those that Eiger contemplates and Eiger cannot give any assurance that it will generate data for any of its product candidates sufficient to receive regulatory approval in its planned indications, which will be required before they can be commercialized.

To date, Eiger has invested substantially all of its efforts and financial resources to identify, acquire, and develop its portfolio of product candidates. Its future success is dependent on its ability to successfully further develop, obtain regulatory approval for, and commercialize one or more product candidates. Eiger currently generates no revenue from sales of any drugs, and Eiger may never be able to develop or commercialize a product candidate.

Eiger currently has three product candidates in or ready for four Phase 1/2 or Phase 2 clinical studies. One of the Eiger product candidates, exendin (9-39) has only generated data in an academic setting and Eiger may not be able to replicate or develop additional data to satisfy regulatory requirements for approval. For ubenimex, data to date has been developed for use in indications other than those that Eiger has rights to or in which Eiger plans to develop the product candidate. There can be no assurance that the data that Eiger develops for its product candidates in its planned indications will be sufficient to obtain regulatory approval.

In addition, none of its product candidates have advanced into a pivotal study for Eiger’s proposed indications and it may be years before such study is initiated and completed, if at all. Eiger is not permitted to market or promote any of its product candidates before it receives regulatory approval from the FDA or comparable foreign regulatory authorities, and Eiger may never receive such regulatory approval for any of its product candidates. Eiger cannot be certain that any of its product candidates will be successful in clinical studies or receive regulatory approval. Further, its product candidates may not receive regulatory approval even if they are successful in clinical studies. If Eiger does not receive regulatory approvals for its product candidates, Eiger may not be able to continue its operations.

Eiger’s business strategy is based upon obtaining orphan drug designation for its product candidates, which is an uncertain process. The regulatory approval processes of the FDA and comparable foreign authorities are lengthy, time consuming, and inherently unpredictable. If Eiger is unable to obtain orphan drug designation or regulatory approval for its product candidates, its business will be substantially harmed.

Eiger’s approach to identifying and developing product candidates depends, in large part, on its ability to obtain orphan drug designation from regulatory authorities in major markets. Without the protection of this regulatory exclusivity, many of its product candidates would otherwise not justify investment as they are not protected by patents or they are otherwise marketed or generic products. While Eiger assesses the potential for obtaining orphan drug designation at the time that Eiger contemplates the acquisition of product candidates and Eiger intends to timely file for such designation, there can be no assurance that Eiger will obtain orphan drug designation or be able to successfully meet the regulatory requirements to maintain that designation with the planned clinical trials for its product candidates. Failure to obtain orphan drug designation would make its product candidates significantly less competitive and potentially not viable investments for further development.

The time required to obtain approval by the FDA and comparable foreign authorities is unpredictable, typically takes many years following the commencement of clinical studies, and depends upon numerous factors. In

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addition, approval policies, regulations, or the type and amount of clinical data necessary to gain approval may change during the course of a product candidate’s clinical development and may vary among jurisdictions, which may cause delays in the approval or the decision not to approve an application. Eiger has not obtained regulatory approval for any product candidate, and it is possible that none of its existing product candidates or any product candidates Eiger may seek to develop in the future will ever obtain regulatory approval.

Applications for Eiger’s product candidates could fail to receive regulatory approval for many reasons, including but not limited to the following:

The lengthy and uncertain regulatory approval process, as well as the unpredictability of the results of clinical studies, may result in Eiger’s failing to obtain regulatory approval to market any of its product candidates, which would significantly harm its business, results of operations, and prospects. In addition, although Eiger has obtained orphan drug designation for two of its product candidates in its planned indications to date, there can be no assurance that the FDA will grant Eiger’s similar status for its other proposed development indications or other product candidates in the future.

Drug development involves a lengthy and expensive process with an uncertain outcome, and results of earlier studies may not be predictive of future study results.

Clinical testing is expensive and generally takes many years to complete, and the outcome is inherently uncertain. Failure can occur at any time during the clinical study process. The results of preclinical studies and early clinical studies of Eiger’s product candidates may not be predictive of the results of larger, later-stage controlled clinical studies. Product candidates that have shown promising results in early-stage clinical studies may still suffer significant setbacks in subsequent clinical studies. Eiger’s clinical studies to date have been conducted on a small number of patients in limited numbers of clinical sites and in academic settings or for other indications. Eiger will have to conduct larger, well-controlled studies in its proposed indications to verify the results obtained to date and to support any regulatory submissions for further clinical development. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical studies due to lack of efficacy or adverse safety profiles despite promising results in earlier, smaller clinical studies. Moreover, clinical data are often susceptible to varying interpretations and analyses. Eiger does not know whether any Phase 2, Phase 3, or other clinical studies Eiger may conduct will demonstrate consistent or adequate efficacy and safety with respect to the proposed indication for use sufficient to obtain regulatory approval to receive regulatory approval or market its drug candidates.

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Eiger may find it difficult to enroll patients in its clinical studies given the limited number of patients who have the diseases for which its product candidates are being studied. Difficulty in enrolling patients could delay or prevent clinical studies of its product candidates.

Identifying and qualifying patients to participate in clinical studies of Eiger’s product candidates is essential to its success. The timing of Eiger’s clinical studies depends in part on the rate at which Eiger can recruit patients to participate in clinical trials of its product candidates, and Eiger may experience delays in its clinical studies if Eiger encounters difficulties in enrollment.

The eligibility criteria of Eiger’s planned clinical studies may further limit the available eligible study participants as Eiger expects to require that patients have specific characteristics that Eiger can measure or meet the criteria to assure their conditions are appropriate for inclusion in its clinical studies. Eiger may not be able to identify, recruit, and enroll a sufficient number of patients to complete its clinical studies in a timely because of the perceived risks and benefits of the product candidate under study, the availability and efficacy of competing therapies and clinical studies, and the willingness of physicians to participate in its planned clinical studies. If patients are unwilling to participate in Eiger’s clinical studies for any reason, the timeline for conducting studies and obtaining regulatory approval of its product candidates may be delayed.

If Eiger experiences delays in the completion of, or termination of, any clinical study of its product candidates, the commercial prospects of its product candidates could be harmed, and its ability to generate product revenue from any of these product candidates could be delayed or prevented. In addition, any delays in completing its clinical studies would likely increase its overall costs, impair product candidate development and jeopardize its ability to obtain regulatory approval relative to its current plans. Any of these occurrences may harm its business, financial condition, and prospects significantly.

Clinical studies are costly, time consuming and inherently risky, and Eiger may fail to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities.

Clinical development is expensive, time consuming and involves significant risk. Eiger cannot guarantee that any clinical studies will be conducted as planned or completed on schedule, if at all. A failure of one or more clinical studies can occur at any stage of development. Events that may prevent successful or timely completion of clinical development include but are not limited to:

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Any inability to successfully complete clinical development and obtain regulatory approval could result in additional costs to Eiger or impair its ability to generate revenue. In addition, if Eiger makes manufacturing or formulation changes to its product candidates, such as its plan to manufacture a new subcutaneous formulation of exendin (9-39), Eiger may need to conduct additional studies or the results obtained from such new formulation may not be consistent with previous results obtained. Clinical study delays could also shorten any periods during which its products have patent protection and may allow competitors to develop and bring products to market before Eiger does, which could impair its ability to obtain orphan drug designation exclusivity and to successfully commercialize its product candidates and may harm its business and results of operations.

Eiger’s product candidates may cause undesirable side effects or have other properties that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following marketing approval, if any.

Undesirable side effects caused by its product candidates could cause Eiger or regulatory authorities to interrupt, delay, or terminate clinical studies or even if approved, result in a restrictive label or delay regulatory approval by the FDA or comparable foreign authorities.

In addition, while Eiger’s lonafarnib product candidate has been studied in thousands of oncology patients and the most common non-hematologic adverse events of any grade were gastrointestinal system disorders (nausea, anorexia, diarrhea and vomiting), fatigue and rash, treatment discontinuation across the lonafarnib clinical studies conducted in oncology has been in the range of approximately 20-25% and Eiger may experience comparable or higher rates of discontinuation in testing in its anti-viral, hepatitis D virus studies. There is no guarantee that additional or more severe side effects will not be identified through ongoing clinical studies by other licensees of lonafarnib for other indications or its own clinical trials. Merck & Co., Inc., or Merck, its licensor, has granted rights to develop lonafarnib in progeria, a rare, fatal rapid aging disease, to The Progeria Research Foundation. Additionally, while Eiger has a license to another farnesyltranferase inhibitor compound, tipifarnib, from Janssen Pharmaceutica, N.V., or Janssen, Janssen has granted rights to tipifarnib to Kura Oncology, Inc., or Kura, in oncology (as tipifarnib) and negative results or undesirable side effects from Kura’s clinical trials for a compound with a similar mechanism of action may negatively impact the perception of lonafarnib for anti-viral indications. Merck may also grant rights to other anti-viral or potentially other indications to other third parties. Undesirable side effects and negative results for other indications may negatively impact the development and potential for approval of Eiger’s product candidates for its proposed indications.

Additionally, even if one or more of its product candidates receives marketing approval, and Eiger or others later identify undesirable side effects caused by such products, potentially significant negative consequences could result, including but not limited to:

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Any of these events could prevent Eiger from achieving or maintaining market acceptance of a product candidate, even if approved, and could significantly harm its business, results of operations, and prospects.

Even if Eiger obtains regulatory approval for a product candidate, Eiger will remain subject to ongoing regulatory requirements.

If Eiger’s product candidates are approved, they will be subject to ongoing regulatory requirements with respect to manufacturing, labeling, packaging, storage, advertising, promotion, sampling, record-keeping, conduct of post-marketing studies, and submission of safety, efficacy and other post-approval information, including both federal and state requirements in the United States and requirements of comparable foreign regulatory authorities.

Manufacturers and manufacturers’ facilities are required to continuously comply with FDA and comparable foreign regulatory authority requirements, including ensuring that quality control and manufacturing procedures conform to current Good Manufacturing Practices, or cGMP, regulations and corresponding foreign regulatory manufacturing requirements. As such, Eiger and its contract manufacturers will be subject to continual review and inspections to assess compliance with cGMP and adherence to commitments made in any NDA or marketing authorization application, or MAA.

Any regulatory approvals that Eiger receives for its product candidates may be subject to limitations on the approved indicated uses for which the product candidate may be marketed or to the conditions of approval, or contain requirements for potentially costly post-marketing testing, including Phase IV clinical trials, and surveillance to monitor the safety and efficacy of the product candidate. Eiger will be required to report certain adverse reactions and production problems, if any, to the FDA and comparable foreign regulatory authorities. Any new legislation addressing drug safety issues could result in delays in product development or commercialization, or increased costs to assure compliance. If its original marketing approval for a product candidate was obtained through an accelerated approval pathway, Eiger could be required to conduct a successful post-marketing clinical study in order to confirm the clinical benefit for its products. An unsuccessful post-marketing study or failure to complete such a study could result in the withdrawal of marketing approval.

If a regulatory agency discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency, or problems with the facility where the product is manufactured, or disagrees with the promotion, marketing or labeling of a product, the regulatory agency may impose restrictions on that product or Eiger, including requiring withdrawal of the product from the market. If Eiger fails to comply with applicable regulatory requirements, a regulatory agency or enforcement authority may, among other things:

Any government investigation of alleged violations of law would be expected to require Eiger to expend significant time and resources in response and could generate adverse publicity. Any failure to comply with ongoing regulatory requirements may significantly and adversely affect its ability to develop and commercialize its products and the value of Eiger and its operating results would be adversely affected.

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Eiger relies on third parties to conduct its clinical studies, manufacture its product candidates and perform other services. If these third parties do not successfully perform and comply with regulatory requirements, Eiger may not be able to successfully complete clinical development, obtain regulatory approval or commercialize its product candidates and its business could be substantially harmed.

Eiger has relied upon and plans to continue to rely upon third-party CROs to conduct, monitor and manage its ongoing clinical programs. Eiger relies on these parties for execution of clinical studies and manages and controls only certain aspects of their activities. Eiger remains responsible for ensuring that each of its studies is conducted in accordance with the applicable protocol, legal, regulatory, and scientific standards and its reliance on the CROs does not relieve Eiger of its regulatory responsibilities. Eiger and its CROs and other vendors are required to comply all applicable laws, regulations and guidelines, including those required by the FDA and comparable foreign regulatory authorities for all of its product candidates in clinical development. If Eiger or any of its CROs or vendors fail to comply with applicable laws, regulations and guidelines, the results generated in its clinical studies may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require Eiger to perform additional studies before approving its marketing applications. Eiger cannot assure you that its CROs and other vendors will meet these requirements, or that upon inspection by any regulatory authority, such regulatory authority will determine that efforts, including any of its clinical studies, comply with applicable requirements. Its failure to comply with these laws, regulations and guidelines may require Eiger to repeat clinical studies, which would be costly and delay the regulatory approval process.

If any of Eiger’s relationships with these third-party CROs terminate, Eiger may not be able to enter into arrangements with alternative CROs in a timely manner or do so on commercially reasonable terms. In addition, Eiger’s CROs may not prioritize Eiger’s clinical studies relative to those of other customers and any turnover in personnel or delays in the allocation of CRO employees by the CRO may negatively affect its clinical studies. If CROs do not successfully carry out their contractual duties or obligations or meet expected deadlines, Eiger’s clinical studies may be delayed or terminated and Eiger may not be able to meet its current plans with respect to its product candidates. CROs may also involve higher costs than anticipated, which could negatively affect Eiger’s financial condition and operations.

In addition, Eiger does not currently have, nor does Eiger plan to establish the capability to manufacture product candidates for use in the conduct of its clinical studies, and Eiger lacks the resources and the capability to manufacture any of its product candidates on a clinical or commercial scale without the use of third party manufacturers. Eiger plans to rely on third party manufacturers and their responsibilities will include purchasing from third-party suppliers the materials necessary to produce its product candidates for its clinical studies and regulatory approval. There are expected to be a limited number of suppliers for the active ingredients and other materials that Eiger expects to use to manufacture its product candidates, and Eiger may not be able to identify alternative suppliers to prevent a possible disruption of the manufacture its product candidates for its clinical studies, and, if approved, ultimately for commercial sale. Although Eiger generally does not expect to begin a clinical study unless Eiger believes it has a sufficient supply of a product candidate to complete the study, any significant delay or discontinuity in the supply of a product candidate, or the active ingredient or other material components in the manufacture of the product candidate could delay completion of its clinical studies and potential timing for regulatory approval of its product candidates, which would harm its business and results of operations.

With respect to its lonafarnib and ubenimex product candidates, Eiger relies on Merck and Nippon Kayaku to supply its clinical study materials and Eiger does not have long-term supply agreements or commitments from those parties to supply its materials. Moreover, even if Eiger has a longer term supply arrangement, Eiger may be precluded from entering into a back-up or alternative supplier arrangement which may increase the risk for further development, regulatory approval, or commercialization of its product candidates. Its current agreement with Nippon Kayaku provides for such party to be Eiger’s exclusive supplier for its ubenimex product candidate, which may increase its cost of goods and may not support FDA or other regulatory authority approval for manufacturing.

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Eiger relies and expects to continue to rely on third parties to manufacture its clinical product supplies, and Eiger intends to rely on third parties to produce and process its product candidates, if approved, and Eiger’s commercialization of any of its product candidates could be stopped, delayed or made less profitable if those third parties fail to obtain approval of government regulators, fail to provide Eiger with sufficient quantities of drug product, or fail to do so at acceptable quality levels or prices.

Eiger does not currently have nor does it plan to acquire the infrastructure or capability internally to manufacture its clinical supplies for use in the conduct of Eiger’s clinical trials, and Eiger lacks the resources and the capability to manufacture any of its product candidates on a clinical or commercial scale. Eiger currently relies on outside vendors to manufacture its clinical supplies of its product candidates and plan to continue relying on third parties to manufacture its product candidates on a commercial scale, if approved.

The facilities used by Eiger’s contract manufacturers to manufacture its product candidates must be approved by the FDA pursuant to inspections that will be conducted after Eiger submits its marketing applications to the FDA. Eiger does not control the manufacturing process of, and is completely dependent on, its contract manufacturing partners for compliance with the regulatory requirements, known as cGMPs, for manufacture of Eiger’s product candidates. If Eiger’s contract manufacturers cannot successfully manufacture material that conforms to Eiger’s specifications and the strict regulatory requirements of the FDA or others, they will not be able to secure and/or maintain regulatory approval for their manufacturing facilities. In addition, Eiger has no control over the ability of its contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or a comparable foreign regulatory authority does not approve these facilities for the manufacture of its product candidates or if it withdraws any such approval in the future, Eiger may need to find alternative manufacturing facilities, which would significantly impact Eiger’s ability to develop, obtain regulatory approval for or market its product candidates, if approved.

Eiger does not yet have sufficient information to reliably estimate the cost of the commercial manufacturing of its product candidates, and the actual cost to manufacture its product candidates could materially and adversely affect the commercial viability of its product candidates. As a result, Eiger may never be able to develop a commercially viable product.

In addition, Eiger’s reliance on third-party manufacturers exposes Eiger to the following additional risks:

Each of these risks could delay Eiger’s clinical trials, the approval, if any of its product candidates by the FDA or the commercialization of its product candidates or result in higher costs or deprive Eiger of potential product revenue. In addition, Eiger relies on third parties to perform release testing on its product candidates prior to

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delivery to patients. If these tests are not appropriately conducted and test data are not reliable, patients could be put at risk of serious harm and could result in product liability suits.

The manufacture of medical products is complex and requires significant expertise and capital investment, including the development of advanced manufacturing techniques and process controls. Manufacturers of biologic products often encounter difficulties in production, particularly in scaling up and validating initial production and absence of contamination. These problems include difficulties with production costs and yields, quality control, including stability of the product, quality assurance testing, operator error, shortages of qualified personnel, as well as compliance with strictly enforced federal, state and foreign regulations. Furthermore, if contaminants are discovered in Eiger’s supply of its product candidates or in the manufacturing facilities, such manufacturing facilities may need to be closed for an extended period of time to investigate and remedy the contamination. Eiger cannot assure you that any stability or other issues relating to the manufacture of its product candidates will not occur in the future. Additionally, Eiger’s manufacturers may experience manufacturing difficulties due to resource constraints or as a result of labor disputes or unstable political environments. If Eiger’s manufacturers were to encounter any of these difficulties, or otherwise fail to comply with their contractual obligations, Eiger’s ability to provide its product candidates to patients in clinical trials would be jeopardized. Any delay or interruption in the supply of clinical trial supplies could delay the completion of clinical trials, increase the costs associated with maintaining clinical trial programs and, depending upon the period of delay, require Eiger to commence new clinical trials at additional expense or terminate clinical trials completely.

If the market opportunities for its product candidates are smaller than Eiger believes they are, Eiger may not meet its revenue expectations and, assuming approval of a product candidate, its business may suffer. Because the patient populations in the market for its product candidates may be small, Eiger must be able to successfully identify patients and acquire a significant market share to achieve profitability and growth.

Eiger focuses its research and product development on treatments for orphan diseases. Given the small number of patients who have the diseases that Eiger is targeting, its eligible patient population and pricing estimates may differ significantly from the actual market addressable by its product candidate. Its projections of both the number of people who have these diseases, as well as the subset of people with these diseases who have the potential to benefit from treatment with its product candidates, are based on its beliefs and estimates. These estimates have been derived from a variety of sources, including the scientific literature, patient foundations, or market research, and may prove to be incorrect. Further, new studies may change the estimated incidence or prevalence of these diseases. The number of patients may turn out to be lower than expected. For example, for lonafarnib, HDV is related to hepatitis B virus, and there is limited scientific literature in support of a causal link between these two viruses. Although Eiger believes that the data are supportive of the increased severity of hepatitis in the presence of hepatitis D with hepatitis B virus, there can be no assurance that its clinical trials will successfully address this recently observed condition. Likewise, the potentially addressable patient population for each of its product candidates may be limited or may not be amenable to treatment with its product candidates, and new patients may become increasingly difficult to identify or gain access to, which would adversely affect its results of operations and its business.

Eiger faces intense competition and rapid technological change and the possibility that Eiger’s competitors may develop therapies that are similar, more advanced, or more effective than Eiger’s, may adversely affect its financial condition and its ability to successfully commercialize its product candidates.

The biotechnology and pharmaceutical industries are intensely competitive and subject to rapid and significant technological change. Eiger is currently aware of various existing therapies that may compete with its product candidates. For example, Eiger has competitors both in the United States and internationally, including multinational pharmaceutical companies, specialty pharmaceutical companies and biotechnology companies. Some of the pharmaceutical and biotechnology companies Eiger expects to compete with include Gilead, Replicor, Novartis, Xoma and Arena as well as other smaller companies or biotechnology startups and large

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multinational pharmaceutical companies. Many of its competitors have substantially greater financial, technical, and other resources, such as larger research and development staff and experienced marketing and manufacturing organizations. Additional mergers and acquisitions in the biotechnology and pharmaceutical industries may result in even more resources being concentrated in Eiger’s competitors. As a result, these companies may obtain regulatory approval more rapidly than Eiger is able to and may be more effective in selling and marketing their products as well. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large, established companies. Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries. Eiger’s competitors may succeed in developing, acquiring, or licensing on an exclusive basis, products that are more effective or less costly than any product candidate that Eiger may develop, or achieve earlier patent protection, regulatory approval, product commercialization, and market penetration than Eiger does. Additionally, technologies developed by Eiger’s competitors may render its potential product candidates uneconomical or obsolete, and Eiger may not be successful in marketing its product candidates against competitors.

Eiger currently has limited marketing and sales experience. If Eiger is unable to establish sales and marketing capabilities or enter into agreements with third parties to market and sell its product candidates, Eiger may be unable to generate any revenue.

Although certain of its employees may have marketed, launched, and sold other pharmaceutical products in the past while employed at other companies, Eiger has no recent experience selling and marketing its product candidates and Eiger currently has no marketing or sales organization. To successfully commercialize any products that may result from its development programs, Eiger will need to invest in and develop these capabilities, either on its own or with others, which would be expensive, difficult and time consuming. Any failure or delay in the timely development of Eiger’s internal commercialization capabilities could adversely impact the potential for success of its products.

Further, given its lack of prior experience in marketing and selling biopharmaceutical products, Eiger may rely on future collaborators to commercialize its products. If collaborators do not commit sufficient resources to commercialize its future products and Eiger is unable to develop the necessary marketing and sales capabilities on its own, Eiger will be unable to generate sufficient product revenue to sustain or grow its business. Eiger may be competing with companies that currently have extensive and well-funded marketing and sales operations, in particular in the markets its product candidates are intended to address. Without appropriate capabilities, whether directly or through third party collaborators, Eiger may be unable to compete successfully against these more established companies.

The commercial success of any of Eiger’s current or future product candidate will depend upon the degree of market acceptance by physicians, patients, third-party payors, and others in the medical community.

Even with the approvals from the FDA and comparable foreign regulatory authorities, the commercial success of Eiger’s products will depend in part on the health care providers, patients, and third-party payors accepting its product candidates as medically useful, cost-effective, and safe. Any product that Eiger brings to the market may not gain market acceptance by physicians, patients, third-party payors and other health care providers. The degree of market acceptance of any of Eiger’s products will depend on a number of factors, including without limitation:

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Even if a product displays a favorable efficacy and safety profile upon approval, market acceptance of the product remains uncertain. Efforts to educate the medical community and third-party payors on the benefits of the products may require significant investment and resources and may never be successful. If its products fail to achieve an adequate level of acceptance by physicians, patients, third-party payors, and other health care providers, Eiger will not be able to generate sufficient revenue to become or remain profitable.

Failure to obtain or maintain adequate reimbursement or insurance coverage for new or current products could limit Eiger’s ability to market those products and decrease its ability to generate revenue.

The pricing, coverage, and reimbursement of Eiger’s products must be sufficient to support its commercial efforts and other development programs and the availability and adequacy of coverage and reimbursement by governmental and private payors are essential for most patients to be able to afford expensive treatments, particularly in orphan drug designated indications where the eligible patient population is small. Sales of Eiger’s product candidates will depend substantially, both domestically and abroad, on the extent to which the costs of its product candidates will be paid for or reimbursed by health maintenance, managed care, pharmacy benefit and similar healthcare management organizations, or government authorities, private health insurers, and other third-party payors. If coverage and reimbursement are not available, or are available only in limited amounts, Eiger may have to subsidize or provide products for free or Eiger may not be able to successfully commercialize its products.

In addition, there is significant uncertainty related to the insurance coverage and reimbursement for newly approved products. In the United States, the principal decisions about coverage and reimbursement for new drugs are typically made by the Centers for Medicare & Medicaid Services, or CMS, an agency within the U.S. Department of Health and Human Services, as CMS decides whether and to what extent a new drug will be covered and reimbursed under Medicare. Private payors tend to follow the coverage reimbursement policies established by CMS to a substantial degree. It is difficult to predict what CMS will decide with respect to reimbursement for products such as Eiger’s and what reimbursement codes its products may receive.

Outside the United States, international operations are generally subject to extensive governmental price controls and other price-restrictive regulations, and Eiger believes the increasing emphasis on cost-containment initiatives in Europe, Canada, and other countries has and will continue to put pressure on the pricing and usage of products. In many countries, the prices of products are subject to varying price control mechanisms as part of national health systems. Price controls or other changes in pricing regulation could restrict the amount that Eiger is able to charge for its products. Accordingly, in markets outside the United States, the potential revenue may be insufficient to generate commercially reasonable revenue and profits.

Moreover, increasing efforts by governmental and third-party payors in the United States and abroad to limit or reduce healthcare costs may result in restrictions on coverage and the level of reimbursement for new products and, as a result, they may not cover or provide adequate payment for its products. Eiger expects to experience pricing pressures in connection with products due to the increasing trend toward managed healthcare, including the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs has and is expected to continue to increase in the future. As a result, profitability of Eiger’s products may be more difficult to achieve even if they receive regulatory approval.

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Eiger intends to rely on a combination of exclusivity from orphan drug designation as well as patent rights for its product candidates and any future product candidates. If Eiger is unable to obtain or maintain exclusivity from the combination of these approaches, Eiger may not be able to compete effectively in its markets.

The Eiger business strategy is to focus on product candidates for which orphan drug designation may be obtained in the major markets of the world. In addition, Eiger relies or will upon a combination of patents, trade secret protection, and confidentiality agreements to protect the intellectual property related to its technologies and product candidates. For example, the portfolio of patents licensed from Merck expires before the anticipated launch date of the lonafarnib product candidate. Its success depends in large part on its and its licensors’ ability to obtain regulatory exclusivity and maintain patent and other intellectual property protection in the United States and in other countries with respect to its proprietary technology and products.

Under the Orphan Drug Act, the FDA may designate a product as an orphan drug if it is intended to treat a rare disease or condition, defined as a patient population of fewer than 200,000 in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States. In the European Union, the EMA’s Committee for Orphan Medicinal Products, or COMP, grants orphan drug designation to promote the development of products that are intended for the diagnosis, prevention, or treatment of a life-threatening or chronically debilitating condition affecting not more than five in 10,000 persons in the European Union. Additionally, designation is granted for products intended for the diagnosis, prevention, or treatment of a life-threatening, seriously debilitating or serious and chronic condition when, without incentives, it is unlikely that sales of the drug in the European Union would be sufficient to justify the necessary investment in developing the drug or biological product or where there is no satisfactory method of diagnosis, prevention, or treatment, or, if such a method exists, the medicine must be of significant benefit to those affected by the condition.

In the United States, orphan drug designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages, and user-fee waivers. In addition, if a product receives the first FDA approval for the indication for which it has orphan drug designation, the product is entitled to orphan drug exclusivity, which means the FDA may not approve any other application to market the same drug for the same indication for a period of seven years, except in limited circumstances, such as a showing of clinical superiority over the product with orphan exclusivity or where the manufacturer is unable to assure sufficient product quantity. In the European Union, orphan drug designation entitles a party to financial incentives such as reduction of fees or fee waivers and ten years of market exclusivity following drug or biological product approval. This period may be reduced to six years if the orphan drug designation criteria are no longer met, including where it is shown that the product is sufficiently profitable not to justify maintenance of market exclusivity.

Because the extent and scope of patent protection for its products may in some cases be limited, orphan drug designation is especially important for Eiger’s products for which orphan drug designation may be available. For eligible drugs, Eiger plans to rely on the exclusivity period under the Orphan Drug Act to maintain a competitive position. If Eiger does not obtain orphan drug exclusivity for its drug products and biologic products that do not have broad patent protection, its competitors may then sell the same drug to treat the same condition sooner than if Eiger had obtained orphan drug exclusivity and its revenue will be reduced.

Even though Eiger has orphan drug designation for lonafarnib in the United States and Europe, Eiger may not be the first to obtain marketing approval for any particular orphan indication due to the uncertainties associated with developing pharmaceutical products. Further, even if Eiger obtains orphan drug exclusivity for a product, that exclusivity may not effectively protect the product from competition because different drugs with different active moieties can be approved for the same condition. Even after an orphan drug is approved, the FDA or EMA can subsequently approve the same drug with the same active moiety for the same condition if the FDA or EMA concludes that the later drug is safer, more effective, or makes a major contribution to patient care. Orphan drug designation neither shortens the development time or regulatory review time of a product candidate nor gives the product candidate any advantage in the regulatory review or approval process.

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Eiger has sought to protect its proprietary position by filing patent applications in the United States and abroad related to its product candidates that are important to its business. This process is expensive and time consuming, and Eiger may not be able to file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner. It is also possible that Eiger will fail to identify patentable aspects of its research and development output before it is too late to obtain patent protection.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain and involves complex legal and factual questions for which legal principles remain unsolved. The patent applications that Eiger owns or in-licenses may fail to result in issued patents with claims that cover its product candidates in the United States or in other foreign countries. There is no assurance that all potentially relevant prior art relating to its patents and patent applications has been found, which can invalidate a patent or prevent a patent from issuing from a pending patent application. Even if patents do successfully issue, and even if such patents cover Eiger’s product candidates, third parties may challenge their validity, enforceability, or scope, which may result in such patents being narrowed, found unenforceable or invalidated. Furthermore, even if they are unchallenged, Eiger’s patents and patent applications may not adequately protect its intellectual property, provide exclusivity for its product candidates, or prevent others from designing around the Eiger claims. Any of these outcomes could impair Eiger’s ability to prevent competition from third parties, which may have an adverse impact on its business.

Eiger, independently or together with its licensors, has filed several patent applications covering various aspects of its product candidates. Eiger cannot offer any assurances about which, if any, patents will issue, the breadth of any such patent or whether any issued patents will be found invalid and unenforceable or will be threatened by third parties. Any successful opposition to these patents or any other patents owned by or licensed to Eiger after patent issuance could deprive Eiger of rights necessary for the successful commercialization of any product candidates that Eiger may develop. Further, if Eiger encounters delays in regulatory approvals, the period of time during which Eiger could market a product candidate under patent protection could be reduced.

Although Eiger has licensed a number of patents covering methods of use and certain compositions of matter, Eiger does not have complete patent protection for its product candidates. For example, the patent coverage for lonafarnib expires before the anticipated launch date. Likewise, most of the patents covering products that Eiger has licensed in from Stanford University have limited protection outside of the United States. Therefore, a competitor could develop the same or similar product that may compete with its product candidate.

Certain of Eiger’s product licenses are limited to specified indications or therapeutic areas which may result in the same compound being developed and commercialized by a third party whom Eiger has no control over or rights against. This may result in safety data, pricing or off label uses from that third party’s product that may negatively affect the development and commercialization of its product candidates. For example, Kura has an exclusive license to tipifarnib for use in cancer indications while Eiger has a license for anti-viral indications. As a result of Kura’s right to use the same compound in a different indication, it is possible that development and sales may impact the Eiger product development and commercialization efforts. If Eiger cannot obtain and maintain effective protection of exclusivity from its regulatory efforts and intellectual property rights, including patent protection, for its product candidates, Eiger may not be able to compete effectively and its business and results of operations would be harmed.

Eiger may not have sufficient patent term protections for its products to effectively protect its business.

Patents have a limited term. In the United States, the statutory expiration of a patent is generally 20 years after it is filed. Although various extensions may be available, the life of a patent, and the protection it affords, is limited. Even if patents covering its product candidates are obtained, once the patent life has expired for a product, Eiger may be open to competition from generic medications. In addition, upon issuance in the United States any patent term can be adjusted based on certain delays caused by the applicant(s) or the United States

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Patent and Trademark Office, or USPTO. For example, a patent term can be reduced based on certain delays caused by the patent applicant during patent prosecution.

Patent term extensions under the Hatch-Waxman Act in the United States and under supplementary protection certificates in Europe may be available to extend the patent or data exclusivity terms of products. With respect to ubenimex, lonafarnib and exendin (9-39), a substantial portion of the potential commercial opportunity will likely rely on patent term extensions, and Eiger cannot provide any assurances that any such patent term extensions will be obtained and, if so, for how long. As a result, Eiger may not be able to maintain exclusivity for its products for an extended period after regulatory approval, which would negatively impact its business and results of operations. If Eiger does not have sufficient patent terms or regulatory exclusivity to protect its products, its business and results of operations will be adversely affected.

Patent laws and rule changes could increase the uncertainties and costs surrounding the prosecution of Eiger’s patent applications and the enforcement or defense of its issued patents.

Changes in either the patent laws or interpretation of the patent laws in the United States and other countries may diminish the value of its patents or narrow the scope of Eiger’s patent protection. The laws of foreign countries may not protect its rights to the same extent as the laws of the United States. Publications of discoveries in the scientific literature often lag behind the actual discoveries, and patent applications in the United States and other jurisdictions are typically not published until 18 months after filing, or in some cases not at all. Eiger therefore cannot be certain that it or its licensors were the first to make the invention claimed in its owned and licensed patents or pending applications, or that Eiger or its licensor were the first to file for patent protection of such inventions. Assuming the other requirements for patentability are met, in the United States prior to March 15, 2013, the first to make the claimed invention is entitled to the patent, while outside the United States, the first to file a patent application is entitled to the patent. After March 15, 2013, under the Leahy-Smith America Invents Act, or the Leahy-Smith Act, enacted on September 16, 2011, the United States has moved to a first to file system. The Leahy-Smith Act also includes a number of significant changes that affect the way patent applications will be prosecuted and may also affect patent litigation. The effects of these changes are currently unclear as the USPTO must still implement various regulations, the courts have yet to address any of these provisions and the applicability of the act and new regulations on specific patents discussed herein have not been determined and would need to be reviewed. In general, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of Eiger’s patent applications and the enforcement or defense of Eiger’s issued patents, all of which could have a material adverse effect on Eiger’s business and financial condition.

If Eiger is unable to maintain effective proprietary rights for its product candidates or any future product candidates, Eiger may not be able to compete effectively in its markets.

In addition to the protection afforded by patents, Eiger relies on trade secret protection and confidentiality agreements to protect proprietary know-how that is not patentable or that Eiger elects not to patent, processes for which patents are difficult to enforce and any other elements of its product candidate discovery and development processes that involve proprietary know-how, information or technology that is not covered by patents. However, trade secrets can be difficult to protect. Eiger seeks to protect its proprietary technology and processes, in part, by entering into confidentiality agreements with its employees, consultants, scientific advisors, and contractors. Eiger also seeks to preserve the integrity and confidentiality of its data and trade secrets by maintaining physical security of its premises and physical and electronic security of its information technology systems. While Eiger has confidence in these individuals, organizations and systems, agreements or security measures may be breached, and Eiger may not have adequate remedies for any breach. In addition, its trade secrets may otherwise become known or be independently discovered by competitors.

Although Eiger expects all of its employees and consultants to assign their inventions to Eiger, and all of its employees, consultants, advisors, and any third parties who have access to its proprietary know-how,

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information, or technology to enter into confidentiality agreements, Eiger cannot provide any assurances that all such agreements have been duly executed or that its trade secrets and other confidential proprietary information will not be disclosed or that competitors will not otherwise gain access to its trade secrets or independently develop substantially equivalent information and techniques. Misappropriation or unauthorized disclosure of Eiger’s trade secrets could impair its competitive position and may have a material adverse effect on its business. Additionally, if the steps taken to maintain its trade secrets are deemed inadequate, Eiger may have insufficient recourse against third parties for misappropriating the trade secret.

Third-party claims of intellectual property infringement may prevent or delay Eiger’s development and commercialization efforts.

Eiger’s commercial success depends in part on its avoiding infringement of the patents and proprietary rights of third parties. There have been many lawsuits and other proceedings involving patent and other intellectual property rights in the biotechnology and pharmaceutical industries, including patent infringement lawsuits, interferences, oppositions, and reexamination proceedings before the USPTO and corresponding foreign patent offices. Numerous U.S. and foreign issued patents and pending patent applications, which are owned by third parties, exist in the fields in which Eiger is developing product candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that its product candidates may be subject to claims of infringement of the patent rights of third parties.

Third parties may assert that Eiger is employing their proprietary technology without authorization. There may be third-party patents or patent applications with claims to materials, formulations, methods of manufacture, or methods for treatment related to the use or manufacture of its product candidates. Eiger has conducted freedom to operate analyses with respect to only certain of its product candidates, and therefore Eiger does not know whether there are any third-party patents that would impair its ability to commercialize these product candidates. Eiger also cannot guarantee that any of its analyses are complete and thorough, nor can Eiger be sure that Eiger has identified each and every patent and pending application in the United States and abroad that is relevant or necessary to the commercialization of its product candidates. Because patent applications can take many years to issue, there may be currently pending patent applications that may later result in issued patents that its product candidates may infringe.

In addition, third parties may obtain patents in the future and claim that use of its technologies infringes upon these patents. If any third-party patents were held by a court of competent jurisdiction to cover aspects of its formulations, the manufacturing process of any of its product candidates, methods of use, any molecules formed during the manufacturing process or any final product itself, the holders of any such patents may be able to block its ability to commercialize such product candidate unless Eiger obtained a license under the applicable patents, or until such patents expire or are finally determined to be invalid or unenforceable. Such a license may not be available on commercially reasonable terms, or at all.

Parties making claims against Eiger may obtain injunctive or other equitable relief, which could effectively block its ability to further develop and commercialize one or more of its product candidates. Defense of these claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of employee resources from its business. In the event of a successful claim of infringement against Eiger, Eiger may have to pay substantial damages, including treble damages and attorneys’ fees for willful infringement, pay royalties, redesign its infringing products or obtain one or more licenses from third parties, which may be impossible or require substantial time and monetary expenditure.

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Eiger may not be successful in meeting its diligence obligations under its existing license agreements necessary to maintain its product candidate licenses in effect. In addition, if required in order to commercialize its product candidates, Eiger may be unsuccessful in obtaining or maintaining necessary rights to its product candidates through acquisitions and in-licenses.

Eiger currently has rights to the intellectual property, through licenses from third parties and under patents that Eiger does not own, to develop and commercialize its product candidates. Because its programs may require the use of proprietary rights held by third parties, the growth of its business will likely depend in part on its ability to maintain in effect these proprietary rights. For example, Eiger has certain specified diligence obligations under its Stanford University license agreements for its ubenimex and lonafarnib product candidates. Eiger may not be able to achieve the required diligence milestones in a timely manner, which may result in a right of termination by Stanford University, and Eiger may be unable to successfully negotiate an extension or waiver of those termination rights. Any termination of license agreements with third parties with respect to its product candidates would be expected to negatively impact its business prospects.

Eiger may be unable to acquire or in-license any compositions, methods of use, processes, or other third-party intellectual property rights from third parties that Eiger identifies as necessary for its product candidates. The licensing and acquisition of third-party intellectual property rights is a competitive area, and a number of more established companies are also pursuing strategies to license or acquire third-party intellectual property rights that Eiger may consider attractive. These established companies may have a competitive advantage over Eiger due to their size, cash resources, and greater clinical development and commercialization capabilities. In addition, companies that perceive Eiger to be a competitor may be unwilling to assign or license rights to Eiger. Even if Eiger is able to license or acquire third-party intellectual property rights that are necessary for its product candidates, there can be no assurance that they will be available on favorable terms.

Eiger collaborates with U.S. and foreign academic institutions to identify product candidates, accelerate its research and conduct development. Typically, these institutions have provided Eiger with an option to negotiate an exclusive license to any of the institution’s rights in the patents or other intellectual property resulting from the collaboration. Regardless of such option, Eiger may be unable to negotiate a license within the specified timeframe or under terms that are acceptable to Eiger. If Eiger is unable to do so, the institution may offer the intellectual property rights to other parties, potentially blocking its ability to pursue a program of interest to Eiger.

If Eiger is unable to successfully obtain and maintain rights to required third-party intellectual property, Eiger may have to abandon development of that product candidate or pay additional amounts to the third party, and its business and financial condition could suffer.

Eiger’s product candidates may be subject to generic competition.

Under the Hatch-Waxman Act, a pharmaceutical manufacturer may file an abbreviated new drug application, or ANDA, seeking approval of a generic copy of an approved innovator product. Under the Hatch-Waxman Act, a manufacturer may also submit an NDA under section 505(b)(2) that references the FDA’s finding of safety and effectiveness of a previously approved drug. A 505(b)(2) NDA product may be for a new or improved version of the original innovator product. Innovative small molecule drugs may be eligible for certain periods of regulatory exclusivity (e.g., five years for new chemical entities, three years for changes to an approved drug requiring a new clinical study, seven years for orphan drugs), which preclude FDA approval (or in some circumstances, FDA filing and review of) an ANDA or 505(b)(2) NDA relying on the FDA’s finding of safety and effectiveness for the innovative drug. In addition to the benefits of regulatory exclusivity, an innovator NDA holder may have patents claiming the active ingredient, product formulation or an approved use of the drug, which would be listed with the product in the FDA publication, “Approved Drug Products with Therapeutic Equivalence Evaluations,” known as the “Orange Book.” If there are patents listed in the Orange Book, a generic applicant that seeks to market its product before expiration of the patents must include in the ANDA or 505(b)(2) what is known as a

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“Paragraph IV certification,” challenging the validity or enforceability of, or claiming non-infringement of, the listed patent or patents. Notice of the certification must be given to the innovator, too, and if within 45 days of receiving notice the innovator sues to protect its patents, approval of the ANDA is stayed for 30 months, or as lengthened or shortened by the court.

If there are patents listed for its product candidates in the Orange Book, ANDAs and 505(b)(2) NDAs with respect to those product candidates would be required to include a certification as to each listed patent indicating whether the ANDA applicant does or does not intend to challenge the patent. Eiger cannot predict whether any patents issuing from its pending patent applications will be eligible for listing in the Orange Book, how any generic competitor would address such patents, whether Eiger would sue on any such patents, or the outcome of any such suit.

Eiger may not be successful in securing or maintaining proprietary patent protection for products and technologies Eiger develops or licenses. Moreover, if any patents that are granted and listed in the Orange Book are successfully challenged by way of a Paragraph IV certification and subsequent litigation, the affected product could more immediately face generic competition and its sales would likely decline materially. Should sales decline, Eiger may have to write off a portion or all of the intangible assets associated with the affected product and its results of operations and cash flows could be materially and adversely affected.

The patent protection and patent prosecution for some of Eiger’s product candidates is dependent on third parties.

While Eiger normally seeks and gains the right to fully prosecute the patents relating to its product candidates, there may be times when patents relating to its product candidates are controlled by its licensors. This is the case with its agreements with Stanford University and Nippon Kayaku, each of whom is primarily responsible for the prosecution of patents and patent applications licensed to Eiger under the applicable collaboration agreements. If they or any of its future licensors fail to appropriately and broadly prosecute and maintain patent protection for patents covering any of its product candidates, its ability to develop and commercialize those product candidates may be adversely affected and Eiger may not be able to prevent competitors from making, using, importing, and selling competing products. In addition, even where Eiger now has the right to control patent prosecution of patents and patent applications Eiger has licensed from third parties, Eiger may still be adversely affected or prejudiced by actions or inactions of its licensors in effect from actions prior to Eiger assuming control over patent prosecution.

If Eiger fails to comply with obligations in the agreements under which Eiger licenses intellectual property and other rights from third parties or otherwise experience disruptions to its business relationships with its licensors, Eiger could lose license rights that are important to its business.

Eiger is a party to a number of intellectual property license and supply agreements that are important to its business and expects to enter into additional license agreements in the future. Eiger’s existing agreements impose, and Eiger expects that future license agreements will impose, various diligence, milestone payment, royalty, purchasing, and other obligations on it. If Eiger fails to comply with its obligations under these agreements, or Eiger is subject to a bankruptcy, its agreements may be subject to termination by the licensor, in which event Eiger would not be able to develop, manufacture, or market products covered by the license or subject to supply commitments.

Although Eiger is not currently involved in any litigation, Eiger may be involved in lawsuits to protect or enforce its patents or the patents of its licensors, which could be expensive, time consuming, and unsuccessful.

Competitors may infringe Eiger’s patents or the patents of its licensors. Although Eiger is not currently involved in any litigation, if Eiger or one of its licensing partners were to initiate legal proceedings against a third party to enforce a patent covering one of its product candidates, the defendant could counterclaim that the patent covering

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its product candidate is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, or non-enablement. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant information from the USPTO, or made a misleading statement, during prosecution. The outcome following legal assertions of invalidity and unenforceability is unpredictable.

Interference proceedings provoked by third parties or brought by Eiger or declared by the USPTO may be necessary to determine the priority of inventions with respect to Eiger’s patents or patent applications or those of its licensors. An unfavorable outcome could require Eiger to cease using the related technology or to attempt to license rights to it from the prevailing party. Eiger’s business could be harmed if the prevailing party does not offer Eiger a license on commercially reasonable terms. Its defense of litigation or interference proceedings may fail and, even if successful, may result in substantial costs and distract its management and other employees. In addition, the uncertainties associated with litigation could have a material adverse effect on its ability to raise the funds necessary to continue its clinical trials, continue its research programs, license necessary technology from third parties, or enter into development partnerships that would help Eiger bring its product candidates to market.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of Eiger confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions, or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of its common stock.

Eiger may be subject to claims that its employees, consultants, or independent contractors have wrongfully used or disclosed confidential information of third parties or that its employees have wrongfully used or disclosed alleged trade secrets of their former employers.

Eiger employs individuals who were previously employed at universities or other biotechnology or pharmaceutical companies, including its competitors or potential competitors. Although Eiger has written agreements and make every effort to ensure that its employees, consultants, and independent contractors do not use the proprietary information or intellectual property rights of others in their work for Eiger, and Eiger is not currently subject to any claims that its employees, consultants, or independent contractors have wrongfully used or disclosed confidential information of third parties, Eiger may in the future be subject to such claims. Litigation may be necessary to defend against these claims. If Eiger fails in defending any such claims, in addition to paying monetary damages, Eiger may lose valuable intellectual property rights or personnel, which could adversely impact its business. Even if Eiger is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Eiger may not be able to protect its intellectual property rights throughout the world.

Filing, prosecuting, and defending patents on product candidates in all countries throughout the world would be prohibitively expensive, and its intellectual property rights in some countries outside the United States can be less extensive than those in the United States. In addition, the laws of some foreign countries do not protect intellectual property rights to the same extent as federal and state laws in the United States. Competitors may use Eiger’s technologies in jurisdictions where Eiger has not obtained patent protection to develop its own products and may also export infringing products to territories where Eiger has patent protection, but enforcement is not as strong as that in the United States. These products may compete with its products and its patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents, trade secrets, and other intellectual property protection, particularly those

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relating to biotechnology products, which could make it difficult for Eiger to stop the infringement of its patents or marketing of competing products in violation of its proprietary rights generally. Proceedings to enforce Eiger’s patent rights in foreign jurisdictions, whether or not successful, could result in substantial costs and divert Eiger’s efforts and attention from other aspects of its business, could put Eiger’s patents at risk of being invalidated or interpreted narrowly and its patent applications at risk of not issuing and could provoke third parties to assert claims against Eiger. Eiger may not prevail in any lawsuits that Eiger initiates and the damages or other remedies awarded, if any, may not be commercially meaningful. Accordingly, its efforts to enforce its intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that Eiger develops or licenses.

Risks Related to Eiger’s Business Operations

Eiger has identified a material weakness in its internal control over financial reporting and may identify additional material weaknesses in the future or otherwise fail to maintain an effective system of internal control, which may result in material misstatements of Eiger’s financial statements or cause Eiger to fail to meet its periodic reporting obligations.

Prior to the merger, Eiger was a private company and had limited accounting and financial reporting personnel and other resources with which to address its internal controls and procedures. In connection with the audit of Eiger’s consolidated financial statements for the years ended December 31, 2014 and 2013, Eiger and its independent auditors identified a material weakness in Eiger’s internal control over financial reporting. A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of the subject company’s annual or interim financial statements will not be prevented or detected on a timely basis. Eiger’s lack of sufficient accounting personnel has resulted in the identification of a material weakness in Eiger’s internal control over financial reporting. Specifically, the material weakness that was identified related to a lack of sufficient accounting resources and personnel that has limited Eiger’s ability to adequately segregate duties, establish defined accounting policies and procedures and perform timely reviews of account reconciliations.

To address this material weakness, Eiger plans to hire additional accounting personnel, establish and document accounting policies and procedures, and implement management review controls. While Eiger intends to implement a plan to remediate this material weakness, Eiger cannot predict the success of such plan or the outcome of Eiger’s assessment of these plans at this time. Eiger can give no assurance that this implementation will remediate this deficiency in internal control or that additional material weaknesses or significant deficiencies in Eiger’s internal control over financial reporting will not be identified in the future. Eiger’s failure to implement and maintain effective internal control over financial reporting could result in errors in Eiger’s financial statements that could result in a restatement of Eiger’s financial statements or cause Eiger to fail to meet its reporting obligations.

Eiger’s future success depends in part on its ability to retain its President and Chief Executive Officer and to attract, retain, and motivate other qualified personnel.

Eiger is highly dependent on David Cory, its President and Chief Executive Officer, the loss of whose services may adversely impact the achievement of its objectives. Mr. Cory could leave Eiger’s employment at any time, as he is an “at will” employee. Recruiting and retaining other qualified employees, consultants, and advisors for Eiger’s business, including scientific and technical personnel, will also be critical to Eiger success. There is currently a shortage of highly qualified personnel in Eiger’s industry, which is likely to continue. As a result, competition for personnel is intense and the turnover rate can be high. Eiger may not be able to attract and retain personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for individuals with similar skill sets. In addition, failure to succeed in development and commercialization of Eiger’s product candidates may make it more challenging to recruit and retain qualified personnel. The inability to recruit and retain qualified personnel, or the loss of the services of Mr. Cory may

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impede the progress of Eiger’s research, development, and commercialization objectives and would negatively impact Eiger’s ability to succeed in its in-licensing strategy.

Eiger will need to expand its organization and Eiger may experience difficulties in managing this growth, which could disrupt its operations.

As of September 30, 2015, Eiger had seven full-time employees. As Eiger’s development and commercialization plans and strategies develop, Eiger expects to need additional managerial, operational, sales, marketing, financial, legal, and other resources. Its management may need to divert a disproportionate amount of its attention away from its day-to-day activities and devote a substantial amount of time to managing these growth activities. Eiger may not be able to effectively manage the expansion of its operations, which may result in weaknesses in its infrastructure, operational mistakes, loss of business opportunities, loss of employees, and reduced productivity among remaining employees. Eiger’s expected growth could require significant capital expenditures and may divert financial resources from other projects, such as the development of additional product candidates. If its management is unable to effectively manage its growth, its expenses may increase more than expected, its ability to generate and/or grow revenue could be reduced and Eiger may not be able to implement its business strategy. Eiger’s future financial performance and its ability to commercialize product candidates and compete effectively will depend, in part, on its ability to effectively manage any future growth.

Failure in Eiger’s information technology and storage systems could significantly disrupt the operation of Eiger’s business.

Eiger’s ability to execute its business plan and maintain operations depends on the continued and uninterrupted performance of its information technology, or IT, systems. IT systems are vulnerable to risks and damages from a variety of sources, including telecommunications or network failures, malicious human acts and natural disasters. Moreover, despite network security and back-up measures, some of Eiger’s and its vendors’ servers are potentially vulnerable to physical or electronic break-ins, computer viruses and similar disruptive problems. Despite precautionary measures to prevent unanticipated problems that could affect its IT systems, sustained or repeated system failures that interrupt its ability to generate and maintain data could adversely affect its ability to operate its business.

Eiger may not be successful in any efforts to identify, license, discover, develop, or commercialize additional product candidates.

Although a substantial amount of Eiger’s effort will focus on the continued clinical testing, potential approval, and commercialization of its existing product candidates, the success of Eiger’s business is also expected to depend in part upon its ability to identify, license, discover, develop, or commercialize additional product candidates. Research programs to identify new product candidates require substantial technical, financial, and human resources. Eiger may focus its efforts and resources on potential programs or product candidates that ultimately prove to be unsuccessful. Eiger’s research programs or licensing efforts may fail to yield additional product candidates for clinical development and commercialization for a number of reasons, including but not limited to the following:

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If any of these events occur, Eiger may be forced to abandon its development efforts for a program or programs, or Eiger may not be able to identify, license, discover, develop, or commercialize additional product candidates, which would have a material adverse effect on its business and could potentially cause Eiger to cease operations.

Healthcare legislative reform measures may have a material adverse effect on Eiger’s business and results of operations.

In the United States, there have been and continue to be a number of legislative initiatives to contain healthcare costs. For example, in March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or the Health Care Reform Law, was passed, which substantially changes the way health care is financed by both governmental and private insurers, and significantly impacts the U.S. pharmaceutical industry. The Health Care Reform Law, among other things, addresses a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted, or injected, increases the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extends the rebate program to individuals enrolled in Medicaid managed care organizations, establishes annual fees and taxes on manufacturers of certain branded prescription drugs, and promotes a new Medicare Part D coverage gap discount program.

In addition, other legislative changes have been proposed and adopted in the United States since the Health Care Reform Law was enacted and Eiger expects that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand or lower pricing for its product candidates, or additional pricing pressures.

Eiger may be subject, directly or indirectly, to federal and state healthcare fraud and abuse laws, false claims laws, and health information privacy and security laws. If Eiger is unable to comply, or has not fully complied, with such laws, it could face substantial penalties.

If Eiger obtains FDA approval for any of its product candidates and begins commercializing those products in the United States, its operations may be subject to various federal and state fraud and abuse laws, including, without limitation, the federal Anti-Kickback Statute, the federal False Claims Act, and physician sunshine laws and regulations. These laws may impact, among other things, its proposed sales, marketing, and education programs. In addition, Eiger may be subject to patient privacy regulation by both the federal government and the states in which Eiger conduct its business. The laws that may affect its ability to operate include:

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Because of the breadth of these laws and the narrowness of the statutory exceptions and safe harbors available, it is possible that some of Eiger’s business activities could be subject to challenge under one or more of such laws. In addition, recent health care reform legislation has strengthened these laws. For example, the Health Care Reform Law, among other things, amends the intent requirement of the federal anti-kickback and criminal healthcare fraud statutes. A person or entity no longer needs to have actual knowledge of this statute or specific intent to violate it. Moreover, the Health Care Reform Law provides that the government may assert that a claim including items or services resulting from a violation of the federal anti-kickback statute constitutes a false or fraudulent claim for purposes of the False Claims Act.

If Eiger’s operations are found to be in violation of any of the laws described above or any other governmental regulations that apply to Eiger, Eiger may be subject to penalties, including civil and criminal penalties, damages, fines, exclusion from participation in government health care programs, such as Medicare and Medicaid, imprisonment, and the curtailment or restructuring of its operations, any of which could adversely affect its ability to operate Eiger’s business and its results of operations.

If Eiger fails to comply with environmental, health and safety laws and regulations, Eiger could become subject to fines or penalties or incur costs that could have a material adverse effect on the success of its business.

Eiger’s research and development activities and its third-party manufacturers’ and suppliers’ activities involve the controlled storage, use, and disposal of hazardous materials, including the components of its product candidates and other hazardous compounds. Eiger and its manufacturers and suppliers are subject to laws and regulations governing the use, manufacture, storage, handling, and disposal of these hazardous materials. In some cases, these hazardous materials and various wastes resulting from their use are stored at Eiger’s and its manufacturers’ facilities pending their use and disposal. Eiger cannot eliminate the risk of contamination, which could cause an interruption of its commercialization efforts, research and development efforts and business operations, environmental damage resulting in costly clean-up and liabilities under applicable laws and

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regulations governing the use, storage, handling, and disposal of these materials and specified waste products. Although Eiger believes that the safety procedures utilized by it and its third-party manufacturers for handling and disposing of these materials generally comply with the standards prescribed by these laws and regulations, Eiger cannot guarantee that this is the case or eliminate the risk of accidental contamination or injury from these materials. In such an event, Eiger may be held liable for any resulting damages and such liability could exceed its resources and state or federal or other applicable authorities may curtail Eiger’s use of certain materials and/or interrupt its business operations. Furthermore, environmental laws and regulations are complex, change frequently, and have tended to become more stringent. Eiger cannot predict the impact of such changes and cannot be certain of its future compliance. Eiger does not currently carry biological or hazardous waste insurance coverage.

Eiger or the third parties upon whom it depends may be adversely affected by earthquakes or other natural disasters and its business continuity and disaster recovery plans may not adequately protect Eiger from a serious disaster.

Its corporate headquarters are located in the San Francisco Bay Area which has in the past experienced severe earthquakes and other natural disasters. Eiger does not carry earthquake insurance. Earthquakes or other natural disasters could severely disrupt its operations or those of its collaborators, and have a material adverse effect on its business, results of operations, financial condition, and prospects. If a natural disaster, terrorist attack, power outage, or other event occurred that prevented Eiger from using or damaged critical elements of its business and operations (such as the manufacturing facilities of its third-party contract manufacturers) its business may be disrupted for a substantial period of time. Eiger has limited or no disaster recovery and business continuity plans in place currently and its business would be impaired in the event of a serious disaster or similar event. Eiger may incur substantial expenses to develop and implement any disaster recovery and business continuity plans, which could have a material adverse effect on its business.

Eiger’s principal stockholders own a significant percentage of its stock and will be able to exert significant control over matters subject to stockholder approval.

Eiger’s principal stockholders and their affiliates currently beneficially own in excess of 70% of Eiger’s outstanding voting stock. Therefore, these stockholders have the ability and may continue to have the ability to influence Eiger through this ownership position. These stockholders may be able to determine some or all matters requiring stockholder approval. For example, these stockholders, acting together, may be able to control elections of directors, amendments of organizational documents, or approval of any merger, sale of assets, or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for Eiger’s common stock that you may believe are in your best interest as one of Eiger’s stockholders.

Risks Related to the Combined Organization

In determining whether you should approve the merger, the issuance of shares of Celladon common stock and other matters related to the merger, as the case may be, you should carefully read the following risk factors in addition to the risks described above.

Celladon’s stock price is expected to be volatile, and the market price of its common stock may drop following the merger.

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

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

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

The combined organization will incur costs and demands upon management as a result of complying with the laws and regulations affecting public companies.

The combined organization will incur significant legal, accounting and other expenses that Eiger did not incur as a private company, including costs associated with public company reporting requirements. The combined organization will also incur costs associated with corporate governance requirements, including requirements under the Sarbanes-Oxley Act, as well as new rules implemented by the SEC and The NASDAQ Stock Market LLC. These rules and regulations are expected to increase the combined organization’s legal and financial compliance costs and to make some activities more time-consuming and costly. For example, the combined organization’s management team will consist of certain executive officers of Eiger prior to the merger, some of whom have not previously managed and operated a public company. These executive officers and other personnel will need to devote substantial time to gaining expertise regarding operations as a public company and compliance with applicable laws and regulations. These rules and regulations may also make it difficult and expensive for the combined organization to obtain directors’ and officers’ liability insurance. As a result, it may be more difficult for the combined organization to attract and retain qualified individuals to serve on the combined organization’s board of directors or as executive officers of the combined organization, which may adversely affect investor confidence in the combined organization and could cause the combined organization’s business or stock price to suffer.

Anti-takeover provisions in the combined organization’s charter documents and under Delaware law could make an acquisition of the combined organization more difficult and may prevent attempts by the combined organization stockholders to replace or remove the combined organization management.

Provisions in the combined organization’s certificate of incorporation and bylaws may delay or prevent an acquisition or a change in management. These provisions include a classified board of directors, a prohibition on actions by written consent of the combined organization’s stockholders and the ability of the board of directors to issue preferred stock without stockholder approval. In addition, because the combined organization will be incorporated in Delaware, it is governed by the provisions of Section 203 of the DGCL, which prohibits stockholders owning in excess of 15% of the outstanding combined organization voting stock from merging or combining with the combined organization. Although Celladon and Eiger believe these provisions collectively will provide for an opportunity to receive higher bids by requiring potential acquirors to negotiate with the combined organization’s board of directors, they would apply even if the offer may be considered beneficial by some stockholders. In addition, these provisions may frustrate or prevent any attempts by the combined organization’s stockholders to replace or remove then current management by making it more difficult for stockholders to replace members of the board of directors, which is responsible for appointing the members of management.

Celladon and Eiger do not anticipate that the combined organization will pay any cash dividends in the foreseeable future.

The current expectation is that the combined organization will retain its future earnings to fund the development and growth of the combined organization’s business. As a result, capital appreciation, if any, of the common stock of the combined organization will be your sole source of gain, if any, for the foreseeable future.

Future sales of shares by existing stockholders could cause the combined organization’s stock price to decline.

If existing stockholders of Celladon and Eiger sell, or indicate an intention to sell, substantial amounts of the combined organization’s common stock in the public market after legal restrictions on resale discussed in this

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proxy statement/prospectus/information statement lapse, the trading price of the common stock of the combined organization could decline. Based on shares outstanding as of November 30, 2015 and shares expected to be issued upon completion of the merger, the combined organization is expected to have outstanding a total of approximately 7.0 million shares of common stock (after giving effect to the proposed 1-for-15 reverse stock split) immediately following the completion of the merger. Approximately 2.9 million of such shares of common stock will be freely tradable, without restriction, in the public market. Approximately 4.0 million of such shares will be held by directors, executive officers of the combined organization and other affiliates and will be subject to volume limitations under Rule 144 under the Securities Act and various vesting agreements. In addition, approximately 25,100 shares of common stock that are subject to outstanding options of Eiger as of November 30, 2015 (after giving effect to the proposed 1-for-15 reverse stock split) will become eligible for sale in the public market to the extent permitted by the provisions of various vesting agreements and Rules 144 and 701 under the Securities Act. If these additional shares are sold, or if it is perceived that they will be sold, in the public market, the trading price of the combined organization common stock could decline.

If the ownership of the combined organization common stock is highly concentrated, it may prevent you and other stockholders from influencing significant corporate decisions and may result in conflicts of interest that could cause the combined organization stock price to decline.

Executive officers and directors of the combined organization and their affiliates are expected to beneficially own or control approximately 49.3% of the outstanding shares of the combined organization common stock following the completion of the merger. Accordingly, these executive officers, directors and their affiliates, acting as a group, will have substantial influence over the outcome of corporate actions requiring stockholder approval, including the election of directors, any merger, consolidation or sale of all or substantially all of the combined organization assets or any other significant corporate transactions. These stockholders may also delay or prevent a change of control of the combined organization, even if such a change of control would benefit the other stockholders of the combined organization. The significant concentration of stock ownership may adversely affect the trading price of the combined organization’s common stock due to investors’ perception that conflicts of interest may exist or arise.

Because the merger will result in an ownership change under Section 382 of the Internal Revenue Code for Celladon and Eiger, pre-merger net operating loss carryforwards and certain other tax attributes will be subject to limitations.

If a corporation undergoes an “ownership change” within the meaning of Section 382 of the Internal Revenue Code of 1986, as amended, or Section 382, the corporation’s net operating loss carryforwards and certain other tax attributes arising from before the ownership change are subject to limitations on use after the ownership change. In general, an ownership change occurs if there is a cumulative change in the corporation’s equity ownership by certain stockholders that exceeds fifty percentage points over a rolling three-year period. Similar rules may apply under state tax laws. The merger will result in an ownership change for Celladon and, accordingly, Celladon’s net operating loss carryforwards and certain other tax attributes will be subject to limitations on their use after the merger. The contemporaneous financing taken together with the merger is expected to limit Eiger’s net operating loss carryforwards. Additional ownership changes in the future could result in additional limitations on Celladon’s, Eiger’s and the combined organization’s net operating loss carryforwards, even if the Tax Benefit Preservation Plan adopted by the Celladon board of directors in September 2013 remains in place. Consequently, even if the combined organization achieves profitability, it may not be able to utilize a material portion of Celladon’s, Eiger’s or the combined organization’s net operating loss carryforwards and other tax attributes, which could have a material adverse effect on cash flow and results of operations.

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