ITEK Inotek Pharmaceuticals Corp. (delisted)

RISK FACTORS

An investment in our common stock involves a high degree of risk. Before deciding whether to invest in our common stock, you should consider carefully the risks described below and discussed under the sections captioned “Risk Factors” contained in the Merger Proxy, our Annual Report on Form 10-K for the year ended December 31, 2016, and any subsequent Quarterly Reports on Form 10-Q, which are incorporated by reference herein in their entirety, and which may be amended, supplemented or superseded from time to time by other reports we file the SEC in the future, together with other information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus, and in any free writing prospectus that we have authorized for use in connection with this offering. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. If any of these risks actually occurs, our business, financial condition, results of operations or business prospects could be seriously harmed. This could cause the trading price of our common stock to decline, resulting in a loss of all or part of your investment.

Risks Related To Rocket’s Financial Position

Rocket has a history of operating losses, and Rocket may not achieve or sustain profitability. Rocket anticipates that it will continue to incur losses for the foreseeable future. If Rocket fails to obtain additional funding to conduct its planned research and development effort, Rocket could be forced to delay, reduce or eliminate its product development programs or commercial development efforts.

Rocket is an early-stage gene therapy company with a limited operating history on which to base your investment decision. Gene therapy product development is a highly speculative undertaking and involves a substantial degree of risk. Rocket’s operations to date have been limited primarily to organizing and staffing its company, business planning, raising capital, acquiring and developing product and technology rights and conducting preclinical research and development activities for its product candidates. Rocket has never generated any revenue from product sales. Rocket has not obtained regulatory approvals for any of its product candidates, and has funded its operations to date through proceeds from sales of its preferred stock.

Rocket has incurred net losses since its inception. Rocket Pharmaceuticals, Ltd. incurred a net loss of $7.6 million for the year ended December 31, 2016, and a net loss of $4.2 million for the period from July 14, 2015 (Rocket Pharmaceuticals, Ltd.’s inception) to December 31, 2015. As of December 31, 2016, Rocket Pharmaceuticals, Ltd. had an accumulated deficit of $11.8 million. Substantially all of its operating losses have resulted from costs incurred in connection with its research and development programs and from general and administrative costs associated with its operations. Rocket expects to continue to incur significant expenses and operating losses over the next several years and for the foreseeable future as Rocket intends to continue to conduct research and development, clinical testing, regulatory compliance activities, manufacturing activities, and, if any of its product candidates is approved, sales and marketing activities that, together with anticipated general and administrative expenses, will likely result in Rocket incurring significant losses for the foreseeable future. Rocket’s prior losses, combined with expected future losses, have had and will continue to have an adverse effect on Rocket’s stockholders’ deficit and working capital.

Rocket may need to raise additional funding, which may not be available on acceptable terms, or at all. Failure to obtain this necessary capital when needed may force Rocket to delay, limit or terminate certain of its licensing activities, product development efforts or other operations.

Rocket expects to require substantial future capital in order to seek to broaden licensing of its gene therapy platforms, complete preclinical and clinical development for its current product candidates and other future product candidates, if any, and potentially commercialize these product candidates. Rocket expects its spending levels to increase in connection with its preclinical and clinical trials. In addition, if Rocket obtains marketing approval for any of its product candidates, Rocket expects to incur significant expenses related to product sales,

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medical affairs, marketing, manufacturing and distribution. Furthermore, Rocket expects to incur additional costs associated with operating as a public company. Accordingly, Rocket will need to obtain substantial additional funding in connection with its continuing operations. If Rocket is unable to raise capital when needed or on acceptable terms, Rocket could be forced to delay, reduce or eliminate certain of its licensing activities, its research and development programs or other operations.

Rocket Pharmaceuticals, Ltd.’s operations have consumed significant amounts of cash since inception. As of December 31, 2016, Rocket Pharmaceuticals, Ltd.’s cash was $9.5 million. As of September 30, 2017 Rocket Pharmaceuticals, Ltd.’s cash was $24.2 million. Rocket’s future capital requirements will depend on many factors, including:

Many of these factors are outside of Rocket’s control. Identifying potential product candidates and conducting preclinical testing and clinical trials is a time-consuming, expensive and uncertain process that takes years to complete, and Rocket may never generate the necessary data or results required to obtain regulatory and marketing approval and achieve product sales. In addition, Rocket’s product candidates, if approved, may not achieve commercial success. Accordingly, Rocket will need to continue to rely on additional financing to achieve its business objectives.

To the extent that additional capital is raised through the sale of equity or equity-linked securities, the issuance of those securities could result in substantial dilution for Rocket’s current shareholders and the terms may include liquidation or other preferences that adversely affect the rights of Rocket’s current shareholders. Adequate additional financing may not be available to Rocket on acceptable terms, or at all. Rocket also could be required to seek funds through arrangements with partners or otherwise that may require Rocket to relinquish rights to its intellectual property, its product candidates or otherwise agree to terms unfavorable to Rocket.

Rocket’s limited operating history may make it difficult for Rocket to evaluate the success of its business to date and to assess Rocket’s future viability.

Rocket’s operations to date have predominantly focused on organizing and staffing its company, business planning, raising capital, acquiring its technology, administering and expanding its gene therapy platforms,

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identifying potential product candidates, undertaking research, preclinical studies and clinical trials of its product candidates and establishing licensing arrangements and collaborations. Rocket has not yet completed clinical trials of its product candidates, obtained marketing approvals, manufactured a commercial-scale product or conducted sales and marketing activities necessary for successful commercialization. Consequently, any predictions made about Rocket’s future success or viability may not be as accurate as they could be if Rocket had a longer operating history.

In addition, as a new business, Rocket may encounter unforeseen expenses, difficulties, complications, delays and other known and unknown factors. Rocket expects to eventually transition from a company with a licensing and research focus to a company that is also capable of supporting clinical development activities and Rocket may need to transition to supporting commercial activities in the future. Rocket cannot guarantee that it will be successful in these transitions.

Rocket’s ability to use its net operating loss carryforwards and certain other tax attributes may be limited.

Under Section 382 of the Internal Revenue Code of 1986, as amended, if a corporation undergoes an “ownership change,” generally defined as a greater than 50% change (by value) in its equity ownership over a three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards, or NOLs, and other pre-change tax attributes to offset its post-change income may be limited. Rocket may experience ownership changes in the future. As a result, if Rocket earns net taxable income, Rocket’s ability to use its pre-change net operating loss carryforwards to offset U.S. federal taxable income may be subject to limitations, which could potentially result in increased future tax liability to Rocket. Furthermore, Rocket’s ability to use net operating loss carryforwards to offset U.S. federal taxable income in the future may be further limited by certain provisions set forth in The Tax Cuts and Jobs Act, which could potentially result in increased future tax liability to Rocket. In addition, at the state level, there may be periods during which the use of NOLs is suspended or otherwise limited, which could accelerate or permanently increase state taxes owed. At December 31, 2016, Rocket Pharmaceuticals, Ltd. had net operating losses of approximately $7.0 million for New York City tax purposes. As of December 31, 2016, Rocket had no unrecognized tax benefits or liabilities for uncertain tax positions. Rocket files income tax returns in the United States and New York State and New York City, but for the year ended December 31, 2016 did not report any income effectively connected with a U.S. trade or business.

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

Rocket’s ability to generate revenue and achieve profitability depends on Rocket’s ability, alone or with strategic collaboration partners, to successfully complete the development of, and obtain the regulatory, pricing and reimbursement approvals necessary to commercialize its product candidates. Rocket does not anticipate generating revenues from product sales for the foreseeable future, if ever. Rocket’s ability to generate future revenues from product sales depends heavily on its success in:

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Even if one or more of the product candidates that Rocket will develop is approved for commercial sale, Rocket anticipates incurring significant costs associated with commercializing any approved product candidate. Rocket’s expenses could increase beyond expectations if Rocket is required by the FDA, the EMA, or other regulatory agencies, domestic or foreign, to perform clinical and other studies in addition to those that Rocket currently anticipates. Even if Rocket is able to generate revenues from the sale of any approved products, Rocket may not become profitable and may need to obtain additional funding to continue operations.

Risks Related To Product Regulatory Matters

Rocket’s gene therapy product candidates are based on novel technology, which makes it difficult to predict the time and cost of product candidate development and subsequently obtaining regulatory approval. Currently, only a few gene therapy product has been approved in the United States and the European Union.

Rocket has concentrated its research and development efforts to date on a gene therapy platform, and Rocket’s future success depends on the successful development of viable gene therapy product candidates. Rocket cannot guarantee that it will not experience problems or delays in developing current or future product candidates or that such problems or delays will not cause unanticipated costs, or that any such development problems or delays can be resolved. Rocket may also experience unanticipated problems or delays in developing Rocket’s manufacturing capacity or transferring Rocket’s manufacturing process to commercial partners, which may prevent Rocket from completing its clinical studies or commercializing its products on a timely or profitable basis, if at all.

In addition, the clinical study requirements of the FDA, the European Medicines Agency, or the EMA and other regulatory agencies and the criteria these regulators use to determine the safety and efficacy of a product candidate vary substantially according to the type, complexity, novelty and intended use and market of the potential products. The regulatory approval process for novel product candidates such as Rocket’s can be more expensive and take longer than for other, better known or more extensively studied pharmaceutical or other product candidates. Currently, only a few gene therapy products have received marketing authorization in the U.S. or the European Union, including Novartis Pharmaceuticals’ Kymriah, Kite Pharma’s Yescarta, and Spark Therapeutics’ Luxturna. It is therefore difficult to determine how long it will take or how much it will cost to obtain regulatory approvals for Rocket’s product candidates in the United States, the European Union or other jurisdictions. Approvals by the EMA may not be indicative of what the FDA may require for approval. Delay or failure to obtain, or unexpected costs in obtaining, the regulatory approvals necessary to bring a potential product to market could decrease Rocket’s ability to generate sufficient product revenue and Rocket’s business, financial condition, results of operations and prospects could be materially harmed.

Regulatory requirements governing gene therapy products have evolved and may continue to change in the future. For example, the FDA’s Center for Biologics Evaluation and Research, or CBER, which may require Rocket to perform additional nonclinical studies or clinical trials that may increase Rocket’s development costs, lead to changes in regulatory positions and interpretations, delay or prevent approval and commercialization of Rocket’s gene therapy product candidates or lead to significant post-approval limitations or restrictions.

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Rocket may encounter substantial delays in commencement, enrollment or completion of Rocket’s clinical trials or may fail to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities, which could prevent Rocket from commercializing its current and future product candidates on a timely basis, if at all.

Before obtaining marketing approval from regulatory authorities for the sale of Rocket’s current and future product candidates, Rocket must conduct extensive clinical trials to demonstrate the safety and efficacy of Rocket’s product candidates. Clinical trials are expensive, time-consuming, and outcomes are uncertain.

To date, Rocket’s experience with clinical trials has been limited. Rocket’s only clinical programs to date have been performed under a physician-sponsored investigational new drug application, or IND, held by the Fred Hutchinson Cancer Research Center in Seattle, Washington, or Hutch, and under an Investigational Medicinal Product Dossier, or IMPD, in Spain sponsored by CIEMAT. The clinical trials performed by these sponsors are for a lentiviral treatment for Fanconi Anemia, a rare mutation of the FANC-A gene, which are still ongoing. Rocket intends to assume responsibility for or obtain the authority to reference the clinical trials performed under one or both of the IND and IMPD held by its collaborators, but has not completed any clinical trials to date. Rocket cannot guarantee that any clinical trials will be conducted as planned or completed on schedule, if at all. A clinical trial failure can occur at any stage of testing.

Identifying and qualifying patients to participate in clinical trials of Rocket’s product candidates is critical to Rocket’s success. Rocket may not be able to identify, recruit and enroll a sufficient number of patients, or those with required or desired characteristics, to complete clinical trials in a timely manner. Patient enrollment and trial completion is affected by numerous factors including:

In particular, each of the conditions for which Rocket plans to evaluate its current product candidates are rare genetic diseases with limited patient pools from which to draw for clinical studies. Additionally, the process of finding and diagnosing patients may prove costly. Finally, the treatment process requires that the cells be obtained from patients and then shipped to a transduction facility within the required timelines, and this may introduce unacceptable shipping-related delays to the process.

In addition, to the extent Rocket seeks to obtain regulatory approval for its product candidates in foreign countries, Rocket’s ability to successfully initiate, enroll and complete a clinical study in any foreign country is subject to numerous risks unique to conducting business in foreign countries, including:

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If Rocket has difficulty enrolling a sufficient number of patients to conduct its clinical trials as planned, Rocket may need to delay, limit or terminate planned clinical trials, the occurrence of any of which would harm our business, financial condition, results of operations and prospects. Moreover, Rocket intends to rely on the nonclinical studies and clinical trials performed by Hutch and CIEMAT, and the FDA or the regulatory authority in any other country in which we decide to perform clinical trials or seek approval may not accept that results of the Hutch and CIEMAT studies and trials. Any inability to successfully complete preclinical studies and clinical trials could result in additional costs to Rocket or impair Rocket’s ability to generate revenues from product sales, regulatory and commercialization milestones and royalties.

Rocket has not completed any clinical studies of its current product candidates. Initial results in Rocket’s ongoing clinical studies may not be indicative of results obtained when these studies are completed. Furthermore, success in early clinical studies may not be indicative of results obtained in later studies.

Rocket’s Fanconi Anemia gene therapy treatments are currently in clinical trials being conducted by Rocket’s partners, Hutch and CIEMAT. Several of Rocket’s other gene therapy programs are in the preclinical stages. Study designs and results from previous or ongoing studies and clinical trials are not necessarily predictive of future study or clinical trial results, and initial or interim results may not continue or be confirmed upon completion of the study or trial. Positive data may not continue or occur for subjects in Rocket’s clinical studies or for any future subjects in Rocket’s ongoing or future clinical studies, and may not be repeated or observed in ongoing or future studies involving Rocket’s product candidates. Furthermore, Rocket’s product candidates may also fail to show the desired safety and efficacy in later stages of clinical development despite having successfully advanced through initial clinical studies. Rocket cannot guarantee that any of these studies will ultimately be successful or that preclinical or early stage clinical studies will support further clinical advancement or regulatory approval of Rocket’s product candidates.

Data obtained from preclinical and clinical activities are subject to varying interpretations, which may delay, limit or prevent regulatory approval. In addition, regulatory delays or rejections may be encountered as a result of many factors, including changes in regulatory policy during the period of product development .

Even if Rocket successfully completes the necessary preclinical studies and clinical trials, Rocket cannot predict when, or if, Rocket will obtain regulatory approval to commercialize a product candidate and the approval may be for a more narrow indication than Rocket seeks.

Rocket cannot commercialize a product candidate until the appropriate regulatory authorities have reviewed and approved the product candidate. Rocket has not received approval from regulatory authorities in any jurisdiction to market any of its product candidates. Even if Rocket’s product candidates meet their safety and efficacy endpoints in clinical trials, the regulatory authorities may not complete their review processes in a timely manner, issue a complete response letter, or ultimately, Rocket may not be able to obtain regulatory approval. In addition, Rocket may experience delays or rejections if an FDA Advisory Committee recommends disapproval or restrictions on use. In addition, Rocket may experience delays or rejections based upon additional government regulation from future legislation or administrative actions, or changes in regulatory authority policy during the period of product development, clinical trials and the review process. Regulatory authorities have substantial discretion in the approval process and may refuse to accept any application or may decide that Rocket’s data are

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insufficient for approval and require additional preclinical, clinical or other studies. In addition, varying interpretations of data obtained from preclinical and clinical testing could delay, limit or prevent the receipt of marketing approval for a product candidate.

Regulatory authorities also may approve a product candidate for more limited indications than requested or they may impose significant limitations in the form of narrow indications, warnings or Risk Evaluation and Mitigation Strategies, or REMS. These regulatory authorities may require precautions or contra-indications with respect to conditions of use or they may grant approval subject to the performance of costly post-marketing clinical trials. In addition, regulatory authorities may not approve the labeling claims that are necessary or desirable for the successful commercialization of Rocket’s product candidates. Any of the foregoing scenarios could materially harm the commercial prospects for Rocket’s product candidates and materially harm its business, financial condition, results of operations and prospects.

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

Even if Rocket obtains regulatory approval in a jurisdiction, the applicable regulatory authority may still impose significant restrictions on the indicated uses or marketing of Rocket’s product candidates, or impose ongoing requirements for potentially costly post-approval studies, post-market surveillance or patient or drug restrictions. Additionally, the holder of an approved Biologics License Application, or BLA is obligated to monitor and report adverse events and any failure of a product to meet the specifications in the BLA. The holder of an approved BLA must also submit new or supplemental applications and obtain FDA approval for certain changes to the approved product, product labeling or manufacturing process. FDA guidance advises that patients treated with some types of gene therapy undergo follow-up observations for potential adverse events for as long as 15 years. Advertising and promotional materials must comply with FDA rules and are subject to FDA review, in addition to other potentially applicable federal and state laws.

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 for compliance with good manufacturing practices, or GMP, and current good tissue practice, or cGMP, adherence to commitments made in the BLA. If Rocket 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 Rocket fails to comply with applicable regulatory requirements following approval of any of its product candidates, a regulatory agency may take a variety of actions, including:

Any government investigation of alleged violations of law could require Rocket to expend significant time and resources in response and could generate negative publicity. The occurrence of any event or penalty

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described above may inhibit Rocket’s ability to commercialize its product candidates and generate revenues and could harm its business, financial condition, results of operations and prospects.

In addition, the FDA’s policies, and those of comparable foreign regulatory authorities, may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of Rocket’s product candidates. Rocket cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative actions, either in the U.S. or abroad. If Rocket is slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if Rocket is not able to maintain regulatory compliance, Rocket may lose any marketing approval which Rocket may have obtained and Rocket may not achieve or sustain profitability, which would materially harm Rocket’s business, financial condition, results of operations and prospects.

Rocket may never obtain FDA approval for any of its product candidates in the United States, and even if Rocket does, Rocket may never obtain approval for or commercialize any of its product candidates in any other jurisdiction, which would limit Rocket’s ability to realize its full market potential.

In order to eventually market any of Rocket’s product candidates in any particular foreign jurisdiction, Rocket must establish and comply with numerous and varying regulatory requirements regarding safety and efficacy on a jurisdiction-by-jurisdiction basis. Approval by the FDA in the United States, if obtained, does not ensure approval by regulatory authorities in other countries or jurisdictions. In addition, preclinical studies and clinical trials conducted in one country may not be accepted by regulatory authorities in other countries, and regulatory approval in one country does not guarantee regulatory approval in any other country. Approval processes vary among countries and can involve additional product testing and validation and additional administrative review periods. Seeking foreign regulatory approval could result in difficulties and costs for Rocket and require additional preclinical studies or clinical trials which could be costly and time-consuming. Regulatory requirements can vary widely from country to country and could delay or prevent the introduction of Rocket’s products in those countries. The foreign regulatory approval process involves similar risks to those associated with FDA approval. Rocket does not have any product candidates approved for sale in any jurisdiction, including international markets, nor has Rocket attempted to obtain such approval. If Rocket fails to comply with regulatory requirements in international markets or to obtain and maintain required approvals, or if regulatory approvals in international markets are delayed, Rocket’s target market will be reduced and Rocket’s ability to realize the full market potential of its products will be unrealized.

Rocket’s product candidates may cause undesirable and unforeseen side effects or be perceived by the public as unsafe, which could delay or prevent their advancement into clinical trials or regulatory approval, limit the commercial potential or result in significant negative consequences.

Gene therapy is still a relatively new approach to disease treatment and adverse side effects could develop with Rocket’s product candidates. There also is the potential risk of delayed adverse events following exposure to gene therapy products due to persistent biologic activity of the genetic material or other components of products used to carry the genetic material.

Possible adverse side effects that could occur with treatment with gene therapy products include an immunologic reaction soon after administration which could substantially limit the effectiveness and durability of the treatment. If certain side effects are observed in testing of Rocket’s potential product candidates, Rocket may decide or be required to halt or delay further clinical development of its product candidates.

In addition to side effects caused by the product candidate, the administration process or related procedures associated with a given product candidate also can cause adverse side effects. If any such adverse events occur, Rocket’s clinical trials could be suspended or terminated. Under certain circumstances, the FDA, the European Commission, the EMA or other regulatory authorities could order Rocket to cease further development of, or deny approval of, Rocket’s product candidates for any or all targeted indications. Moreover, if Rocket elects, or

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is required, to not initiate or to delay, suspend or terminate any future clinical trial of any of its product candidates, the commercial prospects of such product candidates may be harmed and Rocket’s ability to generate product revenues from any of these product candidates may be delayed or eliminated. Any of these occurrences may harm Rocket’s ability to develop other product candidates, and may harm Rocket’s business, financial condition and prospects significantly.

Furthermore, if undesirable side effects caused by Rocket’s product candidate are identified following regulatory approval of a product candidate, several potentially significant negative consequences could result, including:

Any of these occurrences may harm Rocket’s business, financial condition and prospects significantly.

Rocket may be unable to obtain orphan drug designation or exclusivity for some product candidates. If Rocket’s competitors are able to obtain orphan drug exclusivity for products that constitute the same drug and treat the same indications as its product candidates, Rocket may not be able to have competing products approved by the applicable regulatory authority for a significant period of time.

Regulatory authorities in some jurisdictions, including the U.S. and the European Union, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act of 1983, the FDA may designate a product candidate as an orphan drug if it is intended to treat a rare disease or condition, which is generally defined as having a patient population of fewer than 200,000 individuals in the U.S., or a patient population greater than 200,000 in the U.S. where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the U.S. In the European Union, following the opinion of the EMA’s Committee for Orphan Medicinal Products, the European Commission 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, orphan designation is granted for products intended for the diagnosis, prevention or treatment of a life-threatening, seriously debilitating or serious and chronic condition and 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 biologic product.

Generally, if a product candidate with an orphan drug designation receives the first marketing approval for the indication for which it has such designation, the product is entitled to a period of marketing exclusivity, which precludes the FDA or the European Commission from approving another marketing application for a product that constitutes the same drug treating the same indication for that marketing exclusivity period, except in limited circumstances. If another sponsor receives such approval before Rocket does (regardless of Rocket’s orphan drug designation), Rocket will be precluded from receiving marketing approval for Rocket’s product for the applicable exclusivity period. The applicable period is seven years in the U.S. and 10 years in the European Union. The exclusivity period in the U.S. can be extended by six months if the BLA sponsor submits pediatric data that fairly respond to a written request from the FDA for such data. The exclusivity period in the European Union can be reduced to six years if a product no longer meets the criteria for orphan drug designation or if the product is sufficiently profitable so that market exclusivity is no longer justified. Orphan drug exclusivity may be revoked if any regulatory agency determines that the request for designation was materially defective or if the manufacturer is unable to assure sufficient quantity of the product to meet the needs of patients with the rare disease or condition.

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Even if Rocket requests orphan drug designation for any of its product candidates, Rocket cannot guarantee that the FDA or the European Commission will grant any of its product candidates such designation. Additionally, the designation of any of Rocket’s product candidates as an orphan product does not guarantee that any regulatory agency will accelerate regulatory review of, or ultimately approve, that product candidate, nor does it limit the ability of any regulatory agency to grant orphan drug designation to product candidates of other companies that treat the same indications as Rocket’s product candidates prior to Rocket’s product candidates receiving exclusive marketing approval.

Even if Rocket obtains orphan drug exclusivity for a product candidate, that exclusivity may not effectively protect the product candidate from competition because different drugs can be approved for the same condition. In the U.S., even after an orphan drug is approved, the FDA may subsequently approve another drug for the same condition if the FDA concludes that the latter drug is not the same drug or is clinically superior in that it is shown to be safer, more effective or makes a major contribution to patient care. In the European Union, marketing authorization may be granted to a similar medicinal product for the same orphan indication if:

Risks Related To Manufacturing, Development and Commercialization Of Rocket’s Product Candidates

Products intended for use in gene therapies are novel, complex and difficult to manufacture. Rocket could experience production problems that result in delays in its development or commercialization programs, limit the supply of its products or otherwise harm its business.

Rocket currently has development, manufacturing and testing agreements with third parties to manufacture supplies of its product candidates. Several factors could cause production interruptions, including equipment malfunctions, facility contamination, raw material shortages or contamination, natural disasters, disruption in utility services, human error or disruptions in the operations of suppliers.

Rocket’s product candidates require processing steps that are more complex than those required for small molecule pharmaceuticals.

Rocket may encounter problems contracting with, hiring and retaining the experienced scientific, quality control and manufacturing personnel needed to operate Rocket’s manufacturing process which could result in delays in Rocket’s production or difficulties in maintaining compliance with applicable regulatory requirements.

Any problems in Rocket’s manufacturing process or the facilities with which Rocket contracts could make Rocket a less attractive collaborator for potential partners, including larger pharmaceutical companies and academic research institutions, which could limit Rocket’s access to attractive development programs. Problems in third-party manufacturing processes or facilities also could restrict Rocket’s ability to meet market demand for Rocket’s products. Additionally, should Rocket manufacturing agreements with third parties be terminated for any reason, there may be a limited number of manufacturers who would be suitable replacements and it could take a significant amount of time to transition the manufacturing to a replacement.

Rocket may not successfully commercialize Rocket’s drug candidates.

Rocket’s gene therapy product candidates are subject to the risks of failure inherent in the development of pharmaceutical products based on new technologies, and Rocket’s failure to develop safe, commercially viable

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products would severely limit Rocket’s ability to become profitable or to achieve significant revenues. Rocket may be unable to successfully commercialize Rocket’s product candidates because of several reasons, including:

Rocket’s ability to successfully develop and commercialize its product candidates will substantially depend upon the availability of reimbursement funds for the costs of the resulting drugs and related treatments.

Market acceptance and sales of Rocket’s product candidates may depend on coverage and reimbursement policies and health care reform measures. Decisions about formulary coverage as well as levels at which government authorities and third-party payors, such as private health insurers and health maintenance organizations, reimburse patients for the price they pay for Rocket’s products as well as levels at which these payors pay directly for Rocket’s products, where applicable, could affect whether Rocket is able to successfully commercialize these products. Rocket cannot guarantee that reimbursement will be available for any of its product candidates. Nor can Rocket guarantee that coverage or reimbursement amounts will not reduce the demand for, or the price of, its product candidates. Rocket has not commenced efforts to have its product candidates reimbursed by government or third-party payors. If coverage and reimbursement are not available or are available only at limited levels, Rocket may not be able to successfully commercialize its products. In March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or the PPACA, was signed into law, and in recent years, numerous proposals to change the health care system in the U.S. have been made. These reform proposals include measures that would limit or prohibit payments for certain medical treatments or subject the pricing of drugs to government control. In addition, in many foreign countries, particularly the countries of the European Union, the pricing of prescription drugs is subject to government control. If Rocket’s products are or become subject to government regulation that limits or prohibits payment for Rocket’s products, or that subjects the price of Rocket’s products to governmental control, Rocket may not be able to generate revenue, attain profitability or commercialize its products.

In addition, third-party payors are increasingly limiting both coverage and the level of reimbursement of new drugs. They may also impose strict prior authorization requirements and/or refuse to provide any coverage of uses of approved products for medical indications other than those for which the FDA has granted market approvals. As a result, significant uncertainty exists as to whether and how much third-party payors will reimburse patients for their use of newly-approved drugs. If Rocket is unable to obtain adequate levels of reimbursement for its product candidates, Rocket’s ability to successfully market and sell its product candidates will be harmed. The manner and level at which reimbursement is provided for services related to Rocket’s product candidates (e.g., for administration of Rocket’s product to patients) is also important to successful commercialization of its product candidates. Inadequate reimbursement for such services may lead to physician resistance and limit Rocket’s ability to market or sell its products.

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

Rocket is engaged in gene therapy for severe genetic and rare diseases, which is a competitive and rapidly changing field. Rocket has competitors both in the United States and internationally, including major

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multinational pharmaceutical companies, biotechnology companies and universities and other research institutions.

Many of Rocket’s competitors may have substantially greater financial, technical and other resources, such as larger research and development staff, manufacturing capabilities, experienced marketing and manufacturing organizations. Rocket’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 Rocket may develop, or achieve earlier patent protection, regulatory approval, product commercialization and market penetration than Rocket. Additionally, technologies developed by Rocket’s competitors may render its potential product candidates uneconomical or obsolete, and Rocket may not be successful in marketing Rocket’s product candidates against those of Rocket’s competitors.

In addition, as a result of the expiration or successful challenge of Rocket’s patent rights, Rocket could face increased litigation with respect to the validity and/or scope of patents relating to Rocket’s competitors’ products. The availability of Rocket’s competitors’ products could limit the demand, and the price Rocket is able to charge, for any products that Rocket may develop and commercialize, thereby causing harm to Rocket’s business, financial condition, results of operations and prospects.

Rocket may not be successful in its efforts to build a pipeline of additional product candidates.

Rocket’s business model is centered on applying its expertise in rare genetic diseases by establishing focused selection criteria to develop and advance a portfolio of gene therapy product candidates through development into commercialization. Rocket may not be able to continue to identify and develop new product candidates in addition to the pipeline of product candidates that its research and development efforts to date have resulted in. Even if Rocket is successful in continuing to build Rocket’s pipeline, the potential product candidates that Rocket identifies may not be suitable for clinical development. If Rocket does not successfully develop and commercialize product candidates based upon its approach, Rocket will not be able to obtain product revenue in future periods, which would likely result in significant harm to Rocket’s financial position and results of operations.

The success of Rocket’s research and development activities, upon which Rocket primarily focuses, is uncertain.

Rocket’s primary focus is on its research and development activities and the clinical testing and commercialization of its product candidates. Research and development was Rocket’s most significant operating expense for the year ended December 31, 2016. Research and development activities, by their nature, preclude definitive statements as to the time required and costs involved in reaching certain objectives. Actual research and development costs, therefore, could significantly exceed budgeted amounts and estimated time frames may require significant extension. Cost overruns, unanticipated regulatory delays or demands, unexpected adverse side effects or insufficient therapeutic efficacy will prevent or substantially slow Rocket’s research and development effort and Rocket’s business could ultimately suffer. Rocket anticipates that it will remain principally engaged in research and development activities for an indeterminate, but substantial, period of time.

Risks Related To Third Parties

Rocket relies on third parties to conduct its preclinical studies and clinical trials and perform other tasks for Rocket. If these third parties do not successfully carry out their contractual duties, meet expected deadlines, or comply with regulatory requirements, Rocket may not be able to obtain regulatory approval for or commercialize Rocket’s product candidates and Rocket’s business, financial condition and results of operations could be substantially harmed.

Rocket has relied upon and plans to continue to rely upon third parties, including contract research organizations, which we refer to as CROs, medical institutions, and contract laboratories to monitor and manage

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data for Rocket’s ongoing preclinical and clinical programs. Nevertheless, Rocket maintains responsibility for ensuring that each of Rocket’s clinical trials and preclinical studies is conducted in accordance with the applicable protocol, legal, regulatory, and scientific standards and Rocket’s reliance on these third parties does not relieve Rocket of its regulatory responsibilities. Rocket and its vendors are required to comply with current requirements on GMP, good clinical practices, or GCP, and good laboratory practice, or GLP, which are a collection of laws and regulations enforced by the FDA, EMA or comparable foreign authorities for all of Rocket’s drug candidates in clinical development.

Regulatory authorities enforce these regulations through periodic inspections of preclinical study and clinical trial sponsors, principal investigators, preclinical study and clinical trial sites, and other contractors. If Rocket or any of its vendors fails to comply with applicable regulations, the data generated in Rocket’s preclinical studies and clinical trials may be deemed unreliable and the FDA, EMA or comparable foreign authorities may require Rocket to perform additional preclinical studies and clinical trials before approving Rocket’s marketing applications. Rocket cannot assure you that upon inspection by a given regulatory authority, such regulatory authority will determine that any of Rocket’s clinical trials comply with GCP regulations. In addition, Rocket’s clinical trials must be conducted with products produced consistent with GMP regulations. Rocket’s failure to comply with these regulations may require Rocket to repeat clinical trials, which would delay the development and regulatory approval processes.

If any of Rocket’s relationships with these third parties, medical institutions, clinical investigators or contract laboratories terminate, Rocket may not be able to enter into arrangements with alternative CROs on commercially reasonable terms, or at all. In addition, Rocket’s CROs are not its employees, and except for remedies available to Rocket under its agreements with such CROs, Rocket cannot control whether or not they devote sufficient time and resources to Rocket’s ongoing preclinical and clinical programs. If Rocket’s CROs do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the data they obtain is compromised due to the failure to adhere to Rocket’s protocols, regulatory requirements, or for other reasons, Rocket’s clinical trials may be extended, delayed or terminated and Rocket may not be able to obtain regulatory approval for or successfully commercialize its product candidates. CROs may also generate higher costs than anticipated. As a result, Rocket’s business, financial condition and results of operations and the commercial prospects for Rocket’s product candidates could be materially and adversely affected, Rocket’s costs could increase, and its ability to generate revenue could be delayed.

Switching or adding additional CROs, medical institutions, clinical investigators or contract laboratories involves additional cost and requires management time and focus. In addition, there is a natural transition period when a new CRO commences work replacing a previous CRO. As a result, delays occur, which can materially impact Rocket’s ability to meet its desired clinical development timelines. Though Rocket carefully manages its relationships with its CROs, Rocket cannot guarantee that Rocket will not encounter similar challenges or delays in the future or that these delays or challenges will not have a material adverse effect on its business, financial condition or results of operations.

Rocket expects to rely on third parties to conduct some or all aspects of its drug product manufacturing, research and preclinical and clinical testing, and these third parties may not perform satisfactorily.

Rocket does not expect to independently conduct all aspects of its gene therapy production, product manufacturing, research and preclinical and clinical testing. Rocket currently relies, and expects to continue to rely, on third parties with respect to these items. In some cases these third parties are academic, research or similar institutions that may not apply the same quality control protocols utilized in certain commercial settings.

Rocket’s reliance on these third parties for research and development activities will reduce Rocket’s control over these activities but will not relieve Rocket of its responsibility to ensure compliance with all required regulations and study protocols. If these third parties do not successfully carry out their contractual duties, meet

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expected deadlines or conduct Rocket’s studies in accordance with regulatory requirements or Rocket’s stated study plans and protocols, Rocket will not be able to complete, or may be delayed in completing, the preclinical and clinical studies required to support future product submissions and approval of its product candidates.

Generally these third parties may terminate their engagements with Rocket at will upon notice. If Rocket needs to enter into alternative arrangements, it could delay Rocket’s product development activities.

Reliance on third-party manufacturers entails risks to which Rocket would not be subject if Rocket manufactured the product candidates itself, including:

Any of these events could lead to clinical study delays or failure to obtain regulatory approval, or impact Rocket’s ability to successfully commercialize future products. Some of these events could be the basis for FDA action, including an injunction, recall, seizure or total or partial suspension of production.

Rocket may not be successful in finding strategic collaborators for continuing development of certain of its product candidates or successfully commercializing its product candidates.

Rocket may seek to establish strategic partnerships for developing and/or commercializing certain of Rocket’s product candidates due to relatively high capital costs required to develop the product candidates, manufacturing constraints or other reasons. Rocket may not be successful in its efforts to establish such strategic partnerships or other alternative arrangements for its product candidates for several reasons, including because its research and development pipeline may be insufficient, Rocket’s product candidates may be deemed to be at too early of a stage of development for collaborative effort or third parties may not view Rocket’s product candidates as having the requisite potential to demonstrate efficacy or market opportunity. In addition, Rocket may be restricted under existing agreements from entering into future agreements with potential collaborators.

If Rocket is unable to reach agreements with suitable licensees or collaborators on a timely basis, on acceptable terms or at all, Rocket may have to curtail the development of a product candidate, reduce or delay its development program, delay its potential commercialization, reduce the scope of any sales or marketing activities or increase Rocket’s expenditures and undertake development or commercialization activities at its own expense. If Rocket elects to independently fund development or commercialization activities, Rocket may need to obtain additional expertise and additional capital, which may not be available on acceptable terms or at all. If Rocket fails to enter into collaboration arrangements and does not have sufficient funds or expertise to undertake necessary development and commercialization activities, Rocket may not be able to further develop its product candidates and Rocket’s business, financial condition, results of operations and prospects may be materially harmed.

The commercial success of any of Rocket’s product candidates will depend upon its degree of market acceptance by physicians, patients, third-party payors and others in the medical community.

Ethical, social, legal and other concerns about gene therapy could result in additional regulations restricting or prohibiting Rocket’s products. Even with the requisite approvals from the FDA in the United States, the EMA

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in the European Union and other regulatory authorities internationally, the commercial success of Rocket’s product candidates will depend, in part, on the acceptance of physicians, patients and health care payors of gene therapy products in general, and Rocket’s product candidates in particular, as medically beneficial, cost-effective and safe. Any product that Rocket commercializes may not gain acceptance by physicians, patients, health care payors and others in the medical community. If these products do not achieve an adequate level of acceptance, Rocket may not generate significant product revenue and may not become profitable. The degree of market acceptance of gene therapy products and, in particular, Rocket’s product candidates, if approved for commercial sale, will depend on several factors, including:

Even if a potential product displays a favorable efficacy and safety profile in preclinical studies and clinical trials, market acceptance of the product will not be fully known until after it is approved and launched. The failure of any of Rocket’s product candidates to achieve market acceptance could materially harm Rocket’s business, financial condition, results of operations and prospects.

RTW Investments, LLC, Rocket’s principal stockholder, may have the ability to significantly influence all matters submitted to stockholders for approval.

RTW Investments, LLC (“RTW”), in the aggregate, beneficially owns approximately 46.68% of our outstanding shares of common stock. This concentration of voting power gives RTW the power to significantly influence all matters submitted to our stockholders for approval, as well as our management and affairs. For example, RTW could significantly influence the election of directors and approval of any merger, consolidation or sale of all or substantially all of our assets.

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Risks Related To Personnel and Other Risks Related To Rocket’s Business

Rocket’s business could suffer if it loses the services of, or fails to attract, key personnel.

Rocket is highly dependent upon the efforts of the company’s senior management, including Rocket’s Chief Executive Officer, Gaurav Shah, MD; and Rocket’s Chief Medical Officer and Head of Development, Jonathan Schwartz, MD. The loss of the services of these individuals and other members of Rocket’s senior management could delay or prevent the achievement of research, development, marketing, or product commercialization objectives. Rocket’s employment arrangements with the key personnel are “at-will.” Rocket does not maintain any “key-man” insurance policies on any of the key employees nor does Rocket intend to obtain such insurance. In addition, due to the specialized scientific nature of Rocket’s business, Rocket is highly dependent upon its ability to attract and retain qualified scientific and technical personnel and consultants. In view of the stage of Rocket’s organizational development and research and development programs, Rocket has restricted its hiring to research scientists, consultants and a small administrative staff and has made only limited investments in manufacturing, production, sales or regulatory compliance resources. There is intense competition among major pharmaceutical and chemical companies, specialized biotechnology firms and universities and other research institutions for qualified personnel in the areas of Rocket’s operations, however, and Rocket may be unsuccessful in attracting and retaining these personnel.

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

As of December 4, 2017, Rocket had less than 20 full-time employees. As Rocket’s business activities expand, Rocket may expand its full-time employee base and hire more consultants and contractors. Rocket’s management may need to divert a disproportionate amount of its attention away from day-to-day activities and devote a substantial amount of time to managing these growth activities. Rocket may not be able to effectively manage the expansion of its operations, which may result in weaknesses in Rocket’s infrastructure, operational setbacks, loss of business opportunities, loss of employees and reduced productivity among remaining employees. Rocket’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 Rocket’s management is unable to effectively manage Rocket’s growth, Rocket’s expenses may increase more than expected, Rocket’s ability to generate and/or grow revenues could be reduced and Rocket may not be able to implement its business strategy.

Rocket’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.

Rocket is exposed to the risk of fraud or other misconduct by its employees, consultants and commercial partners. Misconduct by these parties could include intentional failures 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 and regulations in the United States and abroad, report financial information or data accurately or disclose unauthorized activities to Rocket. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations 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 clinical studies, which could result in regulatory sanctions and cause serious harm to Rocket’s reputation or could cause regulatory agencies not to approve Rocket’s product candidates. Rocket has a code of business ethics and conduct applicable to all employees, but it is not always possible to identify and deter employee or third-party misconduct, and the precautions Rocket takes to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting Rocket from governmental

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investigations or other actions or lawsuits stemming from a failure to comply with these laws or regulations. If any such actions are instituted against Rocket, and Rocket is not successful in defending the company or asserting its rights, those actions could have a significant impact on Rocket’s business, including the imposition of significant fines or other sanctions.

Rocket’s internal computer systems, or those of its third-party collaborators or other contractors, may fail or suffer security breaches, which could result in a material disruption of Rocket’s development programs.

Rocket’s internal computer systems and those of its current and any future collaborators and other consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. While Rocket 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 Rocket’s operations, it could result in a material disruption of Rocket’s development programs and its business operations, whether due to a loss of its trade secrets or other proprietary information or other similar disruptions. For example, the loss of clinical trial data from completed or future clinical trials could result in delays in Rocket’s regulatory approval efforts and significantly increase Rocket’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, Rocket’s data or applications, or inappropriate disclosure of confidential or proprietary information, Rocket could incur liability, its competitive position could be harmed and the further development and commercialization of Rocket’s product candidates could be delayed.

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

Rocket employs individuals who were previously employed at universities or other biotechnology or pharmaceutical companies, including its competitors or potential competitors. Although Rocket endeavors to ensure that its employees, consultants and independent contractors do not use the proprietary information or know-how of others in their work for Rocket, Rocket may be subject to claims that Rocket or its employees, consultants or independent contractors have inadvertently or otherwise used or disclosed intellectual property, including trade secrets or other proprietary information, of any of Rocket’s employee’s former employer or other third parties. Litigation may be necessary to defend against these claims. If Rocket fails in defending any such claims, in addition to paying monetary damages, Rocket may lose valuable intellectual property rights or personnel, which could adversely impact Rocket’s business. Even if Rocket is successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Given Rocket’s commercial relationships outside of the United States, in particular in the European Union, a variety of risks associated with international operations could harm its business.

Rocket engages in various commercial relationships outside the United States and Rocket may commercialize its product candidates outside of the United States. In many foreign countries, it is common for others to engage in business practices that are prohibited by U.S. laws and regulations applicable to Rocket, including the Foreign Corrupt Practices Act. Although Rocket may implement policies and procedures specifically designed to comply with these laws and policies, there can be no assurance that Rocket’s employees, contractors and agents will comply with these laws and policies. If Rocket is unable to successfully manage the challenges of international expansion and operations, Rocket’s business and operating results could be harmed.

Rocket may be, and expect that it will be to the extent Rocket commercializes its product candidates outside the United States, subject to various risks associate with operating internationally, including:

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These and related risks could materially harm Rocket’s business, financial condition, results of operations and prospects.

Risks Related To Rocket’s Intellectual Property

Rocket’s rights to intellectual property for the development and commercialization of its product candidates are subject to the terms and conditions of licenses granted to Rocket by others.

Rocket is heavily reliant upon licenses to certain patent rights and proprietary technology from third parties that are important or necessary to the development of its technology and products, including technology related to Rocket’s manufacturing process and Rocket’s gene therapy product candidates. These and other licenses may not provide exclusive rights to use such intellectual property and technology in all relevant fields of use and in all territories in which Rocket may wish to license its platform or develop or commercialize its technology and products in the future. As a result, Rocket may not be able to prevent competitors from developing and commercializing competitive products in territories not included in all of its licenses.

Licenses to additional third-party technology that may be required for Rocket’s licensing or development programs may not be available in the future or may not be available on commercially reasonable terms, or at all, which could materially harm Rocket’s business and financial condition.

In some circumstances, Rocket may not have the right to control the preparation, filing and prosecution of patent applications, or to maintain or enforce the patents, covering technology that Rocket’s license from third parties. If Rocket’s licensors fail to maintain such patents, or lose rights to those patents or patent applications, the rights Rocket has licensed may be reduced or eliminated and Rocket’s right to develop and commercialize any of its products that are the subject of such licensed rights could be impacted. In addition to the foregoing, the risks associated with patent rights that Rocket licenses from third parties will also apply to patent rights Rocket may own in the future.

Furthermore, the research resulting in certain of Rocket’s licensed patent rights and technology was funded by the U.S. government. As a result, the government may have certain rights, or march-in rights, to such patent rights and technology. When new technologies are developed with government funding, the government generally obtains certain rights in any resulting patents, including a non-exclusive license authorizing the government to use the invention for non-commercial purposes. These rights may permit the government to disclose Rocket’s confidential information to third parties and to exercise march-in rights to use or allow third parties to use Rocket’s licensed technology. The government can exercise its march-in rights if it determines that

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action is necessary because Rocket fails to achieve practical application of the government-funded technology, because action is necessary to alleviate health or safety needs, to meet requirements of federal regulations or to give preference to U.S. industry. In addition, Rocket’s rights in such inventions may be subject to certain requirements to manufacture products embodying such inventions in the U.S. Any exercise by the government of such rights could harm Rocket’s competitive position, business, financial condition, results of operations and prospects.

If Rocket is unable to obtain and maintain patent protection for is products and related technology, or if the scope of the patent protection obtained is not sufficiently broad, Rocket’s competitors could develop and commercialize products and technology similar or identical to Rocket’s, and Rocket’s ability to successfully commercialize its products may be harmed.

Rocket’s success depends, in large part, on its ability to obtain and maintain patent protection in the U.S. and other countries with respect to its product candidates and its manufacturing technology. Rocket’s licensors have sought and Rocket may intend to seek to protect its proprietary position by filing patent applications in the U.S. and abroad related to many of its novel technologies and product candidates that are important to its business.

The patent prosecution process is expensive, time-consuming and complex, and Rocket may not be able to file, prosecute, maintain, enforce or license all necessary or desirable patent applications at a reasonable cost or in a timely manner. In addition, certain patents in the field of gene therapy that may have otherwise potentially provided patent protection for certain of Rocket’s product candidates have expired or will soon expire. In some cases, the work of certain academic researchers in the gene therapy field has entered the public domain, which Rocket believes precludes its ability to obtain patent protection for certain inventions relating to such work. It is also possible that Rocket will fail to identify patentable aspects of its research and development output before it is too late to obtain patent protection.

Rocket is party to intellectual property license agreements with several entities, each of which is important to its business, and Rocket expects to enter into additional license agreements in the future. Rocket’s patent portfolio consists solely of patent applications in-licensed pursuant to those license agreements, and those agreements impose, and Rocket expects that future license agreements will impose, various diligence, development and commercialization timelines, milestone obligations, payments and other obligations on Rocket. If Rocket or its licensees fail to comply with Rocket’s obligations under these agreements, or Rocket is subject to a bankruptcy, the licensor may have the right to terminate the license, in which event Rocket could lose certain rights provided by the licenses, including that Rocket may not be able to market products covered by the license. In addition, the patent rights we have in-licensed from Hutch relate only to Hutch’s “Prodigy” platform, a portable platform for hematopoietic stem/progenitor cell gene therapy, and not to RP-L101, Rocket’s LVV-based program targeting FA that is in-licensed from Hutch.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain, involves complex legal and factual questions and has, in recent years, been the subject of much litigation. As a result, the issuance, scope, validity, enforceability and commercial value of Rocket’s patent rights are highly uncertain. Pending and future patent applications may not result in patents being issued which protect Rocket’s technology or product candidates or which effectively prevent others from commercializing competitive technologies and product candidates. Changes in either the patent laws or interpretation of the patent laws in the U.S. and other countries may diminish the value of Rocket’s patent rights or narrow the scope of Rocket’s patent protection.

While we believe our intellectual property allows us to pursue our current development programs, several companies and academic institutions are pursuing alternate approaches to gene therapy and have built intellectual property around these approaches and methods. For example, Institute Pasteur controls a patent family related to vector elements for lentiviral-based gene therapy. These patents relate to an element that improves nuclear localization. While these patents expire from 2019-2023, if our product were to launch before these dates, we

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may need to secure a license. In addition, Rocket may not be aware of all third-party intellectual property rights potentially relating to its technology and product candidates. Publications of discoveries in the scientific literature often lag the actual discoveries, and patent applications in the U.S. and other jurisdictions are typically not published until 18 months after filing or, in some cases, not at all. Therefore, Rocket cannot be certain that Rocket was the first to make the inventions claimed in any owned or any licensed patents or pending patent applications, or that Rocket was the first to file for patent protection of such inventions.

Even if the patent applications Rocket licenses or may own in the future do issue as patents, they may not issue in a form that will provide Rocket with any meaningful protection, prevent competitors or other third parties from competing with Rocket or otherwise provide Rocket with any competitive advantage. Rocket’s competitors or other third parties may avail themselves of safe harbor under the Drug Price Competition and Patent Term Restoration Act of 1984 (Hatch-Waxman Amendments) to conduct research and clinical trials and may be able to circumvent Rocket’s patent rights by developing similar or alternative technologies or products in a non-infringing manner.

The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, and Rocket’s patent rights may be challenged in the courts or patent offices in the U.S. and abroad. Such challenges may result in loss of exclusivity or in patent claims being narrowed, invalidated or held unenforceable, which could limit Rocket’s ability to stop others from using or commercializing similar or identical technology and products, or limit the duration of the patent protection of is technology and product candidates. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. As a result, Rocket’s intellectual property may not provide sufficient rights to exclude others from commercializing products similar or identical to Rocket’s.

If Rocket breaches its license agreements, it could have a material adverse effect on Rocket’s commercialization efforts for its product candidates.

If Rocket breaches any of the agreements under which Rocket licenses intellectual property relating to the use, development and commercialization rights to its product candidates or technology from third parties, Rocket could lose license rights that are important to its business. Licensing of intellectual property is of critical importance to Rocket’s business and involves complex legal, business and scientific issues. Disputes may arise between Rocket and its licensors regarding intellectual property subject to a license agreement, including:

If disputes over intellectual property that Rocket has in-licensed prevent or impair Rocket’s ability to maintain its current licensing arrangements on acceptable terms, Rocket may be unable to successfully develop and commercialize the affected product candidates. In addition, if disputes arise as to ownership of licensed

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intellectual property, Rocket’s ability to pursue or enforce the licensed patent rights may be jeopardized. If Rocket or its licensors fail to adequately protect this intellectual property, Rocket’s ability to commercialize its products could suffer.

Rocket may incur substantial costs as a result of litigation or other proceedings relating to patent and other intellectual property rights and Rocket may be unable to protect its rights to, or use, its technology.

If Rocket chooses to engage in legal action to prevent a third-party from using the inventions claimed in its patents or patents which Rocket licenses, that third-party has the right to ask the court to rule that these patents are invalid and/or should not be enforced against that third-party. These lawsuits are expensive and would consume time and other resources even if Rocket were successful in stopping the infringement of these patents. In addition, there is a risk that the court will decide that these patents are not valid and that Rocket does not have the right to stop the other party from using the inventions. There is also the risk that, even if the validity of these patents is upheld, the court will refuse to stop the other party on the ground that such other party’s activities do not infringe Rocket’s rights to these patents.

Furthermore, a third-party may claim that Rocket is using inventions covered by the third-party’s patent rights and may go to court to stop Rocket from engaging in its normal operations and activities, including making or selling its product candidates. These lawsuits are costly and could affect Rocket’s results of operations and divert the attention of managerial and technical personnel. There is a risk that a court would decide that Rocket is infringing the third-party’s patents and would order Rocket to stop the activities covered by the patents. In addition, there is a risk that a court will order Rocket to pay the other party damages for having violated the other party’s patents. The biotechnology industry has produced a proliferation of patents, and it is not always clear to industry participants which patents cover various types of products or methods of use. The coverage of patents is subject to interpretation by the courts, and the interpretation is not always uniform. If Rocket is sued for patent infringement, Rocket would need to demonstrate that its products or methods of use either do not infringe the patent claims of the relevant patent and/or that the patent claims are invalid. Proving invalidity, in particular, is difficult since it requires a showing of clear and convincing evidence to overcome the presumption of validity enjoyed by issued patents. Rocket’s competitors have filed, and may in the future file, patent applications covering technology similar to Rocket’s. Any such patent application may have priority over Rocket’s in-licensed patent applications and could further require Rocket to obtain rights to issued patents covering such technologies. If another party has filed a U.S. patent application on inventions similar to Rocket’s, Rocket may have to participate in an interference proceeding declared by the U.S. Patent and Trademark Office, to determine priority of invention in the U.S. The costs of these proceedings could be substantial, and it is possible that such efforts would be unsuccessful, resulting in a loss of Rocket’s United States patent position with respect to such inventions.

Some of Rocket’s competitors may be able to sustain the costs of complex patent litigation more effectively than Rocket can because they have substantially greater resources. In addition, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on Rocket’s ability to raise the funds necessary to continue its operations.

If Rocket is unable to protect the confidentiality of its trade secrets, its business and competitive position may be harmed.

In addition to the protection afforded by patents, Rocket relies upon unpatented trade secret protection, unpatented know-how and continuing technological innovation to develop and maintain its competitive position. Rocket seeks to protect its proprietary technology and processes, in part, by entering into confidentiality agreements with its contractors, collaborators, employees and consultants. Nonetheless, Rocket may not be able to prevent the unauthorized disclosure or use of its technical know-how or other trade secrets by the parties to these agreements, however, despite the existence generally of confidentiality agreements and other contractual restrictions. Monitoring unauthorized uses and disclosures is difficult and Rocket does not know whether the

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steps Rocket has taken to protect its proprietary technologies will be effective. If any of the contractors, collaborators, employees and consultants who are parties to these agreements breaches or violates the terms of any of these agreements, Rocket may not have adequate remedies for any such breach or violation. As a result, Rocket could lose its trade secrets. Enforcing a claim that a third-party illegally obtained and is using its trade secrets, like patent litigation, is expensive and time consuming and the outcome is unpredictable. In addition, courts outside the United States are sometimes less willing or unwilling to protect trade secrets.

Rocket’s trade secrets could otherwise become known or be independently discovered by Rocket’s competitors. Competitors could purchase Rocket’s product candidates and attempt to replicate some or all of the competitive advantages Rocket derives from its development efforts, willfully infringe Rocket’s intellectual property rights, design around Rocket’s protected technology or develop their own competitive technologies that fall outside of Rocket’s intellectual property rights. If any of Rocket’s trade secrets were to be lawfully obtained or independently developed by a competitor, Rocket would have no right to prevent them, or those to whom they communicate it, from using that technology or information to compete with Rocket. If Rocket’s trade secrets are not adequately protected or sufficient to provide an advantage over Rocket’s competitors, Rocket’s competitive position could be adversely affected, as could Rocket’s business. Additionally, if the steps taken to maintain Rocket’s trade secrets are deemed inadequate, Rocket may have insufficient recourse against third parties for misappropriating Rocket’s trade secrets.

If we are unable to obtain or protect intellectual property rights related to our product candidates, we may not be able to compete effectively in our markets.

We rely upon a combination of patents, trade secret protection and confidentiality agreements to protect the intellectual property related to our 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 we own or in-license may fail to result in issued patents with claims that cover our 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 our 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 our 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, our patents and patent applications may not adequately protect our intellectual property, provide exclusivity for our product candidates or prevent others from designing around our claims. Any of these outcomes could impair our ability to prevent competition from third parties, which may have an adverse impact on our business.

If the patent applications we hold or have in-licensed with respect to our programs or product candidates fail to issue, if their breadth or strength of protection is threatened, or if they fail to provide meaningful exclusivity for our product candidates, it could dissuade companies from collaborating with us to develop product candidates, and threaten our ability to commercialize, future products. Several patent applications covering our product candidates have been filed recently. We 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 us could deprive us of rights necessary for the successful commercialization of any product candidates that we may develop. Further, if we encounter delays in regulatory approvals, the period of time during which we 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, we cannot be certain that we were 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 our 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 affords, is limited. Even if patents covering our product

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candidates are obtained, once the patent life has expired for a product, we may be open to competition from generic medications.

In addition to the protection afforded by patents, we rely on trade secret protection and confidentiality agreements to protect proprietary know-how that is not patentable or that we elect not to patent, processes for which patents are difficult to enforce and any other elements of our 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. We seek to protect our proprietary technology and processes, in part, by entering into confidentiality agreements with our employees, consultants, scientific advisors and contractors. We also seek to preserve the integrity and confidentiality of our data and trade secrets by maintaining physical security of our premises and physical and electronic security of our information technology systems. While we have confidence in these individuals, organizations and systems, agreements or security measures may be breached, and we may not have adequate remedies for any breach. In addition, our trade secrets may otherwise become known or be independently discovered by competitors.

Although we expect all of our employees and consultants to assign their inventions to us, and all of our employees, consultants, advisors and any third parties who have access to our proprietary know-how, information or technology to enter into confidentiality agreements, we cannot provide any assurances that all such agreements have been duly executed or that our trade secrets and other confidential proprietary information will not be disclosed or that competitors will not otherwise gain access to our trade secrets or independently develop substantially equivalent information and techniques. Misappropriation or unauthorized disclosure of our trade secrets could impair our competitive position and may have a material adverse effect on our business. Additionally, if the steps taken to maintain our trade secrets are deemed inadequate, we may have insufficient recourse against third parties for misappropriating the trade secret. In addition, others may independently discover our 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 we 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, we may encounter significant problems in protecting and defending our intellectual property both in the United States and abroad. If we are unable to prevent material disclosure of the non-patented intellectual property related to our technologies to third parties, and there is no guarantee that we will have any such enforceable trade secret protection, we may not be able to establish or maintain a competitive advantage in our market, which could materially adversely affect our business, results of operations and financial condition.

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

Our commercial success depends in part on our 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, ex parte reexaminations, post-grant review, 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 we are pursuing development candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, the risk increases that our product candidates may be subject to claims of infringement of the patent rights of third parties.

Third parties may assert that we are 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 our product candidates. Because patent applications can take many years to issue, there may be currently pending patent applications which may later result in issued patents that our product candidates may infringe. In addition, third parties may obtain patents in the future and claim that use of our technologies infringes upon these patents. If any third-party patents were held by a court of competent jurisdiction to cover the manufacturing process of any of our product candidates, any molecules formed during the manufacturing process or any final product itself, the holders of any such patents may be able to block our ability to commercialize such product candidate unless we obtained a license under the applicable patents, or until such patents expire. Similarly, if any third-party patents were held by a court of competent jurisdiction to cover aspects of our formulations, processes for manufacture or methods of use, including combination therapy, the holders of any such patents may be able to block our ability to develop and commercialize the applicable product candidate unless we obtained a license or until such patent expires. In either case, such a license may not be available on commercially reasonable terms or at all.

Parties making claims against us may obtain injunctive or other equitable relief, which could effectively block our ability to further develop and commercialize one or more of our 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 our business. In the event of a successful claim of infringement against us, we may have to pay substantial damages, including treble damages and attorneys’ fees for willful infringement, pay royalties, redesign our infringing products or obtain one or more licenses from third parties, which may be impossible or require substantial time and monetary expenditure.

We may not be successful in obtaining or maintaining necessary rights to gene therapy product components and processes for our development pipeline through acquisitions and in-licenses.

Presently we have rights to the intellectual property, through licenses from third parties and under patents that we own, to develop our gene therapy product candidates. Because our programs may involve additional product candidates that may require the use of proprietary rights held by third parties, the growth of our business will likely depend in part on our ability to acquire, in-license or use these proprietary rights. In addition, our product candidates may require specific formulations to work effectively and efficiently and these rights may be held by others. We 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 we identify. 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 we may consider attractive. These established companies may have a competitive advantage over us due to their size, cash resources and greater clinical development and commercialization capabilities.

For example, we sometimes collaborate with U.S. and foreign academic institutions to accelerate our preclinical research or development under written agreements with these institutions. Typically, these institutions provide us with an option to negotiate a license to any of the institution’s rights in technology resulting from the collaboration. Regardless of such right of first negotiation for intellectual property, we may be unable to negotiate a license within the specified time frame or under terms that are acceptable to us. If we are unable to do so, the institution may offer the intellectual property rights to other parties, potentially blocking our ability to pursue our program.

In addition, companies that perceive us to be a competitor may be unwilling to assign or license rights to us. We also may be unable to license or acquire third-party intellectual property rights on terms that would allow us to make an appropriate return on our investment. If we are unable to successfully obtain rights to required third-party intellectual property rights, our business, financial condition and prospects for growth could suffer.

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If we fail to comply with our obligations in the agreements under which we license intellectual property rights from third parties or otherwise experience disruptions to our business relationships with our licensors, we could lose license rights that are important to our business.

We are a party to a number of intellectual property license agreements that are important to our business and expect to enter into additional license agreements in the future. Our existing license agreements impose, and we expect that future license agreements will impose, various diligence, milestone payment, royalty and other obligations on us. If we fail to comply with our obligations under these agreements, or we are subject to a bankruptcy, the licensor may have the right to terminate the license, in which event we would not be able to market products covered by the license.

We may need to obtain licenses from third parties to advance our research or allow commercialization of our product candidates, and we have done so from time to time. We may fail to obtain any of these licenses at a reasonable cost or on reasonable terms, if at all. In that event, we may be required to expend significant time and resources to develop or license replacement technology. If we are unable to do so, we may be unable to develop or commercialize the affected product candidates, which could harm our business significantly. We cannot provide any assurances that third-party patents do not exist which might be enforced against our current product candidates or future products, resulting in either an injunction prohibiting our sales, or, with respect to our sales, an obligation on our part to pay royalties and/or other forms of compensation to third parties.

In many cases, patent prosecution of our licensed technology is controlled solely by the licensor. If our licensors fail to obtain and maintain patent or other protection for the proprietary intellectual property we license from them, we could lose our rights to the intellectual property or our exclusivity with respect to those rights, and our competitors could market competing products using the intellectual property. In certain cases, we control the prosecution of patents resulting from licensed technology. In the event we breach any of our obligations related to such prosecution, we may incur significant liability to our licensing partners. Licensing of intellectual property is of critical importance to our business and involves complex legal, business and scientific issues and is complicated by the rapid pace of scientific discovery in our industry. Disputes may arise regarding intellectual property subject to a licensing agreement, including:

If disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on acceptable terms, we may be unable to successfully develop and commercialize the affected product candidates.

We may be involved in lawsuits to protect or enforce our patents or the patents of our licensors, which could be expensive, time-consuming and unsuccessful.

Competitors may infringe our patents or the patents of our licensors. To counter infringement or unauthorized use, we may be required to file infringement claims, which can be expensive and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours or our licensors is not valid,

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is unenforceable and/or is not infringed, or may refuse to stop the other party from using the technology at issue on the grounds that our patents do not cover the technology in question. An adverse result in any litigation or defense proceedings could put one or more of our patents at risk of being invalidated or interpreted narrowly and could put our patent applications at risk of not issuing.

Interference proceedings provoked by third parties or brought by us may be necessary to determine the priority of inventions with respect to our patents or patent applications or those of our licensors. An unfavorable outcome could require us to cease using the related technology or to attempt to license rights to it from the prevailing party. Our business could be harmed if the prevailing party does not offer us a license on commercially reasonable terms. Our defense of litigation or interference proceedings may fail and, even if successful, may result in substantial costs and distract our management and other employees. We may not be able to prevent, alone or with our licensors, misappropriation of our intellectual property rights, particularly in countries where the laws may not protect those rights as fully as in the United States.

Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our 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 our common stock.

Patent reform legislation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents.

On September 16, 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 March 16, 2013. However, it is not clear what, if any, impact the Leahy-Smith Act will have on the operation of our business. However, the Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have a material adverse effect on our business and financial condition.

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

We employ individuals who were previously employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although we try to ensure that our employees, consultants and independent contractors do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise used or disclosed intellectual property, including trade secrets or other proprietary information, of any of our employee’s former employer or other third parties. Litigation may be necessary to defend against these claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel, which could adversely impact our business. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

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

We may also be subject to claims that former employees, collaborators or other third parties have an ownership interest in our patents or other intellectual property. We have had in the past, and we may also have to

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in the future, ownership disputes arising, for example, from conflicting obligations of consultants or others who are involved in developing our product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship or ownership. If we fail in defending any such claims, in addition to paying monetary damages, we 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 our business. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees.

Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our 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. We have systems in place to remind us to pay these fees, and we employ an outside firm and rely on our 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. We employ reputable law firms and other professionals to help us 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, our competitors might be able to enter the market and this circumstance would have a material adverse effect on our business.

Issued patents covering our product candidates could be found invalid or unenforceable if challenged in court.

If we or one of our licensing partners initiated legal proceedings against a third-party to enforce a patent covering one of our product candidates, the defendant could counterclaim that the patent covering our 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 patent eligible subject matter, 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 U.S. PTO, or made a misleading statement, during prosecution. Third parties may also raise similar claims before administrative bodies in the United States or abroad, even outside the context of litigation. Such mechanisms include re-examination, post grant review, and equivalent proceedings in foreign jurisdictions (e.g., opposition proceedings). Such proceedings could result in revocation or amendment to our patents in such a way that they no longer cover our product candidates. The outcome following legal assertions of invalidity and unenforceability is unpredictable. With respect to the validity question, for example, we cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability, we would lose at least part, and perhaps all, of the patent protection on our product candidates. Such a loss of patent protection would have a material adverse impact on our business.

Changes in U.S. patent law could diminish the value of patents in general, thereby impairing our ability to protect our products.

As is the case with other biotechnology companies, our success is heavily dependent on intellectual property, particularly patents. Obtaining and enforcing patents in the biotechnology industry involve both

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technological and legal complexity, and therefore obtaining and enforcing biotechnology patents is costly, time-consuming and inherently uncertain. In addition, the United States has recently enacted and is currently implementing wide-ranging patent reform legislation. Recent U.S. Supreme Court rulings have narrowed the scope of patent protection available in certain circumstances and weakened the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents, once obtained. Depending on decisions by the U.S. Congress, the federal courts, and the U.S. PTO, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce our existing patents and patents that we might obtain in the future.

We may not be able to protect our 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 our 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. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States, or from selling or importing products made using our inventions in and into the United States or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and further, may export otherwise infringing products to territories where we have patent protection, but enforcement is not as strong as that in the United States. These products may compete with our products and our 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 relating to biotechnology products, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our proprietary rights generally. Proceedings to enforce our patent rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate and the damages or other remedies awarded, if any, may not be commercially meaningful. Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

Risks Related to this Offering

If you purchase shares in this offering, you will suffer immediate and substantial dilution.

If you purchase shares of our common stock in this offering, you will incur immediate and substantial dilution in the as adjusted net tangible book value of your stock because the price that you pay will be substantially greater than the net tangible book value per share of the shares you acquire. To the extent we raise additional capital by issuing equity securities, our stockholders will experience substantial additional dilution. For a further description of the dilution that you will experience immediately after this offering, see the section of this prospectus supplement titled “Dilution.”

We have broad discretion in the use of the net proceeds from this offering and may not use them effectively.

Our management will have broad discretion in the application of the net proceeds from this offering and could spend the proceeds in ways that do not improve our business, financial condition or results of operations or

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enhance the value of our common stock. The net proceeds from this offering are intended to be used to fund the continued development of our pipeline of gene therapies for rare diseases, enhancements to in-house manufacturing, and general corporate purposes. We may also use a portion of the net proceeds to in-license, acquire or invest in complementary businesses or products.

The failure by our management to apply these funds effectively could result in financial losses that could harm our business, cause the price of our common stock to decline and delay the development of our product candidates. Pending their use, we may invest the net proceeds from this offering in a manner that does not produce income or that loses value.

Because we do not anticipate paying any cash dividends on shares of our common stock in the foreseeable future, capital appreciation, if any, will be your sole source of gain.

We have never declared or paid cash dividends on shares of our common stock. We anticipate that we will retain our earnings, if any, for future growth and therefore do not anticipate paying cash dividends in the future. As a result, only appreciation of the price of our shares of common stock will provide a return to shareholders.

Sales of a significant number of shares of our common stock in the public markets, or the perception that such sales could occur, could depress the market price of our common stock.

Sales of a substantial number of our shares in the public markets could depress the market price of our common stock and impair our ability to raise capital through the sale of additional equity securities. We, our directors and our executive officers and certain of our stockholders have agreed not to sell, dispose of or hedge any shares or securities convertible into or exchangeable for shares of common stock during the period from the date of this prospectus supplement continuing through and including the date 90 days after the date of this prospectus supplement, subject to certain exceptions. The underwriters may, in their discretion, release the restrictions on any such shares at any time without notice. We cannot predict the effect that future sales of our common stock would have on the market price of our common stock.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully consider the risks and uncertainties described in the documents incorporated by reference in this prospectus and any prospectus supplement, as well as other information we include or incorporate by reference into this prospectus and any applicable prospectus supplement, before making an investment decision. Our business, financial condition or results of operations could be materially adversely affected by the materialization of any of these risks. The trading price of our securities could decline due to the materialization of any of these risks, and you may lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks described in the documents incorporated herein by reference, including our most recent Annual Report on Form 10-K for the year ended December 31, 2015, as amended, which is on file with the SEC and is incorporated by reference into this prospectus, and other documents we file with the SEC that are deemed incorporated by reference into this prospectus.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, including the documents that we incorporate by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as “may”, “will”, “could”, “should”, “expects”, “intends”, “plans”, “anticipates”, “believes”, “estimates”, “predicts”, “projects”, “potential”, “continue”, and similar expressions, or the negative of these terms, or similar expressions. Accordingly, these statements involve estimates, assumptions and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus, and in particular those factors referenced in the section “Risk Factors.”

This prospectus, including the sections entitled “About this Prospectus” and “Risk Factors,” contains forward-looking statements that are based on our management’s belief and assumptions and on information currently available to our management. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

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These forward-looking statements are neither promises nor guarantees of future performance due to a variety of risks and uncertainties, many of which are beyond our control, which could cause actual results to differ materially from those indicated by these forward-looking statements, including, without limitation: the possibility that we may experience slower than expected clinical site initiation or slower than expected identification and enrollment of evaluable patients; the potential for delays or problems in analyzing data or the need for additional analysis, data or patients; the potential that future pre-clinical and clinical results may not support further development of our product candidates; the potential for unexpected adverse events in the conduct of one of our clinical trials to impact our ability to continue the clinical trial or further development of a product candidate; the risk that we may encounter other unexpected hurdles or issues in the development and manufacture of our product candidates that may impact our cost, timing or progress, as well as those risks more fully discussed in the “Risk Factors” section and under “—Risks Related to Our Business” in this prospectus supplement, the section of any accompanying prospectus supplement entitled “Risk Factors” and the risk factors and cautionary statements described in other documents that we file from time to time with the SEC, specifically under “Item 1A: Risk Factors” and elsewhere in our most recent Annual Report on Form 10-K for the period ended December 31, 2015, and our Current Reports on Form 8-K.

Given these uncertainties, readers should not place undue reliance on our forward-looking statements. These forward-looking statements speak only as of the date on which the statements were made and are not guarantees of future performance. Except as may be required by applicable law, we do not undertake to update any forward-looking statements after the date of this prospectus supplement or the respective dates of documents incorporated by reference herein or therein that include forward-looking statements.

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