Item 1A. RISK FACTORS

You should carefully consider the following risk factors in evaluating our business. A number of risks could cause our actual results to differ materially from those that are indicated by forward-looking statements. Some risks relate principally to our business and the industry in which we operate. Others relate principally to the securities market and ownership of our common stock. The risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties of which we are unaware, or that we currently deem immaterial, also may become important factors that affect us. Any of the following risks could result in material adverse impacts on our business, financial condition, or results of operations. You also should consider the other information included in this Annual Report on Form 10-K as well as our other filings with the SEC.

Summary of Risk Factors

Our business is subject to numerous risks. The following is a summary of the principal risk factors described in this section:

•We have a history of losses and our future profitability is uncertain.

•We will continue to require significant funding to maintain our current level of operations and fund the further development of our vaccine candidates.

•Our existing collaboration, funding and supply agreements, including the Sanofi CLA and our APAs, do not assure success of our vaccine candidates or vaccines or that we will be able to fully fund our vaccine candidates or vaccines or our operations, and if we are unable to satisfy the performance obligations under such agreements, we may not be eligible to receive milestone payments under such agreements, the agreements may be terminated, the purchase commitments may be reduced or we may be required to refund advance payments.

•Limitations on the use of our net operating losses and other tax attributes could adversely affect our financial condition.

•Because our vaccine product development and commercialization efforts depend on new and rapidly evolving technologies we cannot be certain that our efforts will be successful.

•Clinical and preclinical development involves a lengthy and expensive process with an uncertain outcome, and the results of prior clinical trials are not necessarily predictive of our future results.

•Any difficulties or delays in the commencement or completion, or the termination or suspension, of our current or planned clinical trials could result in increased costs to us, delay or limit our ability to generate revenue or adversely affect our commercial prospects.

•We may find it difficult to enroll subjects in our clinical trials. If we encounter difficulties enrolling subjects in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

•Use of our vaccine candidates could be associated with adverse side effects, adverse events or other safety risks, which could delay or preclude approval, cause us to suspend or discontinue clinical trials, abandon a vaccine candidate, limit the commercial profile of an approved label or result in other significant negative consequences that could severely harm our business, prospects, operating results and financial condition.

•We are a biotechnology company and face significant risk in developing, manufacturing, and commercializing our products and vaccine candidates.

•We have limited marketing capabilities, and if we are unable to enter into collaborations with marketing partners or develop our own sales and marketing capability, we may not be successful in commercializing any approved products.

•Current or future regional relationships may hinder our ability to engage in larger transactions.

•We must identify vaccines for development with our technologies and establish successful third-party relationships.

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•We rely on third parties to conduct preclinical studies and clinical trials. If these third parties do not successfully carry out their contractual duties, comply with applicable regulatory requirements or meet expected deadlines, our development programs and our ability to seek or obtain regulatory approval for or commercialize our vaccine candidates may be delayed.

•We currently rely on third parties for the manufacture of our vaccine candidates for clinical development and expect to continue to rely on third parties for the foreseeable future. This reliance on third parties increases the risk that we will not have sufficient quantities of our vaccine candidates or such quantities at an acceptable cost, which could delay, prevent or impair our development or potential commercialization efforts.

•Because we depend on third parties to conduct some of our laboratory testing and clinical trials, and a significant amount of our vaccine manufacturing and distribution, we may encounter delays in or lose some control over our efforts to develop and supply products and vaccine candidates.

•Many of our competitors have significantly greater resources and experience, which may negatively impact our commercial opportunities and those of our current and future licensees.

•The regulatory approval processes of the FDA and comparable foreign authorities are lengthy, time consuming and inherently unpredictable, and if we are ultimately unable to obtain regulatory approval for our vaccine candidates, our business will be substantially harmed.

•Our business may be adversely affected if we do not successfully execute our business development initiatives.

•Servicing our 2031 Notes and our 2027 Notes requires a significant amount of cash, and we may not have sufficient cash flow resources to pay our debt.

•Our Credit Agreement contains restrictions that limit our flexibility in operating our business.

•Because our stock price has been and will likely continue to be highly volatile, the market price of our common stock may be lower or more volatile than expected.

•Litigation or regulatory investigations could have a material adverse impact on our results of operation and financial condition.

•We or the third parties upon whom we depend may be adversely affected by natural or man-made disasters or public health emergencies.

Risks Related to Our Financial Condition and Capital Requirements

We have a history of losses and our future profitability is uncertain.

Our expenses have exceeded our revenue since our formation in 1987, and our accumulated deficit at December 31, 2025 was $4.6 billion. Our revenue and expenses have historically fluctuated significantly from period to period, and we believe our revenue and expenses will continue to fluctuate in the future.For most of our history our expenses have exceeded our revenue, which may occur during most periods in the foreseeable future. Our net income (loss) for the last three fiscal years were $440.3 million of income in 2025, $187.5 million of losses in 2024, and $545.1 million of losses in 2023.

Historically, our losses have resulted predominantly from research and development expenses for our vaccine candidates, manufacturing-related expenses, expenses associated with efforts to obtain regulatory approvals, costs related to protection of our intellectual property, and other general and administrative operating expenses, a significant portion of which have been noncash. We believe our research and development expenses may substantially increase in some years as a result of continuing efforts to develop, test, manufacture and make regulatory filings for our vaccine candidates.

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As of the end of fiscal year 2025, our investment in the development and manufacture of our COVID-19 Vaccine and our vaccine candidates has been substantial. As we evolve our operating model to focus on our partnership with Sanofi, the development of our late-stage pipeline, including our CIC and stand-alone influenza vaccine candidates, leveraging our Matrix-MTM technology to drive additional partnerships and deals, and our emerging, early-stage pipeline, we expect to continue to incur significant operating expenses and anticipate significant losses over time as we seek to:

•conduct additional clinical trials and continue to seek regulatory approvals for our vaccine candidates;

•conduct preclinical studies for other potential vaccine candidates;

•evaluate commercial opportunities for the use of our Matrix-MTM adjuvant alongside vaccine antigens produced by other manufacturers; and

•maintain, expand and protect our intellectual property portfolio.

As a result, we expect our cumulative operating losses to increase until such time, if ever, that product sales, licensing fees, royalties, milestones, contract research and other sources generate sufficient revenue to fully fund our operations. We may never achieve profitability and may not sustain profitability, if achieved.

We will continue to require significant funding to maintain our current level of operations and fund the further development of our vaccine candidates.

We do not currently generate sufficient revenue from product sales, licensing fees, royalties, milestones, contract research or other sources to fully fund our operations. We, therefore, will use our cash resources, and expect to require additional funds, to maintain our operations, continue our research and development programs, advance preclinical studies and clinical trials, seek regulatory approvals and manufacture and market any of our vaccine candidates that are approved for commercialization.

To date, we have financed our operations primarily through the sale of equity and debt securities, government funding and grant agreements, non-refundable upfront payment under the Sanofi CLA, revenue from product sales, and upfront payments under APAs for our COVID-19 Vaccine. Although we have entered into APAs for our COVID-19 Vaccine that include prepayments from the purchasers, until we can generate sufficient product revenue from such agreements to fully fund our operations, which we may never do, we expect to finance our cash needs through a combination of milestone payments, royalties, and payments for transition services and technology transfer under the Sanofi CLA, revenue from product sales, additional public or private equity or debt financings, which may include at the market offerings, existing cashand cash equivalents, investments in marketable securities, potential collaborations, strategic alliances, marketing, distribution or licensing arrangements, funding from governmental and non-governmental funding entities, and potentially other sources. While we may continue to apply for contracts or grants from academic institutions, non-profit organizations and governmental entities, we may not be successful. Adequate additional funding may not be available to us on favorable terms, or at all. Furthermore, negative interpretations of clinical trial data or setbacks, or perceived setbacks, with respect to manufacturing ability and/or capacity or regulatory filing timelines for our vaccine candidates, as well as the competitive landscape posed by other vaccines, may impair our ability to raise additional financing on favorable terms, or at all. If we cannot raise the additional funds required for our anticipated operations, we may be required to delay significantly, reduce the scope of or eliminate one or more of our research or development programs, downsize our organization, or seek alternative measures to avoid insolvency, including arrangements with collaborative partners or others that may require us to relinquish rights to certain of our technologies or vaccine candidates. If we raise additional funds through future offerings of shares of our common stock or other securities, such offerings would cause dilution of current stockholders’ percentage ownership in the Company, which could be substantial. Future offerings also could have a material and adverse effect on the price of our common stock.

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Economic and political uncertainty may adversely affect our access to capital, cost of capital and ability to execute our business plan as scheduled.

Generally, worldwide economic conditions remain uncertain, particularly due to the impact of increased interest rates, and inflation. In addition, our operations and performance may be affected by changes in diplomatic and trade relationships, tariffs, trade protection measures, import or export licensing requirements, new or different customs duties, trade embargoes and sanctions and other trade barriers, political or civil unrest or military action, including conflicts between Russia and Ukraine and Israel and Hamas as well as hostilities elsewhere in the Middle East. Access to capital markets is critical to our ability to operate. Traditionally, biotechnology companies have funded their research and development expenditures by raising capital in the equity markets. Declines and uncertainties in these markets in the past have severely restricted raising new capital and have affected companies’ ability to continue to expand or fund existing development, manufacturing, regulatory and commercialization efforts. We require significant capital for our current and expected operations. The general economic and capital market conditions, both in the U.S. and worldwide, have been volatile in the past and at times have adversely affected our access to capital and increased the cost of capital. The capital and credit markets may not be available to support future capital raising activity on favorable terms. If economic conditions decline, our future cost of equity or debt capital and access to the capital markets could be adversely affected. In addition, if we are unable to access the capital markets on favorable terms, our ability to execute our business plan as contemplated would be compromised. Moreover, we rely and intend to rely on third parties, including clinical research organizations, contract manufacturing organizations and other important vendors and consultants. Global economic conditions may result in a disruption or delay in the performance of our third-party contractors and suppliers. If such third parties are unable to adequately satisfy their contractual commitments to us in a timely manner, our business could be adversely affected.

Our existing collaboration, funding and supply agreements, including the Sanofi CLA and our APAs, do not assure success of our vaccine candidates or vaccines or that we will be able to fully fund our vaccine candidates or vaccines or our operations, and if we are unable to satisfy the performance obligations under such agreements, we may not be eligible to receive milestone payments under such agreements, the agreements may be terminated, the purchase commitments may be reduced or we may be required to refund advance payments.

We have entered into, and may in the future enter into, collaboration, funding, supply and other agreements for our vaccines or vaccine candidates to help fund the development, manufacture and/or commercialization of our vaccines or vaccine candidates. Certain of these agreements may contain development, technology transfer, launch, sales and other milestones related to our vaccines or vaccine candidates pursuant to which we may be eligible to receive milestone payments upon the achievement of the requisite milestone. For example, we are eligible to receive future milestone payments under the Sanofi CLA totaling up to $350 million in the aggregate with respect to COVID-19 Vaccine products, of which $75 million remains outstanding for the completion of the technology transfer of the Company’s manufacturing process for the COVID-19 Vaccine products to Sanofi, as well as up to $350 million in CIC Product-related development and launch milestones. We may experience challenges in satisfying our obligations under these agreements, including as a result of delayed performance of our third-party contractors and suppliers, which may impact our ability to achieve such milestones, potentially expose us to damages or other liability pursuant to these agreements, including the Sanofi CLA, and have a material and adverse effect on our financial condition.

Under certain APAs, if we do not timely achieve requisite regulatory milestones for our COVID-19 Vaccine in the relevant jurisdictions, obtain supportive recommendations from governmental advisory committees, and/or achieve product volume or delivery timing obligations, purchasers may seek to terminate such agreements, reduce their purchase commitments, require us to refund all or some prepayments we have received, or renegotiate such agreements, each of which could have a material and adverse effect on our financial condition. For example, in the first quarter of 2025, the Company received written notice of a $23.0 million claim related to certain performance obligations under an APA agreement with a customer. The Company believes it has fulfilled the requirements related to this matter and is evaluating the merits of the claim. The timing to fulfill performance obligations related to supply agreements will depend on timing of product manufacturing, receipt of marketing authorizations for additional indications, delivery of doses based on customer demand, and the ability of the customer to request variant vaccine in place of COVID-19 Vaccine under certain of our supply agreements. The supply agreements typically contain terms that include upfront payments intended to assist us in funding investments related to building out and operating our manufacturing and distribution network, among other expenses, in support of our global supply commitment, and are applied to billings upon delivery of a qualifying COVID-19 Vaccine. Such upfront payments generally become non-refundable upon our achievement of certain development, regulatory and commercial milestones. We may not achieve such milestones, which could have a material and adverse effect on our financial condition.

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For example, in December 2024, we entered into an amendment to the Australia APA pursuant to which, among other things, we acknowledged the cancellation by Australia of the delivery of certain doses of our COVID-19 Vaccine scheduled for delivery between the fourth quarter of 2023 and the fourth quarter of 2025 and we agreed to credit approximately $31 million of the advanced payment paid by Australia to us against outstanding invoices and invoices for the future delivery of approximately three million doses of COVID-19 Vaccine without requiring additional cash payments. In addition, the amendment provides for certain remedies for Australia, including return of unused credit, cancellation of doses, or termination of the Australia APA, in the eventwe are unable to gain regulatory approval of a variant COVID-19 vaccine or supply doses per the terms of the agreementSpecifically, Australia did not take delivery of doses that were due to be delivered in 2025 and may seek to cancel the future delivery of the 2025 as well as 2026 doses. If we are unable to provide doses per the supply schedule as amended, after six months, Australia may seek to terminate the APA. The amendment also provides Australia with the right to cancel doses if we fail to timely notify Australia of changes to our commercialization plans. In the event that we do not, on or before the relevant contractual deadlines, receive regulatory approval for, and deliver, the seasonally updated COVID-19 Vaccine, up to $92.5 million of deferred revenue may become refundable. As of December 31, 2025, $48.4 million was classified as current Deferred revenue and $85.4 million was classified as non-current Deferred revenue with respect to the Australia APA on our consolidated balance sheet, which will be recognized in product revenue as doses are delivered to Australia. In the third quarter of 2025 we withdrew our application for our COVID-19 Vaccine based on recommendations made by the TGA. The parties are in ongoing discussions and have agreed to a meeting to discuss outstanding issues and obligations under the APA. In light of these developments, we may seek to further amend the Australian APA, which amendment may not be achievable on acceptable terms or at all.

If we fail to maintain an effective system of internal control over financial reporting, we may not be able to accurately report our financial results and current and potential stockholders may lose confidence in our financial and other public reporting, which would harm our business and have a negative effect on the trading price of our common stock.

We are required by the Sarbanes-Oxley Act of 2002 to establish and maintain adequate internal control over financial reporting that provides reasonable assurance regarding the reliability of our financial reporting and the preparation of financial statements in accordance with GAAP. We are likewise required, on an annual basis, to evaluate the effectiveness of our internal controls and to disclose on a quarterly basis any material changes in those internal controls.

As initially disclosed in Item 9A - Controls and Procedures in our Annual Report on Form 10-K for the year ended December 31, 2024, in connection with the audit of our financial statements for the year ended December 31, 2024, we identified a material weakness in our internal control over financial reporting with regard to deficiencies specifically related to ineffective change management review and periodic access review controls, with respect to our human resources information system (“HRIS”), which was implemented in 2024. As a result of the deficiencies, certain change management and user access controls, as well as the related process-level IT dependent manual controls and automated application controls across various processes impacted by the HRIS were also determined to be ineffective.

While this material weakness was remediated in 2025, we may have additional material weaknesses or significant deficiencies in our internal control over financial reporting in the future. Any failure to maintain such internal controls, or to timely remediate any additional material weaknesses or significant deficiencies in the future, could adversely impact our ability to report our financial results on a timely and accurate basis and could restrict our future access to the capital markets. If our financial statements are not accurate, investors may not have a complete understanding of our operations or may lose confidence in our reported financial information. Likewise, if our financial statements are not filed on a timely basis as required by the SEC and Nasdaq, we could face severe consequences from those authorities. In either case, it could result in a material adverse effect on our business or have a negative effect on the trading price of our common stock.

Limitations on the use of our net operating losses and other tax attributes could adversely affect our financial condition.

As of December 31, 2025, we had federal and state net operating loss (“NOL”) carryforwards of $ $2.6 billion and $824.1 million, respectively, a portion of which were generated in taxable years before December 31, 2017. Under the Tax Cuts and Jobs Act of 2017, as modified by the CARES Act, U.S. federal NOL carryforwards generated in taxable years beginning after December 31, 2017, may be carried forward indefinitely, but the deductibility of such NOL carryforwards is limited to 80% of taxable income. A portion of our NOL carryforwards (including federal NOL carryforwards generated in taxable years prior to 2018) are subject to a limited carryforward period, and if we are unable to earn sufficient income or profits to utilize these NOL carryforwards before they expire, they will not be available to offset future taxable income. To the extent that we generate future taxable losses in the United States, unused losses will carry forward to offset future taxable

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income (subject to any applicable limitations), if any. Our NOL carryforwards are subject to review and possible adjustment by the appropriate taxing authorities.

In addition, our ability to utilize our NOL carryforwards and other tax attributes to offset future taxable income or tax liabilities may be limited as a result of certain ownership changes. Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended (the “Code”), our federal NOL carryforwards and other tax attributes may become subject to an annual limitation in the event of certain cumulative changes in our ownership that constitute an “ownership change” pursuant to Section 382 of the Code. An “ownership change” pursuant to Section 382 of the Code generally occurs if one or more stockholders or groups of stockholders who own at least 5% of a company’s stock increase their ownership by more than 50 percentage points over their lowest ownership percentage within a rolling three-year period. Similar provisions of state tax law may also apply to limit the use of our state NOL carryforwards. We may have experienced ownership changes in the past and could experience ownership changes in the future, including as a result of future changes in our stock ownership, some of which changes may be outside our control.

For these reasons, we may not be able to realize a tax benefit from the use of our NOL carryforwards and certain other tax attributes, whether or not we attain or maintain profitability. If our ability to use our NOL carryforwards or other tax attributes is limited or deferred, we may incur greater than expected tax liabilities and cash outflows, which could adversely affect our results of operations, liquidity, and overall financial condition. As of December 31, 2025, we maintain a full valuation allowance over our deferred tax assets for financial reporting purposes.

Risks Related to Product Development and Commercialization

Because our vaccine product development and commercialization efforts depend on new and rapidly evolving technologies, our efforts may not succeed.

Our vaccine development efforts depend on new, rapidly evolving technologies and on the marketability and profitability of our current and future products. The payments received from Sanofi for their commercialization of our COVID-19 Vaccine and the development and, if successful, commercialization efforts of our other vaccine candidates could fail for a variety of reasons, including if:

•our recombinant nanoparticle vaccine technologies, any or all of the products based on such technologies or our proprietary manufacturing process prove ineffective or unsafe;

•we or our third-party manufacturer facilities fail to reproducibly scale-up and maintain manufacturing with sufficiently high yields at reasonable cost and on projected timelines, or such manufacturing fails to generate product that consistently satisfies purity, potency, quality, stability, and shelf-life standards necessary for obtaining regulatory approvals or achieving commercial viability;

•the products are uneconomical to market or manufacture;

•some or all of the products that we or our third-party partners have manufactured may be determined to be unsalable based on criteria imposed by regulators in connection with potential regulatory approvals;

•our in-house or third-party manufacturing facilities fail regulatory inspections;

•proprietary rights of third-parties prevent us or our collaborators from exploiting technologies, and manufacturing or marketing products; or

•third-party competitors achieve and maintain greater market share due to earlier approvals or superior marketing capabilities.

Clinical and preclinical development involves a lengthy and expensive process with an uncertain outcome, and the results of prior clinical trials are not necessarily predictive of our future results.

Clinical and preclinical development is expensive and can take many years to complete, and its outcome is inherently uncertain. We cannot guarantee that any preclinical studies or clinical trials will be conducted as planned or completed on schedule, if at all, and failure can occur at any time during the trial or study process. Despite promising

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preclinical or clinical results, any vaccine candidate can unexpectedly fail at any stage of preclinical or clinical development. The historical failure rate for vaccine candidates in our industry is high, particularly in the early stages of development.

The results from preclinical studies or clinical trials of a vaccine candidate or a competitor’s vaccine candidate in the same class may not predict the results of later clinical trials of such vaccine candidate, and interim, topline, or preliminary results of a clinical trial are not necessarily indicative of final results. Vaccine candidates in later stages of clinical trials may fail to show the desired safety and efficacy characteristics despite having progressed through preclinical studies and initial clinical trials. It is not uncommon to observe results in clinical trials that are unexpected based on preclinical studies and early clinical trials. Many vaccine candidates fail in clinical trials despite very promising early results, and a number of companies in the biopharmaceutical and biotechnology industries have suffered significant setbacks in clinical development even after achieving promising results in earlier preclinical studies and clinical trials.

Based upon negative or inconclusive results, we or any future collaborator may decide, or regulators may require us, to conduct additional preclinical studies or clinical trials, which would cause us to incur additional operating expenses. In addition, if our collaborators conduct clinical trials that generate negative results or results that conflict with the results of our clinical trials, the FDA or other regulatory authorities may delay, limit, or deny approval of our vaccine candidates, require us to conduct additional clinical trials as a condition to regulatory approval. As a result, we cannot be certain that our planned preclinical studies and clinical trials will be successful. Any safety concerns observed in any one of our clinical trials in our targeted indications could limit the prospects for regulatory approval of our vaccine candidates, which could have a material adverse effect on our business, financial condition and results of operations.

In addition, the FDA’s and other regulatory authorities’ policies with respect to clinical trials may change and additional government regulations may be enacted. For instance, the regulatory landscape related to clinical trials in the EU recently evolved. The EU Clinical Trials Regulation (“CTR”), which was adopted in April 2014 and repeals the EU Clinical Trials Directive, became applicable on January 31, 2022. While the EU Clinical Trials Directive required a separate clinical trial application (“CTA”), to be submitted in each member state in which the clinical trial takes place, to both the competent national health authority and an independent ethics committee, the CTR introduces a centralized process and only requires the submission of a single application for multi-center trials. The CTR allows sponsors to make a single submission to both the competent authority and an ethics committee in each member state, leading to a single decision per member state. The assessment procedure of the CTA has been harmonized as well, including a joint assessment by all member states concerned, and a separate assessment by each member state with respect to specific requirements related to its own territory, including ethics rules. Each member state’s decision is communicated to the sponsor via the centralized EU portal. Once the CTA is approved, clinical study development may proceed. The CTR transition period ended on January 31, 2025, and all clinical trials (and related applications) are now fully subject to the provisions of the CTR. Furthermore, on April 28, 2025, the UK adopted an amendment to the Medicines for Human Use (Clinical Trials) Regulations 2004 intended to support a more streamlined and flexible regulation of clinical trials, removing unnecessary administrative burdens on trial sponsors, whilst protecting the interests of trial participants. It also intends to bring the UK regulatory framework for clinical trials, which is still based on the EU Clinical Trials Directive, into closer alignment with the CTR. The amendment will become applicable on April 28, 2026 following a one-year transition period. If we, or our third-party providers, such as CRO, are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies governing clinical trials, our development plans may be impacted.

Any difficulties or delays in the commencement or completion, or the termination or suspension, of our current or planned clinical trials could result in increased costs to us, delay or limit our ability to generate revenue or adversely affect our commercial prospects.

Before obtaining regulatory approval from regulatory authorities for the sale of our vaccine candidates, we must conduct extensive clinical trials to demonstrate the safety, purity, potency, immunogenicity and efficacy of the vaccine candidates in humans. Before we can initiate clinical trials for our vaccine candidates, we must submit the results of preclinical studies to the FDA or comparable foreign regulatory authorities along with other information, including information about vaccine candidate chemistry, manufacturing and controls and our proposed clinical trial protocol, as part of an Investigational New Drug Application (“IND”) to the FDA or as part of any similar regulatory submission required for allowance to proceed with clinical development. The FDA or comparable foreign regulatory authorities may require us to conduct additional preclinical studies, or added clinical evaluation under any IND, clinical trial application or similar regulatory submission, which may lead to delays and increase the costs of our clinical development program. Moreover, even if we commence clinical trials, issues may arise that could cause regulatory authorities to suspend or terminate such clinical trials. Any such delays in the commencement or completion of our preclinical studies and planned clinical trials for our vaccine candidates could significantly affect our product development timelines and product development costs.

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We do not know whether our planned clinical trials will begin on time or be completed on schedule, if at all. The commencement, data readouts and completion of clinical trials can be delayed for a number of reasons, including delays related to:

•inability to generate sufficient preclinical, toxicology, or other in vivo or in vitro data to support the initiation or continuation of clinical trials;

•obtaining regulatory authorizations or allowances to commence a trial or reaching a consensus with regulatory authorities on trial design;

•the FDA or comparable foreign regulatory authorities disagreeing as to the implementation of our clinical trials;

•any failure or delay in reaching an agreement with contract research organizations (“CROs”) and clinical trial sites, the terms of which can be subject to extensive negotiation and may vary significantly among different CROs and trial sites;

•delays in identifying, recruiting and training suitable clinical investigators;

•obtaining approval from one or more institutional review boards (“IRBs”) or ethics committees at clinical trial sites;

•IRBs refusing to approve, suspending or terminating the trial at an investigational site, precluding enrollment of additional subjects, or withdrawing their approval of the trial;

•major changes or amendments to the clinical trial protocol;

•clinical sites deviating from the trial protocol or dropping out of a trial;

•failure by our CROs to perform in accordance with good clinical practice (“GCP”) requirements or applicable regulatory guidelines in other countries;

•manufacturing sufficient quantities of our vaccine candidates and placebo for use in clinical trials, which could be materially impacted by supply chain disruption or other issues;

•expiration of the shelf life of clinical material for use in clinical trials prior to the enrollment of any of our clinical trials;

•subjects failing to enroll or remain in our trials at the rate we expect, or failing to return for post-treatment follow-up, including subjects failing to remain in our trials;

•insufficient incidence of infection with the applicable disease or condition that would allow us to evaluate the endpoints in our clinical trials of our vaccine candidates;

•individuals choosing an alternative product for the indication for which we are developing our vaccine candidates, or participating in competing clinical trials;

•lack of adequate funding to continue the clinical trial;

•subjects experiencing severe or serious unexpected vaccine-related adverse effects;

•occurrence of vaccine-related serious adverse events in trials of other vaccine candidates conducted by other companies that could be considered similar to our vaccine candidates;

•selection of clinical endpoints that require prolonged periods of clinical observation or extended analysis of the resulting data;

•transfer of manufacturing processes to larger-scale facilities operated by a contract manufacturing organization (“CMO”), delays or failure by our CMOs or us to make any necessary changes to such manufacturing process, or failure of our CMOs to produce clinical trial materials in accordance with current good manufacturing practice (“cGMP”) regulations or other applicable requirements; and

•third parties being unwilling or unable to satisfy their contractual obligations to us in a timely manner.

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We could also encounter delays if a clinical trial is suspended or terminated by us, by the IRBs of the institutions in which such trials are being conducted, by a Data Safety Monitoring Board for such trial or by the FDA or comparable foreign regulatory authorities. Such authorities may impose such a suspension or termination due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or comparable foreign regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a vaccine, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. In addition, changes in regulatory requirements and policies may occur, and we may need to amend clinical trial protocols to comply with these changes. Amendments may require us to resubmit our clinical trial protocols to IRBs for reexamination, which may impact the costs, timing or successful completion of a clinical trial.

Further, conducting clinical trials in foreign countries, as we have in the past and may do for our vaccine candidates, presents additional risks that may delay completion of our clinical trials. These risks include the failure of enrolled subjects in foreign countries to adhere to clinical protocols as a result of differences in healthcare services or cultural customs, managing additional administrative burdens associated with foreign regulatory schemes, and political and economic risks, including war, relevant to such foreign countries.

In addition, many of the factors that cause, or lead to, the termination or suspension of, or a delay in the commencement or completion of, clinical trials may also ultimately lead to the denial of regulatory approval of a vaccine candidate. We may make formulation or manufacturing changes to our vaccine candidates, in which case we may need to conduct additional preclinical studies to bridge our modified vaccine candidates to earlier versions. Any resulting delays to our clinical trials could shorten any period during which we may have the exclusive right to commercialize our vaccine candidates. In such cases, our competitors may be able to bring products to market before we do, and the commercial viability of our vaccine candidates could be significantly reduced. Any of these occurrences may harm our business, financial condition and prospects.

We may find it difficult to enroll subjects in our clinical trials. If we encounter difficulties enrolling subjects in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

Successful and timely completion of clinical trials will require that we identify and enroll a specified number of subjects for each of our clinical trials. We may not be able to initiate or continue clinical trials for our vaccine candidates if we are unable to identify and enroll a sufficient number of eligible subjects to participate in these trials as required by the FDA or similar regulatory authorities outside the United States.

Subject enrollment, a significant factor in the timing of clinical trials, is affected by many factors, including the size and nature of the subject population, the risks and severity associated the disease under investigation, the proximity of subjects to clinical sites, the eligibility and exclusion criteria for the trial, the design of the clinical trial, the ability to obtain and maintain informed consents, the ability to co-administer a vaccine candidate with other vaccines, the risk that enrolled subjects will not complete a clinical trial, our ability to recruit clinical trial investigators with the appropriate competencies and experience, and competing clinical trials and clinicians’ and subjects’ perceptions as to the potential advantages and risks of the vaccine candidate being studied in relation to other available vaccines or therapies, including any new products that may be approved for the indications we are investigating as well as any vaccine candidates under development.

We cannot assure you that our assumptions used in determining expected clinical trial timelines are correct or that we will not experience delays in enrollment, which would result in the delay of completion of such trials beyond our expected timelines.

Use of our vaccine candidates could be associated with adverse side effects, adverse events or other safety risks, which could delay or preclude approval, cause us to suspend or discontinue clinical trials, abandon a vaccine candidate, limit the commercial profile of an approved label or result in other significant negative consequences that could severely harm our business, prospects, operating results and financial condition.

Results of our clinical trials could reveal a high and unacceptable severity and prevalence of expected or unexpected side effects. Vaccine-related side effects could affect subject recruitment or the ability of enrolled subjects to complete the trial or result in potential product liability claims. Undesirable side effects caused by our vaccine candidates when used alone or in combination with approved drugs, biologics or vaccines could cause us or regulatory authorities to interrupt, delay or halt clinical trials and could result in a more restrictive label or lead to the delay or denial of regulatory approval by the FDA or comparable foreign regulatory authorities. For example, in October 2024, the U.S. FDA placed a clinical hold on the IND for our CIC and stand-alone influenza vaccine candidates from a spontaneous report of a serious adverse event in a

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participant who received the CIC vaccine candidate in a Phase 2 trial that completed in 2023. After providing the FDA with the requested additional information, this event was assessed as not related to vaccination. The information provided to the FDA supported our assessment that the serious adverse event was not related to our CIC vaccine candidate, and the FDA removed the clinical hold in November 2024. Any of these occurrences could severely harm our business, prospects, operating results and financial condition.

Moreover, if our vaccine candidates are associated with undesirable side effects in clinical trials or demonstrate characteristics that are unexpected, we may elect to abandon their development or limit their development to more narrow uses or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective, which may limit the commercial expectations for the vaccine candidate if approved. We may also be required to modify our development and clinical trial plans based on findings after we commence clinical trials. Many compounds that initially showed promise in early-stage testing have later been found to cause side effects that prevented further development of the compounds. In addition, regulatory authorities may draw different conclusions or require additional testing to confirm these determinations.

It is possible that as we test our vaccine candidates in larger, longer and more extensive clinical trials, or if the use of these vaccine candidates becomes more widespread following regulatory approval, more illnesses, injuries, discomforts and other adverse events than were observed in earlier trials, as well as new conditions that did not occur or went undetected, may be discovered. If such side effects become known later in development or upon approval, if any, such findings may harm our business, financial condition and prospects significantly.

In addition, if our vaccine candidates receive regulatory approval, and we or others later identify undesirable side effects caused by such vaccine, a number of potentially significant negative consequences could result, including:

•regulatory authorities may withdraw, suspend or limit approvals of such vaccine or seek an injunction against its manufacture or distribution;

•we may be required to recall a vaccine or change the way such vaccine is administered to individuals;

•regulatory authorities may require additional warnings on the label, such as a “black box” warning or a contraindication;

•we may be required to implement a Risk Evaluation and Mitigation Strategy (“REMS”) or create a medication guide outlining the risks of such side effects for distribution to individuals;

•we may be required to change the way a vaccine is distributed or administered, conduct additional clinical trials or change the labeling of a vaccine or be required to conduct additional post-marketing studies or surveillance;

•we could be sued and held liable for harm caused to vaccine recipients;

•sales of the vaccine may decrease significantly or the vaccine could become less competitive; and

•our reputation may suffer.

Any of these events could prevent us from achieving or maintaining market acceptance of the particular vaccine candidate, if approved, and could significantly harm our business, results of operations and prospects.

Interim, “topline” and preliminary data from our clinical trials and preclinical studies that we announce or publish from time to time may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publicly disclose interim, topline, or preliminary data from our clinical trials and preclinical studies, which is based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the interim, topline, or preliminary results that we report may differ from future results of the same studies or trials, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Topline and preliminary data also remain subject to audit and verification procedures that may result in the final data being materially different from the topline or

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preliminary data we previously published. As a result, topline and preliminary data should be viewed with caution until the final data are available.

Interim data from clinical trials are further subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available. Adverse differences between interim, topline, or preliminary data and final data could significantly harm our business prospects. Further, disclosure of such data by us or by our competitors could result in volatility in the price of our common stock.

Further, others, including regulatory agencies, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular vaccine candidate or product and our company in general. In addition, the information we choose to publicly disclose regarding a particular study or clinical trial is based on what is typically extensive information, and you or others may not agree with what we determine is material or otherwise appropriate information to include in our disclosure, and any information we determine not to disclose may ultimately be deemed significant with respect to future decisions, conclusions, views, activities or otherwise regarding a particular vaccine candidate or our business. If the interim, topline, or preliminary data that we report differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, our vaccine candidates may be harmed, which could harm our business, operating results, prospects or financial condition.

The emergence and transmissibility of variants of the SARS-CoV-2 virus may affect market acceptance or sales of our COVID-19 Vaccine.

As the SARS-CoV-2 virus continues to evolve, new strains of the virus, or those that are already in circulation, have in the past (in the cases of the Alpha, Beta, Delta and Omicron, including subvariants such as XBB.1.5 and JN.1, variants) and may in the future prove more transmissible or cause more severe forms of COVID-19 disease than the predominant strains to date.

Our 2026 revenue depends on Sanofi’s ability to successfully manufacture, distribute, and market in accordance with the Sanofi CLA, an updated monovalent formulation of our COVID-19 Vaccine, marketed as NuvaxovidTM in the U.S., for the 2025-2026 vaccination season. This product may not be as effective in protecting against these or other future variant strains, and it may fail to achieve market acceptance or significant sales, despite gaining any regulatory approval, which may lead to reputational harm, loss of market share, and adverse financial results.

Further, counterparties to certain of our existing APAs may request variant-specific vaccines in place of our COVID-19 Vaccine and, depending on when we are able to offer such variant-specific vaccines, if at all, such counterparties may seek to delay, reduce or otherwise renegotiate their purchase commitments, which may adversely impact our ability to realize the full financial benefit of such APAs.

We are a biotechnology company and face significant risk in developing, manufacturing and commercializing our products.

We focus our research and development activities on vaccines, an area in which we believe we have particular strengths and a technology that appears promising. The outcome of any research and development program is highly uncertain. Only a small fraction of biopharmaceutical development programs ultimately result in commercial products or even vaccine candidates and a number of events could delay our development efforts and negatively impact our ability to make regulatory submissions or obtain regulatory approval for, and to manufacture, market and sell, our vaccine candidates or any other vaccine on our projected timelines, if at all. Vaccine candidates that initially appear promising often fail to yield successful products, and we may not ultimately be able to demonstrate the safety, potency, purity, stability and efficacy necessary to obtain or maintain regulatory authorization to market our vaccine candidates. In many cases, preclinical studies or clinical trials will show that a vaccine candidate is not efficacious or that it raises safety concerns or has other side effects that outweigh its intended benefit. Success in preclinical or early clinical trials may not translate into success in large-scale clinical trials. Further, success in clinical trials often leads to increased investment, accelerating cumulative losses. Even if clinical trial results appear positive, regulatory approval may not be obtained if the FDA, or a foreign equivalent, does not agree with our interpretation of the results. Even after a product is approved and launched, general usage or post-marketing clinical trials may identify safety or other previously unknown problems with the product, or manufacturing issues may emerge, either of which may result in regulatory approvals being suspended, limited to narrow the scope of the approval, or revoked, which may otherwise prevent successful commercialization. Intense competition in the vaccine industry could also limit the successful commercialization of any products for which we receive commercial approval.

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We will require approval from the FDA of any name we intend to use for our products regardless of whether we have secured a trademark registration from the USPTO. The FDA typically conducts a review of proposed product names, including an evaluation of potential for confusion with other product names. The FDA may object to any product name we submit if it believes the name inappropriately implies medical claims. If the FDA objects to any of our proposed product names, we may be required to adopt an alternative name for our proposed products. If we adopt an alternative name, we would lose the benefit of any existing trademark applications for such developmental candidate and may be required to expend significant additional resources in an effort to identify a suitable product name that would qualify under applicable trademark laws, not infringe the existing rights of third parties and be acceptable to the FDA. We may be unable to build a successful brand identity for a new trademark in a timely manner or at all, which would limit our ability to commercialize our products, if approved.

We may have product liability exposure.

The administration of drugs or vaccines to humans, whether in clinical trials or after marketing approval, can result in product liability claims. We maintain product liability insurance coverage for our current clinical programs, and for commercialization of NuvaxovidTM. However, we may not be able to obtain additional insurance coverage or maintain insurance coverage on commercially reasonable terms, at a reasonable cost or in sufficient amounts to protect us against losses due to liability. Furthermore, such insurance coverage and our resources may not be sufficient to satisfy all liabilities that result from product liability claims. A successful claim may prevent us from obtaining adequate product liability insurance in the future on commercially desirable terms, if at all. Even if a claim is not successful, defending such a claim would be time-consuming and expensive, may damage our reputation in the marketplace and would likely divert management’s attention.

In addition, regardless of any authorizations we have received supporting the development or commercialization of our vaccine candidates, unexpected safety issues could lead to product liability claims and our existing insurance may not be adequate for such claims.

Regardless of merit or eventual outcome, liability claims may result in:

•decreased demand for our products;

•withdrawal of regulatory authorizations and approvals;

•voluntary or mandatory recalls of our products;

•necessity for additional nonclinical or clinical studies, changes in labeling, or changes to manufacturing processes, specifications and/or facilities;

•impairment of our business reputation and negative media attention;

•withdrawal of clinical trial participants;

•costs of related litigation;

•substantial monetary awards to participants or other claimants;

•loss of revenue; and

•inability to commercialize our vaccine candidates.

In addition, in the United States, the Public Readiness and Emergency Preparedness Act (the “PREP Act”), when applicable, provides immunity for manufacturers from all claims under state or federal law for “loss” arising out of the administration or use of a “covered countermeasure.” However, injured persons may still bring a suit for “willful misconduct” against the manufacturer under some circumstances. “Covered countermeasures” include “security countermeasures,” “qualified pandemic or epidemic products,” which include products intended to diagnose or treat pandemic or epidemic disease, such as pandemic vaccines and treatments intended to address conditions caused by such products, and drugs and biological products authorized for emergency use in accordance with sections 564, 564A, and 564B of the FDCA. For these immunities to apply, the Secretary of DHHS must invoke the PREP Act by issuing a declaration that

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a public health emergency or “credible risk” of a future public health emergency exists. On March 17, 2020, the Secretary of DHHS issued a declaration under the PREP Act for medical countermeasures against COVID-19, effective as of February 4, 2020, and has issued subsequent amendments since then to provide liability immunity for activities related to certain countermeasures against the ongoing COVID-19 pandemic. On December 11, 2024, the Secretary of DHHS issued the 12th amendment to the PREP Act declaration to extend time period of PREP Act coverage to December 31, 2029. While we believe our products are Covered Countermeasures under the current PREP Act declaration, coverage cannot be assured. Further, it remains possible that the HHS Secretary will amend the PREP Act declaration for medical countermeasures against COVID-19 to, among other things, shorten the duration of its coverage. Certain members of Congress have also sought to amend or repeal the PREP Act in effort to restrict or eliminate PREP Act immunity. As a result, the PREP Act, and any associated immunity, remains subject to significant uncertainty.

Even if we successfully commercialize any of our vaccine candidates, either alone or in collaboration, we face uncertainty with respect to pricing, third-party reimbursement and healthcare reform, all of which could be subject to change and could adversely affect any commercial success of our vaccine candidates.

Our ability to collect revenue from the commercial sale of our vaccines may depend on our ability, and that of any current or potential future collaboration partners or customers, to obtain and if obtained, maintain adequate levels of approval, coverage and reimbursement for such products from third-party payers including: government health administration authorities such as the Advisory Committee for Immunization Practices of the Centers for Disease Control and Prevention (“ACIP”), private health insurers, managed care organizations, pharmacy benefit management companies, and other healthcare related organizations.

Third-party payers are increasingly challenging the prices charged for medical products and may deny coverage or offer inadequate levels of reimbursement if they determine that a product has not received appropriate clearances from the FDA, or foreign equivalent, or other government regulators; is not used in accordance with cost-effective treatment methods as determined by the third-party payer; or is experimental, unnecessary or inappropriate. Prices could also be driven down by managed care organizations that control or significantly influence utilization of healthcare products.

In both the U.S. and some foreign jurisdictions, there have been a number of legislative and regulatory proposals and initiatives to change the health care system in ways that could affect our ability to sell vaccines and could adversely affect the prices that we receive for our vaccine candidates, if approved. Some of these proposed and implemented reforms could result in reduced drug pricing or reimbursement rates for medical products. The impact of such reform could adversely affect our business strategy, operations and financial results. Our exposure to price-related regulation could depend on whether our products are reimbursed by Medicare under Part B or Part D. Medicare Part B vaccine coverage includes vaccines to prevent influenza, pneumococcal disease, hepatitis B for beneficiaries who are at medium or high risk, and COVID-19. Vaccines for such conditions do not have any cost-sharing requirements. Meanwhile, Medicare Part D vaccine coverage includes all other commercially available vaccines that are determined to be reasonable and necessary to prevent illness. Part D vaccine coverage historically included cost-sharing requirements, but, effective January 1, 2023, the IRA provides access to CDC and ACIP-recommended vaccines covered under Medicare Part D without cost-sharing.

Recommendation by ACIP of a vaccine has significant impacts on the coverage and reimbursement of the vaccine from commercial and governmental payers, such as Medicaid and Medicare. For example, vaccines that receive ACIP recommendations benefit from enhanced coverage requirements under the Affordable Care Act, the Inflation Reduction Act, and the Social Security Act, among other statutes. ACIP’s recommendations therefore directly influence coverage and reimbursement decisions by governments and private payers, in turn influencing healthcare providers and individual decision making. Similarly, the absence or withdrawal of an ACIP recommendation for a vaccine can result in increased beneficiary cost-sharing obligations and absence or limitations of coverage and reimbursement.

For example, under the Trump administration, the COVID-19 vaccine for healthy children and healthy pregnant women was removed from the CDC recommended immunization schedules, and the DHHS Secretarial Directives ratifying CDC recommendations for use of COVID-19 vaccines for children ages six months to 17 years were rescinded. Currently, CDC recommends a 2025-2026 COVID-19 vaccine for people ages 6 months and older based on individual-based decision-making, noting that parents of children ages 6 months to 17 years should discuss the benefits of vaccination with a healthcare provider. CDC states that it is especially important to get a 2025–2026 COVID-19 vaccine for individuals aged 65 and older, individuals at high risk for severe COVID-19, or individuals who have never received a COVID-19 vaccine. It is possible that ACIP may withdraw or further limit its recommendation for COVID-19 vaccines. The revised CDC recommendations, as well as any possible future negative actions by ACIP regarding vaccination schedules, may adversely affect demand for our vaccine candidates and have material adverse effects on our business and results of operations.

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We cannot predict the ultimate content, timing or effect of any healthcare reform legislation or the impact of potential legislation on us. We also cannot predict if the Trump administration’s policies might adversely impact funding for vaccine research and development, reimbursement for vaccines and their administration, vaccine mandates and recommendations, and public perception of vaccine importance. The U.S. Department of Health and Human Services (“DHHS”) Secretary Robert F. Kennedy Jr. has populated ACIP with members who generally have voiced negative views regarding COVID-19 vaccines. The FDA’s Vaccines and Related Biological Products Advisory Committee makes recommendations to FDA regarding novel vaccine products, and the Trump administration has so far removed at least one member from the committee. It is possible that further changes to the composition of the committee could result in additional adverse recommendations that negatively affect the development and commercialization of our vaccine candidates.

The Trump administration’s changes to the immunization schedule for children and adolescents and vaccine recommendations to date, and similar changes that could be adopted in the future, could, among other things, result in adverse recommendations from ACIP or delay ACIP decisions or other elements of the approval pathway, potentially adversely impacting vaccine availability and recommendations, which could have a material adverse effect on our results of operations and financial condition.

Additionally, the pharmaceutical industry has also been the subject of significant publicity in recent years regarding the pricing of pharmaceutical products, including publicity and pressure resulting from prices charged by pharmaceutical companies for new products as well as price increases by pharmaceutical companies on older products that some people have deemed excessive. As a result, pharmaceutical product prices have been the focus of increased scrutiny by the United States government, including certain state attorneys general, members of Congress, the Trump administration, and the United States Department of Justice. If reforms in the healthcare industry limit or reduce reimbursement for our vaccine candidates, the market for such vaccine candidates will be reduced, and we could lose potential sources of revenue. The existence or threat of cost control measures could cause our corporate collaborators to be less willing or able to pursue research and development programs related to our vaccine candidates.

Our vaccine candidates may never achieve market acceptance even if we obtain regulatory approvals.

Even if we receive regulatory approvals for the commercial sale of our vaccine candidates, the commercial success of these vaccine candidates will depend on, among other things, their acceptance by physicians, patients and third-party payers, such as health insurance companies and other members of the medical community, as a vaccine and cost-effective alternative to competing products. If our vaccine candidates fail to gain market acceptance, we may be unable to earn sufficient revenue to continue our business. Market acceptance of, and demand for, any product that we may develop and commercialize will depend on many factors, including:

•our ability to provide acceptable evidence of safety and efficacy;

•the prevalence and severity of adverse side effects;

•whether our vaccines candidates are differentiated from other vaccines;

•availability, relative cost and relative efficacy of alternative and competing treatments;

•the effectiveness of our marketing and distribution strategy;

•publicity concerning our products or competing products and treatments; and

•our ability to obtain sufficient third party insurance coverage or reimbursement.

If our vaccine candidates do not become widely accepted by physicians, patients, third-party payers and other members of the medical community as well as the relevant public health authorities responsible for scheduling immunizations, our business, financial condition and results of operations could be materially and adversely affected.

We may not be able to secure sufficient supplies of a key component of our adjuvant technology.

Because an important component of our adjuvant technology is extracted from a species of soap-bark tree (Quillaja saponaria) grown in Chile, we need long term access to quillaja extract with a consistent and sufficiently high quality in order to maintain a secure supply of raw material for the development and manufacture of our adjuvant products. We rely on a single source supplier for quillaja extract, so if we are unable to secure long term access to quillaja extract with a consistent

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and sufficiently high quality, or to secure back-up suppliers, the development and manufacture of our adjuvant products may be delayed and we may not be able to meet our obligations under our various collaboration and supply agreements.

Our vaccine candidates are sensitive to shipping and storage conditions, which could subject our vaccine candidates to risk of loss or damage.

Our vaccine candidates are sensitive to storage and handling conditions. Loss in vaccine candidates could occur if the product or product intermediates are not stored or handled properly. It is possible that our vaccine candidates could be lost due to expiration prior to use. If we do not effectively maintain our supply logistics, then we may experience an unusual number of returned or out of date products. Failure to effectively maintain our supply logistics, by us or third parties, could lead to additional manufacturing costs and delays in our ability to supply required quantities for clinical trials or otherwise.

Fast Track Designation by the FDA may not actually lead to a faster development or regulatory review or approval process and does not assure approval.

The FDA granted Fast Track Designation for our recombinant quadrivalent seasonal influenza vaccine candidate in January 2020 and prototype vaccine in November 2020, and also granted Fast Track Designation to the R21/Matrix-M malaria vaccine . Depending on the data from our preclinical and clinical studies, we may decide to seek such designation for some or all of our other vaccine candidates. The Fast Track program is intended to expedite or facilitate the process for reviewing candidates that meet certain criteria. Specifically, biologics are eligible for Fast Track designation if they are intended, alone or in combination with one or more drugs or biologics, to treat a serious or life-threatening disease or condition and demonstrate the potential to address unmet medical needs for the disease or condition. With respect to our programs, Fast Track Designation would apply to the combination of the vaccine candidate and the specific indication for which it is being studied. The sponsor of a Fast Track vaccine candidate has opportunities for more frequent interactions with the applicable FDA review team during product development and, once a BLA is submitted, the application may be eligible for priority review. A BLA submitted for a Fast Track candidate may also be eligible for rolling review, where the FDA may consider for review sections of the BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA, the FDA agrees to accept sections of the BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the application.

The FDA has broad discretion whether or not to grant this designation. Even if we believe a particular vaccine candidate is eligible for this designation, we cannot assure you that the FDA would decide to grant it. Even if we do receive Fast Track Designation for any of our vaccine candidates, such vaccine candidates may not experience a faster development process, review or approval compared to conventional FDA procedures. The FDA may also withdraw Fast Track Designation if it believes that the designation is no longer supported by data from our clinical development programs. Furthermore, such a designation does not increase the likelihood that any vaccine candidate that may be granted Fast Track Designation will receive regulatory approval in the U.S. Many candidates that have received Fast Track Designation have ultimately failed to obtain approval.

Risks Related to Our Dependence on Third Parties

We need to partner with a collaborator to handle marketing activities, and if we are unable to enter into collaborations with marketing partners, we may not be successful in commercializing any approved products.

Although we commercialized our COVID-19 Vaccine for the last three vaccination seasons, we have transitioned the commercialization of this product to Sanofi for the 2025-2026 vaccination season and for the duration of the Sanofi CLA and we otherwise currently have limited dedicated sales, marketing or distribution capabilities. As a result, we depend on collaborations with third parties that have established distribution systems and sales forces, including our collaborations with Sanofi and SII, among others. To the extent that we enter into co-promotion or other licensing arrangements, such as the Sanofi CLA, our revenue will depend upon the efforts of third parties, over which we may have little or no control. If we are unable to reach and maintain agreements with one or more pharmaceutical companies or collaborators, we may be required to market our products directly. Developing a marketing and sales force is expensive and time-consuming and could delay a product launch. We may not be able to attract and retain qualified sales personnel or otherwise develop this capability, which may adversely affect our business.

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Current or future regional relationships may hinder our ability to engage in larger transactions.

We have entered into regional collaborations to develop, manufacture and distribute our vaccine candidates in certain parts of the world, and we anticipate entering into additional regional collaborations. Our relationships with SII, Takeda, and SK bioscience are examples of these regional relationships. These relationships often involve the licensing of our technology to our partner or entering into a distribution agreement, frequently on an exclusive basis. Generally, exclusive agreements are restricted to certain territories. Because we have entered into exclusive license and distribution agreements, larger companies may not be interested, or able, to enter into collaborations with us on a worldwide-scale. Also, these regional relationships may make us an unattractive target for an acquisition.

We must identify vaccines for development with our technologies and establish successful third-party relationships.

The near and long-term viability of our other vaccine candidates, including our CIC vaccine candidate, depends in part on our ability to successfully establish, operationalize and maintain strategic collaborations with pharmaceutical and biotechnology companies and government agencies. Establishing, operationalizing and maintaining strategic collaborations and obtaining government funding is difficult and time-consuming. Potential collaborators may reject collaborations based upon their assessment of our financial, regulatory or intellectual property position or based on their internal pipelines; government agencies may reject contract or grant applications based on their assessment of public need, the public interest, our products’ ability to address these areas, or other reasons beyond our expectations or control. Collaborators also may seek to modify or terminate relationships. Past success in establishing strategic collaborations with pharmaceutical and biotechnology companies, non-profit organizations and government agencies is no guarantee of future success in entering into new relationships or in performing under existing relationships. If we fail to establish a sufficient number of collaborations or government relationships on acceptable terms, or fail to perform under collaborations or relationships to the satisfaction of counter-parties, we may not be able to commercialize our vaccine candidates or generate sufficient revenue to fund further research and development efforts.

•The collaborations we have established or may establish may not result in the successful development or commercialization of any vaccine candidates for several reasons, including the fact that:

•we may not have the ability to control the activities of our partners and cannot provide assurance that they will fulfill their obligations to us, including with respect to the license, development and commercialization of any approved vaccines or our vaccine candidates, in a timely manner or at all;

•such partners may not devote sufficient resources to any approved vaccines or our vaccine candidates or properly maintain or defend our intellectual property rights;

•our partners could independently develop, or develop with third parties, products that compete directly or indirectly with any approved vaccines or our vaccine candidates if such partners believe that competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than ours;

•any failure on the part of our partners to perform or satisfy their obligations to us could lead to delays in the development or commercialization of any approved vaccines or our vaccine candidates and affect our ability to realize product revenue; and

•disagreements, including disputes over the ownership of technology developed with such collaborators, could result in litigation, which would be time consuming and expensive, and may delay or terminate research and development efforts, regulatory approvals and commercialization activities.

If we or our collaborators fail to maintain our existing agreements or in the event we fail to establish agreements as necessary, we could be required to undertake research, development, manufacturing and commercialization activities solely at our own expense. These activities would significantly increase our capital requirements and, given our limited sales, marketing and distribution capabilities, significantly delay the commercialization of our vaccine candidates.

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We rely on third parties to conduct preclinical studies and clinical trials. If these third parties do not successfully carry out their contractual duties, comply with applicable regulatory requirements or meet expected deadlines, our development programs and our ability to seek or obtain regulatory approval for or commercialize our vaccine candidates may be delayed.

We depend on third parties to conduct our preclinical studies and clinical trials for our vaccine candidates. Specifically, we rely on, and will continue to rely on, medical institutions, clinical investigators, CROs and consultants to conduct preclinical studies and clinical trials, in each case in accordance with our clinical protocols and regulatory requirements. These CROs, investigators and other third parties play a significant role in the conduct and timing of these trials and subsequent collection and analysis of data. Though we expect to carefully manage our relationships with our CROs, investigators and other third parties, there can be no assurance that we will not encounter challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects. Further, while we will have agreements governing the activities of our third-party contractors, we have limited influence over their actual performance. Nevertheless, we are responsible for ensuring that each of our preclinical studies and clinical trials are conducted in accordance with the applicable protocol and legal, regulatory and scientific standards and requirements, and our reliance on our CROs and other third parties does not relieve us of our regulatory responsibilities. In addition, we and our CROs are required to comply with GCP requirements, which are regulations and guidelines enforced by the FDA and comparable foreign regulatory authorities for our vaccine candidates in clinical development. Regulatory authorities enforce these GCPs through periodic inspections of trial sponsors, principal investigators and trial sites.

If we or any of our CROs or trial sites fail to comply with applicable GCPs, the clinical data generated in our clinical trials may be deemed unreliable, and the FDA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. Furthermore, our clinical trials must be conducted with vaccine candidates and placebo produced under cGMP and similar foreign regulations. Failure to comply with these regulations may require us to repeat clinical trials or recall batches of our vaccine candidate or placebo, which would delay the regulatory approval process.

There is no guarantee that any of our CROs, investigators or other third parties will devote adequate time and resources to our preclinical studies or clinical trials or perform as contractually required. If any of these third parties fails to meet expected deadlines, adhere to our clinical protocols or meet regulatory requirements, or otherwise performs in a substandard manner, our clinical trials may be extended, delayed or terminated. In addition, many of the third parties with whom we contract may also have relationships with other commercial entities, including our competitors, for whom they may also be conducting preclinical studies, clinical trials or other development activities that could harm our competitive position.

If any of our relationships with these third parties terminate, we may not be able to enter into arrangements with alternative third parties on commercially reasonable terms or at all. Switching or adding additional CROs, investigators and other third parties involves additional cost and requires our management’s time and focus. In addition, there is a natural transition period when a new CRO commences work. As a result, delays occur, which can materially impact our ability to meet our desired clinical development timelines. Though we work to carefully manage our relationships with our CROs, investigators and other third parties, there can be no assurance that we will not encounter challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

We currently rely on third parties for the manufacture of our vaccine candidates for clinical development and expect to continue to rely on third parties for the foreseeable future. This reliance on third parties increases the risk that we will not have sufficient quantities of our vaccine candidates or such quantities at an acceptable cost, which could delay, prevent or impair our development or potential commercialization efforts.

We rely, and expect to continue to rely in part, on additional third-party manufacturers for the manufacture of our vaccine candidates and related raw materials for clinical development, as well as for commercial manufacture. The facilities used by third-party manufacturers to manufacture our vaccine candidates must be approved for the manufacture of such candidate by the FDA and any comparable foreign regulatory authority pursuant to inspections that will be conducted after we submit a BLA to the FDA or any comparable submission to a foreign regulatory authority. We do not control the manufacturing process of, and are completely dependent on, third-party manufacturers for compliance with cGMP and similar foreign requirements for manufacture of products. Our third-party manufacturers may be unable to successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or any comparable foreign regulatory authority. In order for us to use the material manufactured by third-party manufacturers, their manufacturing facilities must comply with applicable legal requirements, including cGMP, and upon a request for marketing

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authorization, these facilities must be authorized for the manufacture of our vaccine candidates in connection with any approval of any marketing application we submit.

In addition, we have no control over the ability of third-party manufacturers to procure raw material supplies and maintain adequate quality control, quality assurance and qualified personnel. Furthermore, the process of manufacturing biologics is complex and highly susceptible to product loss due to contamination, equipment failure, improper installation or operation of equipment, vendor or operator error, inconsistency in yields, variability in product characteristics and difficulties in scaling the production process. Even minor deviations from normal manufacturing processes could result in reduced production yields, product defects, other supply disruptions and higher costs. If microbial, viral or other contaminations are discovered at the facilities of our third-party manufacturers, such facilities may need to be closed for an extended period of time to investigate and remedy the contamination, which could delay clinical trials, result in higher costs of drug product and adversely affect our business.

Further, our clinical supplies have a shelf lives that may expire prior to the full enrollment of our planned clinical trials causing similar delays or other supply disruptions. Any performance failure on the part of our third-party manufacturers could delay clinical development or marketing approval of any vaccine candidate, and may adversely affect our future profit margins and our ability to commercialize any vaccines that receive marketing approval on a timely and competitive basis.

In addition, we may be unable to establish any supply agreements with additional third-party manufacturers or to do so on acceptable terms, which increases the risk of failing to timely obtain sufficient quantities of our vaccine candidates or such quantities at an acceptable cost. Even if we are able to establish long-term agreements with third-party manufacturers, reliance on third-party manufacturers entails additional risks, including:

• failure of third-party manufacturers to comply with regulatory requirements and maintain quality assurance; breach of the manufacturing agreement by the third party;

•failure to manufacture our product according to our specifications, our schedule, or at all;

•infringement, misappropriation or other violation of our intellectual property and proprietary information, including our trade secrets and know-how; and

•termination or non renewal of the agreement by the third party at a time that is costly or inconvenient for us.

There are a limited number of manufacturers that operate under cGMP regulations and that might be capable of manufacturing for us, and any vaccine candidates that we may develop may compete with other vaccine candidates and products for access to such manufacturers and manufacturing facilities. Increased competition amongst developers to access manufacturers and materials could increase the costs of, or otherwise limit our ability to, manufacture our vaccine candidates.

If materials manufactured by our third-party manufacturers do not conform to our specifications or the regulatory requirements necessary for use in clinical trials, we may experience delays in our development efforts or may need to find alternative manufacturing facilities, which would significantly impact our ability to obtain regulatory approval for or commercialize our vaccine candidates, if approved.

Our third-party manufacturers may be unable to successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or any comparable foreign regulatory authority. In order for us to use the material manufactured by third-party manufacturers, their manufacturing facilities in which our materials are produced must comply with applicable laws and regulations governing the manufacture of biological products, and upon a request for marketing authorization, these facilities must be authorized for the manufacture of our vaccine candidates in connection with any approval of a marketing application we submit. If the FDA or any comparable foreign regulatory authority determines that such facilities are noncompliant or does not authorize these facilities to manufacture our vaccine candidates or if it withdraws any such authorization in the future, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our vaccine candidates, if

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approved. While we are seeking to identify and secure additional third-party contract manufacturers, we may be unable to do so at an acceptable cost, or at all, which could significantly impact our ability to obtain regulatory approval for or commercialize our vaccine candidates, if approved. Our failure, or the failure of our third-party manufacturers, to comply with applicable regulations could result in sanctions being imposed on us, including clinical holds, fines, injunctions, civil penalties, delays, suspension or withdrawal of approvals, seizures or recalls of vaccine candidates or products, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of our products. Additionally, our third-party manufacturers may rely on single source suppliers for certain of the raw materials for our preclinical and clinical product supplies. If current or future suppliers are delayed or unable to supply sufficient raw materials to manufacture product for our preclinical studies and clinical trials, we may experience delays in our development efforts as materials are obtained or we locate and qualify new raw material manufacturers.

Our or a third party’s failure to execute on our manufacturing requirements on commercially reasonable terms and in compliance with cGMP or other regulatory requirements could adversely affect our business in a number of ways, including:

•an inability to initiate clinical trials of our vaccine candidates;

•delay in submitting regulatory applications, or receiving marketing approvals, for our vaccine candidates;

•subjecting third-party manufacturing facilities or our manufacturing facilities to additional inspections by regulatory authorities;

•requirements to cease development or to recall batches of our vaccine candidates; and

•in the event of approval to market and commercialize our vaccine candidates, an inability to meet commercial demands for such vaccines.

Any performance failure on the part of our manufacturing partners could delay clinical development or marketing approval, and any related remedial measures may be costly or time consuming to implement. In addition, our current and anticipated future dependence upon others for the manufacture of our vaccine candidates may adversely affect our future profit margins and our ability to commercialize any vaccines that receive marketing approval on a timely and competitive basis.

Risks Related to Our Industry and Competition

Many of our competitors have significantly greater resources and experience, which may negatively impact our commercial opportunities and those of our current and future licensees.

The biotechnology and pharmaceutical industries are subject to intense competition and rapid and significant technological change. We have many potential competitors, including major pharmaceutical companies, specialized biotechnology firms, academic institutions, government agencies and private and public research institutions. Many of our competitors have significantly greater financial and technical resources, experience and expertise in:

•research and development;

•preclinical testing;

•designing and implementing clinical trials;

•regulatory processes and approvals;

•production and manufacturing; and

•sales and marketing of approved products.

Principal competitive factors in our industry include:

•the quality and breadth of an organization’s technology;

•management of the organization and the execution of the organization’s strategy;

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•the skill and experience of an organization’s employees and its ability to recruit and retain skilled and experienced employees;

•an organization’s intellectual property portfolio;

•the range of capabilities, from target identification and validation to drug discovery and development to manufacturing and marketing; and

•the availability of substantial capital resources to fund discovery, development and commercialization activities.

Large and established companies, such as Merck & Co., Inc., GlaxoSmithKline plc, CSL Ltd., Sanofi Pasteur, SA, Pfizer Inc., AstraZeneca, and Moderna, among others, compete in the vaccine market. In particular, these companies have greater experience and expertise in securing government contracts and grants to support their research and development efforts, conducting testing and clinical trials, obtaining regulatory approvals to market products, manufacturing such products on a broad scale and marketing approved products.

Smaller or early-stage companies and research institutions also may prove to be significant competitors, regardless of the diseases their product candidates target, particularly through collaborative arrangements with large and established pharmaceutical companies. As these companies develop their technologies, they may develop proprietary positions, which may prevent or limit our product development and commercialization efforts. We will also face competition from these parties in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites and participant registration for clinical trials and in acquiring and in-licensing technologies and products complementary to our programs or potentially advantageous to our business. If any of our competitors succeed in obtaining approval from the FDA or other regulatory authorities for their products sooner than we do or for products that are more effective or less costly than ours, our commercial opportunity could be significantly reduced.

In order to effectively compete, we will have to make substantial investments in development, testing, manufacturing and sales and marketing or partner with one or more established companies. We may not be successful in gaining significant market share for any vaccine. Our technologies and vaccines also may be rendered obsolete or non-competitive as a result of products introduced by our competitors to the marketplace more rapidly and at a lower cost.

There is significant competition in the development of a vaccine against COVID-19 and a combined vaccine against COVID-19 and influenza, and we may never see returns on the significant resources we have devoted and may continue to devote to our vaccine candidates.

Despite funding provided to us to date, and although we obtained regulatory approvals for our COVID-19 Vaccine, many of our competitors pursuing vaccine candidates have significantly greater development, manufacturing and marketing resources than we do. Larger pharmaceutical and biotechnology companies have extensive experience in clinical testing and obtaining regulatory approval for their products and may have the resources to heavily invest to accelerate discovery and development of their vaccine candidates. The success of our candidates will depend, in part, on their relative safety, efficacy (including against emerging variant strains), side effect profile, convenience, and cost. Furthermore, if any competitors are successful in producing a more efficacious vaccine or other treatment for the diseases we intend to target (including against emerging variant strains), or if any competitors are able to manufacture and distribute any such vaccines or treatments with greater efficiency there may be a diversion of potential governmental and other funding away from us and toward such other parties.

Many seasonal influenza vaccines are currently approved and marketed. Competition in the sale of these seasonal influenza vaccines is intense. Therefore, newly developed and approved products must be differentiated from existing vaccines in order to have commercial success. In order to show differentiation in the seasonal influenza market, a product may need to be more efficacious, particularly in older adults, be less expensive or quicker to manufacture, or contain other differentiating characteristics, such as being combined with another vaccine. Many competitors are working on new products and new generations of current products, intended to be more efficacious than those currently marketed. Our CIC vaccine candidate may not prove to be more efficacious than current or future seasonal influenza products or future COVID-19 influenza combination products under development by our competitors. Further, our in-house or third-party manufacturing arrangements may not provide enough savings of time or money to provide the required differentiation for commercial success.

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Risks Related to Regulatory and Compliance Matters

The regulatory approval processes of the FDA and comparable foreign authorities are lengthy, time consuming and inherently unpredictable, and if we are ultimately unable to obtain regulatory approval for our vaccine candidates, our business will be substantially harmed.

The clinical development, manufacturing, labeling, storage, record-keeping, advertising, promotion, import, export, marketing and distribution of our vaccine candidates are subject to extensive regulation by the FDA in the U.S. and by comparable foreign regulatory authorities in foreign markets. In the U.S., we are not permitted to market our vaccine candidates in the U.S. until we receive regulatory approval of a BLA from the FDA. The process of obtaining such regulatory approval is expensive, often takes many years following the commencement of clinical trials and can vary substantially based upon the type, complexity and novelty of the vaccine candidates involved, as well as the target indications and patient population. Approval policies or regulations may change, and the FDA and comparable regulatory have substantial discretion in the approval process, including the ability to delay, limit or deny approval of a vaccine candidate for many reasons. Despite the time and expense invested in clinical development of vaccine candidates, regulatory approval of a vaccine candidate is never guaranteed. Of the large number of drugs in development, only a small percentage successfully complete the FDA or foreign regulatory approval processes and are commercialized.

Prior to obtaining approval to commercialize a vaccine candidate in the U.S. or abroad, we must demonstrate with substantial evidence from adequate and well-controlled clinical trials, and to the satisfaction of the FDA or comparable foreign regulatory authorities, that such vaccine candidates are safe and effective for their intended uses, and in the case of vaccines in the U.S., that such vaccine candidates are safe, pure and potent for their intended uses. Results from nonclinical studies and clinical trials can be interpreted in different ways. Even if we believe available nonclinical or clinical data support the safety purity, potency, or efficacy of our vaccine candidates, such data may not be sufficient to obtain approval from the FDA and comparable foreign regulatory authorities. The FDA or comparable foreign regulatory authorities, as the case may be, may also require us to conduct additional preclinical studies or clinical trials for our vaccine candidates either prior to or post-approval, or may object to elements of our clinical development program.

The FDA or comparable foreign regulatory authorities can delay, limit or deny approval of a vaccine candidate for many reasons, including:

•such authorities may disagree with the design or execution of our clinical trials;

•negative or ambiguous results from our clinical trials or results may not meet the level of statistical significance or persuasiveness required by the FDA or comparable foreign regulatory agencies for approval;

•serious and unexpected drug-related side effects may be experienced by participants in our clinical trials or by individuals using products similar to our vaccine candidates;

•the population studied in the clinical trial may not be sufficiently broad or representative to assure safety in the full population for which we seek approval;

•such authorities may not accept clinical data from trials that are conducted at clinical facilities or in countries where the standard of care is potentially different from that of their own country;

•we may be unable to demonstrate that a vaccine candidate’s clinical and other benefits outweigh its safety risks;

•such authorities may disagree with our interpretation of data from preclinical studies or clinical trials;

•such authorities may not agree that the data collected from clinical trials of our vaccine candidates are acceptable or sufficient to support the submission of a BLA or other submission or to obtain regulatory approval in the U.S. or elsewhere, and such authorities may impose requirements for additional preclinical studies or clinical trials;

•such authorities may disagree with us regarding the formulation, labeling and/or the product specifications of our vaccine candidates;

•approval may be granted only for indications that are significantly more limited than those sought by us, and/or may include significant restrictions on distribution and use;

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•such authorities may find deficiencies in the manufacturing processes or facilities of the third-party manufacturers with which we contract for clinical and commercial supplies; or

•such authorities may not accept a submission due to, among other reasons, the content or formatting of the submission.

With respect to foreign markets, approval procedures vary among countries and, in addition to the foregoing risks, may involve additional product testing, administrative review periods and agreements with pricing authorities. Where if we eventually complete clinical trials and receive approval of a BLA or comparable foreign marketing application for our vaccine candidates, the FDA or comparable foreign regulatory authority may grant approval contingent on the performance of costly additional clinical trials and/or the implementation of a REMS, which may be required because the FDA believes it is necessary to ensure safe use of the product after approval. Any delay in obtaining, or inability to obtain, applicable regulatory approval would delay or prevent commercialization of that vaccine candidate and would materially adversely impact our business and prospects.

Where we receive regulatory approval for our vaccine candidates, we will be subject to ongoing regulatory obligations and continued regulatory review, which may result in significant additional expense. Additionally, our vaccine candidates, if approved, could be subject to labeling and other restrictions on marketing or withdrawal from the market, and we may be subject to penalties if we fail to comply with regulatory requirements or if we experience unanticipated problems with our vaccine candidates, when and if any of them are approved.

Any regulatory approvals that we may receive for our vaccine candidates will require the submission of reports to regulatory authorities, subject us to surveillance to monitor the safety and efficacy of the product, may contain significant limitations related to use restrictions for specified age groups, warnings, precautions or contraindications, and may include burdensome post-approval study or risk management requirements. For example, the FDA may require a REMS as a condition of approval of our vaccine candidates, which could include requirements for a medication guide, physician communication plans or additional elements to ensure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. In addition, if the FDA or a comparable foreign regulatory authority approves our vaccine candidates, the manufacturing processes, labeling, packaging, distribution, adverse event reporting, storage, advertising, promotion, import, export and recordkeeping for our products will be subject to extensive and ongoing regulatory requirements. These requirements include submissions of safety and other post-marketing information and reports, registration, as well as continued compliance with cGMPs and similar foreign requirements, and GCP requirements for any clinical trials that we conduct post-approval. Failure to comply with regulatory requirements or later discovery of previously unknown problems with our products, including adverse events of unanticipated severity or frequency, or with our third-party manufacturers or manufacturing processes, may result in, among other things:

•restrictions on the marketing or manufacturing of our products, withdrawal of the product from the market or voluntary or mandatory product recalls;

•restrictions on product distribution or use, or requirements to conduct post-marketing studies or clinical trials;

•restrictions on our ability to conduct clinical trials, including full or partial clinical holds on clinical trials;

•fines, restitutions, disgorgement of profits or revenue, warning letters, untitled letters, adverse publicity requirements or holds on clinical trials;

•refusal by the FDA or other regulatory authorities to approve pending applications or supplements to approved applications submitted by us or suspension or revocation of approvals;

•product seizure or detention, or refusal to permit the import or export of our products; and

•injunctions or the imposition of civil or criminal penalties.

The occurrence of any event or penalty described above may inhibit our ability to commercialize our vaccine candidates and generate revenue and could require us to expend significant time and resources in response and could generate negative publicity.

Moreover, the FDA’s and other regulatory authorities’ policies may change and additional government regulations may be promulgated that could prevent, limit or delay marketing authorization of any vaccine candidates we develop. For example, the Trump administration may issue executive orders or take other actions that could impose significant burdens on,

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or otherwise materially delay, the FDA’s ability to engage in routine oversight activities such as implementing statutes through rulemaking, issuance of guidance, and review and approval of marketing applications. The policies and priorities of a presidential administration could materially impact the regulations governing our vaccine candidates. In particular, the current DHHS Secretary, Robert F. Kennedy, Jr., has previously issued statements expressing skepticism towards the safety and testing of pediatric vaccines, such as those we intend to develop, and has taken actions to modify certain committees and recommendations that could adversely affect the development, approval and/or commercialization of novel vaccines. For additional information, see the Risk Factor above entitled: “Even if we successfully commercialize any of our vaccine candidates, either alone or in collaboration, we face uncertainty with respect to pricing, third-party reimbursement and healthcare reform, all of which could be subject to change, and could adversely affect any commercial success of our vaccine candidates.”

If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may be subject to enforcement action and we may not achieve or sustain profitability.

Our vaccine candidates for which we intend to seek approval as biologic products may face competition sooner than anticipated.

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, includes a subtitle called the Biologics Price Competition and Innovation Act of 2009 (“BPCIA”), which created an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-licensed reference biological product. Under the BPCIA, an application for a highly similar or “biosimilar” product may not be submitted to the FDA until four years following the date that the reference product was first approved by the FDA. In addition, the approval of a biosimilar product may not be made effective by the FDA until 12 years from the date on which the reference product was first approved. During this 12-year period of exclusivity, the FDA may approve a full BLA for the competing product containing the sponsor’s own preclinical data and data from adequate and well-controlled clinical trials to demonstrate the safety, purity and potency of their product. We believe that any of our vaccine candidates approved as a biological product under a BLA should qualify for the 12-year period of exclusivity. However, there is a risk that this exclusivity could be shortened due to congressional action or otherwise, or that the FDA will not consider our vaccine candidates to be reference products for competing products, potentially creating the opportunity for competition sooner than anticipated.

Failure to obtain regulatory approval in foreign jurisdictions could prevent us from marketing our products internationally.

We intend to have our vaccine candidates developed and commercialized outside the U.S. In furtherance of this objective, we have entered into supply agreements with various foreign governments and international distribution agreements with commercial entities. In order to market our products in various countries globally, we must obtain separate regulatory approvals and comply with numerous and varying regulatory requirements. The approval procedure varies among countries and can involve additional testing and data review. The time required to obtain foreign regulatory approval may differ from that required to obtain FDA approval. The foreign regulatory approval process may include all of the risks associated with obtaining FDA approval. Additionally, regulatory authorities outside the U.S. might not accept data from trials conducted in other countries. Approval by one regulatory agency does not ensure approval by regulatory agencies in other jurisdictions. However, a failure or delay in obtaining regulatory approval in one jurisdiction may have a negative effect on the regulatory approval process in other jurisdictions, including approval by the FDA. The failure to obtain regulatory approval in foreign jurisdictions could harm our business.

We have conducted, continue to conduct and plan to conduct in the future, a number of clinical trials for our vaccine candidates at sites outside the U.S. and the U.S. FDA may not accept data from trials conducted in such locations.

We have in the past conducted, and may in the future conduct one or more of our clinical trials or a portion of our clinical trials for our vaccine candidates outside the U.S. The acceptance of study data from clinical trials conducted outside the U.S. or another jurisdiction by the FDA or comparable foreign regulatory authority may be subject to certain conditions or may not be accepted at all. In cases where data from foreign clinical trials are intended to serve as the sole basis for regulatory approval in the U.S., the FDA will generally not approve the application on the basis of foreign data alone unless (i) the data are applicable to the U.S. population and U.S. medical practice; (ii) the trials were performed by clinical investigators of recognized competence and pursuant to GCP regulations; and (iii) the data may be considered valid without the need for an on-site inspection by the FDA, or if the FDA considers such inspection to be necessary, the FDA is able to validate the data through an on-site inspection or other appropriate means. In addition, even where the foreign study data are

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not intended to serve as the sole basis for approval, if the study was not otherwise subject to an IND, the FDA will not accept the data as support for an application for regulatory approval unless the study is well-designed and well-conducted in accordance with GCP requirements and the FDA is able to validate the data from the study through an onsite inspection if deemed necessary. Many foreign regulatory authorities have similar requirements for clinical data gathered outside of their respective jurisdictions. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA or any comparable foreign regulatory authority will accept data from trials conducted outside of the U.S. or the relevant jurisdiction. If the FDA or any comparable foreign regulatory authority does not accept such data, it may result in the need for additional trials, which could be costly and time-consuming, and which may result in current or future vaccine candidates that we may develop not receiving approval for commercialization in the applicable jurisdiction.

Inadequate funding for the FDA, the SEC and other regulatory authorities could hinder their ability to hire and retain key leadership and other personnel, or otherwise perform their normal functions on which the operation of our business may rely, which could negatively impact our ability to develop or commercialize new products or services, access capital markets, or otherwise operate our business.

The ability of the FDA and other regulatory authorities to review and approve new product applications is affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory and policy changes, including those related to a change in presidential administration. For example, average review times at the FDA have fluctuated in recent years as a result of such factors. In addition, government funding of the SEC and other government agencies on which our operations may rely, including those that fund research and development activities, is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs to be reviewed and approved by necessary government agencies, which would adversely affect our business. For example, in recent years, the U.S. government has shut down several times and certain regulatory agencies, such as the FDA and the SEC, have had to furlough employees and stop or slow the pace of critical activities. In addition, the current U.S. Presidential administration has issued certain policies and Executive Orders directed towards reducing the employee headcount and costs associated with U.S. administrative agencies, including the FDA, which have led to substantial personnel changes, and it remains unclear the degree to which these efforts may limit or otherwise adversely affect the FDA’s ability to conduct routine activities. If a prolonged government shutdown or slowdown of the relevant regulatory authority occurs, or if funding shortages, staffing limitations or similar factors hinder or prevent the FDA or other regulatory authorities from conducting their regular inspections, reviews, or other regulatory activities, such events, could significantly impact the ability of such government or authority to timely review and process our regulatory submissions, which could have a material adverse effect on our business. Further, in our operations as a public company, future government shutdowns could impact our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

Because we are subject to environmental, health and safety laws, we may be unable to conduct our business in the most advantageous manner.

We are subject to various laws and regulations relating to safe working conditions, laboratory and manufacturing practices, the experimental use of animals, emissions and wastewater discharges, and the use and disposal of hazardous or potentially hazardous substances used in connection with our research, including infectious disease agents. We also cannot accurately predict the extent of regulations that might result from any future legislative or administrative action. Any of these laws or regulations could cause us to incur additional expense or restrict our operations.

Our facilities in Maryland are subject to various local, state and federal laws and regulations relating to safe working conditions, laboratory practices, the experimental use of animals and the use and disposal of hazardous or potentially hazardous substances, including chemicals, microorganisms and various hazardous compounds used in connection with our research and development activities. In the U.S., these laws include the Occupational Safety and Health Act, the Toxic Test Substances Control Act and the Resource Conservation and Recovery Act. Similar national and local regulations govern our facilities in Sweden and Switzerland. We cannot eliminate the risk of accidental contamination or discharge or injury from these materials. Federal, state and local laws and regulations govern the use, manufacture, storage, handling and disposal of these materials. We could be subject to civil damages in the event of an improper or unauthorized release of, or exposure of individuals to, these hazardous materials. In addition, claimants may sue us for injury or contamination that results from our use or the use by third parties of these materials, and our liability may exceed our total assets. Compliance with environmental laws and regulations may be expensive, and current or future environmental regulations may impair our research, development or production efforts.

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Although we have general liability insurance, these policies contain exclusions from insurance against claims arising from pollution from chemicals or pollution from conditions arising from our operations. Our collaborators are working with these types of hazardous materials in connection with our collaborations. In the event of a lawsuit or investigation, we could be held responsible for any injury we or our collaborators cause to persons or property by exposure to, or release of, any hazardous materials.

For our vaccine candidates, we will be subject to additional healthcare laws and our failure to comply with those laws could have a material adverse effect on our results of operations and financial conditions.

Within the U.S. (and within foreign countries), if we obtain full approval for any of our vaccine candidates and begin commercializing them, our operations may be directly, or indirectly through our arrangements with third-party payors and customers, subject to additional healthcare regulation and enforcement by the federal and state governments (or the regulatory bodies or governments of foreign countries), which may constrain the business or financial arrangements and relationships through which we sell, market and distribute our products. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, structuring and commission(s), certain customer incentive programs and other business arrangements generally. Activities subject to these laws also involve the improper use of information obtained in the course of patient recruitment for clinical trials. The applicable U.S. federal and state healthcare laws and regulations (which may be comparable to foreign laws existing in foreign countries) that may affect our ability to operate include:

•the Federal Food, Drug and Cosmetic Act, which among other things, strictly regulates drug product marketing and promotion and prohibits manufacturers from marketing such products for unapproved uses;

•the federal Anti-Kickback Statute, which prohibits, among other things, persons from knowingly and willfully soliciting, receiving or providing remuneration, directly or indirectly, to induce the referral for an item or service or the purchase order of a good or service, for which payment may be made under federal healthcare programs such as Medicare and Medicaid. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it to have committed a violation;

•federal false claims laws, including the FCA, which prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, information or claims for payment from Medicare, Medicaid, or other third-party payers that are false or fraudulent, knowingly making, using or causing to be made or used, a false record or statement material to a false or fraudulent claim or from knowingly making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government. In addition, the government may assert that a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the FCA;

•manufacturers can be held liable under the FCA even when they do not submit claims directly to government payors if they are deemed to “cause” the submission of false or fraudulent claims; the FCA also permits a private individual acting as whistleblower to bring actions on behalf of the federal government alleging violations of the FCA and to share in any monetary recovery;

•federal laws that require pharmaceutical manufacturers to report certain calculated product prices to the government or provide certain discounts or rebates to government authorities or private entities, often as a condition of reimbursement under government healthcare programs;

•the federal Physician Payment Sunshine Act and its implementing regulations, which require manufacturers of drugs, devices, biologicals, and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program (with certain exceptions) to report annually to the DHHS information related to payments or other transfers of value made to physicians (defined to include doctors, dentists, optometrists and chiropractors), certain non-physician providers such as physician assistants and nurse practitioners, and teaching hospitals, as well as ownership and investment interests held by physicians and their immediate family members;

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•the federal law known as HIPAA, which, in addition to privacy protections applicable to healthcare providers and other entities, prohibits executing a scheme to defraud any healthcare benefit program or making false statements relating to healthcare matters. Similar to the federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it to have committed a violation;

•federal consumer protection and unfair competition laws, which broadly regulate marketplace activities and activities that potentially harm consumers;

•state law equivalents of the above federal laws, such as anti-kickback and false claims laws which may apply to items or services reimbursed by any third-party payer, including commercial insurers, and state gift ban and transparency laws, many of which state laws differ from each other in significant ways and often are not preempted by federal laws, thus complicating compliance efforts; and

•state laws restricting interactions with healthcare providers and other members of the healthcare community or requiring pharmaceutical manufacturers to implement certain compliance standards.

Because of the breadth of these laws and the narrowness of the statutory exceptions and safe harbors available, it is possible that some of our business activities could be subject to challenge under one or more of such laws. It is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent inappropriate conduct may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations. Efforts to ensure that our business arrangements will comply with applicable healthcare laws may involve substantial costs. It is possible that governmental and enforcement authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law interpreting applicable fraud and abuse or other healthcare laws and regulations. If any such actions are instituted against us and we are not successful in defending ourselves or asserting our rights those actions, our business may be impaired.

If our operations are found to be in violation of any of such laws or any other governmental regulations that apply to us, we may be subject to, on a corporate or individual basis, penalties, including civil and criminal penalties, damages, fines, the curtailment or restructuring of our operations, the exclusion from participation in federal and state healthcare programs and even imprisonment, any of which could materially adversely affect our ability to operate our business and our financial results. In addition, the cost of implementing sufficient systems, controls, and processes to ensure compliance with all of the aforementioned laws could be significant. Any action for violation of these laws, even if successfully defended, could cause us to incur significant legal expenses and divert management’s attention from the operation of the company’s business. If any of the physicians or other healthcare providers or entities with whom we expect to do business is found not to be in compliance with applicable laws, that person or entity may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs. Prohibitions or restrictions on sales or withdrawal of future marketed products could materially affect business in an adverse way.

We are also subject to anti-bribery and anti-corruption laws, including the FCPA, the UK Bribery Act, and other similar worldwide anti-bribery laws, as well as various trade laws and regulations (including economic sanctions, export laws, and customs laws), and our failure to comply with those laws could have a material adverse effect on our results of operations and financial conditions.

The FCPA and similar worldwide anti-bribery and anti-corruption laws prohibit companies and their intermediaries from corruptly providing any payments or other benefits to foreign government officials for the purpose of obtaining or retaining business. The U.S. Departments of Justice, Securities & Exchange Commission, Commerce, State and Treasury and other federal agencies and authorities have a broad range of civil and criminal penalties they may seek to impose against corporations and individuals for violations of the FCPA, economic sanctions laws, export control laws, and other federal statutes and regulations, including those established by the Office of Foreign Assets Control, or OFAC. In addition, the UK Bribery Act of 2010, or the Bribery Act, prohibits both domestic and international bribery, as well as bribery across both private and public sectors. An organization that fails to prevent bribery by anyone associated with the organization can be charged under the Bribery Act unless the organization can establish the defense of having implemented adequate procedures to prevent bribery.

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Similarly, U.S. and similar worldwide trade laws, including economic sanctions, export laws, and customs laws, regulate our ability to conduct business with certain jurisdictions and counterparties, and regulate the ways in which we may export and import products around the world. In connection with these laws, various government agencies may require us to obtain export licenses, and may impose modifications to business practices, including requiring the cessation of business activities in or with countries, entities, and individuals targeted with sanctions. The breadth and dynamic nature of these laws and regulations may increase compliance costs, and may subject us to fines.

We have received a number of regulatory approvals in ex-U.S. jurisdictions and has commenced commercial operations in these international locations, including partnering with third-parties in certain higher-risk jurisdictions. Further, a portion of our business with respect to our manufacturing is conducted outside of the U.S. in higher-risk jurisdictions. We expect our international activities to increase in the future. Though we maintain policies, internal controls and other measures reasonably designed to promote compliance with applicable anti-corruption and trade laws and regulations, our employees or agents may nevertheless engage in improper conduct for which we might be held responsible. Any violations of these anti-corruption or trade laws, or even allegations of such violations, can lead to an investigation and/or enforcement action, which could disrupt our operations, involve significant management distraction, and lead to significant costs and expenses, including legal fees. If we, or our employees or agents acting on our behalf, are found to have engaged in practices that violate these laws and regulations, we could be subject to criminal and civil enforcement action, suffer severe fines and penalties, profit disgorgement, injunctions on future conduct, securities litigation, bans on transacting government business, delisting from securities exchanges and other consequences that may have a material adverse effect on our business, financial condition and results of operations. In addition, our reputation, our revenue or our stock price could be adversely affected if we become the subject of any negative publicity related to actual or potential violations of anti-corruption or trade laws and regulations.

Risks Related to our Intellectual Property

Our success depends on our ability to obtain, maintain, expand, enforce and defend the scope, ownership or control, and validity of intellectual property protections, to maintain the proprietary nature of our technology.

We rely, and may in the future rely, upon a combination of patent, trade secret and know-how for any of our current and future vaccine candidates, and proprietary technologies to prevent third parties from exploiting our achievements, thus eroding our competitive position in our market. These legal measures afford only limited protection, and competitors or others may gain access to or use our intellectual property and proprietary information. Our success in large part depends on our ability to obtain, maintain, expand, enforce and defend the scope, ownership or control, and validity of intellectual property, to maintain the proprietary nature of our technology and other trade secrets in the United States and other countries. To do so, we must prosecute and maintain existing patents, obtain new patents and pursue trade secret and other intellectual property protection. We also must operate without infringing the proprietary rights of third-parties or allowing third-parties to infringe our rights. We currently have or have rights to over 832 U.S. and foreign patents and patent applications covering our technologies. However, patent issues relating to pharmaceuticals and biologics involve complex legal, scientific and factual questions. To date, no consistent policy has emerged regarding the breadth of biotechnology patent claims that are granted by the U.S. Patent and Trademark Office (“USPTO”) or similar patent offices in other countries or enforced by the federal courts or agencies in the United States or the courts or administrative bodies in other countries. Therefore, we do not know whether any particular patent applications will result in the issuance of patents, or that any patents issued to us will provide us with any competitive advantage. We also cannot be sure that we will develop additional proprietary products that are patentable. Furthermore, there is a risk that others will independently develop or duplicate similar technology or products or circumvent the patents issued to us.

The USPTO and various non-U.S. government agencies require compliance with several procedural, documentary, fee payment and other similar provisions during the patent application process. In addition, the USPTO and various non-U.S. government agencies require compliance with certain foreign filing requirements during the patent application process. In some circumstances, we are dependent on our licensors to take the necessary action to comply with these requirements with respect to our licensed intellectual property. In some cases, an inadvertent lapse in compliance with these requirements can be cured by payment of a late fee or by other means in accordance with the applicable rules. There are situations, however, in which non-compliance can result in abandonment or lapse of the patent or patent application or can be grounds for revoking or invalidating an issued patent, resulting in a partial or complete loss of patent rights in the relevant jurisdiction. In such an event, potential competitors might be able to enter the market with similar or identical products or technology, which could have a material adverse effect on our business, financial condition, results of operations and prospects.

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In addition, we may experience difficulties in enforcing the intellectual property rights in output generated by generative AI Technologies (as defined below). The United States Copyright Office has previously denied copyright protection for content generated by AI Technologies, and the United States Patent and Trademark Office has similarly stated that an AI tool cannot be an “inventor” of a patent, rendering it impossible to obtain patent protection for inventions created solely by AI Technologies. The Supreme Court of the United Kingdom has reached a similar conclusion, stating that AI systems cannot be named as an “inventor” for UK patent law purposes.

If we are unable to obtain, maintain, expand, enforce and defend the scope, ownership or control, validity and enforceability of our intellectual property protection, our business, financial condition, results of operations and prospects could be materially harmed.

If we are unable to protect the confidentiality of our trade secrets, our business and competitive position would be harmed.

In addition to seeking patent protection for our products, vaccine candidates and proprietary technologies, we may rely on trade secret protection and confidentiality agreements to protect our know-how, technology, and other proprietary information and to maintain our competitive position. We seek to protect these trade secrets and other proprietary technology, in part, by entering into non-disclosure and confidentiality provisions in agreements with parties who have access to them, such as our employees, licensees, third party collaborators, CROs, contract manufacturers, consultants, advisors and other third parties. We also enter into confidentiality and invention or patent assignment agreements with our employees, consultants and advisors. Trade secrets and know-how can be difficult to protect. We cannot guarantee that we have entered into applicable agreements with each party that may have or have had access to our trade secrets or proprietary technology and processes. Despite these efforts, any of these parties may breach the agreements and disclose our proprietary information, including our trade secrets, and we may not be able to obtain adequate remedies for such breaches. Monitoring unauthorized uses and disclosures is difficult, and we do not know whether the steps we have taken to protect our proprietary technologies will be effective. We cannot guarantee that any potential trade secrets and other proprietary and confidential information will not be disclosed or that competitors will not otherwise gain access to trade secrets. Enforcing a claim that a party illegally disclosed or misappropriated a trade secret is difficult, expensive and time-consuming, and the outcome is unpredictable. In addition, some courts inside and outside the U.S. are less willing or unwilling to protect trade secrets. If any of our trade secrets were to be lawfully obtained or independently developed by a competitor or other third party, we may have no right to prevent them from using that technology or information to compete with us. Furthermore, others may independently discover similar trade secrets and proprietary information. We may also need to share our trade secrets and proprietary know-how with current or future partners, collaborators, contractors and others located in countries at heightened risk of theft of trade secrets, including through direct intrusion by private parties or foreign actors, and those affiliated with or controlled by state actors. As a result, we may encounter significant problems in protecting and defending our intellectual property both in the U.S. and abroad. If any of our trade secrets were to be disclosed or misappropriated or if any such information were to be independently developed by a competitor or other third party, our competitive position could be materially and adversely harmed.

We may be subject to claims that third parties have an ownership interest in our trade secrets. For example, we may have disputes arise from conflicting obligations of our employees, consultants, advisors or others who are involved in our research and development activities or developing our vaccine candidates. Litigation may be necessary to defend against these and other claims challenging ownership of our trade secrets. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable trade secret rights, such as exclusive ownership of, or right to use, trade secrets that are important to our vaccine candidates and other proprietary technologies we may develop. 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 our management and other employees. Any of the foregoing could have a material adverse effect on our business, financial condition, results of operations and prospects.

Our former employees, consultants, advisors and collaborators may wrongfully disclose our trade secrets or we may be subject to claims that our employees, consultants, or advisors have misappropriated alleged trade secrets of their current or former employers or claims asserting ownership of what we regard as our own intellectual property.

Although our patent filings include claims covering various features of our vaccine candidates, including composition, methods of manufacture and use, our patents do not provide us with complete protection against the development of competing products. Some of our know-how and technology is not patentable. To protect our proprietary rights in unpatentable intellectual property and trade secrets, we require employees, consultants, advisors and collaborators to enter into confidentiality agreements. These agreements may not provide meaningful protection for our trade secrets, know-

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how or other proprietary information, and such risk has been enhanced by the departure of employees in connection with our global restructuring and cost reduction plan.

Some of our employees, consultants and advisors are currently or 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 advisors 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 these individuals have used or disclosed intellectual property, including trade secrets or other proprietary information, of any such individual’s current or former employer. 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. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to our management.

In addition, while it is our policy to require our employees and contractors who may be involved in the conception or development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who, in fact, conceives or develops intellectual property that we regard as our own. The assignment of intellectual property rights may not be self-executing, or the assignment agreements may be breached, and we may be forced to bring claims against third parties, or defend claims that they may bring against us, to determine the ownership of what we regard as our intellectual property. Such claims could have a material adverse effect on our business, financial condition, results of operations and prospects.

We may not be able to protect our intellectual property and proprietary rights throughout the world.

Filing, prosecuting, maintaining, enforcing and defending patents on our products and vaccine candidates in all countries throughout the world is expensive, and the laws of foreign countries may not protect our intellectual property rights to the same extent as the laws of the U.S. Prosecution of foreign patent applications is often a longer process and patents may grant at a later date, and may have a shorter term, than in the U.S. The requirements for patentability differ in certain jurisdictions and countries. Additionally, the patent laws of some countries do not afford intellectual property protection to the same extent as the laws of the U.S. For example, other countries may impose substantial restrictions on the scope of claims, including limiting patent protection to specifically disclosed embodiments. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the U.S., or from selling or importing products made using our intellectual property in and into the U.S. or other jurisdictions. Competitors may use our intellectual property in jurisdictions where we have not pursued and 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 U.S. These products may compete with our products, and our current or future owned or licensed 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 biopharmaceutical products, which could make it difficult for us to stop the infringement of our owned or licensed patents or marketing of competing products in violation of our intellectual property and proprietary rights generally. In addition, some jurisdictions may have a heightened standard for patentability than in the U.S., including, for example, the requirement of claims having literal support in the original patent filing and the limitation on using supporting data that is not in the original patent filing. Under those heightened patentability requirements, we may not be able to obtain sufficient patent protection in certain jurisdictions even though the same or similar patent protection can be secured in the U.S. and other jurisdictions.

Failure to obtain trademark registrations for proposed product names/brands, in the U.S. or abroad, may adversely impact our business.

Trademark registration to protect the trademarks for our proposed products will require approval from the USPTO in the U.S. and in trademark offices throughout the world in our key markets. The USPTO or a trademark office in a key international jurisdiction may refuse registration of any of our trademarks on a variety of potential grounds. If registration is not granted to one of our trademarks in the U.S. or in another key international jurisdiction, we may be required to adopt an alternative name for that proposed product. If we adopt an alternative name, we may lose the benefit of any existing trademark applications for such developmental candidate and may be required to expend significant additional resources in an effort to identify a suitable product name that would qualify under applicable trademark laws, not infringe the existing rights of third parties and be acceptable to the FDA and other regulatory authorities.

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Third parties may claim we infringe their intellectual property rights.

Our research, development and commercialization activities, including any vaccine candidates resulting from these activities, may be found to infringe patents or trademarks owned by third-parties and to which we do not hold licenses or other rights. There may be rights we are not aware of, including applications that have been filed, but not published that, when issued, could be asserted against us. These third-parties could bring claims against us, and that may cause us to incur substantial expenses and, if successful against us, could cause us to pay substantial damages. Further, if a patent or trademark infringement suit were brought against us, we could be forced to stop or delay research, development, manufacturing or sales of the product or biologic drug candidate that is the subject of the suit.

As a result of patent or trademark infringement claims, or in order to avoid potential claims, we may choose or be required to seek a license from the third party. These licenses may not be available on acceptable terms, or at all. Even if we are able to obtain a license, the license would likely obligate us to pay license fees or royalties or both, and the rights granted to us might be non- exclusive, which could result in our competitors gaining access to the same intellectual property. Ultimately, we could be prevented from commercializing a product, or be forced to cease some aspect of our business operations, if, as a result of actual or threatened patent or trademark infringement claims, we are unable to enter into licenses on acceptable terms. All of the issues described above could also impact our collaborators, which would also impact the success of the collaboration and therefore us.

There has been substantial litigation and other proceedings regarding patent, trademark, and other intellectual property rights in the pharmaceutical and biotechnology industries.

We may become involved in litigation to defend or enforce our intellectual property or the intellectual property of our collaborators or licensors, which could be expensive and time-consuming.

Competitors may infringe our patents or the patents of our collaborators or licensors. As a result, we may be required to file patent infringement suits to prevent unauthorized uses. This can be expensive and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours is not valid or is unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that our patents do not cover its technology. An adverse determination of any litigation or defense proceeding could put one or more of our, or our collaborators’ or licensors’, patents at risk of being invalidated or interpreted narrowly and could put our, or our collaborators’ or licensors’, patent applications at the risk of not issuing. Competitors may infringe our trademarks or the trademarks of collaborators or licensors. As a result, we may be required to file suit to counter infringement for unauthorized use of an identical or confusingly similar trademark. This can be expensive and time-consuming.

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