tv490876-424b5alt - none - 2.2500864s
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 Filed Pursuant to Rule 424(b)(5)
 Registration No. 333-222365​
The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement is not an offer to sell these securities and is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.
Subject to Completion Dated April 11, 2018
P R E L I M I N A R Y   P R O S P E C T U S   S U P P L E M E N T
(to Prospectus dated January 12, 2018)
           Shares
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Novavax, Inc.
Common Stock
We are offering up to            shares of our common stock.
Our common stock is listed on The Nasdaq Global Select Market under the symbol “NVAX”. The last reported sale price of our common stock on April 6, 2018, as reported by The Nasdaq Global Select Market, was $2.02 per share.
You should read this prospectus supplement and the accompanying prospectus, including any information incorporated herein by reference, carefully before you invest.
Investing in our common stock involves a high degree of risk. See “RISK FACTORS” on page S-4 of this prospectus supplement and page 3 of the accompanying prospectus.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.
Per Share
Total
Public offering price $                 $                
Underwriting discount $ $
Proceeds, before expenses, to us $ $
The underwriters also may purchase up to an additional           shares of our common stock at the public offering price, less the underwriting discounts and commissions payable by us, within 30 days from the date of this prospectus supplement. If the underwriters exercise this option in full, the total underwriting discounts and commissions will be $        and our total proceeds, after underwriting discounts and commissions but before expenses, will be $           .
The underwriters are offering the common stock as set forth under “Underwriting.” Delivery of the shares will be made on or about            , 2018.
Joint Book-Running Managers
Citigroup
Piper Jaffray​
The date of this Prospectus Supplement is            , 2018

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Prospectus Supplement
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ABOUT THIS PROSPECTUS SUPPLEMENT
This document consists of two parts. The first part is this prospectus supplement, which describes the specific terms of this offering. The second part, the accompanying prospectus, gives more general information, some of which may not apply to this offering. Generally, when we refer only to the “prospectus,” we are referring to both parts combined. This prospectus supplement may add to, update or change information in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement or the accompanying prospectus.
If information in this prospectus supplement is inconsistent with the accompanying prospectus, you should rely on this prospectus supplement. This prospectus supplement, the accompanying prospectus and the documents incorporated into each by reference include important information about us, the shares of common stock being offered and other information you should know before investing in these securities.
You should rely only on this prospectus supplement, the accompanying prospectus and the information incorporated or deemed to be incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectuses we have prepared. We have not, and the underwriters have not, authorized anyone to provide you with information that is in addition to, or different from, that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or in any free writing prospectuses we have prepared. If anyone provides you with different or inconsistent information, you should not rely on it. We are not, and the underwriters are not, offering to sell these securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained or incorporated by reference in this prospectus supplement or the accompanying prospectus is accurate as of any date other than as of the date of this prospectus supplement or the accompanying prospectus, as the case may be, or in the case of the documents incorporated by reference, the date of such documents, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or any sale of shares of our common stock. Our business, financial condition, liquidity, results of operations, and prospects may have changed since those dates.
Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus supplement to “the Company,” “Novavax,” “we,” “us” and “our” refer to Novavax, Inc.
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PROSPECTUS SUMMARY
The following is a summary of selected information about us contained elsewhere or incorporated by reference in this prospectus supplement and the accompanying prospectus. It does not contain all of the information that you should consider before buying our securities. You should read this entire prospectus supplement and accompanying prospectus carefully, as well as the documents incorporated by reference and any free writing prospectus we provide to you, including the information referred to under the heading “Risk Factors.”
NOVAVAX
Novavax is a clinical-stage biotechnology company focused on the discovery, development and commercialization of recombinant nanoparticle vaccines and adjuvants. Using innovative proprietary recombinant nanoparticle vaccine platform technology, we produce vaccine candidates to efficiently and effectively respond to both known and emerging disease threats. Our vaccine candidates are genetically engineered three-dimensional nanostructures that incorporate recombinant proteins critical to disease pathogenesis. Our product pipeline targets a variety of infectious diseases, with clinical vaccine candidates for respiratory syncytial virus (RSV), influenza and Ebola virus (EBOV), and preclinical programs for other infectious disease vaccine candidates.
We are also developing immune stimulating saponin-based adjuvants through our wholly owned Swedish subsidiary, Novavax AB. Our lead adjuvant, Matrix-M™, has been shown to enhance immune responses and was well-tolerated in multiple clinical trials that we have conducted.
Novavax was incorporated in 1987 under the laws of the State of Delaware. Our principal executive offices are located at 20 Firstfield Road, Gaithersburg, Maryland, 20878. Our telephone number is (240) 268-2000 and our website address is www.novavax.com. The information contained in, and that can be accessed through, our website is not incorporated into and does not form a part of this prospectus supplement or the accompanying prospectus.
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THE OFFERING
The following summary contains basic information about our common stock and the offering and is not intended to be complete. It does not contain all the information that may be important to you. For a more complete understanding of our common stock, you should read the section in the accompanying prospectus entitled “Description of Our Capital Stock” and the documents referred to therein.
Issuer
Novavax, Inc.
Common stock offered by us
          shares.
Option to purchase additional shares 
We have granted the underwriters an option for a period of 30 days from the date of this prospectus supplement to purchase up to           additional shares of our common stock.
Common stock to be outstanding after this offering
          shares (or           shares, if the underwriters exercise in full their/its option to purchase additional shares).
Use of proceeds
We intend to use the net proceeds from this offering for general corporate purposes, including but not limited to working capital, capital expenditures, research and development expenditures, clinical trial expenditures, as well as acquisitions and other strategic purposes. See the section titled “Use of Proceeds.”
Risk factors
Your investment in our common shares involves substantial risks. You should consider the matters referred to under the heading “Risk Factors” on page S-4 of this prospectus supplement, page 3 of the accompanying prospectus and the risk factors incorporated by reference from our filings with the Securities and Exchange Commission (the “SEC,” or the “Commission”).
Nasdaq ticker symbol
NVAX
The number of shares of our common stock to be outstanding after this offering is based on 346,748,986 shares of our common stock outstanding as of March 31, 2018.
The number of shares of our common stock to be outstanding after this offering excludes the following, each as of March 31, 2018:

45,126,499 shares of our common stock reserved for issuance upon the exercise of outstanding stock options at a weighted average exercise price of  $3.50 per share;

270,880 shares of our common stock reserved for issuance under our Employee Stock Purchase Plan; and

2,883,708 shares of our common stock reserved for issuance under our 2015 Stock Incentive Plan, as amended.
Unless otherwise stated, all information in this prospectus supplement assumes no exercise by the underwriters of their option to purchase additional shares.
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NOTE REGARDING FORWARD-LOOKING STATEMENTS
This prospectus supplement, the accompanying prospectus and the other documents we have filed with the SEC that are incorporated herein by reference include forward-looking statements. Such forward-looking statements involve risks and uncertainties, as well as assumptions that, if they never materialize or prove incorrect, could cause our results to differ materially from those expressed or implied by such statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements, including our expectations regarding future revenue and expense levels and capital raising activities, including possible proceeds from our December 2017 Sales Agreement; potential market sizes and demand for our product candidates; the efficacy, safety and intended utilization of our product candidates; the development of our clinical-stage product candidates and our recombinant vaccine and adjuvant technologies; the development of our preclinical product candidates; the conduct, timing and potential results from clinical trials and other preclinical studies; plans for and potential timing of regulatory filings; the expected timing and content of regulatory actions; reimbursement by the Department of Health and Human Services, Biomedical Advanced Research and Development Authority; payments under our license with Wyeth Holdings LLC, a subsidiary of Pfizer Inc. (Wyeth); payments by the Bill & Melinda Gates Foundation (BMGF); our available cash resources and the availability of financing generally, plans regarding partnering activities, business development initiatives and the adoption of stock incentive plans and amendments thereto; the effectiveness, and expected costs and savings, and the timing of such costs and savings, associated with the implementation, of our restructuring efforts, our planned use of the proceeds from this offering, and other factors referenced herein and therein. In addition, forward-looking statements may contain the words “believe,” “may,” “could,” “will,” “possible,” “can,” “estimate,” “continue,” “ongoing,” “consider,” “anticipate,” “intend,” “seek,” “plan,” “project,” “expect,” “should,” “would,” or “assume” or any variations of such words or other words with similar meanings.
Given these uncertainties, you should not place undue reliance on these forward-looking statements. You should read this prospectus supplement, the accompanying prospectus and the documents that we reference in this prospectus supplement or the accompanying prospectus with the understanding that our actual future results may be materially different from what we expect. Except as required by law, we do not undertake any obligation to update or revise any forward-looking statements contained in this prospectus supplement or the accompanying prospectus, whether as a result of new information, future events or otherwise.
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RISK FACTORS
Investing in our securities involves a high degree of risk. For a discussion of the cautionary information you should carefully consider before deciding to purchase any of our securities, please review the risk factors included in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus, including “Part I, Item 1A—Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2017, filed with the SEC on March 14, 2018, as well as other documents that we file with the SEC that are incorporated by reference. The risks and uncertainties described in the documents incorporated by reference are not the only risks and uncertainties we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations. If negative events occur, our business, financial condition, results of operations, and prospects would suffer. In that event, the market price of our common stock could decline, and you may lose all or part of your investment in our common stock.
RISKS RELATED TO OUR BUSINESS AND INDUSTRY
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, 2017 was $1.1 billion. Our revenue for the last three fiscal years was $31.2 million in 2017, $15.4 million in 2016, and $36.3 million in 2015. We may not be successful in entering into strategic alliances or collaborative arrangements with other companies or government agencies that result in significant revenue to offset our expenses. Our net losses for the last three fiscal years were $183.8 million in 2017, $280.0 million in 2016, and $156.9 million in 2015.
Our recent historical losses have resulted predominantly from research and development expenses for our vaccine candidates, manufacturing-related expenses, costs related to protection of our intellectual property and for other general operating expenses. Our expenses have exceeded our revenue since inception, and we believe our expenses will fluctuate over time, and may substantially increase some years, as a result of continuing research and development efforts to support our vaccine development efforts. In 2016, for example, we experienced a significant increase in research and development expenses compared to prior years primarily due to additional RSV F Vaccine clinical trials in older adults and infants via maternal immunization, as well as higher employee-related costs to support development of our RSV F Vaccine and other potential vaccine candidates.
Although certain specified costs associated with the development of our RSV F Vaccine for infants via maternal immunization may be reimbursed under our contract with BMGF, we expect to continue to incur significant operating expenses and anticipate significant losses over time as we seek to:

conduct clinical trials for RSV F Vaccine and other potential vaccine candidates;

conduct preclinical studies for other potential vaccine candidates;

comply with the U.S. Food and Drug Administration, Center for Biologics and Research’s (FDA) manufacturing facility and compliance requirements in anticipation of commercialization;

invest in our manufacturing process for commercial-scale and cost-efficiency; 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 fund our operations. We may never achieve profitability and may not sustain profitability, if achieved.
We have limited financial resources and we may not be able to maintain our current level of operations or be able to fund the further development of our vaccine candidates.
We do not expect to generate revenue from product sales, licensing fees, royalties, milestones, contract research or other sources in amounts sufficient to fully fund our operations for the foreseeable future, and therefore, we will therefore use our cash resources, and expect to require additional funds, to maintain our operations, continue our research and development programs, commence future preclinical studies and
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clinical trials, seek regulatory approvals and manufacture and market our products. We will seek such additional funds through public or private equity or debt financings, collaborative licensing and development arrangements, non-dilutive government contracts and grants and other sources. While we 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 acceptable terms, if 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 general and administrative infrastructure, 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.
Economic 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. Access to capital markets is critical to our ability to operate. Traditionally, biotechnology companies have funded their research and development expenditures through 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 research and development efforts. We require significant capital for research and development for our vaccine candidates and clinical trials. 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. There is no certainty that the capital and credit markets will be available to raise additional capital on favorable terms. If economic conditions become worse, 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 scheduled would be compromised. Moreover, we rely and intend to rely on third-parties, including clinical research 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.
Even with our 2015 Grant Agreement (Grant Agreement) with BMGF, we may not be able to fully fund our RSV F Vaccine for infants via maternal immunization.
The Grant Agreement reimburses a portion of specified expenses associated with the development of our RSV F Vaccine for infants via maternal immunization, and additional activities likely will be needed and BMGF may not reimburse us for any portion of these activities.
The Grant Agreement with BMGF does not assure success in future clinical trials of our RSV F Vaccine for infants via maternal immunization or that the vaccine candidate will be licensed by the FDA.
The Grant Agreement reimburses a portion of specified expenses associated with the development of our RSV F Vaccine for infants via maternal immunization, but we remain fully responsible for conducting these development activities. The Grant Agreement does not guarantee that any of these activities will be successful. Our inability to succeed with key clinical or development activities could jeopardize our ability to obtain FDA licensure to sell this vaccine.
Collaborations and contracts of our wholly owned subsidiary Novavax AB, with regional partners, such as Cadila and BMGF, as well as with international providers, expose us to additional risks associated with doing business outside the U.S.
Swedish-based Novavax AB is a wholly owned subsidiary of Novavax, Inc. We also have formed a joint venture with Cadila Pharmaceuticals Limited (Cadila) in India, have established a clinical development agreement with BMGF and have entered into other agreements and arrangements with companies in other countries. We plan to continue to enter into collaborations or partnerships with companies, non-profit organizations and local governments in various parts of the world. Risks of conducting business outside the U.S. include negative consequences of:
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the costs associated with seeking to comply with multiple regulatory requirements that govern our ability to develop, manufacture and sell products in local markets;

failure to comply with anti-bribery laws such as the U.S. Foreign Corrupt Practices Act and similar anti-bribery laws in other jurisdictions;

existing, new or changes in interpretations of existing trade protections measures, including tariffs, and import and export licensing requirements;

difficulties in and costs of staffing, managing and operating our international operations;

changes in environmental, health and safety laws;

fluctuations in foreign currency exchange rates;

new, changes in or changes in interpretations of tax laws;

political instability and actual or anticipated military or potential conflicts;

economic instability, inflation, recession and interest rate fluctuations;

minimal or diminished protection of intellectual property in many jurisdictions; and

possible nationalization and expropriation.
These risks, individually or in the aggregate, could have a material adverse effect on our business, financial conditions, results of operations and cash flows.
Current or future regional relationships may hinder our ability to engage in larger transactions.
We have entered into regional collaborations to develop our vaccine candidates in certain parts of the world, and we may enter into additional regional collaborations. Our relationships with Cadila and BMGF 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 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 product candidates and a number of events could delay our development efforts and negatively impact our ability to obtain regulatory approval for, and to manufacture, market and sell, a vaccine. Vaccine candidates that initially appear promising often fail to yield successful products. In many cases, preclinical studies or clinical trials will show that a product 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 does not agree with our interpretation of the results, and we may face challenges when scaling-up the production process to commercial levels. 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, which may result in regulatory approvals being suspended, limited to narrow indications 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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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;

pre-clinical 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;

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. and MedImmune, 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.
We are also aware that there are multiple companies with active RSV vaccine programs at various stages of development. Thus, while there is no RSV vaccine currently on the market, there is likely to be significant and consistent competition as these active programs mature. Different RSV vaccines may work better for different segments of the population, so it may be difficult for a single RSV vaccine manufacturer to provide vaccines that are marketable to multiple population segments. Geographic markets are also likely to vary significantly, which may make it difficult to market a single RSV vaccine worldwide. Even if a manufacturer brings an RSV vaccine to license, it is likely that competitors will continue to work on new products that could be more efficacious and/or less expensive. Our RSV vaccine candidate may not be as far along in development as other active RSV vaccine programs about which we are not aware, nor as efficacious as products under development by competing companies.
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, and/or be less expensive and quicker to manufacture. Many of our competitors are working on new products and new generations of current products, intended to be more efficacious than those currently
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marketed. Our nanoparticle seasonal influenza vaccine candidate may not prove to be more efficacious than current products or products under development by our competitors. Further, our manufacturing system may not provide enough savings of time or money to provide the required differentiation for commercial success.
We believe that there are at least two EBOV vaccine candidates currently being tested in late stage clinical trials: one by GlaxoSmithKline in collaboration with the U.S. National Institute of Allergy and Infectious Diseases, and the other by a collaboration of NewLink Genetics, Merck Vaccines USA and the Public Health Agency of Canada. Additional vaccine candidates also are being tested, although in earlier stage clinical trials. Vaccine candidates against EBOV have been in development for more than a decade by large pharmaceutical companies, smaller biotech companies, government agencies and academic labs worldwide, and with the high visibility of the recent West Africa epidemic, development activities are likely to continue and potentially increase.
Regardless of the disease, smaller or early-stage companies and research institutions also may prove to be significant competitors, 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.
If we are unable to attract or retain key management or other personnel, our business, operating results and financial condition could be materially adversely affected.
We depend on our senior executive officers, as well as key scientific and other personnel. The loss of these individuals could harm our business and significantly delay or prevent the achievement of research, development or business objectives. Turnover in key executive positions resulting in lack of management continuity and long-term history with our Company could result in operational and administrative inefficiencies and added costs.
We may not be able to attract qualified individuals for key positions on terms acceptable to us. Competition for qualified employees is intense among pharmaceutical and biotechnology companies, and the loss of qualified employees, or an inability to attract, retain and motivate additional highly skilled employees could hinder our ability to complete clinical trials successfully and develop marketable products.
We also rely from time to time on outside advisors who assist us in formulating our research and development and clinical strategy. We may not be able to attract and retain these individuals on acceptable terms, which could delay our development efforts.
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 in the total amount of  $20 million aggregate for all claims arising from the use of products in clinical trials prior to FDA approval. Coverage is relatively expensive, and the market pricing fluctuates significantly. Therefore, we may not be able to maintain insurance at a reasonable cost. We may not be able to maintain our existing insurance coverage or obtain coverage for the use of our other products in the future. This insurance coverage and our resources may not be sufficient to satisfy all liabilities that result from product liability
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claims. A successful claim may prevent us from obtaining adequate product liability insurance in the future on commercially desirable items, 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.
Regardless of merit or eventual outcome, liability claims may result in:

decreased demand for our products;

impairment of our business reputation;

withdrawal of clinical trial participants;

costs of related litigation;

substantial monetary awards to subjects or other claimants;

loss of revenue; and

inability to commercialize our vaccine candidates.
We may not be able to win government, academic institution or non-profit contracts or grants.
From time to time, we may apply for contracts or grants from government agencies, academic institutions, and non-profit organizations. Such contracts or grants can be highly attractive because they provide capital to fund the ongoing development of our technologies and vaccine candidates without diluting our stockholders. However, there is often significant competition for these contracts or grants. Entities offering contracts or grants may have requirements to apply for or to otherwise be eligible to receive certain contracts or grants that our competitors may be able to satisfy that we cannot. In addition, such entities may make arbitrary decisions as to whether to offer contracts or make grants, to whom the contracts or grants will be awarded and the size of the contracts or grants to each awardee. Even if we are able to satisfy the award requirements, we may not be a successful awardee. Therefore, we may not be able to win any contracts or grants in a timely manner, if at all.
Raising additional capital by issuing securities or through collaboration and licensing arrangements may cause dilution to existing stockholders or require us to relinquish rights to our technologies or vaccine candidates.
If we are unable to partner with a third-party to advance the development of one or more of our vaccine candidates, we will need to raise money through additional debt or equity financings. To the extent that we raise additional capital by issuing equity securities, our stockholders will experience immediate dilution, which may be significant. There is also a risk that such equity issuances may cause an ownership change under the Internal Revenue Code of 1986, as amended, and similar state provisions, thus limiting our ability to use our net operating loss carryforwards and credits. To the extent that we raise additional capital through licensing arrangements or arrangements with collaborative partners, we may be required to relinquish, on terms that may not be favorable to us, rights to some of our technologies or vaccine candidates that we would otherwise seek to develop or commercialize ourselves. In addition, current economic conditions may also negatively affect the desire or ability of potential collaborators to enter into transactions with us. They may also have to delay or cancel research and development projects or reduce their overall budgets.
Our business may be adversely affected if we do not successfully execute our business development initiatives.
We anticipate growing through both internal development projects, as well as external opportunities, which include the acquisition, partnering and in-licensing of products, technologies and companies or the entry into strategic alliances and collaborations. The availability of high quality opportunities is limited, and we may fail to identify candidates that we and our stockholders consider suitable or complete transactions on terms that prove advantageous. In order to pursue such opportunities, we may require significant additional financing, which may not be available to us on favorable terms, if at all. Even if we are able to successfully identify and complete acquisitions, like our business combination with Novavax AB, we may not be able to integrate the assets or take full advantage of the opportunities and, consequently, may not realize the benefits that we expect.
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To effectively manage our current and future potential growth, we will need to continue to enhance our operational, financial and management processes and to effectively expand, train and manage our employee base. Supporting our growth initiatives will require significant expenditures and management resources, including investments in research and development, manufacturing and other areas of our business. If we do not successfully manage our growth and do not successfully execute our growth initiatives, then our business and financial results may be adversely impacted, and we may incur asset impairment or restructuring charges.
Litigation could have a material adverse impact on our results of operation and financial condition.
In addition to intellectual property litigation, from time to time, we may be subject to other litigation. Regardless of the merits of any claims that may be brought against us, litigation could result in a diversion of management’s attention and resources and we may be required to incur significant expenses defending against these claims. If we are unable to prevail in litigation, we could incur substantial liabilities. Where we can make a reasonable estimate of the liability relating to pending litigation and determine that it is probable, we record a related liability. As additional information becomes available, we assess the potential liability and revise estimates as appropriate. However, because of uncertainties relating to litigation, the amount of our estimates could be wrong.
Security breaches and other disruptions could compromise our information and expose us to liability, which would cause our business and reputation to suffer.
In the ordinary course of our business, we collect and store sensitive data, including intellectual property, our proprietary business information and data about our clinical participants, suppliers, and business partners and personally identifiable information. The secure maintenance of this information is critical to our operations and business strategy. Some of this information could be an attractive target of criminal attack by malicious third parties with a wide range of motives and expertise, including organized criminal groups, “hactivists,” patient groups, disgruntled current or former employees and others. Hacker attacks are of ever-increasing levels of sophistication, and despite our security measures, our information technology and infrastructure may be vulnerable to such attacks or may be breached due to employee error or malfeasance. Any such breach could compromise our networks and the information stored there could be accessed, publicly disclosed, lost or stolen. Furthermore, if our systems become compromised, we may not promptly discover the intrusion. Like other companies in our industry, we have experienced attacks to our data and systems, including malware and computer viruses. Attacks could have a material impact on our business, operations or financial results. Any access, disclosure or other loss of information could result in legal claims or proceedings, liability under laws that protect the privacy of personal information, disrupt our operations, and damage our reputation, which could adversely affect our business.
PRODUCT DEVELOPMENT RISKS
Because our vaccine product development efforts depend on new and rapidly evolving technologies, we cannot be certain that our efforts will be successful.
Our vaccine development efforts depend on new, rapidly evolving technologies and on the marketability and profitability of our products. Our development efforts and, if those are successful, commercialization of our vaccines could fail for a variety of reasons, and include the possibility that:

our recombinant nanoparticle vaccine technologies, any or all of the products based on such technologies or our proprietary manufacturing process will be ineffective or unsafe, or otherwise fail to receive necessary regulatory clearances or commercial viability;

we are unable to scale-up our manufacturing capabilities in a cost-effective manner;

the products, if safe and effective, will be difficult to manufacture on a large-scale or uneconomical to market;

our manufacturing facility will fail to continue to pass regulatory inspections;
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proprietary rights of third-parties will prevent us or our collaborators from exploiting technologies, and manufacturing or marketing products; and

third-party competitors will gain greater market share due to superior products or marketing capabilities.
We have not completed the development of vaccine products and we may not succeed in obtaining the FDA licensure necessary to sell such vaccine products.
The development, manufacture and marketing of our pharmaceutical and biological products are subject to government regulation in the U.S. and other countries, including the European Medicines Agency and the Swedish Medical Products Agency with respect to our adjuvant product being developed in Sweden. In the U.S. and most foreign countries, we must complete rigorous preclinical testing and extensive clinical trials that demonstrate the safety and efficacy of a product in order to apply for regulatory approval to market the product. None of our vaccine candidates have yet gained regulatory approval in the U.S. or elsewhere. We also have vaccine candidates in clinical trials and preclinical laboratory or animal studies.
The steps generally required by the FDA before our proposed investigational products may be marketed in the U.S. include:

performance of pre-clinical (animal and laboratory) tests;

submissions to the FDA of an IND, which must become effective before clinical trials may commence;

performance of adequate and well-controlled clinical trials to establish the safety and efficacy of the investigational product in the intended target population;

performance of a consistent and reproducible manufacturing process intended for commercial use, including appropriate manufacturing data and regulatory inspections;

submission to the FDA of a BLA or a NDA; and

FDA approval of the BLA or NDA before any commercial sale or shipment of the product.
The processes are expensive and can take many years to complete, and we may not be able to demonstrate the safety and efficacy of our vaccine candidates to the satisfaction of regulatory authorities. The start of clinical trials can be delayed or take longer than anticipated for many and varied reasons, many of which are out of our control. Safety concerns may emerge that could lengthen the ongoing clinical trials or require additional clinical trials to be conducted. Promising results in early clinical trials may not be replicated in subsequent clinical trials. Regulatory authorities may also require additional testing, and we may be required to demonstrate that our proposed products represent an improved form of treatment over existing therapies, which we may be unable to do without conducting further clinical trials. Moreover, if the FDA or a foreign regulatory body grants regulatory approval of a product, the approval may be limited to specific indications or limited with respect to its distribution. Expanded or additional indications for approved products may not be approved, which could limit our revenue. Foreign regulatory authorities may apply similar limitations or may refuse to grant any approval. Consequently, even if we believe that preclinical and clinical data are sufficient to support regulatory approval for our vaccine candidates, the FDA and foreign regulatory authorities may not ultimately grant approval for commercial sale in any jurisdiction. If our vaccine candidates are not approved, our ability to generate revenue will be limited and our business will be adversely affected.
If we are unable to manufacture our vaccines in sufficient quantities, at sufficient yields or are unable to obtain regulatory approvals for a manufacturing facility for our vaccines, we may experience delays in product development, clinical trials, regulatory approval and commercial distribution.
Completion of our clinical trials and commercialization of our vaccine candidates require access to, or development of, facilities to manufacture our vaccine candidates at sufficient yields and at commercial-scale. We have limited experience manufacturing any of our vaccine candidates in the volumes that will be necessary to support large-scale clinical trials or commercial sales. Efforts to establish these capabilities may not meet initial expectations as to scheduling, scale-up, reproducibility, yield, purity, cost, potency or quality.
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Manufacturing our vaccine candidates involves a complicated process with which we have limited experience. If we are unable to manufacture our vaccine candidates in clinical quantities or, when necessary, in commercial quantities and at sufficient yields, then we must rely on third-parties. Other third-party manufacturers must also receive FDA approval before they can produce clinical material or commercial products. Our vaccines may be in competition with other products for access to these facilities and may be subject to delays in manufacture if third-parties give other products greater priority. We may not be able to enter into any necessary third-party manufacturing arrangements on acceptable terms, or on a timely basis. In addition, we have to enter into technical transfer agreements and share our know-how with the third-party manufacturers, which can be time-consuming and may result in delays.
Like influenza, a licensed RSV vaccine would likely be seasonal in nature. If a seasonal vaccine is not available early enough in the season, we would likely have difficulty selling that vaccine. For these reasons, any delay in the delivery of a seasonal vaccine could result in lower sales volumes, lower sale prices, or no sales. Strains of the seasonal influenza change annually, which means that inventory of seasonal vaccine cannot be sold during a subsequent influenza season. We believe that while RSV strains may also change annually, our RSV F Vaccine is directed at highly-conserved epitopes that are unlikely to change annually, although that has not yet been definitively demonstrated. Any delay in the manufacture of our vaccines could adversely affect our ability to sell the vaccines.
Our reliance on contract manufacturers may adversely affect our operations or result in unforeseen delays or other problems beyond our control. Because of contractual restraints and the limited number of third-party manufacturers with the expertise, required regulatory approvals and facilities to manufacture our bulk vaccines on a commercial-scale, replacement of a manufacturer may be expensive and time-consuming and may cause interruptions in the production of our vaccine. A third-party manufacturer may also encounter difficulties in production. These problems may include:

difficulties with production costs, scale-up and yields;

availability of raw materials and supplies;

quality control and assurance;

shortages of qualified personnel;

compliance with strictly enforced federal, state and foreign regulations that vary in each country where product might be sold; and

lack of capital funding.
As a result, any delay or interruption could have a material adverse effect on our business, financial condition, results of operations and cash flows.
We must identify vaccines for development with our technologies and establish successful third-party relationships.
The near and long-term viability of our vaccine candidates will depend in part on our ability to successfully establish new strategic collaborations with pharmaceutical and biotechnology companies, non-profit organizations and government agencies. Establishing 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 pipeline; 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. If we fail to establish a sufficient number of collaborations or government relationships on acceptable terms, we may not be able to commercialize our vaccine candidates or generate sufficient revenue to fund further research and development efforts.
Even if we establish new collaborations or obtain government funding, these relationships may never result in the successful development or commercialization of any vaccine candidates for several reasons, including the fact that:
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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 vaccine candidates, in a timely manner or at all;

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

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 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.
Our collaborators will be subject to the same regulatory approval of their manufacturing facility and process as us. Before we could begin commercial manufacturing of any of our vaccine candidates, we and our collaborators must pass a pre-approval inspection before FDA approval and comply with the FDA’s GMP regulations. If our collaborators fail to comply with these requirements, our vaccine candidates would not be approved. If our collaborators fail to comply with these requirements after approval, we could be subject to possible regulatory action and may be limited in the jurisdictions in which we are permitted to sell our products.
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 lack of sales, marketing and distribution capabilities, significantly delay the commercialization of our vaccine candidates.
Because we depend on third-parties to conduct some of our laboratory testing, clinical trials, and manufacturing, we may encounter delays in or lose some control over our efforts to develop products.
We are dependent on third-party research organizations to conduct some of our laboratory testing, clinical trials and manufacturing activities. If we are unable to obtain any necessary services on acceptable terms, we may not complete our product development efforts in a timely manner. We may lose some control over these activities and become too dependent upon these parties. These third-parties may not complete testing or manufacturing activities on schedule, within budget, or when we request. We may not be able to secure and maintain suitable research organizations to conduct our laboratory testing, clinical trials and manufacturing activities. We have not manufactured any of our vaccine candidates at a commercial level and may need to identify additional third-party manufacturers to scale-up and manufacture our products.
We are responsible for confirming that each of our clinical trials is conducted in accordance with its general investigational plan and protocol. Moreover, the FDA and foreign regulatory agencies require us to comply with regulations and standards, commonly referred to as good clinical practices, for conducting, recording and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the clinical trial participants are adequately protected. The FDA and foreign regulatory agencies also require us to comply with good manufacturing practices. Our reliance on third-parties does not relieve us of these responsibilities and requirements. These third-parties may not successfully carry out their contractual duties or regulatory obligations or meet expected deadlines. In addition, these third-parties may need to be replaced or the quality or accuracy of the data they obtain may be compromised or the product they manufacture may be contaminated due to the failure to adhere to our clinical and manufacturing protocols, regulatory requirements or for other reasons. In any such event, our preclinical development activities or clinical trials may be extended, delayed, suspended or terminated, and we may not be able to obtain regulatory approval of, or commercially manufacture, our vaccine candidates.
Even if licensed to market, our vaccine products may not be initially or ever profitable.
Whether Novavax makes a profit from the sale of its vaccine products is dependent on a number of variables, including the costs we incur manufacturing, testing and releasing, packaging and shipping such
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vaccine product. The Grant Agreement with BMGF necessitates that we commit to a specific amount of sales in certain specified middle and lower income countries, which may impact our ability to make profits. In addition, we have not yet determined pricing for our vaccine products, which is a complicated undertaking that necessitates both regulatory agency and payor support. We cannot predict when, if at all, our approved vaccine products will be profitable to the Company.
Our collaborations may not be profitable.
We formed CPL Biologicals Private Limited (CPLB) with Cadila in India, but we cannot predict when, if at all, this relationship will lead to additional approved products, sales, or otherwise provide revenue to the Company or become profitable.
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.
Although we have initiated preliminary activities in anticipation of commercialization of our vaccine candidates, we currently have no dedicated sales, marketing or distribution capabilities. As a result, we will depend on collaborations with third-parties that have established distribution systems and sales forces. To the extent that we enter into co-promotion or other licensing arrangements, 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.
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, 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 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.
Unlike RSV, where there is no current vaccine available, there are significant challenges to market seasonal influenza vaccines. For a seasonal vaccine to be accepted in the market, it must demonstrate differentiation from other seasonal vaccines that are currently approved and marketed. This can mean that the vaccine is more effective in certain populations, such as in older adults, or cheaper and quicker to produce. There are no assurances that our influenza vaccine can be differentiated from other influenza vaccines.
If our vaccine candidates do not become widely accepted by physicians, patients, third-party payers and other members of the medical community, our business, financial condition and results of operations could be materially and adversely affected.
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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. We need a secure supply of raw material, as well as back-up suppliers, or our adjuvant products may be delayed.
If reforms in the health care industry make reimbursement for our potential products less likely, the market for our potential products will be reduced, and we could lose potential sources of revenue.
Our success may depend, in part, on the extent to which reimbursement for the costs of vaccines will be available from third-party payers, such as government health administration authorities, private health insurers (including managed care plans), and other organizations. Over the past decade, the cost of health care has risen significantly, and there have been numerous proposals by legislators, regulators and third-party health care payers to curb these costs. Some of these proposals have involved limitations on the amount of reimbursement for certain products. Similar federal or state health care legislation may be adopted in the future and any products that we or our collaborators seek to commercialize may not be considered cost-effective. Adequate third-party insurance coverage may not be available for us to establish and maintain price levels that are sufficient for realization of an appropriate return on our investment in product development. Moreover, 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.
REGULATORY RISKS
We may fail to obtain regulatory approval for our products on a timely basis or comply with our continuing regulatory obligations after approval is obtained.
Delays in obtaining regulatory approval can be extremely costly in terms of lost sales opportunities, loss of any potential marketing advantage of being early to market and increased clinical trial costs. The speed with which we begin and complete our preclinical studies necessary to begin clinical trials, clinical trials and our applications for marketing approval will depend on several factors, including the following:

our ability to manufacture or obtain sufficient quantities of materials for use in necessary pre-clinical studies and clinical trials;

prior regulatory agency review and approval;

approval of the protocol and the informed consent form by the review board of the institution conducting the clinical trial;

the rate of participant enrollment and retention, which is a function of many factors, including the size of the participant population, the proximity of participants to clinical sites, the eligibility criteria for the clinical trial and the nature of the protocol;

negative test results or side effects experienced by clinical trial participants;

analysis of data obtained from preclinical and clinical activities, which are susceptible to varying interpretations and which interpretations could delay, limit or prevent further studies or regulatory approval;

the availability of skilled and experienced staff to conduct and monitor clinical trials and to prepare the appropriate regulatory applications; and

changes in the policies of regulatory authorities for drug or vaccine approval during the period of product development.
We have limited experience in conducting and managing the preclinical studies and clinical trials necessary to obtain regulatory marketing approvals. We may not be permitted to continue or commence additional clinical trials. We also face the risk that the results of our clinical trials may be inconsistent with the results obtained in preclinical studies or clinical trials of similar products or that the results obtained in
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later phases of clinical trials may be inconsistent with those obtained in earlier phases. A number of companies in the biotechnology and product development industry have suffered significant setbacks in advanced clinical trials, even after experiencing promising results in early animal and human testing.
Regulatory agencies may require us or our collaborators to delay, restrict or discontinue clinical trials on various grounds, including a finding that the participants are being exposed to an unacceptable health risk. In addition, we or our collaborators may be unable to submit applications to regulatory agencies within the time frame we currently expect. Once submitted, applications must be approved by various regulatory agencies before we or our collaborators can commercialize the product described in the application. All statutes and regulations governing the conduct of clinical trials are subject to change in the future, which could affect the cost of such clinical trials. Any unanticipated costs or delays in our clinical trials could delay our ability to generate revenue and harm our financial condition and results of operations.
Failure to obtain regulatory approval in foreign jurisdictions would prevent us from marketing our products internationally.
We intend to have our vaccine candidates marketed outside the U.S. In furtherance of this objective, we have entered into relationships with Cadila in India. In order to market our products in the European Union, India, Asia and many other non-U.S. jurisdictions, 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. We may not obtain foreign regulatory approvals on a timely basis, if at all. Approval by a regulatory agency, such as the FDA, does not ensure approval by any other regulatory agencies in other foreign countries. 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.
Even if regulatory approval is received for our vaccine candidates, the later discovery of previously unknown problems with a product, manufacturer or facility may result in restrictions, including withdrawal of the product from the market.
Even if a product gains regulatory approval, such approval is likely to limit the indicated uses for which it may be marketed, and the product and the manufacturer of the product will be subject to continuing regulatory review, including adverse event reporting requirements and the FDA’s general prohibition against promoting products for unapproved uses. Failure to comply with any post-approval requirements can, among other things, result in warning letters, product seizures, recalls, substantial fines, injunctions, suspensions or revocations of marketing licenses, operating restrictions and criminal prosecutions. Any of these enforcement actions, any unanticipated changes in existing regulatory requirements or the adoption of new requirements, or any safety issues that arise with any approved products, could adversely affect our ability to market products and generate revenue and thus adversely affect our ability to continue our business.
We also may be restricted or prohibited from marketing or manufacturing a product, even after obtaining product approval, if previously unknown problems with the product or its manufacture are subsequently discovered and we cannot provide assurance that newly discovered or developed safety issues will not arise following any regulatory approval. With the use of any vaccine by a wide patient population, serious adverse events may occur from time to time that initially do not appear to relate to the vaccine itself, and only if the specific event occurs with some regularity over a period of time does the vaccine become suspect as having a causal relationship to the adverse event. Any safety issues could cause us to suspend or cease marketing of our approved products, possibly subject us to substantial liabilities, and adversely affect our ability to generate revenue and our financial condition.
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
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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 and manufacturing 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 facility in Sweden. 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.
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. However, we believe that we are currently in compliance with all material applicable environmental and occupational health and safety regulations.
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 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 adequate levels of approval, coverage and reimbursement for such products from third-party payers such as:

government health administration authorities such as the Advisory Committee for Immunization Practices of the Center for Disease Control and Prevention (CDC);

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 prescribed 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. Some of these proposed and implemented reforms could result in reduced reimbursement rates for medical products, and while we have no current vaccines available for commercial sale, the impact of such reform could nevertheless adversely affect our business strategy, operations and financial results. For example, the Healthcare Reform Act contained several cost containment measures that could adversely
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affect our future revenue, including, for example, increased drug rebates under Medicaid for brand name prescription drugs, extension of Medicaid rebates to Medicaid managed care organizations, and extension of so-called 340B discounted pricing on pharmaceuticals sold to certain healthcare providers. Additional provisions of the healthcare reform laws that may negatively affect our future revenue and prospects for profitability include the assessment of an annual fee based on our proportionate share of sales of brand name prescription drugs to certain government programs, including Medicare and Medicaid, as well as mandatory discounts on drugs (including vaccines) sold to certain Medicare Part D beneficiaries in the coverage gap (the so-called “donut hole”). Other aspects of healthcare reform, such as expanded government enforcement authority and heightened standards that could increase compliance-related costs, could also affect our business. In addition, we face uncertainties because there are ongoing federal legislative and administrative efforts to repeal, substantially modify or invalidate some or all of the provisions of the Healthcare Reform Act. For example, in 2017, the President announced that his administration will withhold the cost-sharing subsidies paid to health insurance exchange plans serving low-income enrollees. Tax reform legislation was also enacted at the end of 2017 that includes provisions that will affect healthcare insurance coverage and payment, such as the elimination of the tax penalty for individuals who do not maintain sufficient health insurance coverage beginning in 2019 (the so-called “individual mandate”). The Bipartisan Budget Act of 2018 contained various provisions that affect coverage and reimbursement of drugs, including an increase in the mandatory discounts on pharmaceuticals sold to certain Medicare Part D beneficiaries in the coverage gap starting in 2019. We cannot predict the ultimate content, timing or effect of any healthcare reform legislation or the impact of potential legislation on us.
If our product candidates obtain marketing approval, 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., if we obtain approval for any of our product candidates and begin commercializing them, our operations may be directly, or indirectly through our customers, subject to additional healthcare regulation and enforcement by the federal and state governments. In addition to the laws mentioned above, the laws that may affect our ability to operate include:

the Food, Drug and Cosmetic Act, which among other things, strictly regulates drug product marketing and promotion and prohibits manufacturers from marketing such products for off-label use;

the federal anti-kickback law, which prohibits, among other things, persons from soliciting, receiving or providing remuneration, directly or indirectly, to induce the referral for an item or service or the purchasing or ordering of a good or service, for which payment may be made under federal healthcare programs such as Medicare and Medicaid;

federal false claims laws 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 payors that are false or fraudulent;

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 so-called “federal sunshine” law (also known as “open payments”) which requires pharmaceutical and medical device manufacturers to report certain financial interactions to the federal government for re-disclosure to the public;

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;
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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 payor, 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. 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.
INTELLECTUAL PROPERTY RISKS
Our success depends on our ability to maintain the proprietary nature of our technology.
Our success in large part depends on our ability to maintain the proprietary nature of our technology and other trade secrets. 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 350 U.S. patents and corresponding 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 enforced by the federal courts. Therefore, we do not know whether our 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.
There is a risk that third-parties may challenge our existing patents or claim that we are infringing their patents or proprietary rights. We could incur substantial costs in defending patent infringement suits or in filing suits against others to have their patents declared invalid or claim infringement. It is also possible that we may be required to obtain licenses from third-parties to avoid infringing third-party patents or other proprietary rights. We cannot be sure that such third-party licenses would be available to us on acceptable terms, if at all. If we are unable to obtain required third-party licenses, we may be delayed in or prohibited from developing, manufacturing or selling products requiring such licenses.
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-how or other proprietary information.
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 infringe or be claimed to infringe patents 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
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have been filed, but not published that, when issued, could be asserted against us. These third-parties could bring claims against us, and that would cause us to incur substantial expenses and, if successful against us, could cause us to pay substantial damages. Further, if a patent 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 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 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 and other intellectual property rights in the pharmaceutical and biotechnology industries.
We may become involved in litigation to protect or enforce our patents or the patents 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 infringement claims to counter infringement for unauthorized use. This can be expensive, particularly for a company of our size, 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 patents at risk of being invalidated or interpreted narrowly and could put our patent applications at the risk of not issuing.
Even if we are successful, litigation may result in substantial costs and distraction to our management. Even with a broad portfolio, we may not be able, alone or with our collaborators and licensors, to prevent misappropriation of our proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the U.S.
Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. In addition, during the course of this kind of litigation, there could be public announcements of the results of hearings, motions or other interim proceedings or developments. If investors perceive these results to be negative, the market price for our common stock could be significantly harmed.
The scope, validity, and ownership of our patent claims may be challenged in various venues and, if we do not prevail, our ability to exclude competitors may be harmed, potentially reducing our ability to succeed commercially.
We may be subject to a variety of challenges from third-parties that relate to the scope of the claims or to their validity. Such challenges can be mounted in post-grant review, ex parte re-examination, and inter partes review proceedings before the USPTO, or similar adversarial proceedings in other jurisdictions. If we are unsuccessful in any such challenge, the scope of our claims could be narrowed, and the patent or claims thereof could be invalidated. Any such outcome could impair our ability to exclude competitors from the market in those countries, potentially impacting our commercial success.
Our patents may be subject to various challenges related to ownership and inventorship, including interference or derivation proceedings. Third-parties may assert that they are inventors on our patents or that they are owners of the patents. While we perform inventorship analyses to insure that the correct inventors are listed on our patents, we cannot be certain that a court of competent jurisdiction would arrive at the same conclusions we do. If we are unsuccessful in defending against ownership or inventorship
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challenges, a court may require us to list additional inventors, may invalidate the patent, or may transfer ownership of the patent to a third-party. Any of these outcomes may harm our ability to exclude competitors and potentially impact our commercial success. Further, if ownership is transferred to a third-party we may be required to seek a license to those rights to preserve our exclusive ability to practice the invention. Such a license may not be available on commercially reasonable terms, or at all. If we are unable to obtain a license, we may be required to expend time, effort, and other resources to design around the patent. Any such license may be non-exclusive and if a competitor is able to obtain a license from the third-party, our ability to exclude that competitor from the market may be negatively impacted.
Even if we are ultimately successful, defending any such challenges may cause us to incur substantial expenses and may require us to divert substantial financial and management resources that we would otherwise be able to devote to our business.
We may need to license intellectual property from third-parties and, if our right to use the intellectual property we license is affected, our ability to develop and commercialize our vaccine candidates may be harmed.
We have in the past, and we expect in the future to license intellectual property from third-parties and that these licenses will be material to our business. We will not own the patents or patent applications that underlie these licenses, and we will not control the enforcement of the patents. We will rely upon our licensors to properly prosecute and file those patent applications and prevent infringement of those patents.
Our license agreement with Wyeth, which gives us rights to a family of patents and patent applications that are expected to expire in early 2022, covering virus-like particle (VLP) technology for use in human vaccines in certain fields of use, is non-exclusive. If each milestone is achieved for any particular vaccine candidate, we would likely be obligated to pay an aggregate of  $15 million to Wyeth for each vaccine candidate developed and commercialized under the agreement. Achievement of each milestone is subject to many risks, including those described in these risk factors. Annual license fees under the Wyeth agreement aggregate to $0.3 million per year. In September 2015, the Company entered into an amendment to the license agreement with Wyeth. Among other things, the amendment restructured the $3 million milestone payment owed as a result of CPLB’s initiation of a Phase 3 clinical trial for its recombinant trivalent seasonal VLP influenza vaccine candidate in 2014 into a revised milestone payment of  $4 million.
While many of the licenses under which we have rights provide us with rights in specified fields, the scope of our rights under these and other licenses may be subject to dispute by our licensors or third-parties. In addition, our rights to use these technologies and practice the inventions claimed in the licensed patents and patent applications are subject to our licensors abiding by the terms of those licenses and not terminating them. Any of our licenses may be terminated by the licensor if we are in breach of a term or condition of the license agreement, or in certain other circumstances.
Further, any disputes regarding obligations in licenses may require us to take expensive and time-consuming legal action to resolve, and, even if we are successful, may delay our ability to commercialize products and generate revenue. Further, if we are unable to resolve license issues that arise we may lose rights to practice intellectual property that is required to make, use, or sell products. Any such loss could compromise our development and commercialization efforts for current or future product candidates and/or may require additional effort and expense to design around.
Our vaccine candidates and potential vaccine candidates will require several components that may each be the subject of a license agreement. The cumulative license fees and royalties for these components may make the commercialization of these vaccine candidates uneconomical.
If patent laws or the interpretation of patent laws change, our competitors may be able to develop and commercialize our discoveries.
Important legal issues remain to be resolved as to the extent and scope of available patent protection for biopharmaceutical products and processes in the U.S. and other important markets outside the U.S., such as Europe and Japan. In addition, foreign markets may not provide the same level of patent protection as provided under the U.S. patent system. Litigation or administrative proceedings may be necessary to determine the validity and scope of certain of our and others’ proprietary rights. Any such litigation or proceeding may result in a significant commitment of resources in the future and could force us to do one
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or more of the following: cease selling or using any of our products that incorporate the challenged intellectual property, which would adversely affect our revenue; obtain a license from the holder of the intellectual property right alleged to have been infringed, which license may not be available on reasonable terms, if at all; and redesign our products to avoid infringing the intellectual property rights of third-parties, which may be time-consuming or impossible to do. In addition, changes in, or different interpretations of, patent laws in the U.S. and other countries may result in patent laws that allow others to use our discoveries or develop and commercialize our products. We cannot provide assurance that the patents we obtain or the unpatented technology we hold will afford us significant commercial protection.
RISKS RELATED TO OUR CONVERTIBLE SENIOR NOTES
Servicing our 3.75% convertible senior unsecured notes due 2023 (the “Notes”) requires a significant amount of cash, and we may not have sufficient cash flow to pay our debt.
In 2016, we issued $325 million aggregate principal amount of Notes. Our ability to make scheduled payments of the principal of, to pay interest on, or to refinance our indebtedness, including the Notes, depends on our future performance, which is subject to economic, financial, competitive and other factors beyond our control. We do not expect our business to be able to generate cash flow from operations, in the foreseeable future, sufficient to service our debt and make necessary capital expenditures and may therefore be required to adopt one or more alternatives, such as selling assets, restructuring debt or obtaining additional equity capital on terms that may be onerous or highly dilutive. Our ability to refinance our indebtedness, which is non-callable and matures in 2023, will depend on the capital markets and our financial condition at such time. We may not be able to engage in any of these activities or engage in these activities on desirable terms, which could result in a default on our debt obligations, and limit our flexibility in planning for and reacting to changes in our business.
We may not have the ability to raise the funds necessary to repurchase the Notes as required upon a fundamental change, and our future debt may contain limitations on our ability to repurchase the Notes.
Holders of the Notes will have the right to require us to repurchase their Notes for cash upon the occurrence of a fundamental change at a fundamental change repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest, if any. A fundamental change may also constitute an event of default or prepayment under, and result in the acceleration of the maturity of, our then-existing indebtedness. We cannot assure you that we will have sufficient financial resources, or will be able to arrange financing, to pay the fundamental change repurchase price in cash with respect to any Notes surrendered by holders for repurchase upon a fundamental change. In addition, restrictions in our then existing credit facilities or other indebtedness, if any, may not allow us to repurchase the Notes upon a fundamental change. Our failure to repurchase the Notes upon a fundamental change when required would result in an event of default with respect to the Notes which could, in turn, constitute a default under the terms of our other indebtedness, if any. If the repayment of the related indebtedness were to be accelerated after any applicable notice or grace periods, we may not have sufficient funds to repay the indebtedness and repurchase the Notes.
Capped call transactions entered into in connection with our Notes may affect the value of our common stock.
In connection with our Notes, we entered into capped call transactions (the “capped call transactions”) with certain financial institutions. The capped call transactions are expected to generally reduce the potential dilution upon conversion of the Notes into shares of our common stock.
In connection with establishing their initial hedges of the capped call transactions, these financial institutions or their respective affiliates entered into various derivative transactions with respect to our common stock and/or to purchase our common stock. The financial institutions, or their respective affiliates, may modify their hedge positions by entering into or unwinding various derivatives with respect to our common stock and/or purchasing or selling our common stock or other securities of ours in secondary market transactions prior to the maturity of the Notes. This activity could also cause or avoid an increase or a decrease in the market price of our common stock or the Notes, which could affect the value of our common stock.
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RISKS RELATED TO OUR COMMON STOCK AND ORGANIZATIONAL STRUCTURE
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.
Our stock price has been highly volatile. The stock market in general and the market for biotechnology companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. From January 1, 2018 through March 31, 2018, the closing sale price of our common stock has been as low as $1.29 per share and as high as $2.42 per share. The market price of our common stock may be influenced by many factors, including:

future announcements about us or our collaborators or competitors, including the results of testing, technological innovations or new commercial products;

clinical trial results;

depletion of our cash reserves;

sale of equity securities or issuance of additional debt;

announcement by us of significant strategic partnerships, collaborations, joint ventures, capital commitments or acquisitions;

changes in government regulations;

impact of competitor successes and in particular development success of vaccine candidates that compete with our own vaccine candidates;

developments in our relationships with our collaboration partners;

announcements relating to health care reform and reimbursement levels for new vaccines and other matters affecting our business and results, regardless of accuracy;

sales of substantial amounts of our stock by existing stockholders (including stock by insiders or 5% stockholders);

development, spread or new announcements related to pandemic diseases;

litigation;

public concern as to the safety of our products;

significant set-backs or concerns with the industry or the market as a whole;

regulatory inquiries, reviews and potential action, including from the FDA or the SEC;

recommendations by securities analysts or changes in earnings estimates; and

the other factors described in this Risk Factors section.
In addition, the stock market in general, and the market for biotechnology companies in particular, have experienced extreme price and volume fluctuations that have particularly affected the market price for many of those companies. These fluctuations have often been unrelated to the operating performance of these companies. These broad market fluctuations may cause the market price of our common stock to be lower or more volatile than expected.
The Nasdaq Global Select Market has a listing requirement; if a participating company no longer meets such requirements and fails to correct the listing deficiency, its stock may be delisted.
The Nasdaq Global Select Market (“Nasdaq”), on which our common stock is listed and traded, has listing requirements that include a $1 minimum closing bid price requirement. If we fail to satisfy this or other listing requirements, Nasdaq may elect, subject to any potential cure periods, to initiate a process that may delist our common stock. Should such a delisting occur, it may adversely impact the liquidity and price of our common stock, impede our ability to raise capital and would constitute a fundamental change under our Notes.
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Provisions of our Second Amended and Restated Certificate of Incorporation and Amended and Restated By-Laws and Delaware law could delay or prevent the acquisition of the Company, even if such acquisition would be beneficial to stockholders, and could impede changes in our Board.
Provisions in our organizational documents could hamper a third-party’s attempt to acquire, or discourage a third-party from attempting to acquire control of, the Company. Stockholders who wish to participate in these transactions may not have the opportunity to do so. Our organizational documents also could limit the price investors are willing to pay in the future for our securities and make it more difficult to change the composition of our Board in any one year. Certain provisions include the right of the existence of a staggered board with three classes of directors serving staggered three-year terms and advance notice requirements for stockholders to nominate directors and make proposals.
As a Delaware corporation, we are also afforded the protections of Section 203 of the Delaware General Corporation Law, which will prevent us from engaging in a business combination with a person who acquires at least 15% of our common stock for a period of three years from the date such person acquired such common stock, unless advance board or stockholder approval was obtained.
Any delay or prevention of a change of control transaction or changes in our Board or management could deter potential acquirers or prevent the completion of a transaction in which our stockholders could receive a substantial premium over the then current market price for their shares.
We have never paid dividends on our capital stock, and we do not anticipate paying any such dividends in the foreseeable future.
We have never paid cash dividends on our common stock. We currently anticipate that we will retain all of our earnings for use in the development of our business and do not anticipate paying any cash dividends in the foreseeable future. As a result, capital appreciation, if any, of our common stock would be the only source of gain for stockholders until dividends are paid, if at all.
ADDITIONAL RISKS RELATED TO THIS OFFERING
You will experience immediate and substantial dilution.
Since the price per share of our common stock being offered is substantially higher than the net tangible book value per share of our common stock, you will suffer substantial dilution in the net tangible book value of the common stock you purchase in this offering. Based on the assumed public offering of            shares at                       per share, and without deducting underwriting discounts and commissions, but after deducting estimated offering expenses payable by us, and based on a net tangible book value of our common stock of  $(0.50) per share as of December 31, 2017, after giving effect to this offering, if you purchase shares of common stock in this offering, you will suffer immediate and substantial dilution of  $     per share in the net tangible book value of common stock. The exercise of our outstanding stock options and vesting of our outstanding restricted stock units could result in further dilution of your investment. See the section entitled “Dilution” below for a more detailed illustration of the dilution you would incur if you participate in this offering.
You may experience future dilution as a result of future equity offerings.
In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering.
We have broad discretion in how we use the net proceeds of this offering and our other resources, and we may not use these proceeds effectively or in ways with which you agree.
Our management will have broad discretion as to the application of the net proceeds of this offering and our other resources and could use them for purposes other than those contemplated at the time of this
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offering. Our stockholders may not agree with the manner in which our management chooses to allocate and spend the net proceeds and our other resources. Moreover, our management may use the net proceeds and our other resources for corporate purposes that may not improve our results of operations or enhance the value of our common stock. Our failure to apply these funds effectively could have a material adverse effect on our business and cause the price of our common stock to decline.
If securities and/or industry analysts fail to continue publishing research about our business, if they change their recommendations adversely or if our results of operations do not meet their expectations, our stock price and trading volume could decline.
The trading market for our common stock will be influenced by the research and reports that industry or securities analysts publish about us or our business. If one or more of these analysts cease coverage of our company or fail to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline. In addition, it is likely that in some future period our operating results will be below the expectations of securities analysts or investors. If one or more of the analysts who cover us downgrade our stock, or if our results of operations do not meet their expectations, our stock price could decline.
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USE OF PROCEEDS
We estimate that the net proceeds we will receive from this offering will be approximately $         , after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us. If the underwriters exercise their option to purchase additional shares in full, we estimate that the net proceeds from this offering will be $         .
We intend to use the net proceeds from this offering for general corporate purposes, including but not limited to working capital, capital expenditures, research and development expenditures, clinical trial expenditures, as well as acquisitions and other strategic purposes.
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DILUTION
If you invest in our common stock, your interest will be diluted to the extent of the difference between the price per share you pay in this offering and the net tangible book value per share of our common stock immediately after this offering. Our net tangible book value of our common stock as of December 31, 2017 was approximately $(163.2) million, or approximately $(0.50) per share of common stock based upon 323,229,390 shares outstanding. Net tangible book value per share is equal to our total tangible assets, less our total liabilities, divided by the total number of shares outstanding as of December 31, 2017.
After giving effect to the sale by us of            shares of common stock at the price of  $     per share, without any deduction for underwriting discounts and commissions, but after deducting estimated offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2017 would have been approximately $     million, or $     per share. This would represent an immediate increase in net tangible book value of  $     per share to our existing stockholders and an immediate dilution in net tangible book value of  $     per share to new investors purchasing our common stock in this offering at the assumed public offering price. The following table illustrates this calculation on a per share basis:
Offering price per share
$     
Net tangible book value per share as of December 31, 2017
$ (0.50)
Increase in net tangible book value per share attributable to the offering
$     
As-adjusted net tangible book value per share after giving effect to the offering
$     
Dilution in net tangible book value per share to new investors in the offering
$     
The information discussed above is illustrative only and will adjust based on the actual public offering price and other terms of this offering determined at pricing.
The foregoing table excludes the following, each as of December 31, 2017:

46,494,649 shares of our common stock reserved for issuance upon the exercise of outstanding stock options at a weighted average exercise price of  $3.51 per share;

808,425 shares of our common stock reserved for issuance under our Employee Stock Purchase Plan; and

2,279,280 shares of our common stock reserved for issuance under our 2015 Stock Incentive Plan, as amended.
This discussion of dilution, and the table quantifying it, assumes no exercise of any outstanding options to purchase shares of our common stock as of December 31, 2017 and no issuance of up to           shares of common stock that we may sell to the underwriters upon exercise of their option to purchase additional shares of common stock. The exercise of outstanding options to purchase shares of our common stock having an exercise price less than the public offering price would increase the dilutive effect to new investors.
If the underwriters exercise in full their option to purchase           additional shares of common stock at                       per share, the pro forma as adjusted net tangible book value after this offering would be approximately $     per share, representing an increase in net tangible book value of approximately $     per share to existing stockholders and immediate dilution in net tangible book value of approximately $     per share to investors purchasing our common stock in this offering at the public offering price.
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MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR
NON-U.S. HOLDERS OF COMMON STOCK
The following is a summary of certain material U.S. federal income and estate tax considerations relating to the purchase, ownership and disposition of our common stock by Non-U.S. Holders (defined below), but does not purport to be a complete analysis of all the potential tax considerations. This summary is based upon the Internal Revenue Code of 1986, as amended (the “Code”), the Treasury regulations promulgated or proposed thereunder and administrative and judicial interpretations thereof, all as of the date hereof and all of which are subject to change at any time, possibly on a retroactive basis. This summary is limited to the tax consequences to those persons who hold our common stock as capital assets within the meaning of Section 1221 of the Code.
This summary does not purport to deal with all aspects of U.S. federal income and estate taxation that might be relevant to particular Non-U.S. Holders in light of their particular investment circumstances or status, nor does it address specific tax considerations that may be relevant to particular persons (including, for example, financial institutions, broker-dealers, insurance companies, partnerships or other pass-through entities, certain U.S. expatriates and certain former citizens or long-term residents of the United States, tax-exempt organizations, “entities treated as financial conduits for U.S. federal income tax purposes, controlled foreign corporations,” “passive foreign investment companies,” corporations that accumulate earnings to avoid U.S. federal income tax, or persons in special situations, such as those who have elected to mark securities to market or those who hold common stock as part of a straddle, hedge, conversion transaction or other integrated investment). In addition, this summary does not address U.S. federal alternative minimum, the unearned income Medicare contribution tax, certain estate and gift tax considerations or considerations under the tax laws of any state, local or non-U.S. jurisdiction.
This summary is for general information only. Non-U.S. Holders are urged to consult their own tax advisors concerning the U.S. federal income and estate taxation, state, local and non-U.S. taxation and other tax consequences to them of the purchase, ownership and disposition of our common stock, as well as the application of state, local and non-U.S. income and other tax laws.
For purposes of this summary, a “Non-U.S. Holder” means a beneficial owner of common stock that for U.S. federal income tax purposes is not:

an individual who is a citizen or resident of the U.S.,

a corporation (or other entity taxable as a corporation) created or organized under the laws of the U.S., any state thereof, or the District of Columbia,

an estate the income of which is subject to U.S. federal income tax regardless of its source, or

a trust if  (a) a court within the U.S. is able to exercise primary supervision over the administration of the trust, and one or more U.S. persons have the authority to control all substantial decisions of the trust, or (b) a valid election to be treated as a U.S. person is in effect with respect to such trust.
If a partnership, or an entity or arrangement treated as a partnership for U.S. federal income tax purposes, holds common stock, the tax treatment of a partner in the partnership generally will depend upon the partner’s tax status and upon the activities of the partnership. Accordingly, partnerships and other entities that are classified as partnerships for U.S. federal income tax purposes that hold our common stock and partners in such partnerships should consult their tax advisors.
Distributions on Our Common Stock
We do not currently expect to pay dividends. In the event that we do make a distribution of cash or property with respect to our common stock, any such distributions will be treated as a dividend for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, if any (as determined under U.S. federal income tax principles). If a distribution exceeds our current and accumulated earnings and profits, the excess will be treated first as a tax-free return of capital to the extent of the Non-U.S. Holder’s tax basis in our common stock and thereafter as capital gain from the sale or exchange of such stock. Any such distribution would also be subject to the discussion below under the
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sections titled “Backup Withholding and Information Reporting” and “Additional Withholding and Information Reporting Requirements.” Dividends paid to a Non-U.S. Holder generally will be subject to a 30% U.S. federal withholding tax unless such Non-U.S. Holder provides us or our agent, as the case may be, with a properly executed:
1.
U.S. Internal Revenue Service (“IRS”) Form W-8BEN or W-8BEN-E (or successor form) claiming, under penalties of perjury, a reduction in withholding under an applicable income tax treaty, or
2.
IRS Form W-8ECI (or successor form) stating that a dividend paid on common stock is not subject to withholding tax because it is effectively connected with a U.S. trade or business of the Non-U.S. Holder (in which case such dividend generally will be subject to regular graduated U.S. tax rates as described below).
The certification requirement described above also may require a Non-U.S. Holder that provides an IRS form or that claims treaty benefits to provide its U.S. taxpayer identification number. These certifications must be provided to the applicable withholding agent prior to the payment of dividends and must be updated periodically. Special certification and other requirements apply in the case of certain Non-U.S. Holders that are intermediaries or pass-through entities for U.S. federal income tax purposes.
Each Non-U.S. Holder is urged to consult its tax advisor about the specific methods for satisfying these requirements. A claim for exemption will not be valid if the person receiving the applicable form has actual knowledge or reason to know that the statements on the form are false.
If dividends are effectively connected with a U.S. trade or business of the Non-U.S. Holder (and, if required by an applicable income tax treaty, attributable to a U.S. permanent establishment), the Non-U.S. Holder, although exempt from the withholding tax described above (provided that the certifications described above are satisfied), will be subject to U.S. federal income tax on such dividends on a net income basis in the same manner as if it were a resident of the United States. In addition, if such Non-U.S. Holder is a non-U.S. corporation and dividends are effectively connected with its U.S. trade or business (and, if required by an applicable income tax treaty, attributable to a U.S. permanent establishment), such Non-U.S. Holder may be subject to an additional “branch profits tax” equal to 30% (unless reduced by an applicable income treaty) in respect of such effectively-connected income.
If a Non-U.S. Holder is eligible for a reduced rate of U.S. federal withholding tax pursuant to an income tax treaty, such holder may obtain a refund or credit of any excess amount withheld by timely filing an appropriate claim for refund with the IRS.
Disposition of Our Common Stock
Subject to the discussion below under the section titled “Additional Withholding and Information Reporting Requirements,” in general, a Non-U.S. Holder will not be subject to U.S. federal income tax or withholding tax on gain recognized on a sale, exchange or other taxable disposition of a share of our common stock, unless:

the gain is effectively connected with a trade or business of the Non-U.S. Holder in the United States (and, if required by an applicable income tax treaty, attributable to a U.S. permanent establishment);

the Non-U.S. Holder is a nonresident alien who is present in the United States for 183 days or more in the taxable year of the disposition and meets certain other conditions; or

we are or have been a “United States real property holding corporation,” as defined in the Code (a “USRPHC”), at any time within the shorter of the five-year period preceding the disposition and the Non-U.S. Holder’s holding period in the share of our common stock.
We believe we are not, and do not anticipate becoming, a USRPHC. However, because the determination of whether we are a USRPHC depends on the fair market value of our U.S. real property relative to the fair market value of other business assets, there can be no assurance that we will not become a USRPHC in the future. Even if we become a USRPHC, a Non-U.S. Holder would not be subject to U.S. federal income tax on a sale, exchange or other taxable disposition of our common stock so long as our
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common stock continues to be regularly traded on an established securities market and such Non-U.S. Holder does not own and is not deemed to own (directly, indirectly or constructively) more than 5% of our common stock at any time during the shorter of the five year period ending on the date of disposition and the holder’s holding period.
If a Non-U.S. Holder is engaged in a trade or business in the U.S. and gain recognized by the Non-U.S. Holder on a sale or other disposition of our common stock is effectively connected with the conduct of such trade or business, the Non-U.S. Holder will generally be subject to regular U.S. income tax as if the Non-U.S. Holder were a U.S. person, subject to an applicable income tax treaty providing otherwise. Additionally, a non-U.S. corporation may also, under certain circumstances, be subject to an additional “branch profits tax” imposed at a rate of 30% (or, if applicable, a lower income tax treaty rate). Non-U.S. Holders whose gain from dispositions of our common stock may be effectively connected with the conduct of a trade or business in the United States are urged to consult their tax advisors with respect to the U.S. tax consequences of the purchase, ownership and disposition of our common stock.
A nonresident alien who is subject to U.S. federal income tax because such individual was present in the United States for 183 days or more in the taxable year of the taxable disposition of our common stock will be subject to a flat 30% tax on the gain derived from such disposition, which may be offset by certain U.S. source capital losses provided the Non-U.S. Holder timely files U.S. federal income tax returns with respect to such losses.
Backup Withholding and Information Reporting
Backup withholding tax is imposed on dividends and certain other types of payments to certain U.S. persons (currently at a rate of 28%). In general, backup withholding tax will not apply to payments of dividends on common stock or proceeds from the sale of common stock payable to a Non-U.S. Holder if the certification described above under “ Distributions on Our Common Stock” is duly provided by such Non-U.S. Holder or the Non-U.S. Holder otherwise establishes an exemption, provided that the payor does not have actual knowledge or reason to know that the Non-U.S. Holder is a U.S. person or that the conditions of any claimed exemption are not satisfied. Certain information reporting may still apply to distributions even if an exemption from backup withholding is established. Generally, we must report annually to the IRS and each Non-U.S. Holder certain information including the Non-U.S. Holder’s name, address and taxpayer identification number, the aggregate amount of distributions on our common stock paid to that Non-U.S. Holder during the calendar year and the amount of tax withheld, if any. Copies of any information returns reporting the distributions to a Non-U.S. Holder and any withholding also may be made available to the tax authorities in the country in which a Non-U.S. Holder resides under the provisions of an applicable income tax treaty.
Backup withholding is not an additional tax and any amounts withheld under the backup withholding tax rules from a payment to a Non-U.S. Holder will be allowed as a refund or a credit against such Non-U.S. Holder’s U.S. federal income tax liability, provided that the requisite procedures are followed.
Non-U.S. Holders are urged to consult their own tax advisors regarding their particular circumstances and the availability of and procedure for obtaining an exemption from backup withholding.
Additional Withholding and Information Reporting Requirements
Sections 1471 through 1474 of the Code and related Treasury Regulations (commonly referred to as “FATCA”) will impose, in certain circumstances, U.S. federal withholding at a rate of 30% on payments on payments of dividends on, or gross proceeds from the sale or other disposition of, our common stock or warrants paid to certain foreign entities, unless (i) if the foreign entity is a “foreign financial institution,” such foreign entity undertakes certain due diligence, reporting, withholding, and certification obligations, (ii) if the foreign entity is not a “foreign financial institution,” such foreign entity either certifies that it does not have any “substantial United States owners” (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (iii) the foreign entity otherwise qualifies from an exemption these rules. Under applicable U.S. Treasury Regulations, withholding under FATCA currently applies to (1) dividends on our common stock, and (2) gross proceeds from the sale or other disposition of our common stock on or after January 1, 2019. A Non-U.S. holder that is not subject to
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FATCA withholding generally may certify its exempt status by furnishing a properly executed IRS Form W-8BEN or Form W-8BEN-E (or successor form), as applicable. Under certain circumstances, a non-U.S. holder may be eligible for refunds or credits of the tax. Certain intergovernmental agreements between the United States and other countries may modify these rules. Non-U.S. holders should consult their own tax advisors regarding the possible implications of this legislation on their investment in our common stock and the entities through which they hold our common stock, including, without limitation, the process and deadlines for meeting the applicable requirements to prevent the imposition of the 30% withholding tax under FATCA.
U.S. Federal Estate Tax
Common stock owned or treated as owned by an individual who is a Non-U.S. Holder at the time of death generally will be included in the individual’s gross estate for U.S. federal estate tax purposes and may be subject to U.S. federal estate tax unless an applicable estate or other tax treaty provides otherwise.
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Underwriting
Citigroup Global Markets Inc. and Piper Jaffray & Co. are acting as joint book-running managers of the offering and as representatives of the underwriters named below. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has severally and not jointly agreed to purchase, and we have agreed to sell to that underwriter, the number of shares set forth opposite the underwriter’s name.
Underwriters
Number of shares
Citigroup Global Markets Inc.
               ​
Piper Jaffray & Co.
Total
The underwriting agreement provides that the obligations of the underwriters to purchase the shares included in this offering are subject to approval of legal matters by counsel and to other conditions. The underwriters are obligated to purchase all the shares (other than those covered by the underwriters’ option to purchase additional shares described below) if they purchase any of the shares.
Shares sold by the underwriters to the public will initially be offered at the public offering price set forth on the cover of this prospectus supplement. Any shares sold by the underwriters to securities dealers may be sold at a discount from the public offering price not to exceed $ per share. If all the shares are not sold at the initial offering price, the underwriters may change the offering price and the other selling terms.
If the underwriters sell more shares than the total number set forth in the table above, we have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to additional shares at the public offering price less the underwriting discounts and commissions. To the extent the option is exercised, each underwriter must purchase a number of additional shares approximately proportionate to that underwriter’s initial purchase commitment. Any shares issued or sold under the option will be issued and sold on the same terms and conditions as the other shares that are the subject of this offering.
We and all of our directors and executive officers have agreed that, for a period of 60 days from the date of this prospectus supplement, we and they will not, without the prior written consent of the representatives, dispose of or hedge any shares or any securities convertible into or exchangeable for our common stock. The representatives in their sole discretion may release any of the securities subject to these lock-up agreements at any time without notice.
Our common stock is listed on the Nasdaq Global Select Market under the symbol “NVAX.”
The following table shows the underwriting discounts and commissions that we are to pay to the underwriters in connection with this offering. These amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares.
Paid by Novavax, Inc.
No Exercise
Full Exercise
Per share
$                 $                
Total
$ $
We estimate that our total expenses of this offering will be approximately $100,000. The underwriters have agreed to reimburse us for certain of our expenses associated with this offering. Seaport Global Securities LLC (“Seaport”) is acting as financial advisor in connection with this offering, for which we will pay Seaport an advisory fee of  $50,000.
In connection with the offering, the underwriters may purchase and sell shares in the open market. Purchases and sales in the open market may include short sales, purchases to cover short positions, which may include purchases pursuant to the underwriters’ option to purchase additional shares, and stabilizing purchases.
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Short sales involve secondary market sales by the underwriters of a greater number of shares than they are required to purchase in the offering.

“Covered” short sales are sales of shares in an amount up to the number of shares represented by the underwriters’ option to purchase additional shares.

“Naked” short sales are sales of shares in an amount in excess of the number of shares represented by the underwriters’ option to purchase additional shares.

Covering transactions involve purchases of shares either pursuant to the underwriters’ option to purchase additional shares or in the open market in order to cover short positions.

To close a naked short position, the underwriters must purchase shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering.

To close a covered short position, the underwriters must purchase shares in the open market or must exercise the option to purchase additional shares. In determining the source of shares to close the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the underwriters’ option to purchase additional shares.

Stabilizing transactions involve bids to purchase shares so long as the stabilizing bids do not exceed a specified maximum.
Purchases to cover short positions and stabilizing purchases, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the market price of the shares. They may also cause the price of the shares to be higher than the price that would otherwise exist in the open market in the absence of these transactions. The underwriters may conduct these transactions on the Nasdaq Global Select Market, in the over-the-counter market or otherwise. If the underwriters commence any of these transactions, they may discontinue them at any time.
In addition, in connection with this offering, some of the underwriters (and selling group members) may engage in passive market making transactions in the shares on the Nasdaq Global Select Market, prior to the pricing and completion of the offering. Passive market making consists of displaying bids on the Nasdaq Global Select Market no higher than the bid prices of independent market makers and making purchases at prices no higher than those independent bids and effected in response to order flow. Net purchases by a passive market maker on each day are limited to a specified percentage of the passive market maker’s average daily trading volume in the shares during a specified period and must be discontinued when that limit is reached. Passive market making may cause the price of the shares to be higher than the price that otherwise would exist in the open market in the absence of those transactions. If the underwriters commence passive market making transactions, they may discontinue them at any time.
Conflicts of Interest
The underwriters are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, principal investment, hedging, financing and brokerage activities. The underwriters and their respective affiliates have in the past performed commercial banking, investment banking and advisory services for us from time to time for which they have received customary fees and reimbursement of expenses and may, from time to time, engage in transactions with and perform services for us in the ordinary course of their business for which they may receive customary fees and reimbursement of expenses. In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (which may include bank loans and/or credit default swaps) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities and instruments. Such investments and securities activities may involve securities and/or instruments of ours or
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our affiliates. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.
We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the underwriters may be required to make because of any of those liabilities.
Sales Outside the United States
No action has been taken in any jurisdiction (except in the United States) that would permit a public offering of our common stock, or the possession, circulation or distribution of this prospectus supplement or any other material relating to us or our common stock in any jurisdiction where action for that purpose is required. Accordingly, the shares of common stock may not be offered or sold, directly or indirectly, and neither this prospectus supplement nor any other offering material or advertisements in connection with our common stock may be distributed or published, in or from any country or jurisdiction, except in compliance with any applicable rules and regulations of any such country or jurisdiction.
The underwriters may arrange to sell the common stock offered hereby in certain jurisdictions outside the United States, either directly or through affiliates, where it is permitted to do so.
Notice to Prospective Investors in Canada
The shares may be sold in Canada only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.
Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.
Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.
Notice to Prospective Investors in the European Economic Area
In relation to each member state of the European Economic Area that has implemented the Prospectus Directive (each, a relevant member state), with effect from and including the date on which the Prospectus Directive is implemented in that relevant member state (the relevant implementation date), an offer of shares described in this prospectus supplement may not be made to the public in that relevant member state other than:

to any legal entity which is a qualified investor as defined in the Prospectus Directive;

to fewer than 100 or, if the relevant member state has implemented the relevant provision of the 2010 PD Amending Directive, 150 natural or legal persons (other than qualified investors as defined in the Prospectus Directive), as permitted under the Prospectus Directive, subject to obtaining the prior consent of the relevant Dealer or Dealers nominated by us for any such offer; or

in any other circumstances falling within Article 3(2) of the Prospectus Directive,
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provided that no such offer of shares shall require us or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Directive.
For purposes of this provision, the expression an “offer of securities to the public” in any relevant member state means the communication in any form and by any means of sufficient information on the terms of the offer and the shares to be offered so as to enable an investor to decide to purchase or subscribe for the shares, as the expression may be varied in that member state by any measure implementing the Prospectus Directive in that member state, and the expression “Prospectus Directive” means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the relevant member state) and includes any relevant implementing measure in the relevant member state. The expression 2010 PD Amending Directive means Directive 2010/73/EU.
The sellers of the shares have not authorized and do not authorize the making of any offer of shares through any financial intermediary on their behalf, other than offers made by the underwriters with a view to the final placement of the shares as contemplated in this prospectus supplement. Accordingly, no purchaser of the shares, other than the underwriters, is authorized to make any further offer of the shares on behalf of the sellers or the underwriters.
Notice to Prospective Investors in the United Kingdom
This prospectus supplement and the accompanying prospectus are only being distributed to, and is only directed at, persons in the United Kingdom that are qualified investors within the meaning of Article 2(1)(e) of the Prospectus Directive that are also (i) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”) or (ii) high net worth entities, and other persons to whom it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order (each such person being referred to as a “relevant person”). This prospectus supplement and its contents are confidential and should not be distributed, published or reproduced (in whole or in part) or disclosed by recipients to any other persons in the United Kingdom. Any person in the United Kingdom that is not a relevant person should not act or rely on this document or any of its contents.
This prospectus supplement and the accompanying prospectus is are only being distributed in the United Kingdom to, and are only directed at, (a) investment professionals falling within both Article 14(5) of the Financial Services and Markets Act 2000 (Promotion of Collective Investment Schemes) Order 2001, as amended (the “CIS Promotion Order”) and Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the “General Promotion Order”), and (b) high net worth companies and other persons falling within both Article 22(2)(a) to (d) of the CIS Promotion Order and Article 49(2)(a) to (d) of the General Promotion Order (all such persons together being referred to as “relevant persons”).
Notice to Prospective Investors in France
Neither this prospectus supplement nor any other offering material relating to the shares described in this prospectus supplement has been submitted to the clearance procedures of the Autorité des Marchés Financiers or of the competent authority of another member state of the European Economic Area and notified to the Autorité des Marchés Financiers. The shares have not been offered or sold and will not be offered or sold, directly or indirectly, to the public in France. Neither this prospectus supplement nor any other offering material relating to the shares has been or will be:

released, issued, distributed or caused to be released, issued or distributed to the public in France; or

used in connection with any offer for subscription or sale of the shares to the public in France.
Such offers, sales and distributions will be made in France only:

to qualified investors (investisseurs qualifiés) and/or to a restricted circle of investors (cercle restraint d’investisseurs), in each case investing for their own account, all as defined in, and in accordance with articles L.411-2, D.411-1, D.411-2, D.734-1, D.744-1, D.754-1 and D.764-1 of the French Code monétaire et financier;
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to investment services providers authorized to engage in portfolio management on behalf of third parties; or

in a transaction that, in accordance with article L.411-2-II-1°-or-2°-or 3° of the French Code monétaire et financier and article 211-2 of the General Regulations (Règlement Général) of the Autorité des Marchés Financiers, does not constitute a public offer (appel public à l’épargne).
The shares may be resold directly or indirectly, only in compliance with articles L.411-1, L.411-2, L.412-1 and L.621-8 through L.621-8-3 of the French Code monétaire et financier.
Notice to Prospective Investors in Hong Kong
The shares may not be offered or sold in Hong Kong by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap. 32, Laws of Hong Kong), or (ii) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap. 32, Laws of Hong Kong) and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.
Notice to Prospective Investors in Japan
The shares offered in this prospectus supplement have not been and will not be registered under the Financial Instruments and Exchange Law of Japan. The shares have not been offered or sold and will not be offered or sold, directly or indirectly, in Japan or to or for the account of any resident of Japan (including any corporation or other entity organized under the laws of Japan), except (i) pursuant to an exemption from the registration requirements of the Financial Instruments and Exchange Law and (ii) in compliance with any other applicable requirements of Japanese law.
Notice to Prospective Investors in Singapore
This prospectus supplement has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (the “SFA”), (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to compliance with conditions set forth in the SFA.
Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor,
shares, debentures and units of shares and debentures of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares pursuant to an offer made under Section 275 of the SFA except:
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to an institutional investor (for corporations, under Section 274 of the SFA) or to a relevant person defined in Section 275(2) of the SFA, or to any person pursuant to an offer that is made on terms that such shares, debentures and units of shares and debentures of that corporation or such rights and interest in that trust are acquired at a consideration of not less than S$200,000 (or its equivalent in a foreign currency) for each transaction, whether such amount is to be paid for in cash or by exchange of securities or other assets, and further for corporations, in accordance with the conditions specified in Section 275 of the SFA;

where no consideration is or will be given for the transfer; or

where the transfer is by operation of law.
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LEGAL MATTERS
The validity of the shares of common stock offered by this prospectus supplement will be passed upon for us by Ropes & Gray LLP, Boston, Massachusetts. The underwriters are being represented by Proskauer Rose LLP, New York, New York.
EXPERTS
The consolidated financial statements of Novavax, Inc., incorporated by reference in this prospectus supplement from Novavax, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2017, and the effectiveness of Novavax, Inc.’s internal control over financial reporting as of December 31, 2017 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.
WHERE YOU CAN FIND MORE INFORMATION
We have filed a registration statement on Form S-3 with the SEC registering the offer and sale of our common stock offered by this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus does not include all of the information contained in the registration statement. You should refer to the registration statement, its exhibits and the information incorporated in this prospectus supplement and the accompanying prospectus for additional information.
We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any materials that we file with the SEC at its Public Reference Room, 100 F Street, N.E., Washington, D.C. 20549. You may call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. Our SEC filings are also available to the public from the SEC’s website at http://www.sec.gov.
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC’s rules allow us to “incorporate by reference” information we have filed with the SEC, which means that we can disclose important information by referring you to those documents. The information incorporated by reference is a part of this prospectus supplement and the accompanying prospectus, and information that we file later with the SEC will automatically update and supersede the information included and/or incorporated by reference in this prospectus supplement. We incorporate by reference into this prospectus supplement, the accompanying prospectus, the documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (other than, in each case, any document or portion of a document that is deemed not to be filed) prior to the time that we sell all of the securities offered by this prospectus supplement or otherwise terminate this offering:

our Annual Report on Form 10-K for the year ended December 31, 2017, filed with the SEC on March 14, 2018;

our Definitive Proxy Statement on Schedule 14A, filed on April 28, 2017 (excluding those portions that are not incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2016);

our Current Reports on Form 8-K, filed with the SEC on January 9, 2018 and March 15, 2018 (with respect to Item 5.02 only); and

the description of our common stock contained in the Registration Statement on Form 10 filed with the SEC on September 14, 1995, including any amendments or reports filed for the purpose of updating such description.
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You may obtain documents incorporated by reference into this prospectus supplement and the accompanying prospectus at no cost by requesting them in writing or telephoning us at the following address:
Investor Relations
Novavax, Inc.
20 Firstfield Road,
Gaithersburg, Maryland, 20878
(240) 268-2000
ir@novavax.com
These filings are also made available, free of charge, on our website at www.novavax.com. The information contained in, and that can be accessed through, our website is not incorporated into and does not form a part of this prospectus supplement or the accompanying prospectus.
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PROSPECTUS
[MISSING IMAGE: http://api.tenkwizard.com/cgi/image?quest=1&rid=23&ipage=12182270&doc=2]
Novavax, Inc.
$200,000,000
Common Stock
Preferred Stock
Warrants
Units
We may issue and sell from time to time our common stock, preferred stock, warrants and/or units consisting of two or more of any such securities on terms to be determined at the time of sale. The preferred stock may be convertible into shares of our common stock, and the warrants may be exercisable for shares of our common stock or shares of our preferred stock. We may offer these securities separately or together in one or more offerings with a maximum aggregate offering price of  $200,000,000.
We will provide a prospectus supplement each time we issue securities, specifying the terms of the securities being sold as well as the terms of that offering.
You should read this prospectus and any prospectus supplement, including any information incorporated herein and therein by reference, carefully before you invest.
The securities may be sold directly by us, through dealers, agents or underwriters designated from time to time, or through any combination of these methods. If dealers, agents or underwriters are involved in a particular sale, we will disclose their names and the nature of our arrangements with them in the applicable prospectus supplement. The net proceeds we expect to receive from any sale also will be included in the applicable prospectus supplement.
Our common stock is traded on the Nasdaq Global Select Market, or Nasdaq, under the symbol “NVAX.” On December 21, 2017, the closing price of our common stock as reported on Nasdaq was $1.15 per share. None of the other securities offered under this prospectus are publicly traded.
Investing in these securities involves a high degree of risk. See “RISK FACTORS” on page 3.
This prospectus may not be used to offer or sell securities unless accompanied by a prospectus supplement for the securities being sold.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.
The date of this Prospectus is January 12, 2018.

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ABOUT THIS PROSPECTUS
This prospectus is part of a “shelf’ registration statement that we filed with the Securities and Exchange Commission (the “SEC” or “Commission”) on December 29, 2017. By using a shelf registration statement, we may, from time to time, issue and sell common stock, preferred stock, warrants and/or units consisting of our common stock, preferred stock and warrants in one or more offerings up to an aggregate maximum offering price of  $200,000,000 (or its equivalent in other currencies). Each time we sell any of our securities, we will provide a prospectus supplement that will contain more specific information about the offering and the terms of the securities being sold. We may also add, update or change in the prospectus supplement any of the information contained in this prospectus or the documents incorporated by reference.
This prospectus and the prospectus supplements provide you with a general description of the Company and our securities; for further information about our business and our securities, you should refer to the registration statement and the documents incorporated by reference, as described under the heading “Where You Can Find More Information.”
You should rely only on the information contained in this prospectus and in the applicable prospectus supplement (including in any documents incorporated by reference herein or therein). We have not authorized anyone to provide you with any different information. We are offering to sell our securities, and seeking offers to buy, only in jurisdictions where offers and sales are permitted. The information contained in this prospectus or in any prospectus supplement is accurate only as of the date of such document, and the information contained in any document incorporated herein or therein by reference is accurate only as of the date of such document incorporated by reference. Our business, financial condition, liquidity, results of operations, and prospects may have changed since those dates.
Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus to “the Company,” “Novavax,” “we,” “us” and “our” refer to Novavax, Inc.
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PROSPECTUS SUMMARY
The following is a summary of selected information contained elsewhere or incorporated by reference in this prospectus. It does not contain all of the information that you should consider before buying our securities. You should read this entire prospectus carefully, as well as any applicable prospectus supplement, the documents incorporated by reference into this prospectus, or the applicable prospectus supplement, and any free writing prospectus we have prepared, including the material referenced under the heading “Risk Factors”.
NOVAVAX
Novavax is a clinical-stage biotechnology company focused on the discovery, development and commercialization of recombinant nanoparticle vaccines and adjuvants. Using innovative proprietary recombinant nanoparticle vaccine platform technology, we produce vaccine candidates to efficiently and effectively respond to both known and emerging disease threats. Our vaccine candidates are genetically engineered three-dimensional nanostructures that incorporate recombinant proteins critical to disease pathogenesis. Our product pipeline targets a variety of infectious diseases, with clinical vaccine candidates for respiratory syncytial virus (RSV), influenza and Ebola virus (EBOV), and preclinical programs for other infectious disease vaccine candidates.
We are also developing immune stimulating saponin-based adjuvants through our wholly owned Swedish subsidiary, Novavax AB. Our lead adjuvant, Matrix-M™, has been shown to enhance immune responses and was well-tolerated in multiple clinical trials that we have conducted.
Novavax was incorporated in 1987 under the laws of the State of Delaware. Our principal executive offices are located at 20 Firstfield Road, Gaithersburg, Maryland, 20878. Our telephone number is (240) 268-2000 and our website address is www.novavax.com. The information contained in, and that can be accessed through, our website is not incorporated into and does not form a part of this prospectus.
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RISK FACTORS
Investing in our securities involves a high degree of risk. For a discussion of the cautionary information you should carefully consider before deciding to purchase any of our securities, please review the risk factors included in the documents incorporated by reference in this prospectus, including “Part I, Item 1A — Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2016, filed with the SEC on February 27, 2017, and “Part II, Item 1A - Risk Factors” in our most recent Quarterly Report on Form 10-Q for the period ended September 30, 2017, filed with the SEC on November 7, 2017, as well as any amendment or update to our risk factors reflected in subsequent filings with the SEC. The risks and uncertainties described in that section and in the other documents incorporated by reference are not the only risks and uncertainties we face. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business operations. If negative events occur, our business, financial condition, results of operations, and prospects would suffer. In that event, the market price of our securities could decline, and you may lose all or part of your investment.
USE OF PROCEEDS
The use of proceeds from the disposition of securities covered by this prospectus will be as set forth in the applicable prospectus supplements.
PLAN OF DISTRIBUTION
General
We may sell the securities being offered hereby from time to time in one or more of the following ways:

through one or more underwriters;

through dealers, who may act as agents or principal (including in a block trade in which a broker or dealer so engaged will attempt to sell the shares as agent but may position and resell a portion of the block as principal to facilitate the transaction);

directly to one or more counter-parties;

through agents;

through registered direct offerings;

as part of a collaboration with a third party;

as part of an acquisition or merger with a third party;

through at-the-market issuances;

in privately negotiated transactions; and

in any combination of these methods of sale.
We will set forth in a prospectus supplement the terms of the offering, including:

the name or names of any agents, underwriters or dealers;

the terms of the securities being offered, including the purchase price and the proceeds we will receive from the sale;

any underwriting discounts and commissions or agency fees and other items constituting underwriters’ or agents’ compensation;

any options under which underwriters may purchase additional securities from us; and

any discounts or concessions allowed or reallowed or paid to dealers.
The distribution of the securities may be effected from time to time in one or more transactions at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices related to the prevailing market prices, or at negotiated prices.
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Underwriters, dealers, and agents that participate in the distribution of the securities may be underwriters as defined in the Securities Act, and any discounts or commissions they receive from us and any profit on their resale of the securities may be treated as underwriting discounts and commissions under the Securities Act. We will identify in the applicable prospectus supplement any underwriters, dealers and agents and will describe their compensation. We may have agreements with underwriters, dealers and agents to indemnify them against specified civil liabilities, including liabilities under the Securities Act. Underwriters, dealers, and agents may engage in transactions with or perform services for us in the ordinary course of their businesses.
Underwriters
If underwriters are used in the sale, we will execute an underwriting agreement with those underwriters relating to the sale of the securities. Unless otherwise set forth in the applicable prospectus supplement, the obligations of the underwriters to purchase these securities will be subject to conditions, and the underwriters will be obligated to purchase all of the securities if any are purchased.
The securities subject to an underwriting agreement will be acquired by the underwriters for their own account and may be resold by them from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Underwriters may be deemed to have received compensation in the form of underwriting discounts or commissions and may also receive commissions from the purchasers of these securities for whom they may act as agent. Underwriters may sell these securities to or through dealers. These dealers may receive compensation in the form of discounts, concessions, or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent. Any public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.
Agents
We may designate agents who agree to solicit purchases for the period of their appointment or to sell securities on a continuing basis. Unless the prospectus supplement provides otherwise, agents will act on a best efforts basis for the period of their appointment. Agents may receive compensation in the form of commissions, discounts, or concessions from us. Agents may also receive compensation from the purchasers of the securities. Each particular agent will receive compensation from us in amounts negotiated in connection with the sale, which might be in excess of customary commissions.
Dealers
We may also sell securities to dealers acting as principals. If we sell our securities to a dealer as a principal, then the dealer may resell those securities to the public at varying prices to be determined by such dealer at the time of resale. The name of a dealer and the terms of the transactions will be set forth in the applicable prospectus supplement.
Direct Sales
We may also sell securities directly to one or more purchasers, in which case underwriters or agents would not be involved in the transaction.
Institutional Purchasers
Further, we may authorize agents, underwriters, or dealers to solicit offers by certain types of purchasers to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in an applicable prospectus supplement.
Indemnification
We may indemnify underwriters, dealers, or agents who participate in the distribution of securities against certain liabilities, including liabilities under the Securities Act, and agree to contribute to payments which these underwriters, dealers, or agents may be required to make.
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DESCRIPTION OF OUR CAPITAL STOCK
Set forth below is a summary of the material terms of our capital stock. This summary is not complete. We encourage you to read our Second Amended and Restated Certificate of Incorporation, as amended through June 18, 2015, and our Amended and Restated By-Laws, both of which are included as exhibits to the registration statement of which this prospectus is a part.
General
Our authorized capital stock consists of: (1) 600,000,000 shares of common stock, par value $0.01 per share, of which 323,229,390 shares were outstanding as of December 21, 2017, and (2) 2,000,000 shares of preferred stock, par value $0.01 per share, none of which were outstanding on December 21, 2017.
Common Stock
Holders of common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders and do not have cumulative voting rights.
Holders of our common stock are entitled to receive ratably such dividends, if any, as may be declared by the board of directors out of funds legally available therefor, subject to any preferential dividend rights of any outstanding preferred stock. Upon the liquidation, dissolution, or winding up of the Company, the holders of our common stock are entitled to receive ratably the net assets of the Company available after the payment of all debts and liabilities and subject to the prior rights of any outstanding preferred stock.
Holders of our common stock are not entitled to pre-emptive rights or any rights of conversion. Outstanding shares of our common stock are, and the shares covered by this prospectus would be expected to be, when issued, fully paid and nonassessable. The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of holders of shares of any series of preferred stock which we may designate and issue in the future.
Our common stock is traded on the Nasdaq Global Select Market under the symbol “NVAX.” On December 21, 2017, the closing price of our common stock as reported on the Nasdaq Global Select Market was $1.15 per share.
The registrar and transfer agent for our common stock is Computershare Limited, 250 Royall Street, Canton, MA 02021.
Preferred Stock
The board of directors may, without further action by the stockholders, issue preferred stock in one or more series and fix the rights and preferences thereof. Our Second Amended and Restated Certificate of Incorporation grants the board of directors authority to issue preferred stock and to determine its rights and preferences without the need for further stockholder approval.
Examples of rights and preferences the board of directors may fix include dividend rates, conversion rights, voting rights, pre-emptive rights, terms of redemption (including sinking fund provisions), redemption prices, and liquidation preferences. The issuance of preferred stock, while providing desirable flexibility in connection with possible financings, could have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from acquiring, a majority of our outstanding voting stock.
The terms of any particular series of preferred stock will be described in the prospectus supplement relating to the offering of shares of that particular series of preferred stock and may include, among other things:

the title and stated value;

the number of shares authorized;

the liquidation preference per share;

the purchase price;
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the dividend rate, period and payment date, and method of calculation (including whether cumulative or non-cumulative), if any;

terms and amount of any sinking fund, if applicable;

provisions for redemption or repurchase, if applicable, and any restrictions on the ability of the Company to exercise such redemption and repurchase rights;

conversion rights and rates, if applicable, including the conversion price and how and when it will be calculated and adjusted;

voting rights, if any;

preemptive rights, if any;

restrictions on sale, transfer, and assignment, if any;

the relative ranking and preferences of the preferred stock; and

any other specific terms, rights or limitations of, or restrictions on, such preferred stock.
Provisions of our Second Amended and Restated Certificate of Incorporation, Amended and Restated By-laws, and Delaware Law
Certain provisions of our Second Amended and Restated Certificate of Incorporation and Amended and Restated By-Laws may be deemed to have an anti-takeover effect and may prevent, delay, or defer a tender offer or takeover attempt that a stockholder may deem in his, her, or its best interest. The existence of these provisions also could limit the price that investors might be willing to pay for our securities. Such provisions include:
Staggered Board, Removal of Directors, and Charter Amendments relating to the Board
Our Second Amended and Restated Certificate of Incorporation and Amended and Restated By-Laws provide for the division of our board of directors into three classes, with no one class having more than one more director than any other class, serving staggered three year terms. Our Second Amended and Restated Certificate of Incorporation provides that any amendments to the charter relating to the number, classes, election, term, removal, vacancies, and related provisions with respect to the board of directors may only be made by the affirmative vote of the holders of at least 75% of the shares of capital stock issued and outstanding and entitled to vote. These provisions may have the effect of making it more difficult for a third party to acquire control of the Company, or of discouraging a third party from attempting to acquire control of the Company.
Authorized but Unissued Shares
The authorized but unissued shares of our common stock and preferred stock are available for future issuance without stockholder approval, subject to any limitations imposed by the NASDAQ Stock Market. These additional shares may be utilized for a variety of corporate purposes. In particular, our board of directors could issue shares of preferred stock that could, depending on the terms of the series, impede the completion of a takeover effort. Our board of directors may determine that the issuance of such shares of preferred stock is in the best interest of the Company and our stockholders. Such issuance could discourage a potential acquiror from making an unsolicited acquisition attempt through which such acquiror may be able to change the composition of the board, including a tender offer or other transaction a majority of our stockholders might believe to be in their best interest or in which stockholders might receive a substantial premium for their stock over the then-current market price.
Advance Notice Requirements for Stockholder Proposals and Director Nominations
Our Amended and Restated By-Laws provide that a stockholder seeking to bring business before an annual meeting of stockholders, or to nominate candidates for election as directors, must provide timely notice of such stockholder’s intention in writing. To be timely, a stockholder nominating individuals for election to the Board of Directors or proposing business must provide advanced notice to the Company not
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less than 60 days nor more than 90 days prior to the anniversary date of the prior year’s annual meeting of stockholders or, in the case of any special meeting, not less than 60 days nor more than 90 days prior to the special meeting, unless, in the case of annual meeting, such meeting occurs more than 30 days before or after such anniversary date, or, in the case of a special meeting, such meeting occurs less than 100 days after notice or public disclosure of the date of the special meeting is given or made, in which cases notice will be timely if received not later than the close of business on the tenth day after the day on which notice or public announcement of the date of such meeting was made.
Limits on Ability of Stockholders to Act by Written Consent
Our Second Amended and Restated Certificate of Incorporation provides that our stockholders may not act by written consent. In addition, our Second Amended and Restated Certificate of Incorporation requires that special meetings of stockholders be called only by our board of directors, our chief executive officer, or our president if there is no chief executive officer. Further, business transacted at any special meeting of stockholders is limited to matters relating to the purpose or purposes stated in the notice of meeting. This limit on the ability of our stockholders to act by written consent or to call a special meeting may lengthen the amount of time required to take stockholder proposed actions.
Section 203 of the General Corporation Law of the State of Delaware
We are subject to Section 203 of the Delaware General Corporation Law. This statute regulating corporate takeovers prohibits a Delaware corporation from engaging in any business combination with an interested stockholder for three years following the date that the stockholder became an interested stockholder, unless:

prior to the date of the transaction, the board of directors of the corporation approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

upon completion of the transaction that resulted in the interested stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the number of shares outstanding (1) shares owned by persons who are directors and also officers, and (2) shares owned by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 23% of the outstanding voting stock that is not owned by the interested stockholder.
Generally, a business combination includes a merger, asset or stock sale, or other transaction resulting in a financial benefit to the interested stockholder. An interested stockholder is any person who, together with such person’s affiliates and associates (1) owns 15% or more of a corporation’s voting securities or (2) is an affiliate or associate of a corporation and was the owner of 15% or more of the corporation’s voting securities at any time within the three year period immediately preceding a business combination governed by Section 203. We expect the existence of this provision to have an anti-takeover effect with respect to transactions our board of directors does not approve.
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DESCRIPTION OF WARRANTS
This description only summarizes the terms of warrants that we may offer under this prospectus and related warrant agreements and certificates. You should refer to the warrant agreement, including the form of warrant certificate representing the warrants, relating to the specific warrants being offered for complete terms, which would be provided at the time of such offering. Such warrant agreement, together with the warrant certificate, would be filed with the SEC in connection with the offering of the specific warrants.
We may issue warrants for the purchase of common or preferred stock. Warrants may be issued independently or together with common or preferred stock, and may be attached to or separate from any offered securities.
We may evidence a series of warrants by warrant certificates that we issue under a separate warrant agreement. We may enter into a warrant agreement with a warrant agent and, if so, we will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to the particular series of warrants.
The particular terms of any series of warrants will be described in the prospectus supplement relating to the series. Those terms may include:

the title of such warrants;

the aggregate number of such warrants;

the price or prices at which such warrants will be issued;

the currency or currencies (including composite currencies) in which the price of such warrants may be payable;

the terms of the securities issuable upon exercise of such warrants and the procedures and conditions relating to the exercise of such warrants;

the price at which the securities issuable upon exercise of such warrants may be acquired;

the dates on which the right to exercise such warrants will commence and expire;

any provisions for adjustment of the number or amount of securities receivable upon exercise of the warrants or the exercise price of the warrants;

if applicable, the minimum or maximum amount of such warrants that may be exercised at any one time;

if applicable, the designation and terms of the securities with which such warrants are issued and the number of such warrants issued with each such security or principal amount of such security;

if applicable, the date on and after which such warrants and the related securities will be separately transferable;

information with respect to book-entry procedures, if any; and

any other terms of such warrants, including terms, procedures and limitations relating to the exchange or exercise of such warrants.
Each warrant will entitle its holder to purchase the number of shares of common or preferred stock at the exercise price set forth in, or calculable as set forth in, the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the expiration date set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void. We will specify the place or places where, and the manner in which, warrants may be exercised in the applicable prospectus supplement. We will set forth on the reverse side of the applicable certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver upon exercise.
Prior to the exercise of any warrants to purchase preferred stock or common stock, holders of the warrants will not have any of the rights of holders of the preferred stock or common stock purchasable upon exercise, including the right to vote or to receive any payments of dividends.
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DESCRIPTION OF OUR UNITS
We may issue units comprised of two or more of the other securities described in this prospectus in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The units may be issued under unit agreements to be entered into between us and a bank or trust company, as unit agent, as detailed in the prospectus supplement relating to units being offered. The prospectus supplement will describe:

the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances the securities comprising the units may be held or transferred separately;

a description of the terms of any unit agreement governing the units;

a description of the provisions for the payment, settlement, transfer, or exchange of the units; and

whether the units will be issued in fully registered or global form.
DIVIDEND POLICY
We have never paid cash dividends on our common stock. We currently anticipate that we will retain any earnings for use in the development of our business and do not anticipate paying any cash dividends in the foreseeable future.
LEGAL MATTERS
Unless the applicable prospectus supplement indicates otherwise, our counsel Ropes & Gray LLP, Boston Massachusetts, will pass upon the validity of the securities offered by this prospectus.
EXPERTS
The consolidated financial statements of Novavax, Inc. appearing in Novavax Inc.’s Annual Report (Form 10-K) for the year ended December 31, 2016, and the effectiveness of Novavax Inc.’s internal control over financial reporting as of December 31, 2016 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.
WHERE YOU CAN FIND MORE INFORMATION
We have filed a registration statement on Form S-3 with the SEC registering the offer and sale of our securities offered by this prospectus. This prospectus does not include all of the information contained in the registration statement. You should refer to the registration statement, its exhibits, and the information incorporated in this prospectus for additional information.
We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any materials that we file with the SEC at its Public Reference Room, 100 F Street, N.E., Washington, D.C. 20549. You may call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. Our SEC filings are also available to the public from the SEC’s website at http://www.sec.gov.
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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE
The SEC’s rules allow us to “incorporate by reference” information we have filed with the SEC, which means that we can disclose important information by referring you to those documents. The information incorporated by reference is a part of this prospectus, and information that we file later with the SEC will automatically update and supersede the information included and/or incorporated by reference in this prospectus. We incorporate by reference into this prospectus the documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (other than, in each case, any document or portion of a document that is deemed not to be filed) after the initial filing of the registration statement that contains this prospectus and prior to the time that we sell all of the securities offered by this prospectus:

our Annual Report on Form 10-K for the year ended December 31, 2016, filed with the SEC on February 27, 2017;

our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2017, filed with the SEC on May 8, 2017, June 30, 2017, filed with the SEC on August 8, 2017 and September 30, 2017, filed with the SEC on November 7, 2017;

our Current Reports on Form 8-K, filed with the SEC on June 16, 2017, July 26, 2017, October 13, 2017, November 7, 2017 and December 29, 2017; and

the description of our common stock contained in the Registration Statement on Form 10 filed with the SEC on September 14, 1995, including any amendments or reports filed for the purpose of updating such description.
You may obtain documents incorporated by reference into this prospectus at no cost by requesting them in writing or telephoning us at the following address:
Investor Relations
Novavax, Inc.
20 Firstfield Road
Gaithersburg, MD 20878
(240) 268-2000
ir@novavax.com
These filings are also made available, free of charge, on our website at www.novavax.com. The information contained in, and that can be accessed through, our website is not incorporated into and does not form a part of this prospectus.
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           Shares
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Novavax, Inc.
Common Stock
P R O S P E C T U S   S U P P L E M E N T
Joint Book-Running Managers
Citigroup
Piper Jaffray​
The date of this Prospectus Supplement is            , 2018