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.

Filed pursuant to Rule 424(b)(5)
Registration No. 333-193549

Subject to Completion Dated March 24, 2015

PRELIMINARY PROSPECTUS SUPPLEMENT
(to Prospectus dated January 24, 2014)

$175,000,000

Novavax, Inc.

Common Stock

 

We are offering up to $175,000,000 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 March 23, 2015, as reported by The NASDAQ Global Select Market, was $9.55 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-7 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 $26,250,000 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            , 2015.

 

Joint Book-Running Managers

J.P. Morgan	Citigroup

 

The date of this Prospectus Supplement is              , 2015

TABLE OF CONTENTS

Prospectus Supplement

ABOUT THIS PROSPECTUS SUPPLEMENT		S-1
PROSPECTUS SUMMARY		S-2
NOTE REGARDING FORWARD-LOOKING STATEMENTS		S-6
RISK FACTORS		S-7
USE OF PROCEEDS		S-27
DILUTION		S-28
MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR NON-U.S. HOLDERS OF COMMON STOCK		S-29
UNDERWRITING		S-33
LEGAL MATTERS		S-39
EXPERTS		S-39
WHERE YOU CAN FIND MORE INFORMATION		S-39
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		S-40
Prospectus
ABOUT THIS PROSPECTUS		2
PROSPECTUS SUMMARY		2
NOVAVAX		2
RISK FACTORS		3
USE OF PROCEEDS		3
PLAN OF DISTRIBUTION		3
DESCRIPTION OF OUR CAPITAL STOCK		5
DESCRIPTION OF WARRANTS		8
DESCRIPTION OF OUR UNITS		9
DIVIDEND POLICY		9
LEGAL MATTERS		10
EXPERTS		10
WHERE YOU CAN FIND MORE INFORMATION		10
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		11

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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 biopharmaceutical company focused on developing recombinant protein nanoparticle vaccines and adjuvants.

Using innovative proprietary recombinant protein nanoparticle vaccine technology, Novavax produces vaccine candidates to efficiently and effectively respond to both known and newly emerging diseases. The Company’s product pipeline includes a respiratory syncytial (RSV) virus F-protein nanoparticle vaccine candidate (RSV F). RSV is a widespread disease that causes infections of the lower respiratory tract. While RSV affects persons of all ages, it acutely impacts infants, the elderly, young children and individuals with compromised immune systems. We are developing RSV F vaccine candidates for the benefit of three susceptible target populations: the elderly, infants (receiving protection through antibodies transferred from their mothers who would be immunized during the last trimester of pregnancy) and pediatrics, and are in clinical stage trials in each of these three programs.

• In October 2014, we initiated enrollment in a Phase 2 dose-confirmation clinical trial of our RSV F vaccine candidate in 1,600 older adults (>60 years of age). Recruitment was completed in November, and the preliminary data from this trial are expected in the third quarter of 2015. We believe these data will inform the next steps in the development of our RSV elderly program. In May 2014, we released one-year follow-up data from the Phase 1 clinical trial initiated in October 2012. Those data demonstrate that for the group receiving the 90μg antigen dose without adjuvant, anti-F levels and palivizumab competing antibodies were significantly elevated over baseline at day 180, with neutralizing antibody levels that were considered protective for both the RSV A and RSV B strains. We believe these findings support the development of an annual RSV F vaccine candidate dose that can provide protection over the four to five month period of a typical RSV season.

• In September 2014, we initiated a Phase 2 clinical trial of our RSV F vaccine candidate in healthy women in their third trimester of pregnancy. This trial, which enrolled fifty (50) pregnant women, is evaluating the safety and immunogenicity of our RSV F vaccine candidate in pregnant women and will assess the impact of maternal immunization on RSV-specific antibody levels through the baby’s first six months of life and infant safety through the first year of life. The preliminary data from this trial are expected in the third quarter of 2015 and will inform the next steps in the development of our RSV maternal program. In November 2014, we announced that the U.S. Food and Drug Administration, Center for Biologics Evaluation and Research (FDA) had granted Fast Track Designation to our RSV F vaccine candidate for protection of infants via maternal immunization. The program is intended to facilitate development and expedite review of drugs to treat serious and life-threatening conditions so that an approved product can reach the market expeditiously.

• In November 2014, we initiated a Phase 1 clinical trial of our RSV F vaccine candidate in 150 healthy pediatric subjects two to six years of age designed to evaluate the safety and immunogenicity of our RSV F Vaccine in children. Although still active, we have currently delayed enrollment on this trial during RSV season, and are considering how best to reinitiate enrollment. We currently expect data from this at the end of 2015 or early 2016 depending on what we do to reinitiate enrollment.

We expect a significant increase in research and development expenses over prior years primarily due to additional RSV F vaccine candidate clinical trials in the primary indications of elderly immunization, maternal

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immunization and pediatric immunization, as well as higher employee-related and facility costs to support product development of our RSV F vaccine candidate and other potential vaccine candidates.

The U.S. Department of Health and Human Services, Biomedical Advanced Research and Development Authority (HHS BARDA) awarded us a contract in 2011, which funds the development of both our multivalent seasonal influenza and pandemic influenza VLP vaccine candidates. Our contract with HHS BARDA is a cost-plus-fixed-fee contract, which reimburses us for allowable direct contract costs incurred plus allowable indirect costs and a fixed-fee earned in the ongoing clinical development and product scale-up of our multivalent seasonal and monovalent pandemic influenza vaccines. In September 2014, we announced that HHS BARDA had exercised and initiated a two-year option to our contract, which not only extended the contract until September 2016, but also added scope to support our development activities leading up to planned Phase 3 clinical studies and $70 million of funding on top of the remainder of the $97 million base period funding. During 2014, we recognized revenue of $26.0 million and have recognized approximately $78 million in revenue since the inception of the contract.In November 2014, under our contract with HHS BARDA, we initiated a Phase 2 clinical trial of our quadrivalent seasonal influenza virus-like particles (VLP) vaccine candidate in 400 healthy adults. The primary outcomes of the trial will assess safety and tolerability of the seasonal influenza VLP vaccine candidate and quantify immune responses to each of the four influenza strains based on hemagglutination-inhibiting antibody titers. In addition, secondary outcomes will evaluate neuraminidase-inhibition antibody titers for all four influenza strains. The preliminary data from this trial are expected in the second quarter of 2015 and will inform the next steps in the development of our quadrivalent seasonal influenza VLP vaccine candidate. Data from our previous Phase 2 clinical trial, announced in July 2012, showed that our quadrivalent seasonal influenza VLP vaccine candidate demonstrated immunogenicity against all four viral strains based on hemagglutination inhibition responses at day 21, was well-tolerated, and met the FDA accelerated approval seroprotection rates criterion for all four viral strains, although the potential to fulfill the seroconversion rates criterion was demonstrated in just three of the four viral strains. Following that Phase 2 clinical trial, we focused our activities on manufacturing processes that will better ensure consistent, enhanced immune responses for all four strains.

In collaboration with HHS BARDA, we have now developed and delivered compelling safety and immunogenicity data on two pandemic vaccine candidates, H5N1 and H7N9, which provide the U.S. government with alternatives for dealing with future potential threats. In September 2014, we announced positive results from a Phase 1/2 clinical trial of our pandemic H7N9 influenza VLP vaccine candidate adjuvanted with Matrix-M^TM in 610 healthy adults. Under our contract with HHS BARDA, the Phase 1/2 clinical trial was designed as a dose-ranging, randomized, observer-blinded, placebo-controlled clinical trial, to determine the contribution of Matrix-M to potential antigen dose sparing regimens. Our pandemic H7N9 influenza VLP vaccine candidate, with and without Matrix-M, was well tolerated and demonstrated a safety profile similar to the company’s prior experience with another saponin-based adjuvant. Matrix-M adjuvanted formulations demonstrated immunogenicity and dose-sparing benefits relative to unadjuvanted antigen. Hemagglutination-inhibiting antibody titers were generally comparable to those reported in prior studies with another saponin adjuvant and the vaccine also elicited significant anti-neuraminidase antibodies. In October 2014, we announced that the FDA had granted Fast Track Designation to our pandemic H7N9 influenza VLP vaccine candidate with Matrix-M.

We are also developing an Ebola virus (EBOV) glycoprotein (GP) vaccine candidate, which was modeled using the 2014 Makona strain, and has been successfully tested in rodent, rabbit, and non-human primate pre-clinical models. We have also tested the vaccine with our Matrix-M adjuvant, which appears to significantly contribute to enhanced immunogenicity and dose-sparing. We initiated production under good manufacturing practices (GMP) of our EBOV GP vaccine in the fourth quarter of 2014 and in February 2015, we announced the initiation of enrollment in a Phase 1 clinical trial of our EBOV GP vaccine candidate in 150 healthy adults to evaluate the safety and immunogenicity of this vaccine candidate in ascending doses, with and without our Matrix-M adjuvant. We expect preliminary data from this trial to be available in mid-2015. In addition, we announced successful preliminary data from a non-human primate challenge study of our EBOV GP vaccine candidate in which the challenge was lethal for the control animal, whereas 100% of the immunized animals were protected. Plans for the subsequent clinical trial(s) will be developed based on the results of our Phase 1 clinical trial and in collaboration with global regulatory authorities and world health agencies.

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Novavax is involved in several international partnerships, including collaborations with Cadila Pharmaceuticals of India, LG Life Sciences of Korea, and PATH Vaccine Solutions (PATH). Together, Novavax’ network supports its global commercialization strategy to create real and lasting change in the biopharmaceutical and vaccinology fields.

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 option to purchase additional shares).

Use of proceeds

We intend to use the net proceeds from this offering for the advancement of our lead vaccine candidates, including the preparation and potential initiation of Phase 3 clinical trials of our elderly RSV and maternal RSV programs, as well as our other clinical and pre-clinical research programs and general corporate purposes, including working capital, product development, manufacturing and process development expenditures and capital expenditures, as well as acquisitions and other strategic purposes. Pending the application of the net proceeds, we expect to invest the proceeds in investment-grade, interest-bearing instruments or other securities. 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-7 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 240,086,404 shares of our common stock outstanding as of March 19, 2015.

The number of shares of our common stock to be outstanding after this offering excludes the following, each as of March 19, 2015:

• 16,375,372 shares of our common stock reserved for issuance upon the exercise of outstanding stock options at a weighted average exercise price of $3.27 per share;

• 1,313,388 shares of our common stock reserved for issuance under our Employee Stock Purchase Plan; and

• 6,954,538 shares of our common stock issuable upon the exercise of outstanding stock options under our 2015 stock plan (which remains subject to the adoption by our stockholders at our 2015 annual meeting), at a weighted average exercise price of $8.94 per share.

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, the efficacy, safety and intended utilization of our product candidates, the development of our clinical stage product candidates and our recombinant vaccine technologies, the future development of our product candidates by us, the conduct, timing and results of future clinical trials, plans regarding regulatory filings, our available cash resources and the availability of financing generally, our plans regarding partnering activities and business development initiatives, 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, 2014, filed with the SEC on February 27, 2015, 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, 2014 was $493.1 million. Our revenue for the last three fiscal years was $30.7 million in 2014, $20.9 million in 2013, and $22.1 million in 2012. Prior to 2011, we recorded limited revenue from research contracts, licenses and agreements to provide vaccine candidates, services and technologies. We cannot be certain that we will be successful in entering into strategic alliances or collaborative arrangements with other companies and government agencies that will result in significant revenue to offset our expenses. Our net losses for the last three fiscal years were $82.9 million in 2014, $52.0 million in 2013, and $28.5 million in 2012.

Our recent historical losses have predominantly resulted 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. We believe our expenses will continue to increase, as a result of higher research and development efforts to support the development of our vaccine candidates.

Although certain specified costs associated with the development of our influenza vaccines may be reimbursed under our contract with HHS BARDA, and to a more limited extent, certain outside costs associated with the development of our RSV maternal vaccine may be reimbursed under our contract with PATH, nevertheless we expect to continue to incur significant operating expenses and anticipate that our losses will increase in the foreseeable future as we seek to:

• conduct clinical trials for RSV, Ebola and an RSV-influenza combination respiratory vaccine candidate;

• conduct pre-clinical studies for other early-stage vaccine candidates;

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

• 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 cannot predict when, if ever, we might achieve profitability and cannot be certain that we will be able to sustain profitability, if achieved.

We have limited financial resources and we are not certain that we will 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 an amount sufficient to fully fund our operations for the foreseeable future, and we will therefore use our cash resources and expect to require additional funds to maintain our operations,

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continue our research and development programs, commence future pre-clinical studies and 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-profits and governmental entities, there are no assurances that we would be successful. We cannot be certain that adequate additional funding will 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, biopharmaceutical 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, this could affect our ability to execute our business plan as scheduled. Moreover, we rely and intend to rely on third-parties, including our clinical research organizations and certain other important vendors and consultants. As a result of the global economic situation, there may be 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 the HHS BARDA contract award and the exercise of the contract option period, we may not be able to fully fund our influenza programs.

The HHS BARDA contract is a cost-plus-fixed-fee contract that only reimburses certain specified activities that have been previously authorized by HHS BARDA. There is no guarantee that additional activities will not be needed and, if so, that HHS BARDA will reimburse us for these activities. Additionally, there are significant requirements associated with operating as a federal government contractor, which includes having appropriate accounting, project tracking and earned-value management systems implemented and operational, and we may not be able to consistently meet these requirements. Performance under the HHS BARDA contract requires that we comply with appropriate regulations and operational mandates, which require us to engage internal and external expertise for compliance. Our ability to be regularly and fully reimbursed for our activities will depend on our ability to comply and demonstrate compliance with such requirements.

The HHS BARDA contract award does not guarantee that we will be successful in future clinical trials, that the vaccine candidates will be licensed by the FDA, or that the contract award will continue to be available throughout the contract period.

The HHS BARDA contract provides a cost-plus-fixed-fee reimbursement opportunity for certain specified clinical and development activities, but we remain fully responsible for conducting these approved activities. The award of the HHS BARDA contract does not guarantee that any of these activities will be successful. Our

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inability to be successful with certain key clinical or development activities could jeopardize our ability to obtain FDA licensure to sell our vaccines.

HHS BARDA could decide to potentially delay certain of our activities, and we may elect to move forward with certain activities at our own risk and without HHS BARDA reimbursement.

Under the HHS BARDA contract, HHS BARDA regularly reviews our development efforts and clinical activities. Under certain circumstances, HHS BARDA may advise us to delay certain activities and invest additional time and resources before proceeding. If we follow such HHS BARDA advice, overall program delays and costs associated with additional resources for which we had not planned may result. Also, the costs associated with following such advice may or may not be reimbursed by HHS BARDA under our contract. Finally, we may decide not to follow the advice provided by HHS BARDA and instead pursue activities that we believe are in the best interest of the program and of the Company, even if HHS BARDA would not reimburse us under our contract.

HHS BARDA may decide not to extend our contract beyond the recently exercised option period.

The HHS BARDA contract has recently been extended by an additional two years through the option period for a total performance period of approximately five and a half years. Depending on how we perform during the option period, HHS BARDA may decide whether or not to extend the contract to include additional periods of time to complete the contract deliverables. For example, the HHS BARDA contract anticipates that we file Biologics License Applications (BLA) for licensure of both our seasonal influenza vaccine and our pandemic influenza vaccine; however, there is no guarantee that we will successfully complete all of the tasks required to file BLAs during this period. Although we believe that, based on our progress to date and the activities that we have planned in the future, HHS BARDA will want to extend the contract, there can be no guarantee that HHS BARDA will decide to extend our contract beyond September 2016.

Because of changes to the influenza vaccine industry and regulatory environment, accelerated approval by the FDA of our seasonal influenza vaccine candidate may not be available.

FDA regulations allow for the accelerated approval of a seasonal influenza vaccine based on a surrogate endpoint (i.e., HAI data) when there is a shortage of vaccine because influenza is a serious and sometimes, life-threatening disease. This may allow developers to obtain licensure well ahead of the timeline for demonstrating clinical efficacy, which is necessary for traditional approval. Because the seasonal influenza vaccine industry has made significant steps to provide sufficient supply to the recommended population in the U.S, the FDA may no longer view the development of our seasonal influenza vaccine as meeting an unmet medical need.

Our expectation that our pandemic influenza vaccine candidate will be granted accelerated approval by the FDA is not guaranteed.

As is the case with seasonal influenza, the FDA has articulated the immunogenicity criteria for accelerated approval of vaccines that address potential pandemic influenza strains. Because a controlled efficacy clinical trial of a pandemic vaccine candidate is not logistically or ethically possible, accelerated approval will require evidence that a seasonal vaccine made by the same manufacturing process as the pandemic vaccine is efficacious. There is no guarantee the FDA will grant accelerated approval of our pandemic vaccine before we provide seasonal influenza efficacy data. Also, because we currently anticipate that our seasonal influenza vaccine would not get accelerated approval from the FDA, it is likely that we would need to conduct larger and more expensive efficacy clinical trials and that licensure of our seasonal vaccine will be materially delayed for a year or more, assuming such licensure occurs at all, which may, in turn, delay the FDA approval of our pandemic vaccine.

Our wholly-owned subsidiary Novavax AB, collaborations with regional partners, such as Cadila, LGLS, and PATH, as well as contracts with international providers, expose us to additional risks associated with doing business outside the U.S., and any adverse event could have a material negative impact on our operations.

Swedish-based Novavax AB is a wholly-owned subsidiary of Novavax, Inc. We have also formed a joint venture with Cadila in India, entered into a license agreement with LGLS in South Korea, a clinical

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development agreement with PATH 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 other parts of the world. Risks of conducting business outside the U.S. include:

• multiple regulatory requirements could affect our ability to develop, manufacture and sell products in such local markets;

• compliance with anti-bribery laws such as the United States Foreign Corrupt Practices Act and similar anti-bribery laws in other jurisdictions;

• trade protections measures 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;

• potentially negative consequences from changes in or 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; 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, LGLS, and PATH are examples of these regional relationships. These relationships are likely to involve the licensing of our technology to our partner or entering into a distribution agreement, frequently on an exclusive basis. Generally, these 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 biopharmaceutical 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 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, pre-clinical 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 pre-clinical or early clinical trials may not translate into success in large-scale clinical trials. Further, success in clinical trials will likely lead to increased investment, accelerating cumulative losses to bring such products to market. 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

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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 our products.

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, LLC (a subsidiary of AstraZeneca PLC), 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.

There are many seasonal influenza vaccines 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 must 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, each of which is intended to be more efficacious than products currently being marketed. Our 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 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

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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.

We believe that there are at least two EBOV vaccine candidates that are currently being tested in humans: one by GlaxoSmithKline in collaboration with the United States 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. 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, continued development activities are likely to continue and potentially increase.

Regardless of the disease, smaller or early-stage companies and research institutions may also 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 subject 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. There is no assurance that we will 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. We have had turnover situations in key executive positions and the lack of management continuity and resulting lack of long-term history with our Company along with the learning curve that executives experience when they join our management team could result in operational and administrative inefficiencies and added costs. If we were to experience additional turnover at the executive level, these risks could be exacerbated.

We may not be able to attract qualified individuals for other key management or other personnel 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 required for the expansion of our activities, 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 have a material adverse effect on our business, financial condition and results of operations.

We may have product liability exposure.

The administration of drugs or vaccines to humans, whether in clinical trials or after marketing clearances are obtained, 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

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prior to FDA approval. Coverage is relatively expensive, and the market pricing can significantly fluctuate. Therefore, we may not be able to maintain insurance at a reasonable cost. There can be no assurance that we will 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 resulting from product liability 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 entities. 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, there is no guarantee that we will 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, including this offering, 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

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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.

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.

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;

• 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 pre-clinical 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 pre-clinical laboratory or animal studies.

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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 pre-clinical 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.

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.

Influenza vaccines are seasonal in nature. If a vaccine is not available early enough in the influenza season, we would likely have difficulty selling the vaccine. Further, pandemic outbreaks present only short-term opportunities for us. There is no way to predict when there will be a pandemic outbreak, the strain of the influenza or how long the pandemic will last. For these reasons, any delay in the delivery of an influenza vaccine could result in lower sales volumes, lower sale prices, or no sales. Because the strain of the seasonal

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influenza changes annually, inventory of seasonal vaccine cannot be sold during a subsequent influenza season. Any delay in the manufacture of our influenza 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.

Our manufacturing facilities may not be “Phase 3 ready” during 2015, which may impede or delay our ability to manufacture one or more vaccine candidates for subsequent clinical trials or obtain BLA for such vaccines.

Our manufacturing facility in Gaithersburg, Maryland, which is designed to manufacture Phase 3 vaccine candidates, has completed refurbishment and relocation of equipment from our Belward facility, as well as installation of new equipment, and although validation to begin manufacturing has been largely completed, additional equipment and validation work is ongoing, and there are risks associated with bringing the facility to “Phase 3 readiness.” These risks include but are not limited to contractor issues and delays, licensing and permitting delays or rejections, limitations and delays on the installation of new or custom-ordered equipment, issues associated with validating equipment, processes or other aspects of ensuring GMP manufacturing. There are many aspects of the project that rely on third party contractors and subcontractors, and delays are frequently encountered.

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 Novavax. 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 pre-clinical 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.

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Our collaborations may not be profitable.

We have formed CPLB with Cadila in India and, in connection with it, entered into a master services agreement pursuant to which we may request certain services from Cadila in the areas of biologics research, pre-clinical development, clinical development, process development, manufacturing scale-up and general manufacturing related services in India. We and Cadila amended the master services agreement first in July 2011, and subsequently in March 2013, March 2014 and February 2015, in each case to extend the term by one year for which services can be provided by Cadila under this agreement. Under the revised terms, if, by March 2016, the amount of services provided by Cadila under the master services agreement is less than $7.5 million, we will pay Cadila the portion of the shortfall amount that is less than or equal to $2.0 million and 50% of the portion of the shortfall amount that exceeds $2.0 million. We and Cadila also agreed to an amendment that allows CPLB, as of the beginning of 2013, to provide services on behalf of Cadila. Through December 31, 2014, we have purchased $5.7 million in services from Cadila pursuant to this agreement, including amounts in which CPLB provided the services on behalf of Cadila.

We have entered into a license agreement with LGLS that allows them to use our manufacturing and production technology to develop and sell our influenza vaccines. We have also entered into a clinical development agreement with PATH related to our RSV vaccine for maternal immunization in low-resource countries. To the extent PATH continues to fund 50% of the Company’s external clinical development costs, but the Company does not continue development, the Company would grant PATH a fully-paid license to its RSV F vaccine technology for use in pregnant women in such low-resource countries at terms that may not be favorable to the Company.

We cannot predict when, if at all, these relationships will lead to 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 cannot be certain that we will 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 based on immunogenicity;

• 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.

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In particular, there are significant challenges to market acceptance for seasonal influenza vaccines. For our seasonal vaccine to be accepted in the market, we 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 vaccine will be more efficacious than other 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 would be materially and adversely affected.

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

Because an important component of our adjuvant technology is extracted from a species of soap-bark tree (Quillaja saponaria) grown in Chile, we need long term access to quillaja extract with a consistent and sufficiently high quality. We need a secure supply of raw material, as well as back-up suppliers, or our adjuvant of 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, managed care programs 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 pre-clinical 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 subject or patient enrollment and retention, which is a function of many factors, including the size of the subject or patient population, the proximity of subjects and patients 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 pre-clinical 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

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• 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 pre-clinical 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 pre-clinical studies or clinical trials of similar products or that the results obtained in later phases of clinical trials may be inconsistent with those obtained in earlier phases. A number of companies in the biopharmaceutical 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 subjects or patients 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, LGLS in South Korea and PATH. 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, for example 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

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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 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 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 coverage and reimbursement for such products from third-party payers such as:

• government health administration authorities;

• private health insurers;

• health maintenance 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 health maintenance organizations that control or significantly influence purchases of healthcare products.

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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. In March 2010, President Obama signed into law a legislative overhaul of the U.S. healthcare system, known as the Patient Protection and Affordable Care Act of 2010, as amended by the Healthcare and Education Affordability Reconciliation Act of 2010 (PPACA). As a result of this new legislation, substantial changes could be made to the current system for paying for healthcare in the United States, including changes made in order to extend medical benefits to those who currently lack insurance coverage. The long-term ramifications of PPACA remain unclear and many details regarding implementation of PPACA are yet to be determined, however the cost-containment measures that healthcare providers are instituting and the results of healthcare reforms may negatively impact the commercial prospects of one or more of our vaccine candidates currently in development.

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 100 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 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 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.

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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. In addition to infringement claims against us, we may become a party to other patent litigation and other proceedings, including interference proceedings declared by the U.S. Patent and Trademark Office and opposition proceedings in the European Patent Office, regarding intellectual property rights with respect to our products and technology.

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.

Interference proceedings brought by the U.S. Patent and Trademark Office may be necessary to determine the priority of inventions with respect to our patent applications or those of our collaborators or licensors. Litigation or interference proceedings may fail and, even if successful, may result in substantial costs and distraction to our management. 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.

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 expect that we will need to license intellectual property from third-parties in the future 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 VLP technology for use in human vaccines in certain fields of use, is non-exclusive. These applications are very significant to our business. If each milestone is achieved for any particular vaccine candidate, we would likely be obligated to pay an aggregate of $14 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 $0.2 million per year. We are currently in discussion with Wyeth to potentially amend the agreement and restructure a $3 million milestone payment owed as a result of CPLB’s

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initiation of a Phase 3 clinical trial for its seasonal influenza VLP vaccine candidate in the third quarter of 2014; however, there is no guarantee that Wyeth will agree to such an amendment in which case Novavax would be obligated to promptly pay the milestone payment. An additional milestone payment associated with commercialization may also be triggered by CPLB activities and there is no guarantee that Wyeth would agree to restructure such milestone payment through another amendment.

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.

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 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 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 biopharmaceutical companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. From January 1, 2015 through March 23, 2015, the closing sale price of our common stock has been as low as $5.74 per share and as high as $9.71 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 and other matters affecting our business and results, regardless of accuracy;

• changes in government regulations;

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• 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;

• 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 influenza;

• 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 emerging and biopharmaceutical 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.

Provisions of our Certificate of Incorporation and 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

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of the common stock you purchase in this offering. Based on the assumed public offering of 18,022,657 shares at the assumed price of $9.71 per share (the closing price on The NASDAQ Global Select Market on March 19, 2015), 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 $1.31 per share as of December 31, 2014, after giving effect to this offering, if you purchase shares of common stock in this offering, you will suffer immediate and substantial dilution of $8.40 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 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 the advancement of our lead vaccine candidates, including the preparation and potential initiation of Phase 3 clinical trials of our elderly RSV and maternal RSV programs, as well as our other clinical and pre-clinical research programs and general corporate purposes, including working capital, product development, manufacturing and process development expenditures and capital expenditures, as well as acquisitions and other strategic purposes. Pending the application of the net proceeds, we expect to invest the proceeds in investment-grade, interest-bearing instruments or other securities.

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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, 2014 was approximately $162.4 million, or approximately $0.68 per share of common stock based upon 238,831,864 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, 2014.

After giving effect to the sale by us of 18,022,657 shares of common stock at the price of $9.71 per share (the closing price on The NASDAQ Global Select Market on March 19, 2015), 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, 2014 would have been approximately $337.2 million, or $1.31 per share. This would represent an immediate increase in net tangible book value of $0.63 per share to our existing stockholders and an immediate dilution in net tangible book value of $8.40 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			$	9.71
Net tangible book value per share as of December 31, 2014	$	0.68
Increase in net tangible book value per share attributable to the offering	$	0.63
As-adjusted net tangible book value per share after giving effect to the offering			$	1.31
Dilution in net tangible book value per share to new investors in the offering			$	8.40

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, 2014:

• 16,963,098 shares of our common stock reserved for issuance upon the exercise of outstanding stock options at a weighted average exercise price of $3.23 per share;

• 1,619,202 shares of our common stock reserved for issuance under our Employee Stock Purchase Plan; and

• 4,531,369 shares of our common stock reserved for future awards under our 2005 Stock Incentive Plan.

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, 2014 and no issuance of up to 2,703,398 shares of common stock that we may sell to the underwriter upon exercise of its 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 2,703,398 additional shares of common stock at the assumed public offering price of $9.71 per share, the pro forma as adjusted net tangible book value after this offering would be approximately $1.40 per share, representing an increase in net tangible book value of approximately $0.72 per share to existing stockholders and immediate dilution in net tangible book value of approximately $8.31 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 (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 sections titled “Backup Withholding and Information Reporting” and “Additional Withholding and Information Reporting

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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 common stock continues to be regularly traded on an established securities market and such Non-U.S. Holder does not own and is not

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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 of (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, 2017. In the case of payments made to a foreign entity, as a beneficial owner or as an intermediary, the tax generally will be imposed, subject to certain exceptions, unless such entity is in compliance with its applicable requirements under FATCA, and provides applicable required information if any. In the case of payments made to a “foreign financial institution,” as defined under FATCA, (including, among other entities, an investment fund) such requirements under FATCA may include that such entity (1) enters into (or is otherwise subject to) and complies with an agreement with the U.S. government, or a “FATCA Agreement,” or (2) complies with applicable foreign law enacted to implement an intergovernmental agreement between the United States and a foreign jurisdiction, or an “IGA,” in either case to, among other things, collect and provide to the U.S. or other relevant tax authorities certain information regarding U.S. account holders of such institution. In the case of payments made to a foreign entity that is not a foreign

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financial institution (as a beneficial owner), such requirements may include that such foreign entity provides the withholding agent with a certification that it does not have any “substantial U.S. owner” (generally, any specified U.S. person that directly or indirectly owns more than a specified percentage of such entity) or that identifies its substantial U.S. owners. If our common stock is held through a foreign financial institution that enters into (or is otherwise subject to) a FATCA Agreement, such foreign financial institution (or, in certain cases, a person paying amounts to such foreign financial institution) may be required, subject to certain exceptions, to withhold such tax on payments of dividends and proceeds in the situations described above.

Prospective investors should consult their own tax advisors regarding the possible impact of these rules 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 this 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

We are offering the shares of common stock described in this prospectus supplement through a number of underwriters. J.P. Morgan Securities LLC and Citigroup Global Markets Inc. are acting as joint book-running managers of the offering and as representatives of the underwriters. We have entered into an underwriting agreement with the underwriters. Subject to the terms and conditions of the underwriting agreement, we have agreed to sell to the underwriters, and each underwriter has severally agreed to purchase, at the public offering price less the underwriting discounts and commissions set forth on the cover page of this prospectus supplement, the number of shares of common stock listed next to its name in the following table:

Name	Number of shares
J.P. Morgan Securities LLC
Citigroup Global Markets Inc.
Total

The underwriters are committed to purchase all the common shares offered by us if they purchase any shares. The underwriting agreement also provides that if an underwriter defaults, the purchase commitments of non-defaulting underwriters may also be increased or the offering may be terminated.

The underwriters propose to offer the common shares directly to the public at the public offering price set forth on the cover page of this prospectus supplement and to certain dealers at that price less a concession not in excess of $     per share. After the public offering of the shares, the offering price and other selling terms may be changed by the underwriters. Sales of shares made outside of the United States may be made by affiliates of the underwriters.

The underwriters have an option to buy up to      additional shares of common stock from us. The underwriters have 30 days from the date of this prospectus supplement to exercise this option. If any shares are purchased with this option, the underwriters will purchase shares in approximately the same proportion as shown in the table above. If any additional shares of common stock are purchased, the underwriters will offer the additional shares on the same terms as those on which the shares are being offered.

The underwriting fee is equal to the public offering price per share of common stock less the amount paid by the underwriters to us per share of common stock. The underwriting fee is $     per share. The following table shows the per share and total underwriting discounts and commissions to be paid to the underwriters assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares.

	Without option exercise	With option exercise
Per share	$	$
Total	$	$

We estimate that the total expenses of this offering, including registration, filing and listing fees, printing fees and legal and accounting expenses, but excluding the underwriting discounts and commissions, will be approximately $250,000. The underwriters have agreed to reimburse us for certain of our expenses associated with this offering.

A prospectus in electronic format may be made available on the web sites maintained by one or more underwriters, or selling group members, if any, participating in the offering. The underwriters may agree to allocate a number of shares to underwriters and selling group members for sale to their online brokerage account holders. Internet distributions will be allocated by the representatives to underwriters and selling group members that may make Internet distributions on the same basis as other allocations.

We have agreed, subject to limited exceptions, that we will not (i) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise dispose of, directly or indirectly, or file with the SEC a registration statement under the Securities Act of 1933 relating to, any shares of our common stock or

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securities convertible into or exchangeable or exercisable for any shares of our common stock, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, or (ii) enter into any swap or other arrangement that transfers all or a portion of the economic consequences associated with the ownership of any shares of common stock or any such other securities (regardless of whether any of these transactions are to be settled by the delivery of shares of common stock or such other securities, in cash or otherwise), in each case without the prior written consent of J.P. Morgan Securities LLC and Citigroup Global Markets Inc. for a period of 60 days after the date of this prospectus supplement, other than (A) the Shares to be sold hereunder; (B) any shares of common stock of the Company issued upon the exercise of options granted under Company stock plans as are in existence on the date hereof and described in or incorporated by reference in this prospectus; (C) shares of restricted stock and options or awards to purchase shares of common stock issued (whether or not pursuant to a Company stock plan) to induce personnel to accept employment with the Company in an aggregate amount not to exceed 2% of the outstanding common stock of the Company as of the date hereof; (D) shares of common stock issued or to be issued in connection with any business combination, acquisition, in-license or strategic investment, provided that (y) such shares of common stock so issued shall not exceed 5% of the outstanding common stock of the Company as of the date hereof and (z) each individual or entity to whom any such shares of common stock are issued signs and delivers a “lock-up” agreement. Notwithstanding the foregoing, if (1) during the last 17 days of the 60-day restricted period, we issue an earnings release or material news or a material event relating to our company occurs; or (2) prior to the expiration of the 60-day restricted period, we announce that we will release earnings results during the 16-day period beginning on the last day of the 60-day period, the restrictions described above shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

Our directors and executive officers have entered into lock-up agreements with the underwriters prior to the commencement of this offering pursuant to which each of these persons, with limited exceptions, for a period of 60 days after the date of this prospectus supplement, may not, without the prior written consent of J.P. Morgan Securities LLC and Citigroup Global Markets Inc., (1) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of our common stock or any securities convertible into or exercisable or exchangeable for our common stock (including, without limitation, common stock or such other securities which may be deemed to be beneficially owned by such directors and executive officers in accordance with the rules and regulations of the SEC and securities which may be issued upon exercise of a stock option or warrant), (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of any shares of our common stock or such other securities, whether any such transaction described in clause (1) above or this clause (2) is to be settled by delivery of common stock or such other securities, in cash or otherwise, or (3) make any demand for or exercise any right with respect to the registration of any shares of our common stock or any security convertible into or exercisable or exchangeable for our common stock. Notwithstanding the foregoing, if (1) during the last 17 days of the 60-day restricted period, we issue an earnings release or material news or a material event relating to our company occurs; or (2) prior to the expiration of the 60-day restricted period, we announce that we will release earnings results during the 16-day period beginning on the last day of the 60-day period, the restrictions described above shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event. Each of the lock-up agreements contain certain exceptions, including transfers of shares of common stock pursuant to a contract or plan meeting the requirements of Rule 10b5-1 under the Exchange Act that has been entered into by certain of our executive officers or the disposition of shares of common stock to the Company for the purpose of covering tax liabilities and and/or the exercise price in connection with the exercise of options to purchase shares of common stock awarded pursuant to our existing equity compensation plans.

We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act of 1933.

Our common stock is listed on the Nasdaq Global Select Market under the symbol “NVAX.”

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In connection with this offering, J.P. Morgan Securities LLC on behalf of the underwriters may engage in stabilizing transactions, which involves making bids for, purchasing and selling shares of common stock in the open market for the purpose of preventing or retarding a decline in the market price of the common stock while this offering is in progress. These stabilizing transactions may include making short sales of the common stock, which involves the sale by the underwriters of a greater number of shares of common stock than they are required to purchase in this offering, and purchasing shares of common stock on the open market to cover positions created by short sales. Short sales may be “covered” shorts, which are short positions in an amount not greater than the underwriters’ option referred to above, or may be “naked” shorts, which are short positions in excess of that amount. The underwriters may close out any covered short position either by exercising their option to purchase additional shares, in whole or in part, or by purchasing shares in the open market. In making this determination, the underwriters will consider, among other things, the price of shares available for purchase in the open market compared to the price at which the underwriters may purchase shares through their option to purchase additional shares. 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 common stock in the open market that could adversely affect investors who purchase in this offering. To the extent that the underwriters create a naked short position, they will purchase shares in the open market to cover the position.

The underwriters have advised us that, pursuant to Regulation M of the Securities Act of 1933, they may also engage in other activities that stabilize, maintain or otherwise affect the price of the common stock, including the imposition of penalty bids. This means that if the representatives of the underwriters purchase common stock in the open market in stabilizing transactions or to cover short sales, the representatives can require the underwriters that sold those shares as part of this offering to repay the underwriting discount received by them.

These activities may have the effect of raising or maintaining the market price of the common stock or preventing or retarding a decline in the market price of the common stock, and, as a result, the price of the common stock may be higher than the price that otherwise might exist in the open market. If the underwriters commence these activities, they may discontinue them at any time. The underwriters may carry out these transactions on the Nasdaq Global Select Market, in the over-the-counter market or otherwise.

In addition, in connection with this offering certain of the underwriters (and selling group members) may engage in passive market making transactions in our common stock on the Nasdaq Stock Market prior to the pricing and completion of this offering. Passive market making consists of displaying bids on the Nasdaq Stock Market no higher than the bid prices of independent market makers and making purchases at prices no higher than these independent bids and effected in response to order flow. Net purchases by a passive market maker on each day are generally limited to a specified percentage of the passive market maker’s average daily trading volume in the common stock during a specified period and must be discontinued when such limit is reached. Passive market making may cause the price of our common stock to be higher than the price that otherwise would exist in the open market in the absence of these transactions. If passive market making is commenced, it may be discontinued at any time.

Certain of the underwriters and their affiliates have provided in the past to us and our affiliates and may provide from time to time in the future certain commercial banking, financial advisory, investment banking and other services for us and such affiliates in the ordinary course of their business, for which they have received and may continue to receive customary fees and commissions. In addition, from time to time, certain of the underwriters and their affiliates may effect transactions for their own account or the account of customers, and hold on behalf of themselves or their customers, long or short positions in our debt or equity securities or loans, and may do so in the future.

Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the securities offered by this prospectus supplement in any jurisdiction where action for that purpose is required. The securities offered by this prospectus supplement may not be offered or sold, directly or indirectly, nor may this prospectus supplement or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that

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jurisdiction. Persons into whose possession this prospectus supplement comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus supplement. This prospectus supplement does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus supplement in any jurisdiction in which such an offer or a solicitation is unlawful.

Notice to Prospective Investors in the United Kingdom

This document is only being distributed to and is only directed at (i) persons who are outside the United Kingdom or (ii) to investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the “Order”) or (iii) high net worth entities, and other persons to whom it may lawfully be communicated, falling with Article 49(2)(a) to (d) of the Order (all such persons together being referred to as “relevant persons”). The securities are only available to, and any invitation, offer or agreement to subscribe, purchase or otherwise acquire such securities will be engaged in only with, relevant persons. Any person who is not a relevant person should not act or rely on this document or any of its contents.

Notice to Prospective Investors in the European Economic Area

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a “Relevant Member State”), from and including the date on which the European Union Prospectus Directive (the “EU Prospectus Directive”) was implemented in that Relevant Member State (the “Relevant Implementation Date”) an offer of securities described in this prospectus supplement may not be made to the public in that Relevant Member State prior to the publication of a prospectus in relation to the shares which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the EU Prospectus Directive, except that, with effect from and including the Relevant Implementation Date, an offer of securities described in this prospectus supplement may be made to the public in that Relevant Member State at any time:

• to any legal entity which is a qualified investor as defined under the EU 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 EU Prospectus Directive); or

• in any other circumstances falling within Article 3(2) of the EU Prospectus Directive, provided that no such offer of securities described in this prospectus supplement shall result in a requirement for the publication by us of a prospectus pursuant to Article 3 of the EU Prospectus Directive.

For the purposes of this provision, the expression an “offer of securities to the public” in relation to any securities 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 securities to be offered so as to enable an investor to decide to purchase or subscribe for the securities, as the same may be varied in that Member State by any measure implementing the EU Prospectus Directive in that Member State. The expression “EU Prospectus Directive” means Directive 2003/71/EC (and any amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State) and includes any relevant implementing measure in each Relevant Member State, and the expression “2010 PD Amending Directive” means Directive 2010/73/EU.

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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 restreint 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;

• 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

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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:

• 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. at December 31, 2014 and for the year then ended, incorporated by reference in this Prospectus and Registration Statement, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, which is incorporated by reference, and are included in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

The consolidated financial statements as of December 31, 2013 and for the two years then ended, incorporated by reference in this prospectus and elsewhere in the registration statement, have been so incorporated by reference in reliance upon the report of Grant Thornton LLP, independent registered public accountants, upon the authority of said 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.

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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 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, 2014, filed with the SEC on February 27, 2015;

• our Definitive Proxy Statement on Schedule 14A, filed on April 30, 2014 (excluding those portions that are not incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2013); 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 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

Novavax, Inc.
  
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.

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 under the symbol “NVAX.” On January 23, 2014, the closing price of our common stock as reported on the NASDAQ Global Select Market was $6.40 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 24, 2014.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS		2
PROSPECTUS SUMMARY		2
NOVAVAX		2
RISK FACTORS		3
USE OF PROCEEDS		3
PLAN OF DISTRIBUTION		3
DESCRIPTION OF OUR CAPITAL STOCK		5
DESCRIPTION OF WARRANTS		8
DESCRIPTION OF OUR UNITS		9
DIVIDEND POLICY		9
LEGAL MATTERS		10
EXPERTS		10
WHERE YOU CAN FIND MORE INFORMATION		10
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE		11

i

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 January 24, 2014. By using a shelf registration statement, we may, from time to time, issue and sell an indeterminate amount of common stock, preferred stock, warrants and/or units consisting of our common stock, preferred stock and warrants in one or more offerings. 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.

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 biopharmaceutical company focused on the discovery, development and commercialization of recombinant protein nanoparticle vaccines and adjuvants. Our vaccine technology platform is based on proprietary recombinant nanoparticle vaccine technology that includes virus-like particles vaccines and recombinant protein micelle vaccines. These vaccine candidates are genetically engineered three-dimensional nanostructures that incorporate immunologically important recombinant proteins. Our vaccine product pipeline targets a variety of infectious diseases with candidates currently in clinical development for seasonal influenza, pandemic influenza and respiratory syncytial virus. We operate in one business segment: developing recombinant vaccines.

Through our Sweden-based subsidiary, Novavax AB (formerly Isconova AB), we are also developing patented technology for the production of immune stimulating saponin-based adjuvants that we expect to utilize in conjunction with our pandemic influenza vaccine candidates and potentially with other vaccine candidates that may benefit from such an adjuvant. The Matrix^TM technology utilizes selected Quillaja saponaria fractions, which form separate matrix structures, to develop modern, multi-purpose immune-modulating adjuvant products for a broad range of vaccine applications. We acquired the Matrix^TM technology through our acquisition of Isconova AB in the third quarter of 2013 because we believe this saponin-based adjuvant technology is a powerful complement to our recombinant vaccine programs. Our lead adjuvant for human applications, Matrix-M^TM, is in clinical trials with our partner Genocea Biosciences and is planned for a clinical trial in combination with our H7N9 vaccine candidate in the first quarter of 2014 under our contract with the Department of Health and Human Services, Biomedical Advanced Research and Development Authority.

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In 2009, we formed a joint venture with Cadila Pharmaceuticals Limited (“Cadila”) named CPL Biologicals Private Limited (“CPLB”) to develop and manufacture vaccines, biological therapeutics and diagnostics in India. CPLB is owned 20% by us and 80% by Cadila. CPLB operates a state-of-the-art manufacturing facility for the production of influenza vaccine and other vaccine candidates. CPLB is actively developing a number of vaccine candidates that were genetically engineered by Novavax. CPLB’s rabies vaccine candidate is expected to begin a Phase 1 clinical trial in India in the first half of 2014. We continue to account for our investment in CPLB using the equity method. Since the carrying value of our initial investment was nominal and there is no guarantee or commitment to provide future funding, we have not recorded nor do we expect to record losses related to this investment in the future.

Novavax was incorporated in 1987 under the laws of the State of Delaware. Our principal executive offices are located at 9920 Belward Campus Drive, Rockville, Maryland, 20850. 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.

RISK FACTORS

Investing in our securities involves a high degree of risk. For a discussion of the factors you should carefully consider before deciding to purchase any of our securities, please review the cautionary information included in the documents incorporated by reference, including “Part I, Item 1A — Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2012, filed with the SEC on March 12, 2013, and “Part II, Item 1A — Risk Factors” in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2013, filed with the SEC on November 12, 2013. The risks and uncertainties described in those sections 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.

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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.

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.

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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.

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 amended and restated certificate of incorporation, as amended through June 13, 2013, 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, as well as our registration rights agreement that is currently in effect, which is also included as an exhibit to the registration statement of which this prospectus is a part.

General

Our authorized capital stock consists of: (1) 300,000,000 shares of common stock, par value $0.01 per share, of which 208,673,064 shares were outstanding as of January 23, 2014, and (2) 2,000,000 shares of preferred stock, par value $0.01 per share, none of which were outstanding on January 23, 2014.

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.

Except as discussed below in “Registration Rights,” 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 January 23, 2014, the closing price of our common stock as reported on the NASDAQ Global Select Market was $6.40 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 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.

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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;

• 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.

Registration Rights

Holders of our common stock issued in connection with the stock purchase agreement dated as of March 31, 2009, by and between the Company and Satellite Overseas (Holdings) Limited (together with its affiliates and any assignees or transferees) are entitled to rights with respect to the registration under the Securities Act of their shares of common stock. These registration rights are contained in our registration rights agreement and are described below. The registration rights granted pursuant to the registration rights agreement will expire when the holder is able to sell all of its shares pursuant to Rule 144 under the Securities Act in any 90 day period.

Piggyback Registration Rights

If we register any securities for public sale, the holders with piggyback registration rights under the registration rights agreement have the right to include their shares in the registration, subject to specified exceptions. In accordance with the terms of the registration rights agreement, we have received a waiver of these piggyback registration rights with respect to the registration for this offering. We must pay all expenses, except for taxes and underwriting discounts and commissions, incurred in connection with the exercise of piggyback registration rights. The underwriters in any underwritten offering have the right to limit the number of shares included in a registration statement filed in response to the exercise of these registration rights.

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Provisions of our Amended and Restated Certificate of Incorporation, Amended and Restated By-laws, and Delaware Law

Certain provisions of our 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 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 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 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 amended and restated certificate of incorporation provides that our stockholders may not act by written consent. In addition, our 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.

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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 662/3% 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.

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;

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• 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.

As of January 23, 2014, the Company has no outstanding 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.

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.

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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 audited financial statements, schedule and management’s assessment of the effectiveness of internal control over financial reporting incorporated by reference in this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the reports of Grant Thornton LLP, independent registered public accountants, upon the authority of said firm as experts in accounting.

The consolidated financial statements of Isconova incorporated by reference in this prospectus and elsewhere in the registration statement have been so incorporated by reference in reliance upon the report of Öhrlings PricewaterhouseCoopers AB, independent registered public accountants, upon the authority of said firm as experts in accounting and auditing in giving said report.

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, 2012, filed with the SEC on March 12, 2013;

• our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2013, filed with the SEC on May 9, 2013, June 30, 2013, filed with the SEC on August 8, 2013 and September 30, 2013, filed with the SEC on November 12, 2013;

• our Current Reports on Form 8-K, filed with the SEC on January 30, 2013, April 29, 2013, June 4, 2013, June 17, 2013, June 17, 2013, June 28, 2013, July 5, 2013, July 8, 2013, August 2, 2013, August 22, 2013, September 24, 2013, September 27, 2013 and October 30, 2013; 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.
9920 Belward Campus Drive
Rockville, MD 20850
(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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$175,000,000

Novavax, Inc.

Common Stock

 

Prospectus Supplement

 

Joint Book-Running Managers   
  

J.P. Morgan                     Citigroup

The date of this Prospectus Supplement is            , 2015