Vaxart, Inc.: Form 10-Q for the period ended Mar 31, 2025

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our condensed consolidated financial statements and related notes included elsewhere in this Quarterly Report on Form 10-Q and with our audited consolidated financial statements included in our Annual Report on Form 10-K filed with the SEC on March 20, 2025. This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “safe harbor” created by those sections. Forward-looking statements are based on our management’s beliefs and assumptions and on information currently available to our management. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “goal,” “would,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “project,” “predict,” “potential” and similar expressions intended to identify forward-looking statements and reflect our beliefs and opinions on the relevant subject. Our actual results could differ materially from those discussed in the forward-looking statements. Factors that could cause or contribute to these differences include those discussed below and in this Quarterly Report on Form 10-Q. The forward-looking statements included in this Quarterly Report on Form 10-Q are made only as of the date hereof. These statements are based upon information available to us as of the filing date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and we caution investors against unduly relying upon these statements. In all events, we undertake no obligation to revise or update any forward-looking statements, whether as a result of new information, change in circumstances, future events or otherwise, and you are advised to consult any additional disclosures that we may make directly to you or through reports that we, in the future, may file with the SEC, including annual reports on Form 10-K, quarterly reports on Form 10-Q and current reports on Form 8-K.

Company Overview and Background

We are a clinical-stage biotechnology company primarily focused on the development of oral recombinant vaccines based on our Vector-Adjuvant-Antigen Standardized Technology (“VAAST”) proprietary oral vaccine platform. We are developing prophylactic vaccine candidates that target a range of infectious diseases, including norovirus (a widespread cause of acute gastroenteritis), coronavirus including SARS-CoV-2 (the virus that causes coronavirus disease 2019 (“COVID-19”)), and influenza. In addition, we have generated preclinical data for our first therapeutic vaccine candidate targeting cervical cancer and dysplasia caused by human papillomavirus (“HPV”). Our oral vaccines are designed to generate broad and durable immune responses that may protect against a wide range of infectious diseases and may be useful for the treatment of chronic viral infections and cancer. Our investigational vaccines are administered using a room temperature-stable tablet, rather than by injection.

Vaxart Biosciences, Inc. was originally incorporated in California under the name West Coast Biologicals, Inc. in March 2004 and changed its name to Vaxart, Inc. (“Private Vaxart”) in July 2007, when it reincorporated in the state of Delaware. On February 13, 2018, Private Vaxart completed a reverse merger (the “Merger”) with Aviragen Therapeutics, Inc. (“Aviragen”), pursuant to which Private Vaxart survived as a wholly owned subsidiary of Aviragen. Under the terms of the Merger, Aviragen changed its name to Vaxart, Inc. and Private Vaxart changed its name to Vaxart Biosciences, Inc.

Our Product Pipeline

We are developing the following tablet vaccine candidates, which are all based on our proprietary platform:

• Norovirus Vaccine. Norovirus is the leading cause of acute gastroenteritis symptoms, such as vomiting and diarrhea, among people of all ages in the United States. Each year, on average in the United States, norovirus causes 19 to 21 million cases of acute gastroenteritis and contributes to 109,000 hospitalizations and 900 deaths, mostly among young children and older adults. Virtually all norovirus disease is caused by norovirus GI and GII genotypes, and we are developing a bivalent vaccine candidate designed to protect against both.

Adult and Elderly. In September 2023, we announced that our Phase 2 GI.1 norovirus challenge study evaluating the safety, immunogenicity, and clinical efficacy of the GI.1 component of our first-generation bivalent norovirus vaccine candidate met five of six primary endpoints based on preliminary topline data. The study achieved its primary endpoints of a statistically significant 29% relative reduction in the rate of norovirus infection between the vaccinated and placebo arms, a strong induction of norovirus-specific immunoglobulin A (IgA) and immunoglobulin G (IgG) antibodies, and other immune response endpoints.

Vaccination also led to a 21% relative reduction in norovirus acute gastroenteritis in the vaccine arm compared to placebo, but this was not statistically significant. In prespecified analyses, the study also showed an 85% relative decrease in viral shedding in the vaccine arm compared with placebo and no statistically significant difference in disease severity in the vaccinated cohort compared with placebo. The vaccine candidate was also safe and well tolerated with no vaccine-related serious adverse events.

Based on our norovirus clinical data findings to date, our norovirus oral vaccination induces mucosal and systemic immune responses. Norovirus oral vaccination reduced shedding and infection in a rigorous human challenge model. Based on our machine learning and evaluation of more than 13 different immune parameters, norovirus vaccination protection most tightly associates with making a functional antibody response to norovirus in the serum (“NBAA”) and norovirus specific fecal IgA antibodies. Because of the strong induction of mucosal IgA due to the oral vaccination and potential read through into the serum, we believe that this likely means that a functional fecal IgA response is probably critical for protection against norovirus infection.

In the second half of 2024, we received constructive feedback from the U.S. Food and Drug Administration (“FDA”) on our data for potential correlates of protection and next steps for our norovirus program. While we believe we have identified a functional antibody response that may be associated with protection for norovirus, the FDA requested new clinical data before proceeding with further review of our potential correlate.

In 2024, we also created new, second-generation norovirus GI.1 and GII.4 constructs. Based on preclinical data, the second-generation norovirus GI.1 and GII.4 constructs are more potent than the first-generation norovirus constructs we previously evaluated in clinical trials.

With advice from advisors and infectious disease experts, we decided to proceed with a Phase 1, open label, dose ranging clinical trial evaluating our second-generation oral norovirus vaccine constructs head-to-head against our first-generation constructs. The trial will measure safety and immunogenicity, including immune parameters that have correlated to protection in our Phase 2 GI.1 norovirus challenge study. The Phase 1 trial initiated in March 2025 and topline data is expected in the middle of 2025.

If the Phase 1 trial is successful, the next step, pending a partnership or other funding, would be to conduct a Phase 2b safety and immunogenicity study that could potentially begin as early as the second half of 2025. This Phase 2b trial would be followed by an End of Phase 2 meeting with the FDA. A Phase 3 trial could then begin as early as 2026, pending a successful End of Phase 2 meeting and funding.

Breastfeeding Mothers. In 2022, we partnered with the Bill & Melinda Gates Foundation to execute a Phase 1 norovirus bivalent vaccine candidate study in 76 healthy, lactating post-partum, women volunteers, to determine the impact of our norovirus vaccine on breast milk norovirus-specific IgA and its potential presence, post-breastfeeding, within infant fecal samples. The study was randomized, double-blinded, and placebo controlled and evaluated the safety, tolerability, and immunogenicity of the placebo cohorts and two vaccine cohorts: medium dose (1×1011 IU) and high dose (2×1011 IU). Passive transfer of antibodies from mother to infant that are induced in milk may protect breastfeeding infants from infectious pathogens. We initiated this study in the fourth quarter of 2023 and announced positive top line results in April 2024. Top line results showed antibodies rose in lactating mothers who received the high dose of our bivalent vaccine candidate. Specifically, serum antibodies to norovirus rose on average 5.6 fold in response to the GI.1 virus strain and 4.4 fold in response to the GII.4 virus strain and breast milk antibodies to norovirus rose on average 4.0 fold in response to the GI.1 virus strain and 6.0 fold in response to the GII.4 virus strain. The vaccine was well tolerated with no vaccine-related serious adverse events and no dose-limiting pharmacotoxicity. As a grant recipient from the Bill & Melinda Gates Foundation, Vaxart has agreed to a global access commitment for use of its bivalent norovirus vaccine candidate, if proven effective and approved, in breastfeeding mothers from low- and middle-income countries.

• Coronavirus Vaccine. COVID-19, a severe respiratory tract infection caused by the virus SARS-CoV-2, is a major cause of hospitalization and death in the U.S. and worldwide. According to the CDC, an outbreak of COVID-19 began in Wuhan, China, in late 2019 and rapidly spread worldwide. While most COVID-19 restrictions, such as stay-at-home orders, have been lifted, COVID-19 continues to spread and remains a public health threat, not least due to the continuing emergence of new variants.

In January 2024, we were awarded a contract by the U.S. Biomedical Advanced Research and Development Authority (“HHS BARDA”), a division of the Administration for Strategic Preparedness and Response (“ASPR”) within the U.S. Department of Health and Human Services (“HHS”), for $9.3 million to fund preparation for a Phase 2b clinical study involving 10,000 patients. Vaxart executed on the deliverables and received all $9.3 million of cash payments related to this contract in 2024. BARDA and Vaxart are currently discussing contract closeout for this contract.

In June 2024, we entered into an agreement (as modified or amended from time to time, the “2024 ATI-RRPV Contract”) with Advanced Technology International (“ATI”), the Rapid Response Partnership Vehicle’s Consortium Management Firm funded by HHS BARDA. The 2024 ATI-RRPV Contract provides for funding of up to $460.7 million to conduct the Phase 2b study, manufacture a COVID-19 vaccine candidate targeting the KP.2 strain, and acquire an approved mRNA vaccine targeting the KP.2 strain. In February 2025, we entered into Modification No. 5 (the “Modification”) to the 2024 ATI-RRPV Contract. The Modification increased the total amount of funding available for payment to approximately $240.1 million. Subsequently, in February 2025, we received written notification directing the Company to stop work on the 2024 ATI-RRPV Contract, with the exception that we could continue effort associated with the per protocol follow-up for the 400-person cohort. The stop work order was in effect for a period of 90 days and, that within a period of 90 days, ATI, as directed by the U.S. Government, will either cancel the stop work order, extend the stop work, or terminate the work covered by the 2024 ATI-RRPV Contract. Subsequently, in April 2025, the Company received written notification from ATI in the form of a stop work order lift (the “Lift Notice”) that the stop work order had been lifted and that the Company may resume incurring costs, participating in meetings, and communicating with the Government and ATI concerning the project award. The Lift Notice required further discussion between the Company and HHS BARDA regarding costs, timelines, and regulatory pathway agreement. Subsequent to the Company’s receipt of the Lift Notice, the Company had a virtual meeting with HHS BARDA wherein the Company was told that it could proceed with screening for the 10,000-participant portion of the Phase 2b trial.

The Phase 2b study is a double-blind, multi-center, randomized, comparator-controlled study to determine the relative efficacy, safety, and immunogenicity of Vaxart’s oral pill COVID-19 vaccine candidate against an approved mRNA COVID-19 injectable vaccine in adults previously immunized against COVID-19 infection. The study design anticipates enrolling approximately 10,400 healthy adults 18 years and older in the U.S. with approximately 5,200 receiving our COVID-19 vaccine candidate and approximately 5,200 receiving an approved mRNA comparator. The study will strive to enroll participants in line with U.S. demographics, as well as including at least 25% over the age of 65.

The Phase 2b study will measure efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and the incidence of adverse events. The primary endpoint is relative efficacy of Vaxart’s COVID-19 vaccine candidate compared to an approved mRNA comparator for the prevention of symptomatic disease. Primary efficacy analysis will be performed when all participants have either discontinued or completed a study visit 12 months post-vaccination.

In the second half of 2024, we initiated and completed enrollment of the sentinel cohort of the Phase 2b study consisting of 400 individuals comparing our XBB COVID-19 vaccine candidate against an approved mRNA XBB comparator. In January 2025, an independent data safety monitoring board (“DSMB”) recommended the study to proceed without modifications based on initial safety assessment of 30-day data from the sentinel cohort. If we receive approval from HHS BARDA, we will progress to the next part of the study to enroll approximately 10,000 participants comparing our KP.2 COVID-19 vaccine candidate against an approved mRNA KP.2 comparator.

• Influenza Vaccine. Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. An estimated one billion cases of seasonal influenza occur annually worldwide, of which three to five million cases are considered severe, causing 290,000 to 650,000 deaths per year. In the United States, between 9,000,000 to 41,000,000 people catch influenza annually, between 140,000 and 710,000 people are hospitalized with complications of influenza, and between 12,000 and 52,000 people die from influenza and its complications each year.

Monovalent influenza vaccine. In 2018, we completed a Phase 2 challenge study of our H1N1 flu vaccine candidate, which was funded through a $15.7 million contract with HHS BARDA. We announced that, in healthy volunteers immunized and then experimentally infected with H1 influenza, our H1 influenza oral tablet vaccine candidate reduced clinical disease by 39% relative to placebo. Fluzone, the market-leading injectable quadrivalent influenza vaccine, reduced clinical disease by 27%. Our tablet vaccine candidate also showed a favorable safety profile, indistinguishable from placebo.

We also presented data from the study demonstrating that our vaccine candidate elicited a significant expansion of mucosal homing receptor plasmablasts to approximately 60% of all activated B cells. We believe these mucosal plasmablasts are a key indicator of a protective mucosal immune response and a unique feature of our vaccine candidates.

Avian influenza vaccine. We continue to advance our avian influenza program. We previously published data demonstrating protection in a preclinical model against avian influenza after oral immunization (Clin Vaccine Immunol 2013). We recently created a new avian influenza vaccine candidate to cover the latest clade 2.3.4.4b. The new avian influenza vaccine was 100% protective against death in a robust ferret clade 2.3.4.4b challenge model compared to 0% survival in placebo treated animals. Additional details will be presented in upcoming scientific conferences and published in a scientific paper.

Next Steps

The Company intends to work with governments around the world to create pandemic monovalent influenza vaccines for emergency use or stockpiling, if requested. We are also continuing development of our preclinical seasonal influenza vaccine candidate.

• HPV Therapeutic Vaccine. Cervical cancer is the fourth most common cancer in women worldwide and in the United States with about 13,000 new cases diagnosed annually in the United States according to the National Cervical Cancer Coalition. Our first therapeutic oral vaccine candidate targets HPV 16 and HPV 18, the two strains responsible for 70% of cervical cancers and precancerous cervical dysplasia.

We are in the early stages of developing a bivalent HPV vaccine against HPV-16 and HPV-18, the strains responsible for approximately 70% of cases of cervical cancer. We plan to target the E6 and E7 gene products of each strain, which are the primary oncogenic proteins responsible for progression through the stages of CIN to invasive cervical cancer. In pre-clinical studies, we have demonstrated immunogenicity for both our HPV-16 and our HPV-18 vaccine candidates. Specifically, mice given our HPV-16 or HPV-18 vaccines induced T cell responses to HPV as measured by IFN gamma ELISPOT. In addition, our HPV-16 vaccine has demonstrated tumor growth suppression as well as increased survival in a robust HPV tumor model in mice.

Next Steps

We will need to make a regulatory filing to proceed with clinical trials for an HPV vaccine candidate. Our clinical plan is to test the vaccine candidate in subjects with cervical dysplasia related to HPV-16 or HPV-18, and to evaluate the ability of the vaccine candidate to clear HPV infection, reduce the cervical dysplasia score, and induce T cells known to be important in the clearance of HPV. The primary endpoint will be safety and the secondary endpoint will be immunogenicity by examining T cell responses. Although clinical responses will be tracked, it is expected that the first study may not be powered to obtain statistically significant efficacy readouts.

Antivirals

• Through the Merger, we acquired two royalty earning products, Relenza and Inavir. We also acquired three Phase 2 clinical stage antiviral compounds, of which we have discontinued independent clinical development. However, for one of these, Vapendavir, we have entered into an exclusive worldwide license agreement with Altesa Biosciences, Inc. (“Altesa”) in July 2021, permitting Altesa to develop and commercialize this capsid-binding broad-spectrum antiviral. In May 2025, Altesa announced positive topline results from its Phase 2 placebo-controlled study examining the effects of Vapendavir in chronic obstructive pulmonary disease patients challenged with rhinovirus.
• Relenza and Inavir are antivirals for the treatment of influenza, marketed by GlaxoSmithKline, plc (“GSK”) and Daiichi Sankyo Company, Limited (“Daiichi Sankyo”), respectively. We have earned royalties on the net sales of Relenza and Inavir in Japan. The last patent for Relenza expired in July 2019 based on information provided by Daiichi Sankyo, and the last patent for Inavir expires in August 2036. Sales of these antivirals vary significantly by quarter, because influenza virus activity displays strong seasonal cycles, and by year depending on the intensity and duration of the flu season, the impact COVID-19 has had, and may continue to have, on seasonal influenza, and competition from other antivirals such as Tamiflu and Xofluza.

Financial Operations Overview

Revenue

Non-Cash Royalty Revenue Related to Sale of Future Royalties

In April 2016, Aviragen sold certain royalty rights related to Inavir in the Japanese market for $20.0 million to HealthCare Royalty Partners III, L.P. (“HCRP”). Under the terms of our agreement with HCRP, during the first royalty interest period of April 1, 2016 through March 31, 2025, HCRP is entitled to the first $3.0 million and any cumulative remaining shortfall amount plus 15% of the next $1.0 million in royalties earned in each year commencing on April 1, with any excess revenue being retained by us. Further, during the second royalty interest period beginning April 1, 2025 and ending on December 24, 2029, HCRP is entitled to the first $2.7 million and any cumulative remaining shortfall amount plus 15% of the next $1.0 million in royalties, with any excess revenue being retained by us. A shortfall occurs when, during an annual period ending on March 31st, for the first royalty interest period of April 1, 2016 through March 31, 2025, royalty payments fall below $3.0 million; and $2.7 million for the second royalty interest period of April 1, 2025 and ending on December 24, 2029, excluding the period of April 1, 2028 through December 24, 2029. In the event there is a remaining cumulative remaining shortfall amount as of December 24, 2029, then, for so long as the Company continues to receive royalties from Daiichi Sankyo Company Limited (“Daiichi Sankyo”), the sum of those royalties will be paid to HCRP until the cumulative remaining shortfall amount has been paid in full.

We are not obligated to pay HCRP any royalty payment beyond what we are paid by Daiichi Sankyo. The cumulative remaining shortfall amount is the aggregate amount of the shortfall for each annual period, which was $4.4 million as of March 31, 2025.

Even though we do not currently retain the related royalties under the transaction, as the amounts are remitted to HCRP, we will continue to record revenue related to these royalties until the amount of the associated liability and related interest is fully amortized.

Revenue from Government Contracts

In January 2024, we were awarded the 2024 ASPR-BARDA Contract by HHS BARDA, with a base and all options value of $9.3 million. Under the 2024 ASPR-BARDA Contract, we received an award to support clinical trial planning activities for a Phase 2b clinical trial that would compare our XBB vaccine candidate to an mRNA comparator to evaluate efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and adverse events. Revenue from government contracts recognized on the 2024 ASPR-BARDA Contract was zero and $1.6 million for the three months ended March 31, 2025 and 2024, respectively, based on the achievement of certain milestones under the 2024 ASPR-BARDA Contract.

In June 2024, we entered into the 2024 ATI-RRPV Contract. In the second half of 2024, the 2024 ATI-RRPV Contract was modified to increase funding and expand the scope to include the manufacture of a vaccine candidate targeting the KP.2 strain and acquire an approved mRNA vaccine targeting the KP.2 strain. Pursuant to the 2024 ATI-RRPV Contract (as modified or amended from time to time), we may receive funding of up to $460.7 million to conduct a Phase 2b comparative study evaluating our oral pill COVID-19 vaccine candidate against an mRNA vaccine comparator approved by the FDA. The 2024 ATI-RRPV Contract makes available an aggregate amount of up to $240.1 million, consisting of firm fixed price amounts totaling $67.9 million and reimbursement of costs incurred in trial preparation and execution activities. The 2024 ATI-RRPV Contract further contemplates additional funding up to $220.6 million if we and HHS BARDA decide to continue with the Phase 2b comparative study. Revenue from government contracts recognized on the 2024 ATI-RRPV Contract was $19.3 million for the three months ended March 31, 2025 based on costs incurred and the achievement of firm fixed-price milestones under the 2024 ATI-RRPV Contract. For further information about the stop work order and the lift of the stop work order, see the section above titled “—Our Product Pipeline” in the “Coronavirus Vaccine” discussion.

Research and Development Expenses

Research and development expenses represent costs incurred on conducting research, such as developing our tablet vaccine platform, and supporting preclinical and clinical development activities of our tablet vaccine candidates. We recognize all research and development costs as they are incurred. Research and development expenses consist primarily of the following:

• employee-related expenses, which include salaries, benefits and stock-based compensation;
• expenses incurred under agreements with contract research organizations (“CROs”), that conduct clinical trials on our behalf;
• expenses incurred under agreements with contract manufacturing organizations (“CMOs”), that manufacture product used in the clinical trials;
• expenses incurred in procuring materials and for analytical and release testing services required to produce vaccine candidates used in clinical trials;
• process development expenses incurred internally and externally to improve the efficiency and yield of the bulk vaccine and tablet manufacturing activities;
• laboratory supplies and vendor expenses related to preclinical research activities;
• consultant expenses for services supporting our clinical, regulatory and manufacturing activities; and
• facilities, depreciation and allocated overhead expenses.

We do not allocate our internal expenses to specific programs. Our employees and other internal resources are not directly tied to any one research program and are typically deployed across multiple projects. Internal research and development expenses are presented as one total.

We have incurred significant external costs for CROs that conduct clinical trials on our behalf. We have captured these external costs for each vaccine program. We do not allocate external costs incurred on preclinical research or process development to specific programs.

The following table shows our period-over-period research and development expenses, identifying external costs that were incurred in each of our vaccine programs and, separately, on preclinical research and process development for the three months ended March 31, 2025 and 2024 (in thousands):

We expect to incur significant research and development expenses in 2025 and beyond as we advance our tablet vaccine candidates into and through clinical trials, pursue regulatory approval of our tablet vaccine candidates and prepare for a possible commercial launch, all of which will also require a significant investment in manufacturing and inventory related costs. To the extent that we enter into licensing, partnering or collaboration agreements, a significant portion of such costs may be borne by third parties.

The process of conducting clinical trials necessary to obtain regulatory approval is costly and time consuming. We may never succeed in achieving marketing approval for our tablet vaccine candidates. The probability of successful commercialization of our tablet vaccine candidates may be affected by numerous factors, including clinical data obtained in future trials, competition, manufacturing capability and commercial viability. As a result, we are unable to determine the duration and completion costs of our research and development projects or when and to what extent we will generate revenue from the commercialization and sale of any of our tablet vaccine candidates.

General and Administrative Expense

General and administrative expenses consist of personnel costs, insurance, allocated expenses and expenses for outside professional services, including legal, audit, accounting, public relations, market research and other consulting services. Personnel costs consist of salaries, benefits and stock-based compensation. Allocated expenses consist of rent, depreciation and other facilities-related expenses.

Results of Operations

As we continue to explore commercial opportunities, and plan to work with business partners, in both U.S. and international markets, we remain attentive to evolving global economic conditions, including uncertainties related to international trade policies, tariffs, and supply chain dynamics. Although these factors have not had a material impact on our operations to date, future changes in trade regulations, tariff structures, or logistical constraints could influence the cost, availability, or timing of materials, services and other components associated with the development of our tablet vaccines and manufacturing capabilities. We continue to monitor these developments closely to maintain operational efficiency and help mitigate potential future impacts.

The following table presents period-over-period changes in selected items in the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2025 and 2024 (in thousands, except percentages):

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Total Revenue

The following table summarizes the period-over-period changes in our revenues for the three months ended March 31, 2025 and 2024 (in thousands, except percentages):

Non-cash Royalty Revenue Related to Sale of Future Royalties

For the three months ended March 31, 2025 and 2024, non-cash royalty revenue related to sale of future royalties from Daiichi Sankyo was $1.6 million and $0.6 million, respectively. We continue to have non-cash royalty revenue as all royalties received for the three months ended March 31, 2025 and 2024 were required to be paid to HCRP.

Revenue from Government Contracts

For the three months ended March 31, 2025 and 2024, revenue from government contracts was $19.3 million and $1.6 million, respectively. The revenue from government contracts consists of the 2024 ASPR-BARDA Contract awarded to us in January 2024 and the 2024 ATI-RRPV Contract awarded to us in June 2024. Revenue from the 2024 ASPR-BARDA Contract was zero and $1.6 million for the three months ended March 31, 2025 and 2024, respectively. Revenue from the ATI-RRPV Contract was $19.3 million for the three months ended March 31, 2025.

Total Operating Expenses

The following table summarizes the period-over-period changes in our operating expenses for the three months ended March 31, 2025 and 2024 (in thousands, except percentages):

Research and Development

For the three months ended March 31, 2025, research and development expenses increased by $11.7 million, or 62%, compared to the three months ended March 31, 2024. The increase was primarily due to an increase in clinical trial expenses related to our COVID-19 and norovirus vaccine candidates, partially offset by a decrease in preclinical and manufacturing expenses.

General and Administrative

For the three months ended March 31, 2025, general and administrative expenses decreased by $2.2 million, or 30%, compared to the three months ended March 31, 2024. The decrease was primarily due to a decrease in stock-based compensation expense, personnel costs and legal and other professional fees.

Non-Operating Income (Expense)

The following table summarizes the period-over-period changes in our non-operating income for the three months ended March 31, 2025 and 2024 (in thousands, except percentages):

For the three months ended March 31, 2025, we recorded interest income of $0.4 million, a 13% decrease from the $0.5 million interest income recorded in the three months ended March 31, 2024. The decrease is primarily due to the decrease in our cash, cash equivalents and investments balance.

Non-cash interest expense related to sale of future royalties representing imputed interest on the unamortized portion of the sale of future royalties liability, increased to $1.0 million for the three months ended March 31, 2025, from the $0.8 million for the three months ended March 31, 2024, due to an increase in non-cash royalty revenue payable to HCRP.

Provision for Income Taxes

The following table summarizes the period-over-period changes in our provision for income taxes for the three months ended March 31, 2025 and 2024 (in thousands, except percentages):

The provision for income taxes was $95,000 and $45,000 for the three months ended March 31, 2025 and 2024, respectively. The tax charge relates to interest on an intercompany loan from a foreign subsidiary and a 5% withholding tax on royalty revenue earned on sales of Inavir in Japan, which is potentially recoverable as a foreign tax credit but expensed because we record a 100% valuation allowance against our deferred tax assets. The amount of income tax expense recorded is directly proportional to Inavir royalties, including the portion that we pass through to HCRP.

Liquidity and Capital Resources

We are a clinical-stage biotechnology company with no product sales. Our primary source of financing is from the sale and issuance of common stock as well as funding from HHS BARDA. In the past, we have also obtained funds from the issuance of common stock warrants, secured debt and preferred stock and from collaboration agreements.

In March 2025, the Company entered into an At the Market Offering Agreement (the “March 2025 ATM”) with Citizens JMP Securities, LLC (“Citizens”) and B. Riley Securities, Inc. (“B. Riley” and, together with Citizens, the “Managers”), pursuant to which the Company may offer and sell, from time to time through the Managers, shares of its common stock having an aggregate offering price of up to $50 million. The shares will be sold pursuant to an effective registration statement on Form S-3 (Registration Statement No. 333-270671), as previously filed with the U.S. Securities and Exchange Commission (the “SEC”). The Company filed a prospectus supplement, dated March 21, 2025, with the SEC in connection with the offer and sale of the shares under the March 2025 ATM. The Company will pay the Managers a placement fee of up to 3% of the gross sale price from each sale of the shares under the March 2025 ATM. As of March 31, 2025, the Company has not sold any shares under the March 2025 ATM.

In January 2024, we entered into a securities purchase agreement (the “2024 Securities Purchase Agreement”) with RA Capital Healthcare Fund, L.P. pursuant to which 15,384,615 shares of our common stock were sold to RA Capital Healthcare Fund, L.P. at an offering price of $0.65 per share. The gross proceeds from the 2024 Securities Purchase Agreement were $10.0 million and, after deducting offering expenses, the net proceeds were $9.9 million.

In January 2024, we were awarded the 2024 ASPR-BARDA Contract with a base and all options value of $9.3 million. Under the 2024 ASPR-BARDA Contract, we received an award to support clinical trial planning activities for a Phase 2b clinical trial that would compare our XBB vaccine candidate to an mRNA comparator to evaluate efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and adverse events. The 2024 ASPR-BARDA Contract originally had a period of performance term that was set to expire in July 2024, but we entered into an amendment in July 2024 that extended the period of performance expiration date into October 2024. BARDA and Vaxart are currently discussing contract closeout for the 2024 ASPR-BARDA Contract. As of March 31, 2025, we received approximately $9.3 million of cash payments under the 2024 ASPR-BARDA Contract.

In June 2024, we entered into an underwriting agreement with Oppenheimer & Co. Inc., relating to the issuance and sale by us in an underwritten registered direct offering (the “June 2024 Offering”) of 50,000,000 shares of our common stock at a price of $0.80 per share. The gross proceeds to us from such offering were $40.0 million, and after deducting the underwriting discounts and commissions and other offering expenses paid by us, the net proceeds were $37.5 million.

In June 2024, we entered into the 2024 ATI-RRPV Contract. Pursuant to the 2024 ATI-RRPV Contract, we may receive funding of up to $460.7 million to conduct a Phase 2b comparative study evaluating our oral pill COVID-19 vaccine candidate against an mRNA vaccine comparator approved by the FDA, manufacture a COVID-19 vaccine candidate targeting the KP.2 strain, and acquire an approved mRNA vaccine targeting the KP.2 strain. As of March 31, 2025, we have received $85.6 million of cash payments under the 2024 ATI-RRPV Contract. Subsequent to March 31, 2025, through the filing date of this Quarterly Report on Form 10-Q, we have received $9.2 million under the 2024 ATI-RRPV Contract.

As of March 31, 2025, we had approximately $41.9 million of cash, cash equivalents and short-term investments. Our cash, cash equivalents and investments are not sufficient to fund our planned operations for a period of 12 months from the date of issuance of this Quarterly Report. To continue operations, we expect that we will need to raise further capital, through the sale of additional securities or otherwise; however, adequate funding may not be available to us on acceptable terms, or at all, particularly in light of current economic uncertainty, high interest rates, rising inflation, tariffs, and the potential for local and/or global economic recession. Our future capital requirements and the adequacy of our available funds will depend on many factors, most notably our ability to successfully commercialize our products and services.

We may fund a significant portion of our ongoing operations through partnering and collaboration agreements which, while reducing our risks and extending our cash runway, will also reduce our share of eventual revenues, if any, from our vaccine candidates. We may be able to fund certain activities with assistance from government programs. The sale of additional equity would result in additional dilution to our stockholders. We may also fund our operations through debt financing, which would result in debt service obligations, and the instruments governing such debt could provide for operating and financing covenants that would restrict our operations. If we are unable to raise additional capital in sufficient amounts or on acceptable terms, we may be required to delay, limit, reduce, or terminate our product development or future commercialization efforts or grant rights to develop and market vaccine candidates that we would otherwise prefer to develop and market ourselves. Any of these actions could harm our business, results of operations and prospects.

Based on management’s current plan, we expect to have enough cash runway into the first quarter of 2026. If we are unable to raise additional capital in sufficient amounts or on acceptable terms, management’s plans include further reducing or delaying operating expenses. These conditions raise substantial doubt about our ability to continue as a going concern for a period of one year from the date of the issuance of these consolidated financial statements. The accompanying consolidated financial statements have been prepared assuming that we will continue as a going concern, which contemplates the realization of assets and the settlement of liabilities and commitments in the normal course of business.

Our future funding requirements will depend on many factors, including the following:

• the timing and costs of our planned preclinical studies for our product candidates;
• the timing and costs of our planned clinical trials of our product candidates;
• our manufacturing capabilities, including the availability of contract manufacturing organizations to supply our product candidates at reasonable cost;
• the amount and timing of royalties received on sales of Inavir;
• the number and characteristics of product candidates that we pursue;
• the outcome, timing and costs of seeking regulatory approvals;
• revenue received from commercial sales of our future products, which will be subject to receipt of regulatory approval;
• the terms and timing of any future collaborations, licensing, consulting or other arrangements that we may enter into;
• the amount and timing of any payments that may be required in connection with the licensing, filing, prosecution, maintenance, defense and enforcement of any patents or patent applications or other intellectual property rights;
• the current economic uncertainty, high interest rates, rising inflation, tariffs, and the potential for local and/or global economic recession;
• our ability to stay listed on The Nasdaq Capital Market; and
• the extent to which we in-license or acquire other products and technologies.

Cash Flows

The following table summarizes our cash flows for the periods indicated (in thousands):

Net Cash Used in Operating Activities

We experienced negative cash flow from operating activities for the three months ended March 31, 2025 and 2024, in the amounts of $9.6 million and $21.2 million, respectively. The cash used in operating activities in the three months ended March 31, 2025, was due to cash used to fund a net loss of $15.6 million, partially offset by a decrease in working capital of $3.4 million, and adjustments for net non-cash expenses related to depreciation and amortization, accretion of discount on investments, net, stock-based compensation, non-cash interest expense related to sale of future royalties and non-cash revenue related to sale of future royalties totaling $2.6 million. The cash used in operating activities in the three months ended March 31, 2024, was due to cash used to fund a net loss of $24.4 million and an increase in working capital of $0.8 million, partially offset by adjustments for net non-cash expenses related to depreciation and amortization, accretion of discount on investments, net, stock-based compensation, non-cash interest expense related to sale of future royalties and non-cash revenue related to sale of future royalties totaling $4.0 million.

Net Cash Provided by (Used in) Investing Activities

In the three months ended March 31, 2025, we received $13.4 million from maturities of investments, net of purchases, and used $0.1 million of cash to purchase property and equipment. In the three months ended March 31, 2024, we used $4.9 million to purchase investments, net of maturities, and used $0.1 million to purchase property and equipment.

Net Cash (Used in) Provided by Financing Activities

In the three months ended March 31, 2025, we used $0.2 million to acquire common stock to settle employee tax withholding liabilities. In the three months ended March 31, 2024, we received net proceeds of $8.4 million from the sale of our common stock under the September 2021 ATM and net proceeds of $9.9 million from the sale of our common stock under the 2024 Securities Purchase Agreement, partially offset by $0.2 million from common stock acquired to settle employee tax withholding liabilities.

Contractual Obligations and Commercial Commitments

We have the following contractual obligations and commercial commitments as of March 31, 2025 (in thousands):

Long Term Debt, HCRP. Under an agreement executed in 2016, during the first royalty interest period of April 1, 2016 through March 31, 2025, we are obligated to pay HCRP the first $3.0 million and any cumulative remaining shortfall amount plus 15% of the next $1.0 million in royalties earned in each year commencing on April 1, with any excess revenue being retained by us. Further, during the second royalty interest period beginning April 1, 2025 and ending on December 24, 2029, HCRP is entitled to the first $2.7 million and any cumulative remaining shortfall amount plus 15% of the next $1.0 million in royalties, with any excess revenue being retained by us. See Note 6 to the Condensed Consolidated Financial Statements in Part I, Item 1 for further details.

Operating leases. Operating lease amounts include future minimum lease payments under all our non-cancellable operating leases with an initial term in excess of one year.

Purchase obligations. The amounts include an estimate of all open purchase orders and contractual obligations in the ordinary course of business, including commitments with contract manufacturers and suppliers for which we have not received the goods or services. We consider all open purchase orders, which are generally enforceable and legally binding, to be commitments, although the terms may afford us the option to cancel based on our business needs prior to the delivery of goods or performance of services.

Critical Accounting Policies and Estimates

Our management’s discussion and analysis of financial condition and results of operations is based on our condensed consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States. The preparation of these consolidated financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities and expenses. On an ongoing basis, we evaluate these estimates and judgments. We base our estimates on historical experience and on various assumptions that we believe to be reasonable under the circumstances. These estimates and assumptions form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources. Actual results may differ materially from these estimates. We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates.

Accrued Research and Development Expenses

We record accrued expenses for estimated costs of research and development activities conducted by third-party service providers, which include the conduct of preclinical studies and clinical trials, and contract manufacturing activities. We record the estimated costs of research and development activities based upon the estimated amount of services provided and include the costs incurred but not yet invoiced within other accrued liabilities in the condensed consolidated balance sheets and within research and development expense in the condensed consolidated statements of operations and comprehensive loss. These costs can be a significant component of our research and development expenses.

We estimate the amount of work completed through discussions with internal personnel and external service providers as to the progress or stage of completion of the services and the agreed-upon fee to be paid for such services. We make significant judgments and estimates in determining the accrued balance in each reporting period. As actual costs become known, we adjust our accrued estimates.

Intangible Assets

Intangible assets comprise developed technology and intellectual property. Intangible assets are carried at cost less accumulated amortization. Amortization is computed using the straight-line method over useful life of 11.75 years for developed technology and 20 years for intellectual property. The fair value as of March 31, 2025 is being amortized on a straight-line basis over the remaining period of 4.6 years.

Revenue from Government Contracts

Under firm fixed-price milestone contracts, we recognize the firm fixed-price revenue as the milestones are substantially complete and the firm fixed-price for the milestone is earned (“firm fixed-price milestone”). Cash received in advance of the completion of a firm fixed-price milestone will be recorded as deferred revenue until the milestone has been substantially completed and earned. Under cost reimbursable contracts, we recognize revenue as allowable costs are incurred and the fixed fee is earned (“cost-plus-fixed-fee”). Reimbursable costs under the contract primarily include direct labor, subcontract costs, materials, equipment, travel, and approved overhead and indirect costs. Fixed fees under cost reimbursable contracts are earned in proportion to the allowable costs incurred in performance of the work relative to total estimated contract costs, with such costs incurred representing a reasonable measurement of the proportional performance of the work completed.

Payments to us under cost reimbursable contracts are provisional payments subject to adjustment upon annual audit by the government. Management believes that revenue for periods not yet audited has been recorded in amounts that are expected to be realized upon final audit and settlement. When the final determination of the allowable costs for any year has been made, revenue and billings may be adjusted accordingly in the period that the adjustment is known.

Stock-Based Compensation

We measure the fair value of all stock option awards to employees, non-executive directors and consultants on the grant date, and record the fair value of these awards, net of estimated forfeitures, as compensation expense over the service period. The fair value of options is estimated using the Black-Scholes valuation model and the expense recorded is affected by subjective assumptions regarding a number of variables, as follows:

Expected term – This represents the period that our stock-based awards granted are expected to be outstanding and is determined using the simplified method (the arithmetic average of its original contractual term and its average vesting term). We have very limited historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for our stock-based awards. Based on the weighted average applied to options awarded in the three months ended March 31, 2025, a notional 10% decrease in expected term would have reduced the fair value and the related compensation expense by approximately 2.2%.

Expected volatility – This is a measure of the amount by which our common stock price has fluctuated or is expected to fluctuate. Since the beginning of 2020, we have measured volatility based on the historical volatility of our own stock over the retrospective period corresponding to the expected term of the options on the measurement date. Based on the weighted average applied to options awarded in the three months ended March 31, 2025, a notional 10% decrease in expected volatility (from 126.5% to 113.8%) would have reduced the fair value and the related compensation expense by approximately 4.1%.

Risk-free interest rate – This is based on the U.S. Treasury yield curve on the measurement date corresponding with the expected term of the stock-based awards.

Expected dividend – We have not made any dividend payments and do not plan to pay dividends in the foreseeable future. Therefore, we use an expected dividend yield of zero.

Forfeiture rate – This is a measure of the number of awards that are expected to not vest and is reassessed quarterly. An increase in the estimated forfeiture rate will cause a small decrease to the related compensation expense early in the service period, but since the final expense recorded for each award is the number of options vested times their grant date fair value, it has no impact on the total expense recorded.

Recent Accounting Pronouncements

See the “Recent Accounting Pronouncements” in Note 2 to the Condensed Consolidated Financial Statements in Part I, Item 1 for information related to the issuance of new accounting standards to date. We are currently assessing the impact those new standards will have on the consolidated financial statements.

Interest Rate Sensitivity

Our exposure to market risk for changes in interest rates relates primarily to our investments in marketable debt securities. The primary objective of our investment activities is to preserve principal, maintain liquidity that is sufficient to meet cash needs and maximize total return without significantly increasing risk. To achieve this goal, we maintain our excess cash and cash equivalents in money market funds and marketable debt securities. We do not enter into investments for trading or speculative purposes and we hold no equity securities. We presently have no borrowings or lines of credit.

Specifically, as of March 31, 2025, we had cash, cash equivalents and short-term investments of approximately $41.9 million, which consist of primarily bank deposits, money market funds and U.S. government securities. All of our investments must satisfy high credit rating requirements at the time of purchase. Such interest-earning instruments carry a degree of interest rate risk, however, because our investments are rated highly and mostly short-term, we believe that our exposure to risk of loss due to interest rate changes is not significant.

Exchange Rate Sensitivity

Our royalty revenue, which is calculated in U.S. dollars, is based on sales in Japanese yen, so a 1% increase in the strength of the U.S. dollar against the yen would lead to a 1% reduction in royalty revenue and related accounts receivable. All our other revenue and substantially all of our expenses, assets and liabilities are denominated in U.S. dollars and, as a result, we have not experienced significant foreign exchange gains or losses recently and do not anticipate that foreign exchange gains or losses will be significant in the near future.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our principal executive officer and principal accounting and financial officer, has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended) as of the end of the period covered by this Quarterly Report on Form 10-Q. Based on such evaluation, our management has concluded that our disclosure controls and procedures were effective at a reasonable assurance level as of March 31, 2025.

Changes in Internal Control over Financial Reporting

There was no material change in our internal control over financial reporting that occurred during the quarter ended March 31, 2025, that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Controls

Our management, including our principal executive officer and principal accounting and financial officer, does not expect that our disclosure controls and procedures or our internal controls will prevent all error and all fraud. A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs. Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, within Vaxart have been detected.

You should consider the risks and uncertainties described under Item 1A of Part I of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, which we filed with the Securities and Exchange Commission on March 20, 2025, together with all other information contained or incorporated by reference in this Quarterly Report on Form 10-Q, when evaluating our business and our prospects. There are no material changes to the risk factors set forth in Part I, Item 1A, in our Annual Report on Form 10-K for the year ended December 31, 2024, except as described below.

A significant portion of the funding to further develop our COVID-19 vaccine candidate is currently expected to come from HHS BARDA funds. If HHS BARDA were to eliminate, reduce, delay, or object to funding available to us under the 2024 ATI-RRPV Contract, this could have a significant, negative impact on our revenues and cash flows, and we may be forced to suspend or terminate the continued development of the product candidate or obtain alternative sources of funding.

In June 2024, we entered into the 2024 ATI-RRPV Contract with ATI, the Rapid Response Partnership Vehicle’s Consortium Management Firm funded by HHS BARDA. The 2024 ATI-RRPV Contract, as modified and amended to date, provides for a funding ceiling of approximately $460.7 million. In February 2025, we entered into Modification No. 5 to the 2024 ATI-RRPV Contract. Modification No. 5 increased the total amount of funding available for payment to approximately $240.1 million.

We anticipate that a significant portion of the funding to further develop our COVID-19 vaccine candidate will come from the remaining amounts to be received under the 2024 ATI-RRPV Contract. The 2024 ATI-RRPV Contract provides that the government has the right to determine whether to fund the continued performance of the study after the initial funding. In February 2025, we received written notification directing the Company to stop work on the 2024 ATI-RRPV Contract, with the exception that we could continue effort associated with the per protocol follow-up for the 400-person cohort. The stop work order was in effect for a period of 90 days and, that within a period of 90 days, ATI, as directed by the U.S. Government, will either cancel the stop work order, extend the stop work, or terminate the work covered by the 2024 ATI-RRPV Contract. Subsequently, in April 2025, the Company received written notification from ATI in the form of the Lift Notice that the stop work order had been lifted and that the Company may resume incurring costs, participating in meetings, and communicating with the Government and ATI concerning the project award. The Lift Notice required further discussion between the Company and HHS BARDA regarding costs, timelines, and regulatory pathway agreement. The Company intends to continue discussions with HHS BARDA regarding the plan for dosing participants. The Company has not yet received approval to commence dosing.

The stop work order had the effect of reducing the Company's revenues but also lowering its expenses during the relevant time period. Even if we were to continue receiving funds under the 2024 ATI-RRPV Contract or were approved to commence dosing, the terms of the grant may unfavorably change or the amount of funding may decrease. If the 2024 ATI-RRPV Contract is terminated or further suspended, or if there is any government decision not to continue funding or reduction or further delay in funding under the 2024 ATI-RRPV Contract, our revenues and cash flows would be significantly and negatively impacted and we may be forced to seek alternative sources of funding, which may not be available on non-dilutive terms, terms favorable to us, or at all.