Vaxart, Inc.

Previous wording

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 Form10-K filed with the SEC on March 13, 2026. 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.

Current wording

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our unaudited 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 Form10-K filed with the SEC on March 13, 2026. 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.

Previous wording

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 for a Phase 2b clinical study. This Phase 2b clinical study is designed as 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 2024 ATI-RRPV Contract initially authorized to receive total funding of up to $460.7 million to conduct this Phase 2b study, manufacture a COVID-19 vaccine candidate, and acquire an approved mRNA vaccine targeting a homologous strain.

Current wording

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 for a Phase 2b clinical study. This Phase 2b clinical study is designed as 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 2024 ATI-RRPV Contract initially authorized us to receive total funding of up to $460.7 million to conduct this Phase 2b study, manufacture a COVID-19 vaccine candidate, and acquire an approved mRNA vaccine targeting a homologous strain.

Previous wording

In connection with these contract developments, the Company has received funding through a series of contract modifications tied to authorized milestones. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which adjusted the total amount of authorized funding under the 2024 ATI-RRPV contract to approximately $344.8 million, including $67.9 million of firm fixed price amounts and the remaining amount for reimbursement of costs incurred in trial preparation and execution activities. The funding available for payment increased from $316.0 million to $331.0 million (an increase of $15.0 million) as compared to the previous Modification No. 6 signed March 10, 2026. The June 2026 total authorized funding reduction from $460.7 million to $344.8 million in the 2024 ATI-RRPV Contract reflected reduction in scope of work and corresponding reduction in funding that resulted from previously issued stop work orders that halted enrollment and therefore reduced the size of the study.

Current wording

In connection with these contract developments, the Company has received funding through a series of contract modifications tied to authorized milestones. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which adjusted the total amount of authorized funding under the 2024 ATI-RRPV contract to approximately $344.8 million, including $67.9 million of firm fixed price amounts and the remaining amount for reimbursement of costs incurred in trial preparation and execution activities. The funding available for payment increased from $331.0 million to $336.4 million (an increase of $5.4 million) for the quarter ended September 30, 2026. The 2024 ATI-RRPV Contract further contemplates additional funding available for payment up to $8.4 million if the Company and HHS BARDA decide to continue with the Phase 2b comparative study. The June 2026 total authorized funding reduction from $460.7 million to $344.8 million in the 2024 ATI-RRPV Contract reflected reduction in scope of work and corresponding reduction in funding that resulted from previously issued stop work orders that halted enrollment and therefore reduced the size of the study.

Previous wording

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.

Current wording

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 at that time, reduced clinical disease by 27%. Our tablet vaccine candidate also showed a favorable safety profile, indistinguishable from placebo.

Previous wording

***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.

Current wording

***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 have been published in a scientific paper (Frontiers in Immunology, 2026).

Previous wording

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. No revenue from government contracts was recognized on the 2024 ASPR-BARDA Contract for the three months ended June 30, 2026 and 2025, based on the achievement of certain milestones under the 2024 ASPR-BARDA Contract.

Current wording

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. No revenue from government contracts was recognized on the 2024 ASPR-BARDA Contract for the three and nine months ended September 30, 2026 and $0.6 million was recognized for each of the three and nine months ended September 30, 2025 based on the achievement of certain milestones under the 2024 ASPR-BARDA Contract.

Previous wording

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 were to receive total 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. Funding has been released pursuant to authorized milestones delineated in a series of contract modifications. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which increased the total amount of funding available for payment under the 2024 ATI-RRPV Contract to approximately $331.0 million, an increase of approximately $15.0 million as compared to the approximately $316.0 million funding authorized for payment under Modification No. 6, dated March 10, 2026. The authorized total funding in Modification No. 7 was reduced at the same time by $115.9 million to $344.8 million as compared to $460.7 million previously, to reflect the reduced scope of work from the previously issued stop work orders that halted enrollment and reduced the size of the study. Revenue from government contracts recognized on the 2024 ATI-RRPV Contract was $24.3 million and $39.7 million for the three months ended June 30, 2026 and 2025, respectively, based on costs incurred and the achievement of firm fixed-price milestones under the 2024 ATI-RRPV Contract. For further information about the August 5, 2025 stop work order relating to the 2024 ATI-RRPV Contract, see the section above titled “—Our Product Pipeline” in the “Coronavirus Vaccine” discussion.

Current wording

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 were to receive total 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. Funding has been released pursuant to authorized milestones delineated in a series of contract modifications. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which adjusted the total amount of authorized funding under the 2024 ATI-RRPV contract to approximately $344.8 million, including $67.9 million of firm fixed price amounts and the remaining amount for reimbursement of costs incurred in trial preparation and execution activities. The funding available for payment increased from $331.0 million to $336.4 million (an increase of $5.4 million) for the quarter ended September 30, 2026. The 2024 ATI-RRPV Contract further contemplates additional funding available for payment up to $8.4 million if the Company and HHS BARDA decide to continue with the Phase 2b comparative study. The authorized total funding in Modification No. 7 was reduced at the same time by $115.9 million to $344.8 million as compared to $460.7 million previously, to reflect the reduced scope of work from the previously issued stop work orders that halted enrollment and reduced the size of the study. Revenue from government contracts recognized on the 2024 ATI-RRPV Contract was $7.5 million and $71.8 million for the three months ended September 30, 2026 and 2025, respectively, based on costs incurred under the 2024 ATI-RRPV Contract. For further information about the August 5, 2025 stop work order relating to the 2024 ATI-RRPV Contract, see the section above titled “—Our Product Pipeline” in the “Coronavirus Vaccine” discussion.

Previous wording

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 and six months ended June 30, 2026 and 2025 (in thousands):

Current wording

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 and nine months ended September 30, 2026 and 2025 (in thousands):

Previous wording

The following table presents period-over-period changes in selected items in the condensed consolidated statements of operations and comprehensive loss for the three and six months ended June 30, 2026 and 2025 (in thousands, except percentages):

Current wording

The following table presents period-over-period changes in selected items in the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2026 and 2025 (in thousands, except percentages):

Previous wording

The following table summarizes the period-over-period changes in our revenues for the three and six months ended June 30, 2026 and 2025 (in thousands, except percentages):

Current wording

The following table summarizes the period-over-period changes in our revenues for the three and nine months ended September 30, 2026 and 2025 (in thousands, except percentages):

Previous wording

For the three and six months ended June 30, 2026 and 2025, non-cash royalty revenue related to sale of future royalties from Daiichi Sankyo was $11,000 and zero, and $53,000 and $1.6 million, respectively. We continue to have non-cash royalty revenue as all royalties received for the three and six months ended June 30, 2026 and 2025 were required to be paid to HCRP.

Current wording

For the three and nine months ended September 30, 2026 and 2025, non-cash royalty revenue related to sale of future royalties from Daiichi Sankyo was $154,000 and zero, and $0.2 million and $1.6 million, respectively. We continue to have non-cash royalty revenue as all royalties received for the three and nine months ended September 30, 2026 and 2025 were required to be paid to HCRP.

Previous wording

For the three and six months ended June 30, 2026 and 2025, revenue from government contracts was $24.3 million and $39.7 million, and $60.6 million and $59.0 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. No revenue was recognized under the 2024 ASPR-BARDA Contract for the three and six months ended June 30, 2026 and 2025, respectively. Revenue from the ATI-RRPV Contract was $24.3 million and $39.7 million for the three months ended June 30, 2026 and 2025, respectively, and $60.6 million and $59.0 million for the six months ended June 30, 2026 and 2025, respectively.

Current wording

For the three and nine months ended September 30, 2026 and 2025, revenue from government contracts was $7.5 million and $72.4 million, and $68.2 million and $131.4 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. No revenue was recognized under the 2024 ASPR-BARDA Contract for the three and nine months ended September 30, 2026 . Revenue from the 2024 ASPR-BARDA Contract was $0.6 million for both the three and nine months ended September 30, 2025, respectively. Revenue from the ATI-RRPV Contract was $7.5 million and $71.8 million for the three months ended September 30, 2026 and 2025, respectively, and $68.2 million and $130.8 million for the nine months ended September 30, 2026 and 2025, respectively.

Previous wording

For the three and six months ended June 30, 2026 and 2025, collaboration revenue was $2.9 million and zero, and $5.7 million and zero, respectively. The license and collaboration revenue derives from the 2025 License and Collaboration Agreement signed in November 2025. Revenue recognized in 2026 primarily relates to the portion of the upfront consideration allocated to development activities performed during the period.

Current wording

For the three and nine months ended September 30, 2026 and 2025, collaboration revenue was $2.9 million and zero, and $8.7 million and zero, respectively. The license and collaboration revenue derives from the 2025 License and Collaboration Agreement signed in November 2025. Revenue recognized in 2026 primarily relates to the portion of the upfront consideration allocated to development activities performed during the period.

Previous wording

The following table summarizes the period-over-period changes in our operating expenses for the three and six months ended June 30, 2026 and 2025 (in thousands, except percentages):

Current wording

The following table summarizes the period-over-period changes in our operating expenses for the three and nine months ended September 30, 2026 and 2025 (in thousands, except percentages):

Previous wording

For the three months ended June 30, 2026, research and development expenses decreased by $16.0 million, or 32%, compared to the three months ended June 30, 2025. The net decrease was primarily due to a decrease in clinical trial expenses related to our COVID-19 vaccine candidate, personnel costs, facilities costs, and preclinical and manufacturing costs.

Current wording

For the three months ended September 30, 2026, research and development expenses decreased by $53.1 million, or 70%, compared to the three months ended September 30, 2025. The net decrease was primarily due to a decrease in clinical trial expenses related to our COVID-19 and norovirus vaccine candidates, personnel costs, facilities and manufacturing costs.

Previous wording

For the six months ended June 30, 2026, research and development expenses decreased by $17.3 million, or 22%, compared to the six months ended June 30, 2025. The net decrease was primarily due to a decrease in clinical trial expenses related to our COVID-19 vaccine candidate, personnel costs, preclinical and manufacturing costs, and facilities costs.

Current wording

For the nine months ended September 30, 2026, research and development expenses decreased by $70.4 million, or 45% compared to the nine months ended September 30, 2025. The net decrease was primarily due to a decrease in clinical trial expenses related to our COVID-19 and norovirus vaccine candidates, personnel costs, facilities and manufacturing costs.

Previous wording

For the six months ended June 30, 2026, general and administrative expenses increased by $1.6 million, or 16%, compared to the six months ended June 30, 2025. The net increase was primarily due to an increase in professional and legal fees, partially offset by a decrease in personnel costs.

Current wording

For the three months ended September 30, 2026, general and administrative expenses increased by $0.8 million, or 19%, compared to the three months ended September 30, 2025. The net increase was primarily due to an increase in professional and legal fees.

Previous wording

For the three months ended June 30, 2026, general and administrative expenses increased by $2.0 million, or 44%, compared to the three months ended June 30, 2025. The net increase was primarily due to an increase in professional and legal fees partially offset by a decrease in personnel costs.

Current wording

For the nine months ended September 30, 2026, general and administrative expenses increased by $2.4 million, or 17%, compared to the nine months ended September 30, 2025. The net increase was primarily due to an increase in professional and legal fees, partially offset by a decrease in personnel and facilities costs.

Previous wording

The following table summarizes the period-over-period changes in our non-operating income for the three and six months ended June 30, 2026 and 2025 (in thousands, except percentages):

Current wording

The following table summarizes the period-over-period changes in our non-operating expense for the three and nine months ended September 30, 2026 and 2025 (in thousands, except percentages):

Previous wording

For thethree months ended June 30, 2026, we recorded interest income of $0.6 million, an 86% increase from the $0.3 million interest income recorded in thethree months ended June 30, 2025. For thesix months ended June 30, 2026, we recorded interest income of $1.1 million, a 51% increase from the $0.7 million interest income recorded in thesix months ended June 30, 2025. The increase is due to both higher average cash, cash equivalents and short-term investment balances held and more favorable interest rates available.

Current wording

For thethree months ended September 30, 2026, we recorded interest income of $0.5 million, a 79% increase from the $0.3 million interest income recorded in thethree months ended September 30, 2025. For thenine months ended September 30, 2026, we recorded interest income of $1.7 million, a 59% increase from the $1.0 million interest income recorded in thenine months ended September 30, 2025. The increase is due to both higher average cash, cash equivalents, and short-term investment balances held and more favorable interest rates available.

Previous wording

Non-cash interest expense related to sale of future royalties representing imputed interest on the unamortized portion of the sale of future royalties liability, was $0.5 million and $0.7 million for the three months ended June 30, 2026 and 2025 and $1.0 million and $1.7 million for the six months ended June 30, 2026 and 2025. The decrease was due to a decrease in non-cash royalty revenue payable to HCRP.

Current wording

Non-cash interest expense related to sale of future royalties representing imputed interest on the unamortized portion of the sale of future royalties liability, was $0.6 million for both the three months ended September 30, 2026 and 2025 and $1.7 million and $2.3 million for the nine months ended September 30, 2026 and 2025. The decrease was due to a decrease in non-cash royalty revenue payable to HCRP.

Previous wording

Other expense, net, was $0.3 million and $1,000 for the three months ended June 30, 2026 and 2025, and $0.3 million and $2,000 for the six months ended June 30, 2026 and 2025. The other expense increase was due to a $0.3 million non-cash loss recorded as related to the issuance of common stock for commitment shares according to the terms of the April 2026 ELOC.

Current wording

Other expense, net, was $8,000 and $7,000 for the three months ended September 30, 2026 and 2025, and $0.4 million and $9,000 for the nine months ended September 30, 2026 and 2025. The other expense increase was due to a $0.3 million non-cash loss recorded as related to the issuance of common stock for commitment shares according to the terms of the April 2026 ELOC.

Previous wording

The following table summarizes the period-over-period changes in our provision for income taxes for the three and six months ended June 30, 2026 and 2025 (in thousands, except percentages):

Current wording

The following table summarizes the period-over-period changes in our provision for income taxes for the three and nine months ended September 30, 2026 and 2025 (in thousands, except percentages):

Previous wording

The provision for income taxes was $29,000 and $20,000 for the three months ended June 30, 2026 and 2025, respectively and $58,000 and $115,000 for the six months ended June 30, 2026 and 2025, respectively. The tax charge relates to foreign tax expense attributable 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 foreign withholding tax expense recorded is directly proportional to Inavir royalties, including the portion that we pass through to HCRP.

Current wording

The provision for income taxes was $0.3 million and $17,000 for the three months ended September 30, 2026 and 2025, respectively and $0.4 million and $132,000 for the nine months ended September 30, 2026 and 2025, respectively. The tax charge relates to foreign tax expense attributable 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 foreign withholding tax expense recorded is directly proportional to Inavir royalties, including the portion that we pass through to HCRP. State income taxes increase of $0.3 million for the three and nine months ended September 30, 2026 is due to state income tax update in response to July 2025 Federal income tax change to research and development capitalization rules.

Previous wording

In June 2024, we entered into the 2024 ATI-RRPV Contract. Pursuant to the 2024 ATI-RRPV Contract, we were authorized to receive total 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 U.S. Food and Drug Administration, manufacture a COVID-19 vaccine candidate targeting the KP.2 strain, and acquire an approved mRNA vaccine targeting the KP.2 strain. As of June 30, 2026, we have received $253.8 million of cash payments under the 2024 ATI-RRPV Contract. Subsequent to June 30, 2026, through the filing date of this Quarterly Report on Form 10-Q, we have received $12.8 million under the 2024 ATI-RRPV Contract. On August 5, 2025, the Company received written notification from ATI in the form of a stop work order directing the Company to stop work on screening and enrollment for the COVID-19 Phase 2b trial under the 2024 ATI-RRPV Contract as of the notification date. On October 8, 2025, the Company received a follow-up notice from ATI, which indicated that BARDA intends to conclusively exclude work subject to the foregoing stop work order from the 2024 ATI-RRPV Contract. The Company was, however, authorized to continue efforts associated with the per protocol follow-up of all participants dosed as of the notification date in the study under the terms of the 2024 ATI-RRPV Contract. When the Company received the August notification, we had enrolled approximately half of the targeted number of participants for the study. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which adjusted the total amount of authorized funding under the 2024 ATI-RRPV Contract down to approximately $344.8 million, including $67.9 million of firm fixed price amounts and the remaining amount for reimbursement of costs incurred in trial preparation and execution activities. The funding available for payment increased from $316.0 million to $331.0 million (an increase of $15.0 million) as compared to the previous Modification No. 6 signed March 10, 2026. The 2024 ATI-RRPV Contract further contemplates additional funding up to $13.8 million if the Company and HHS BARDA decide to continue with the Phase 2b comparative study. The June 2026 reduction from $460.7 million to $344.8 million in the 2024 ATI-RRPV Contract reflected reduction in scope of work and corresponding reduction in funding that resulted from previously issued stop work orders that halted enrollment and therefore reduced the size of the study.

Current wording

In June 2024, we entered into the 2024 ATI-RRPV Contract. Pursuant to the 2024 ATI-RRPV Contract, we were authorized to receive total 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 U.S. Food and Drug Administration, manufacture a COVID-19 vaccine candidate targeting the KP.2 strain, and acquire an approved mRNA vaccine targeting the KP.2 strain. As of September 30, 2026, we have received $278.0 million of cash payments under the 2024 ATI-RRPV Contract. Subsequent to September 30, 2026, through the filing date of this Quarterly Report on Form 10-Q, we have received $20.9 million under the 2024 ATI-RRPV Contract. On August 5, 2025, the Company received written notification from ATI in the form of a stop work order directing the Company to stop work on screening and enrollment for the COVID-19 Phase 2b trial under the 2024 ATI-RRPV Contract as of the notification date. On October 8, 2025, the Company received a follow-up notice from ATI, which indicated that BARDA intends to conclusively exclude work subject to the foregoing stop work order from the 2024 ATI-RRPV Contract. The Company was, however, authorized to continue efforts associated with the per protocol follow-up of all participants dosed as of the notification date in the study under the terms of the 2024 ATI-RRPV Contract. When the Company received the August notification, we had enrolled approximately half of the targeted number of participants for the study. The Company most recently signed Modification No. 7 to the 2024 ATI-RRPV Contract, dated June 22, 2026, which adjusted the total amount of authorized funding under the 2024 ATI-RRPV Contract down to approximately $344.8 million, including $67.9 million of firm fixed price amounts and the remaining amount for reimbursement of costs incurred in trial preparation and execution activities. The funding available for payment increased from $331.0 million to $336.4 million (an increase of $5.4 million) for the quarter ended September 30, 2026. The 2024 ATI-RRPV Contract further contemplates additional funding available for payment up to $8.4 million if the Company and HHS BARDA decide to continue with the Phase 2b comparative study. The June 2026 reduction from $460.7 million to $344.8 million in the 2024 ATI-RRPV Contract reflected reduction in scope of work and corresponding reduction in funding that resulted from previously issued stop work orders that halted enrollment and therefore reduced the size of the study.

Previous wording

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. During the three months ended June 30, 2026, no shares were issued and sold under the March 2025 ATM. As of June 30, 2026, approximately $48.4 million of our common stock remained available for issuance and sale pursuant to the March 2025 ATM. However, we are unable to leverage the ATM at this time because our common stock has been delisted from trading on The Nasdaq Capital Market.

Current wording

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. 333-295086), as previously filed with the U.S. Securities and Exchange Commission (the “SEC”). The Company filed a prospectus supplement, dated May 4, 2026 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. During the three months ended September 30, 2026, no shares were issued and sold under the March 2025 ATM. As of September 30, 2026, approximately $48.4 million of our common stock remained available for issuance and sale pursuant to the March 2025 ATM. However, our ability to make sales under the March 2025 ATM is limited because our common stock is no longer listed on a national securities exchange and offers and sales of our common stock must comply with applicable state securities laws.

Previous wording

Effective July 8, 2025, Nasdaq suspended trading in our common stock and the Company was formally delisted from Nasdaq effective December 1, 2025. Our common stock has been quoted on the OTCQX under the ticker symbol “VXRT” since the stock was suspended from trading on Nasdaq on July 8, 2025. The National Securities Markets Improvement Act of 1996 prevents or preempts the states from regulating the sale of certain securities, which are referred to as “covered securities.” As Nasdaq has officially delisted our securities, our securities are not covered securities since OTCQX-traded securities are not considered covered securities, and we will need to follow each state’s blue sky laws for offers and sales of our securities made to residents of that state. This state-level regulation introduces additional compliance requirements for brokers to consider when trading in our securities and will further negatively impact any trading liquidity in our securities.

Current wording

Effective July 8, 2025, Nasdaq suspended trading in our common stock and the Company was formally delisted from Nasdaq effective December 1, 2025. Our common stock has been quoted on the OTCQX Best Market (“OTCQX”) under the ticker symbol “VXRT” since the stock was suspended from trading on Nasdaq on July 8, 2025. The National Securities Markets Improvement Act of 1996 prevents or preempts the states from regulating the sale of certain securities, which are referred to as “covered securities.” Because Nasdaq has officially delisted our securities, and securities traded on OTCQX are not considered covered securities, offers and sales of our securities to residents of each state must comply with that state’s blue sky laws. This state-level regulation introduces additional compliance requirements for brokers to consider when trading in our securities and will further negatively impact any trading liquidity in our securities.

Previous wording

On November 4, 2025, the Company entered into (i) an Exclusive License and Collaboration Agreement (the “License and Collaboration Agreement”) with Dynavax Technologies Corporation (“Dynavax”) relating to the Company’s investigational oral vaccine candidate for COVID-19 based on its proprietary oral delivery platform and (ii) a Securities Purchase Agreement with Dynavax for the sale of the Company’s common stock. Pursuant to the License and Collaboration Agreement, the Company granted Dynavax an exclusive, worldwide license to develop and commercialize the Company’s oral pill COVID-19 vaccine candidate for SARS-CoV-2, SARS coronavirus, or MERS coronavirus, including COVID-19 and all variants thereof. Under the terms of the License and Collaboration Agreement, Dynavax paid the Company an upfront license fee of $25.0 million and purchased $5.0 million of the Company’s common stock pursuant to the Securities Purchase Agreement. The License and Collaboration Agreement includes a collaboration component designed to facilitate the efficient development, regulatory approval, and commercialization of products within the defined field of use, as described in greater detail in the Current Report on Form 8-K filed by the Company with the SEC on November 5, 2025. Pursuant to the Securities Purchase Agreement, the Company sold and issued 11,111,111 shares of common stock at a per share purchase price of $0.45 under the Company’s shelf registration statement on Form S-3, including the prospectus dated May 5, 2025 contained therein, and the prospectus supplement dated November 4, 2025.

Current wording

On November 4, 2025, the Company entered into (i) an Exclusive License and Collaboration Agreement (the “License and Collaboration Agreement”) with Dynavax relating to the Company’s investigational oral vaccine candidate for COVID-19 based on its proprietary oral delivery platform and (ii) a Securities Purchase Agreement with Dynavax for the sale of the Company’s common stock. Pursuant to the License and Collaboration Agreement, the Company granted Dynavax an exclusive, worldwide license to develop and commercialize the Company’s oral pill COVID-19 vaccine candidate for SARS-CoV-2, SARS coronavirus, or MERS coronavirus, including COVID-19 and all variants thereof. Under the terms of the License and Collaboration Agreement, Dynavax paid the Company an upfront license fee of $25.0 million and purchased $5.0 million of the Company’s common stock pursuant to the Securities Purchase Agreement. The License and Collaboration Agreement includes a collaboration component designed to facilitate the efficient development, regulatory approval, and commercialization of products within the defined field of use, as described in greater detail in the Current Report on Form 8-K filed by the Company with the SEC on November 5, 2025. Pursuant to the Securities Purchase Agreement, the Company sold and issued 11,111,111 shares of common stock at a per share purchase price of $0.45 under the Company’s shelf registration statement on Form S-3, including the prospectus dated May 5, 2025 contained therein, and the prospectus supplement dated November 4, 2025. Dynavax was subsequently acquired by Sanofi and currently operates as an indirect wholly owned subsidiary of Sanofi.

Previous wording

In April 2026, we entered into a purchase agreement (the “April 2026 ELOC”) with Lincoln Park Capital Fund, LLC (“LPC”), pursuant to which the Company may sell, from time to time, up to $25.0 million (the “Commitment Amount”) of registered shares of its common stock over a 24-month period, subject to certain limitations and conditions. In May 2026, the Company filed a registration statement with the SEC covering the resale by LPC of the Purchase Shares that have been and may be issued to LPC under the April 2026 ELOC. As of June 30, 2026, 75,000 shares were issued and sold under the April 2026 ELOC for gross proceeds of $44,000. As of June 30, 2026, approximately $25 million of the Commitment Amount remained available for issuance and sale pursuant to the April 2026 ELOC.

Current wording

In April 2026, we entered into a purchase agreement (the “April 2026 ELOC”) with Lincoln Park Capital Fund, LLC (“LPC”), pursuant to which the Company may sell, from time to time, up to $25.0 million (the “Commitment Amount”) of shares of its common stock over a 24-month period, subject to certain limitations and conditions. In May 2026, the Company filed a registration statement with the SEC covering the resale by LPC of the Purchase Shares that have been and may be issued to LPC under the April 2026 ELOC. The Purchase Shares are sold to LPC in reliance on the exemption from registration provided by Section 4(a)(2) of the Securities Act, and LPC’s resale of the Purchase Shares is registered under our registration statement on Form S-1 (Registration Statement No. 333-295737), which was declared effective by the SEC on May 18, 2026. As of September 30, 2026, 925,000 shares were issued and sold under the April 2026 ELOC for gross proceeds of $0.5 million. As of September 30, 2026 approximately $24.5 million of the Commitment Amount remained available for issuance and sale pursuant to the April 2026 ELOC.

Previous wording

As of June 30, 2026, we had approximately $64.0 million of cash, cash equivalents and short-term investments. Our cash, cash equivalents and investments are sufficient to fund our planned operations for at least the 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.

Current wording

As of September 30, 2026, we had approximately $65.5 million of cash, cash equivalents and short-term investments. Our cash, cash equivalents and investments are not sufficient to fund our planned operations for at least the 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.

Previous wording

Based on management’s current plan, we expect to have enough cash runway into the second quarter of 2027. 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.

Current wording

Based on management’s current plan, we expect to have enough cash runway into the second quarter of 2027. If the Company cannot raise sufficient additional capital on acceptable terms, management plans to further reduce or defer 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 unaudited condensed consolidated financial statements. The accompanying unaudited condensed 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.

Previous wording

For operating activities, we experienced positive cash flow of $0.7 million for the six months ended June 30, 2026 and a negative cash flow of $25.5 million for the six months ended June 30, 2025. The net cash provided by operating activities in the six months ended June 30, 2026, was due to an operating net loss of $8.3 million, offset by an increase in working capital of $3.3 million (consisting of a decrease in receivables from government contracts and prepaid expenses and partially offset by an increase in unbilled receivables from government contracts, accounts payable, deferred collaboration revenue and accrued labilities), and adjustments for non-cash expenses related to stock-based compensation of $2.8 million, depreciation and amortization of $1.9 million, and $1.0 million of non-cash interest expense related to sale of future royalties. The cash used in operating activities in the six months ended June 30, 2025, was due to cash used to fund a net loss of $30.6 million, partially offset by a decrease in working capital of $1.0 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 $6.0 million.

Current wording

For operating activities, we experienced positive cash flow of $2.2 million for the nine months ended September 30, 2026 and a negative cash flow of $22.9 million for the nine months ended September 30, 2025. The net cash provided by operating activities in the nine months ended September 30, 2026, was due to an operating net loss of $26.0 million, offset by an increase in working capital of $19.7 million (consisting of a decrease in accrued liabilities, deferred government revenue and partially offset by an increase in unbilled receivables from government contracts, prepaid expenses, accounts payable, accounts receivable and deferred collaboration revenue) and adjustments for non-cash expenses related to primarily stock-based compensation of $4.0 million, depreciation and amortization of $3.1 million, and $1.7 million of non-cash interest expense related to sale of future royalties. The cash used in operating activities in the nine months ended September 30, 2025, was due to cash used to fund a net loss of $38.7 million, partially offset by an increase in working capital of $5.1 million (consisting of an increase in accounts payable and clinical accruals and partially offset by an increase in receivables from government contracts), 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 $10.7 million.

Previous wording

In the six months ended June 30, 2026, we had $3.4 net cash used for investing activities. Net cash used resulted from $2.9 million of investments purchased, net of maturities, and used $0.5 million to purchase property and equipment, net of proceeds. In the six months ended June 30, 2025, we received $20.5 million from maturities of investments, net of purchases of investments.

Current wording

In the nine months ended September 30, 2026, we had $21.0 million net cash used for investing activities. Net cash used resulted from $20.2 million of investments purchased, net of maturities, and used $0.8 million to purchase property and equipment, net of proceeds. In the nine months ended September 30, 2025, we received $14.8 million from maturities of investments, net of purchases, and used $0.1 million to purchase property and equipment, net of proceeds.

Previous wording

In the six months ended June 30, 2026, we used $0.4 million to acquire common stock to settle employee tax withholding liabilities. In the six months ended June 30, 2025, we used approximately $0.2 million to acquire common stock to settle employee tax withholding liabilities.

Current wording

In the nine months ended September 30, 2026, we used $0.4 million to acquire common stock to settle employee tax withholding liabilities offset by $0.5 million of proceeds received from the issuance of common stock under the April 2026 ELOC, $0.2 million of proceeds from the issuance of treasury stock under the ESPP, $57,000 from the issuance of common stock upon the exercise of stock options and paid $0.2 million of issuance costs related to the April 2026 ELOC. In the nine months ended September 30, 2025, we used $0.2 million to acquire common stock to settle employee tax withholding liabilities, and received $79,000 of proceeds from issuance of treasury stock under the ESPP, and net proceeds of $53,000 from the sale of our common stock under the March 2025 ATM.

Previous wording

Purchase obligations. As of June 30, 2026, the Company had approximately $22.5 million of non-cancelable purchase commitments, principally for clinical services which are expected to be paid within the next year. Approximately $7.2 million of non-cancelable purchase commitments are attributable to third-party vendors that provides service as related to the ATI-RRPV Contract, that is reimbursable at approximately $7.7 million under a cost-plus-fixed-fees arrangement.

Current wording

Purchase obligations. As of September 30, 2026, the Company had approximately $9.4 million of non-cancelable purchase commitments, principally for clinical services which are expected to be paid within the next year. Approximately $0.3 million of non-cancelable purchase commitments are attributable to third-party vendors that provide services related to the 2024 ATI-RRPV Contract and are reimbursable at approximately $0.4 million under a cost-plus-fixed-fees arrangement.

Previous wording

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.

Current wording

Our management’s discussion and analysis of financial condition and results of operations is based on our unaudited condensed consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States. The preparation of these unaudited condensed 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.

Previous wording

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 June 30, 2026 is being amortized on a straight-line basis over the remaining period of 3.4 years and 1.5 years for developed technology and intellectual property, respectively.

Current wording

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 September 30, 2026 is being amortized on a straight-line basis over the remaining period of 3.1 years and 1.3 years for developed technology and intellectual property, respectively.

Previous wording

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 six months ended June 30, 2026, a notional 10% decrease in expected term would have reduced the fair value and the related compensation expense by approximately 2.3%.

Current wording

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 nine months ended September 30, 2026, a notional 10% decrease in expected term would have reduced the fair value and the related compensation expense by approximately 3.0%.

Previous wording

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 six months ended June 30, 2026, a notional 10% decrease in expected volatility (from 124.1% to 111.7%) would have reduced the fair value and the related compensation expense by approximately 4.3%.

Current wording

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 nine months ended September 30, 2026, a notional 10% decrease in expected volatility (from 104.2% to 93.8%) would have reduced the fair value and the related compensation expense by approximately 5.3%.