Vaxart, Inc.

NOTE5.**Revenue

Royalty Revenue Related to Sale of Future Royalties

The Company generates royalty revenue from the sale of Inavir in Japan, pursuant to a collaboration and license agreement that Aviragen entered into with Daiichi Sankyo Company, Limited (“Daiichi Sankyo”) in2009. In* September 2010,laninamivir octanoate was approved for sale by the Japanese Ministry of Health and Welfare for the treatment of influenza in adults and children, which Daiichi Sankyo markets as Inavir. Under the agreement, the Company currently receives a 4% royalty on net sales of Inavir in Japan. Based on information provided by Daiichi Sankyo, the Company's royalty revenue will cease with the expiration of the last patent related to Inavir in August 2036.The Company’s royalty revenue is seasonal, in line with the flu season, so the majority of the Company’s royalty revenue and non-cash royalty revenue related to the sale of future royalties are earned in thefirst* andfourth fiscal quarters. The royalty revenue related to Inavir recognized for thethree months ended* March 31, 2026and2025* was zero. The non-cash royalty revenue related to the sale of future royalties was $42,000 and $1.6 million for thethree months ended* March 31, 2026* and2025, respectively. Both royalty revenue and the non-cash royalty revenue related to the sale of future royalties are subject to a 5% withholding tax in Japan, for which $2,000 and $79,000 was included in income tax expense for thethree months ended* March 31, 2026* and2025, respectively, further detailed in Note6.

The Company recognized revenue from government contracts with HHS BARDA of $36.4 million and $19.3 million for thethree months ended* March 31, 2026and2025*, respectively, consisting of revenue from the2024 ASPR-BARDA Contract (as defined below) and the2024 ATI-RRPV Contract (as defined below) described in more detail below. Unbilled receivable from government contracts consists of government revenue from HHS BARDA, which was earned andnot yet billed. As of* March 31, 2026* and* December 31, 2025*, the amount of unbilled receivable was $50.4 million and $36.8 million, respectively, and deferred revenue was $23,000 and $68,000, respectively.

2024 ATI-RRPV Contract

In* June 2024,the Company 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, which was modified in thesecond half of2024 to increase funding and provide for the manufacturing of a vaccine candidate targeting theKP.2 strain and acquire an approved mRNA vaccine targeting theKP.2 strain. Pursuant to the2024 ATI-RRPV Contract, the Company was authorized to receive overall funding of up to $460.7 million to conduct a Phase2b comparative study evaluating the Company’s oral pill COVID-19 vaccine candidate against an mRNA vaccine comparator approved by the U.S. Food and Drug Administration (“FDA”). Funding has been released pursuant to authorized milestones delineated in a series of contract modifications. Pursuant to ModificationNo. 6 to the2024 ATI-RRPV Contract, dated* March 10, 2026 (the most recent contract modification), the total amount of funding available for payment under the2024* ATI-RRPV Contract is approximately $316.0 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 Company anticipates a further modification to the2024 ATI-RRPV Contract that will reflect the reduced 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.

The Company accounts for the2024 ATI-RRPV Contract under Accounting Standards Codification958-605 (“ASC958-605”) and recognizes revenue as the firm fixed-price milestone is earned and allowable cost-plus-fixed-fees are incurred. Reimbursable costs under the2024 ATI-RRPV Contract primarily include direct labor, subcontract costs, materials, travel, and approved overhead and indirect costs. The2024 ATI-RRPV Contract contains terms and conditions that are customary for contracts with HHS BARDA of this nature, including the U.S. government having the right to terminate the contract for convenience or to terminate for default if the Company fails to meet its obligations as set forth in the statement of work. Revenue from government contracts recognized on the2024 ATI-RRPV Contract was $36.4 million, comprised entirely of the cost-plus-fixed-fee, for thethree months ended* March 31, 2026*, and $19.3 million, comprising cost-plus-fixed-fee of $18.5 million and firm fixed-price milestone of $0.8 million for thethree months ended* March 31, 2025,based on costs incurred and the achievement of firm fixed-price milestones under the2024* ATI-RRPV Contract. Deferred government revenue represents amounts that have been received from HHS BARDA and the earnings process isnot yet complete. Deferred government revenue in current liabilities was $23,000 and $68,000 as of* March 31, 2026* and* December 31, 2025*, respectively. The remaining deferred government revenue as of* March 31, 2026*, will be recognized as revenue once the earnings process is complete.

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The Company believes that if the2024 ATI-RRPV Contract were to be terminated prior to completion of the Phase2b comparative study, the costs incurred through the effective date of such termination and any settlement costs resulting from such termination would be allowable costs. Cost reimbursement payments to the Company are provisional payments subject to adjustment upon annual audit by the government. The Company believes that revenue for periodsnot yet audited will be 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 becomes known.

2024 ASPR-BARDA Contract

In* January 2024,the Company was awarded a contract (as modified or amended, the“2024* ASPR-BARDA Contract”) by HHS BARDA with a base and all options value of $9.3 million. Under the2024 ASPR-BARDA Contract, the Company received an award to support clinical trial planning activities for a Phase2b clinical trial that would compare the Company’s XBB vaccine candidate to an mRNA comparator to evaluate efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and adverse events. The2024 ASPR-BARDA Contract originally had a period of performance term that was set to expire in* July 2024,but the Company entered into an amendment in July 2024that extended the period of performance expiration date into October 2024.The Company accounts for the2024* ASPR-BARDA Contract under ASC958-605 and recognizes revenue as donor-imposed conditions are met. Revenue from government contracts recognized on the2024 ASPR-BARDA Contract waszero for each of thethree months ended* March 31, 2026and2025*. Deferred government revenue represents amounts that have been received from HHS BARDA and the earnings process isnot yet complete. Deferred government revenue in current liabilities waszero as of* March 31, 2026* and* December 31, 2025*.

Revenue from License and Collaboration

On* November 4, 2025,the Company entered into the2025* 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 (the “Vaccine Candidate”). Pursuant to the2025 License and Collaboration Agreement, the Company granted Dynavax an exclusive, worldwide license to develop and commercialize the Company’s oral pill Vaccine Candidate for SARS-CoV-2, SARS coronavirus, or MERS coronavirus, including COVID-19 and all variants thereof. Under the terms of the2025 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 the2025 Securities Purchase Agreement. The2025 License and Collaboration Agreement provides that the Company continue to develop the Vaccine Candidate by conducting and completing its ongoing Phase2b clinical trial and delivering the end-of-Phase2 data package, performing its obligations under the2024 ATI-RRPV agreement and conducting additional development and manufacturing activities related to the Vaccine Candidate.

On* February 10, 2026,*Sanofi completed its acquisition of Dynavax. As a result of the consummation of the merger, Dynavax became an indirect wholly owned subsidiary of Sanofi.

Following the completion of the Company’s ongoing Phase2b clinical trial and a planned end-of-Phase2 meeting with the FDA, per the2025 License and Collaboration Agreement, Dynavax has the right to elect, in its sole discretion, to assume responsibility for the continued development of the Vaccine Candidate. If Dynavax elects to assume responsibility for such continued development of the Vaccine Candidate, then Dynavax has agreed to pay the Company an additional fee of $50.0 million. If Dynavax doesnot elect to assume responsibility for such continued development of the Vaccine Candidate, then the2025 License and Collaboration Agreement will terminate pursuant to its terms.

The Company determined that the2025 License and Collaboration Agreement represented a contract with a customer and should be accounted for in accordance with ASC606. The Company identifiedtwo performance obligations, (i) the exclusive license, together with the related transfer and manufacturing technology transfer (the “License Performance Obligation”), and (ii) the development program activities through delivery of theEOP2 Data Package, including participation in joint governance committees (the “Development Performance Obligation”).

The Company identified $25.8 million of total transaction price at inception, consisting of a non-refundable upfront payment of $25.0 million and the premium of approximately $0.8 million associated with Dynavax’s concurrent $5.0 million equity investment in the Company, which represented consideration in excess of the fair value of the common stock issued. The fixed consideration of $25.8 million was allocated to thetwo performance obligations on a relative standalone selling price basis. Revenue allocated to the License Performance Obligation was recognized at a point in time in thefourth quarter of2025 upon completion of the technology transfer, when Dynavax obtained the right to use and benefit from the licensed intellectual property. Revenue allocated to the Development Performance Obligation is recognized over time using an input method based on costs incurred relative to total estimated costs to complete the development program.

The2025 License and Collaboration Agreement also includes potential additional consideration in the form of evaluation fees, a $50.0 million election payment, regulatory and commercial milestone payments, and royalties on future product sales. Such amounts represent variable consideration and are included in the transaction price only to the extent that it is probable that a significant reversal of cumulative revenue recognized willnot occur. Sales-based milestones and royalties will be recognized as revenue when the underlying sales occur in accordance with the sales- or usage-based royalty exception in ASC606.

For thethree months ended* March 31, 2026and2025*, the Company recognized collaboration revenue of $2.8 million andzero, respectively, from the2025 License and Collaboration Agreement. As of* March 31, 2026*, the amount of deferred collaboration revenue was $12.2 million, of which $11.7 million was classified as current and $0.4 million as non-current. The remaining deferred collaboration revenue will be recognized as revenue once the earnings process is complete.

NOTE*6***.**** **Liabilities Related to Sale of Future Royalties

In* April 2016,Aviragen entered into a Royalty Interest Acquisition Agreement (the “RIAA”) with HealthCare Royalty Partners III, L.P. (“HCRP”). Under the RIAA, HCRP made a $20.0 million cash payment to Aviragen in consideration for acquiring certain royalty rights (“Royalty Rights”) related to the approved product Inavir in the Japanese market. The Royalty Rights were obtained pursuant to the collaboration and license agreements (the “License Agreement”) and a commercialization agreement that the Company entered into with Daiichi Sankyo. Per the terms of the RIAA, during thefirst* royalty interest period of* April 1, 2016through March 31, 2025,HCRP is entitled to thefirst* $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 the Company. Further, during thesecond* royalty interest period beginning* April 1, 2025and ending on December 24, 2029,HCRP is entitled to thefirst* $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 the Company. A shortfall occurs when, during an annual period ending on* March 31,for thefirst* royalty interest period of* April 1, 2016through March 31, 2025,the Company’s royalty payments fall below $3.0 million; and $2.7 million for thesecond* royalty interest period of* April 1, 2025and ending on December 24, 2029,excluding the period of April 1, 2028through December 24, 2029.In the event there shall remain any cumulative remaining shortfall amount as of December 24, 2029,*any royalties received from Daiichi Sankyo subsequently by the Company would be payable to HCRP until the cumulative remaining shortfall amount has been paid.

For avoidance of doubt, the RIAA states, in the event there is a remaining cumulative remaining shortfall amount as of* December 24, 2029,the Company shallnot* be obligated to pay HCRP any royalty payment beyond what the Company is paid from Daiichi Sankyo. The cumulative remaining shortfall amount is the aggregate amount of the remaining shortfall for each annual period, which was $6.7 million and $4.4 million as of* March 31, 2026* and* December 31, 2025*, respectively.

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Under the relevant accounting guidance, due to a limit on the amount of royalties that HCRP can earn under the RIAA, this transaction was accounted for as a liability that is being amortized using the effective interest method over the life of the arrangement. The Company hasno obligation to pay any amounts to HCRP other than to pass through to HCRP its share of royalties as they are received from Daiichi Sankyo. To record the amortization of the liability, the Company is required to estimate the total amount of future royalty payments to be received under the License Agreement and the payments that will be passed through to HCRP over the life of this agreement. Consequently, the Company imputes interest on the unamortized portion of the liability and records non-cash interest expense using an estimated effective interest rate. The royalties earned in each period that will be passed through to HCRP are recorded as non-cash royalty revenue related to sale of future royalties, with any excessnot subject to pass-through being recorded as royalty revenue. When the pass-through royalties are paid to HCRP in the following quarter, the imputed liability related to sale of future royalties is commensurately reduced. The Company periodically assesses the expected royalty payments, and to the extent such payments are greater or less than the initial estimate, the Company adjusts the amortization of the liability and interest rate. As a result of this accounting, even though the Company doesnot retain HCRP’s share of the royalties, it will continue to record non-cash revenue related to those royalties until the amount of the associated liability, including the related interest, is fully amortized.

The following table shows the activity within the liability account during thethree months ended* March 31, 2026* (in thousands):

NOTE*7***. Leases**

The Company has obtained the right of use for office and manufacturing facilities under five operating lease agreements with initial terms exceedingone year. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise.

As of* March 31, 2026*, the weighted average discount rate for operating leases with initial terms of more thanone year was 10.1% and the weighted average remaining term of these leases was 2.9 years. Discount rates were determined using the Company’s marginal rate of borrowing at the time each lease was executed or extended.

The following table summarizes the Company’s undiscounted cash payment obligations for its operating lease liabilities with initial terms of more than12 months as of* March 31, 2026* (in thousands):

The Company is also required to pay for operating expenses related to the leased space, including common area maintenance, taxes and insurance. The operating expenses are incurred separately and werenot included in the present value of lease payments. Operating lease expenses for thethree months ended* March 31, 2026and2025* are summarized as follows (in thousands):

NOTE*8***. Commitments and Contingencies**

As of* March 31, 2026*, the Company had approximately $19.3 million of non-cancelable purchase commitments, principally for clinical services which are expected to be paid within the next year. Approximately $18.2 million of non-cancelable purchase commitments are attributable to athird-party vendor that provides clinical services, that is reimbursable at approximately $19.6 million under a cost-plus-fixed-fees arrangement in the ATI-RRPV Contract.

In the ordinary course of business, the Company enters into agreements that* mayinclude indemnification provisions. Pursuant to such agreements, the Company mayindemnify, hold harmless and defend indemnified parties for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising fromthird*-party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions isnot determinable. The Company has also entered into indemnification agreements with certain officers and directors which provide, among other things, that the Company will indemnify and advance expenses incurred in connection with certain actions, suits or proceedings to such officer or director, under the circumstances and to the extent provided for therein, for expenses, damages, judgments, fines and settlements he or she* maybe required to pay in actions or proceedings which he or she is or may*be made a party by reason of his or her position as a director, officer or other agent of the Company, and otherwise to the fullest extent permitted under Delaware law and the Company’s Bylaws. The Company currently has directors’ and officers’ insurance.

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From time to time the Company* maybe involved in legal proceedings arising in connection with its business. Based on information currently available, the Company believes that the amount, or range, of reasonably possible losses in connection with any pending actions against it in excess of established reserves, in the aggregate, isnot* material to its consolidated financial condition or cash flows. However, any current or future dispute resolution or legal proceeding, regardless of the merits of any such proceeding, could result in substantial costs and a diversion of management’s attention and resources that are needed to run the Company successfully, and could have a material adverse impact on its business, financial condition and results of operations.

In* Augustand September 2020,two substantially similar securities class actions were filed in the U.S. District Court for the Northern District of California. Thefirst action, titledHimmelberg v. Vaxart, Inc. et al. was filed on August 24, 2020.Thesecond* action, titledHovhannisyan v. Vaxart, Inc. et al. was filed on* September 1, 2020 (together, the “Putative Class Action”). By Order dated September 17, 2020,thetwo* actions were deemed related. On* December 9, 2020,*the court appointed lead plaintiffs and lead plaintiffs’ counsel.

On* January 29, 2021,lead plaintiffs filed their consolidated amended complaint. On May 14, 2021,the court granted lead plaintiffs’ request to amend the consolidated amended complaint and denied defendants’ motions to dismiss as moot. On June 10, 2021,lead plaintiffs filed afirst* amended consolidated complaint, and on* August 9, 2021,lead plaintiffs filed a correctedfirst* amended consolidated complaint. Thefirst amended consolidated complaint, as corrected, named certain of Vaxart’s current and former executive officers and directors, as well as Armistice Capital, LLC (“Armistice”), as defendants. It claimedthree violations of federal civil securities laws; violation of Section10(b) of the Exchange Act and SEC Rule10b-5, as against the Company and all individual defendants; violation of Section20(a) of the Exchange Act, as against Armistice and all individual defendants; and violation of Section20A of the Exchange Act against Armistice. Thefirst amended consolidated complaint, as corrected, alleged that the defendants violated securities laws by misstating and/or omitting information regarding the Company’s development of a norovirus vaccine, the vaccine manufacturing capabilities of a business counterparty, and the Company’s involvement with Operation Warp Speed (“OWS”); and by engaging in a scheme to inflate Vaxart’s stock price. Thefirst amended consolidated complaint sought certification as a class action for similarly situated shareholders and sought, among other things, an unspecified amount of damages and attorneys’ fees and costs. On* July 8, 2021,all defendants moved to dismiss thefirst* amended consolidated complaint. By Order dated* December 22, 2021,the court granted the motion to dismiss by Armistice with leave to amend and otherwise denied the motions to dismiss. On July 27, 2022,lead plaintiffs filed a notice announcing that they had reached a partial settlement (the “Partial Settlement”) to resolve all claims against the Company and its current or former officers and/or directors in their capacity as officers and/or directors of the Company (the “Settling Defendants”). Pursuant to the Partial Settlement, the Company agreed to a settlement amount of $12.0 million with$2.0* million to be paid by the Company and the remainder to be paid by the Company’s insurers. On* November 2, 2022,the Company paid the $2.0 million settlement amount with respect to the Putative Class Action pursuant to the terms of the settlement agreement reached in that case. On November 14, 2022,lead plaintiffs filed asecond* amended consolidated class action complaint that purported to include new allegations to support claims against Armistice. By Orders dated* January 25, 2023,the court approved the Partial Settlement and entered judgment dismissing with prejudice all claims asserted in the Putative Class Action against the Settling Defendants. A jury trial on the claims asserted against Armistice commenced on April 14, 2026and concluded on April 28, 2026with a verdict entered in favor of Armistice and concluding that Armistice hadnot* engaged in either a scheme to inflate the price of Vaxart’s stock or insider trading in connection with its sales of Vaxart’s stock in* June 2020;post-verdict proceedings before the District Court are ongoing and the time for lead plaintiffs to lodge an appeal hasnot* yet expired.

On* October 23, 2020,a complaint was filed in the U.S. District Court for the Southern District of New York, entitledRoth v. Armistice Capital LLC, et al.* The complaint names Armistice and certain Armistice-related parties as defendants, asserting a violation of Exchange Act Section16(b) and seeking the disgorgement of short-swing profits. The complaint purports to bring the lawsuit on behalf of and for the benefit of the Company and names the Company as a “nominal defendant” for whose benefit damages are sought. Following discovery, a motion for summary judgment was filed by Armistice and the Armistice-related party defendants to dismiss the complaint. On* March 27, 2024,the court granted the motion for summary judgment and dismissed all claims in the complaint in their entirety. On April 11, 2024,the Plaintiff timely filed a notice of appeal of the court’s decision to the Second Circuit Court of Appeals, commencing appellate proceedings. In June 2024,Plaintiff filed a motion to the court of appeals to stay the appeal pending efforts to re-instate the complaint in the district court, which was granted by the court of appeals. In July 2024,Plaintiff filed a motion with the district court seeking to set aside the judgment and to re-instate the complaint. On August**15,* 2024, the district court denied Plaintiff’s motion to set aside the judgment. On* August 19, 2024,the court of appeals lifted the stay and, on August 28, 2025,*the court of appeals entered a judgment affirming the judgment of the district court. The time for Plaintiffs to file any appeal of that decision has since lapsed.

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On* January 8, 2021,a purported shareholder, Phillip Chan, commenced apro se* lawsuit in the U.S. District Court for the Northern District of California titledChan v. Vaxart, Inc. et al. (the “Opt-Out Action”), opting out of the consolidated Himmelberg v. Vaxart, Inc. et al. and Hovhannisyan v. Vaxart, Inc. et al. class actions, (together, the “Putative Class Action”). Because this complaint is nearly identical to an earlier version of a complaint filed in the Putative Class Action, the Opt-Out Action has been stayed while the Putative Class Action is pending.

NOTE9. Stock****holders’ Equity

The Company is authorized to issue 5,000,000 shares of preferred stock, $0.0001 par value per share. The Company’s board of directors* may,without further action by the stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of5,000,000* shares of preferred stock inone or more series and authorize their issuance. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of such series, any or all of which* maybe greater than the rights of the Company's common stock. The issuance of preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deterring or preventing a change of control or other corporate action. No shares of preferred stock are currently outstanding, and the Company hasno* present plan to issue any shares of preferred stock.

As of* March 31, 2026*, the Company was authorized to issue 350,000,000 shares of common stock, $0.0001 par value per share. Except as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, the holders of common stock possess all voting power for the election of the Company’s directors and all other matters requiring stockholder action. Holders of common stock are entitled toone vote per share on matters to be voted on by stockholders. Holders of common stock are entitled to receive such dividends, if any, as* maybe declared from time to time by the Company’s board of directors in its discretion out of funds legally available therefor. Inno* event will any stock dividends or stock splits or combinations of stock be declared or made on common stock unless the shares of common stock at the time outstanding are treated equally and identically. As of* March 31, 2026*, no dividends had been declared by the board of directors.

In* March 2025,the Company entered into the March 2025ATM with Citizens and B. Riley, pursuant to which the Company mayoffer 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 the2026* Shelf Registration Statement. 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 2025ATM. 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 2025ATM.No shares have been issued or sold under the March 2025ATM since the Company was suspended from trading on The Nasdaq Capital Market in July 2025.*

In the event of the Company’s voluntary or involuntary liquidation, dissolution, distribution of assets or winding-up, the holders of the common stock will be entitled to receive an equal amount per share of all the Company’s assets of whatever kind available for distribution to stockholders, after the rights of the holders of the preferred stock have been satisfied. There areno sinking fund provisions applicable to the common stock.

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The Company had shares of common stock reserved for issuance as follows:

The following warrants were outstanding as of* March 31, 2026*, all of which contain standard anti-dilution protections in the event of subsequent rights offerings, stock splits, stock dividends or other extraordinary dividends, or other similar changes in the Company’s common stock or capital structure, andnone of which have any participating rights for any losses:

NOTE10. Equity Incentive Plans

The Company has maintained the2019 Equity Incentive Plan and the2024 Inducement Award Plan for the issuance of stock options, stock appreciation rights, restricted stock awards, restricted stock units (“RSUs”), other stock awards and performance awards that* maybe settled in cash, stock, or other property to employees, directors and consultants. The terms of the2024* Inducement Award Plan are substantially similar to the terms of the2019 Equity Incentive Plan, with the exception that incentive stock options* may**not* be issued under the2024 Inducement Plan and equity awards under the2024 Inducement Plan (including nonqualified stock options, restricted stock, restricted stock units, and other stock-based awards)* maybe issued only to an employee who is commencing employment with the Company or any subsidiary or who is being rehired following a bona fide interruption of employment by the Company or any subsidiary, in either case if he or she is granted such award in connection with his or her commencement of employment and such grant is an inducement material to his or her entering into employment with the Company or such subsidiary. The Company also maintains the2022* Employee Stock Purchase Plan (“ESPP”) for its employees.

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A summary of stock option and RSU transactions during thethree months ended* March 31, 2026* is as follows:

As of* March 31, 2026*, there were 27,767,619 options outstanding with a weighted average exercise price of $1.62, a weighted average remaining term of 7.40 years, and an aggregate intrinsic value of $667,000. Of these options,13,614,279 were vested, with a weighted average exercise price of $2.59, a weighted average remaining term of 6.04 years, and an aggregate intrinsic value of $161,000.

No options were exercised during thethree months ended* March 31, 2026*. The Company received $3,000 for the 3,625 options exercised during thethree months ended* March 31, 2025*, which had an intrinsic value of $0. The aggregate intrinsic value represents the total pre-tax value (i.e., the difference between the Company’s stock price and the exercise price) of stock options outstanding as of* March 31, 2026and2025*, respectively, based on the Company’s common stock closing price of $0.61 on* March 31, 2026* and $0.85 on* March 31, 2025*, which would have been received by the option holders had all their in-the-money options been exercised as of that date.

The weighted average grant date fair value of options awarded in thethree months ended* March 31, 2026and2025*, was $0.59 and $0.46, respectively. Their fair values were estimated using the following assumptions:

The Company measures the fair value of all stock-based awards on the grant date and records the fair value of these awards, net of estimated forfeitures, to compensation expense over the service period. Total stock-based compensation recognized for options, RSUs and ESPP was as follows (in thousands):

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As of* March 31, 2026*, the unrecognized stock-based compensation cost related to outstanding unvested stock options and RSUs expected to vest was $12.1 million, which the Company expects to recognize over an estimated weighted average period of 3.0 years.

NOTE*11***. Net Income (Loss)**** **Per Share Attributable to Common Stockholders

The following table presents the calculation of basic and diluted net income (loss) per share (in thousands, except share and per share amounts):

For thethree months ended* March 31, 2026,1,534,751 dilutive shares were included in the diluted weighted average share count. For thethree* months ended* March 31, 2025,*all potentially dilutive securities were excluded from the diluted EPS computation because their effect would have been antidilutive given the net loss in that period. The following table summarizes the potentially dilutive securities excluded from the computation:

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NOTE 12. Segment Reporting

The Company operates inone reportable segment, which is the discovery and development of oral recombinant protein vaccines, based on its proprietary oral vaccine platform. The accounting policies of the segment are the same as those described in the summary of significant accounting policies. The determination of a single business segment is consistent with the consolidated financial information regularly reviewed by the Chief Executive Officer as chief operating decision maker (the “CODM”) in assessing segment performance and deciding how to allocate resources on a consolidated basis.

The CODM uses consolidated net income (loss) to evaluate the Company’s spend and monitor budget versus actual results. The monitoring of budgeted versus actual results is used in assessing performance of the segment and in establishing resource allocation across the organization. The measure of segment assets is reported on the consolidated balance sheets as total assets.

The Company’s segment revenue, segment loss, significant segment expenses, and other segment items consist of the following (in thousands):

(A) Other segment items included in other income (expense), net.

Note 13. Subsequent Events

Equity Line of Credit

In* April 2026,the Company entered into the April 2026ELOC and a registration rights agreement with LPC, pursuant to which LPC committed to purchase up to the Commitment Amount, $25.0 million, of the Company’s common stock (“Purchase Shares”), subject to certain limitations and conditions. The Company has the right, butnot* the obligation, to sell shares of common stock to LPC, and LPC is obligated to make purchases as directed by the Company, subject to the conditions set forth in the agreement. Sales* mayoccur from time to time, at the Company’s sole discretion, over a24*-month period commencing upon satisfaction of certain conditions, including effectiveness of a registration statement covering the resale of shares of common stock by LPC. The purchase price per share of common stock for regular purchases will be equal to 97% of the lower of (i) the lowest sale price on the applicable purchase date or (ii) the arithmetic average of thethree lowest closing sale prices during theten consecutive business days ending on the business day immediately preceding such purchase date. The Company* mayalso direct accelerated purchases at prices based on market prices on the applicable purchase date. The April 2026ELOC prohibits sales if such shares of common stock, when aggregated with all other shares of common stock then beneficially owned by LPC, would result in LPC owning more than 4.99% of the Company’s then outstanding common stock. The Company has the right to terminate the agreement at any time after the Company has satisfied all the conditions for sales to be made pursuant to the April 2026ELOC, withone* business day notice, atno cost or penalty. The Company issued 447,067 shares of common stock to LPC as consideration for its commitment to purchase shares of common stock under the* April 2026*ELOC.

The shares will be sold pursuant to an effective registration statement. The Company intends to file a registration statement with the SEC covering the resale by LPC of the Purchase Shares* maybe issued to LPC under the April 2026ELOC, as well as the 447,067 shares of common stock issued to LPC as consideration for its commitment to purchase shares of common stock under the April 2026*ELOC.

Amendment to Lease Agreement

In* April 2026,the Company entered into an amendment (the “Utah Avenue Lease Amendment”) to its lease agreement (the “Utah Avenue Lease”) with a landlord (the “Utah Avenue Landlord”) relating to certain properties currently leased to the Company that are located on Utah Avenue in South San Francisco, California. Pursuant to the Utah Avenue Lease Amendment, the Company agreed to lease from the Utah Avenue Landlordtwo* additional suites in an additional building on Utah Avenue with a total of approximately 3,531 rentable square feet of space (the “Additional Leased Space”), effective as of* May 14, 2026 (the “Expansion Commencement Date”). The term of the lease of the Additional Leased Space is36* months from the Expansion Commencement Date, unless earlier terminated pursuant to the terms of the Utah Avenue Lease Amendment and the Utah Avenue Lease.

Appointment of Dr. James B. Breitmeyer, M.D., Ph.D. to Board of Directors

On* April 23, 2026**,* following a recommendation by the Nominating and Governance Committee of the Board of Directors, the Company's Board appointed James B. Breitmeyer, M.D., Ph.D. to serve on the Board, effective** April 23, 2026,** until Dr. James B. Breitmeyer, M.D., Ph.D.’s successor is elected and qualified, or sooner in the event of his death, resignation, or removal. The Board has determined that Mr. James B. Breitmeyer, M.D., Ph.D. meets the requirements for independence standards as adopted by the Board.

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