Vaxart Q4 2025 Earnings Call - Dynavax Pact Validates Platform, Sentinel Cohort Safety Readout Early Q2 2026

Conference Operator, Moderator: Greetings, and welcome to the Vaxart fourth quarter business update and year-end 2025 financial results conference call. A question-and-answer session will follow management’s opening remarks. As a reminder, this conference is being recorded. I would now like to turn the webcast over to your host, Edward Berg, Senior Vice President and General Counsel. Thank you. You may begin.

Edward Berg, Senior Vice President and General Counsel, Vaxart: Good afternoon and welcome to today’s call. Joining us from Vaxart are Steven Lo, Chief Executive Officer, Dr. Sean Tucker, Founder and Chief Scientific Officer, Dr. James F. Cummings, Chief Medical Officer, and Jeroen Grasman, Chief Financial Officer. Before we begin, I would like to remind everyone that during this conference call, Vaxart may make forward-looking statements, including statements about the company’s financial results, financial guidance, its future business strategies and operations, and its product development and regulatory progress, including statements about its ongoing or planned clinical trials. Actual results could materially differ from those discussed in these forward-looking statements due to a number of important factors, including uncertainty inherent in the clinical development and regulatory process and other risks described in the Risk Factors section of Vaxart’s most recently filed annual report on Form 10-K and on other periodic reports filed with the SEC.

Vaxart undertakes no obligation to update any forward-looking statements after the date of this call. I’ll now turn the call over to Steven Lo. Steve.

Steven Lo, Chief Executive Officer, Vaxart: Thanks, Ed, and thanks to all of you for joining us this afternoon. I’ll begin today’s call with several business updates and will then pass the call to James and Sean for the latest program developments. Jeroen will then share an update of our fourth quarter and full year 2025 financial results, and I have a few closing comments before we open the call for your questions. Now moving to our recent operational updates. Vaxart achieved several recent key milestones. First, we established a partnership with Dynavax for our oral COVID-19 vaccine candidate. Second, we expanded our clinical body of evidence by publishing the complete data set from the clinical study of our oral norovirus vaccine candidate in lactating mothers.

Third, we continued to manage our costs as evidenced by our entering into a lease termination agreement that will provide significant cost savings by allowing us to terminate one of our leases early. As announced in November 2025, we established a partnership with Dynavax for our oral COVID-19 vaccine candidate. At the time of the announcement, we received a $25 million upfront payment and a $5 million equity investment, which was at a premium to the closing price. This partnership provides significant validation of our oral vaccine platform’s potential, coming from a company with a proven track record in developing and commercializing innovative vaccines. It also extends our cash runway. In late December 2025, Sanofi announced its acquisition of Dynavax, a transaction that officially closed on February 10 of this year.

Sanofi is a global leader in the vaccine space, and we are pleased to be moving forward with Dynavax as a Sanofi company. Over the past three months, we have established a highly productive working relationship with our collaborators, and our focus remains on executing and completing the phase 2B trial and delivering those results. Under the terms of our agreement, we will receive an additional $50 million if Dynavax elects to continue development following submission of the phase 2B data to the FDA. We also remain eligible for up to $195 million in future regulatory milestones, $425 million in sales milestones, and tiered royalties in the low to mid-teens. This agreement represents a total potential value of up to $700 million in license, regulatory and milestone fees, tiered royalties, and the equity investment.

Previously, we discussed our commitment to managing our financial resources for maximum effect. This includes pursuing revenue-generating business development agreements such as our partnership with Dynavax. It also includes looking for ways to reduce our operating costs without compromising our ability to realize the potential value of our pipeline programs and platform technology. Towards this end, in December 2025, we entered into a lease termination agreement with one of our landlords, which will allow us to terminate one of our leases on May 15, 2026, rather than March 31, 2029. This accelerated termination will help to reduce our operating expenses and enhance our ability to focus our financial resources on advancing our lead programs. I’ll now turn the call over to Dr. Cummings for an update on the status of our clinical programs. James.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Thanks, Steve, and thanks to everyone for joining today’s call. As a reminder, we are currently conducting a phase 2B trial of our oral COVID-19 vaccine candidate compared with an mRNA vaccine.

The primary endpoint of this study is the relative efficacy of our oral pill vaccine compared with the mRNA vaccine for 12 months post-vaccination. The trial will measure efficacy for symptomatic and asymptomatic disease, systemic and mucosal immune induction, and adverse events in each cohort. Most of you are aware that this trial initially was designed to enroll 400 subjects in a sentinel cohort designed to assess safety of our oral COVID-19 vaccine candidate and 10,000 subjects in the KP2 cohort, with half receiving our oral candidate and half receiving an injected mRNA vaccine. We announced in October 2025 that BARDA amended the work order for this trial and is now providing funding for follow-up for the approximately 5,400 subjects enrolled in the trial prior to a stop work order issued on behalf of BARDA in August 2025.

This comprises 400 subjects in the sentinel cohort and approximately 5,000 subjects in the KP2 cohort enrolled in this trial. As COVID-19 continues to impact global health, the need for next-generation solutions remains clear. We expect to report 12-month top-line data from the 400-participant sentinel cohort early in the second quarter of 2026. The actual timing will be determined in collaboration with BARDA. As previously shared, we are contractually required to consult with and receive approval from BARDA regarding the timing and content of all press releases related to this trial. When announced, we expect to include data related to the primary safety endpoints for the sentinel cohort, as well as initial data on efficacy measures. It’s important to remember that the 400-person sentinel cohort was established specifically to assess safety and not designed to determine efficacy.

The data from the 5,000-subject KP2 cohort will provide efficacy insights, and we expect to report them late in the fourth quarter of 2026. Here again, the actual timing will be determined in collaboration with BARDA. As I’ve commented before, we believe the results of this trial will provide important insights into potential of our COVID-19 candidate as well as our oral pill vaccine platform technology. The former is critical to advancing development of the COVID-19 candidate, while the latter is expected to inform development of our other pipeline assets. Our oral norovirus vaccine candidate is one of those assets. As Steve mentioned at the start of the call, we published a complete data set from the clinical study of our oral norovirus vaccine candidate in lactating mothers in January 2026 in npj Vaccines.

The phase 1 multi-center randomized double-blind placebo-controlled single-dose dose-ranging study was designed to evaluate the safety, tolerability, and immunogenicity of an orally administered bivalent GI.1 GII.4 norovirus vaccine in healthy lactating women. The primary outcomes of the study were safety and reactogenicity and breast milk and serum norovirus-specific IgA. I’ll briefly review the information that was provided in our January 15, 2026 press release announcing the data publication. The study enrolled 76 women 18-43 years of age at 5 sites in South Africa. Participants were randomized into high or medium dose vaccine or placebo. The data demonstrate that the vaccine was safe and well tolerated, and reports of mild or moderate adverse events or AEs were similar between the placebo group and each of the vaccine groups, and no AEs beyond grade 2 were reported.

Results for serum and breast milk IgA at day 29 post-vaccination showed that serum norovirus-specific IgA rose an average of 5.6-fold in response to GI.1 and 4.7-fold in response to GII.4 in the high-dose group. Breast milk norovirus-specific IgA rose on average 4-fold in response to GI.1 and 6-fold in response to GII.4 in the high-dose group. Each of these breast milk increases was statistically significant and maintained through day 180. The passive transfer of IgA to infants was exploratory, but a highly compelling outcome.

The data show a consistent trend of increased GI.1 and GII.4 specific IgA in the stool from the paired infants of vaccinated women at days 29 and 60 and demonstrate a positive association between levels of IgA in maternal breast milk and infant stool, supporting the hypothesis of passive transfer of mucosal immunity. This observed transfer of antibodies suggests that the oral norovirus vaccination could enable a novel approach to confer mucosal antiviral immunity to infants who are highly vulnerable to norovirus infection. Children under the age of five years can experience severe disease from norovirus infection, particularly in under-resourced areas. The potential to protect infants from severe norovirus-associated disease through oral vaccination of their mothers could have important public health benefits with respect both to reducing individual morbidity and mortality, as well as limiting spread of a highly contagious virus.

The results of this study add to the growing body of evidence supporting the potential of our oral norovirus vaccine candidate in addressing a significant unmet public health need, as currently there is no approved vaccine for norovirus. I’ll also remind you of an additional piece of evidence from our norovirus program that we reported in June 2025, which was the result of a phase 1 trial to compare our second-generation vaccine constructs against the original first-generation oral vaccine to see if the new formula induced stronger immunity. As reported, the study showed that the second-generation constructs produced significantly higher antibody responses, 141% increase for one strain and 94% increase for the other, compared to the first-generation vaccines. These data help to advance not only our norovirus program, but our oral pill vaccine platform more broadly.

The technology underlying our second-generation norovirus constructs has also been incorporated into the other programs in our pipeline. Based on the results of the head-to-head study, we believe that this will increase the immunogenicity of our COVID-19 seasonal and pandemic flu and HPV vaccine candidates. I’ll turn the call over to Dr. Sean Tucker for an update on our norovirus program, including some of our preclinical research activities. Sean?

Dr. Sean Tucker, Founder and Chief Scientific Officer, Vaxart: Thank you, James. We are building a robust body of evidence supporting the potential of our oral norovirus vaccine program, and adding to that body of data is a key part of our strategy for advancing our business development efforts around this promising asset. As we have previously discussed, we are positioned to initiate the next clinical trial of our second-generation norovirus vaccine constructs in 2026, pending a partnership or other funding. As part of our evidence generation strategy, we have been exploring how GII.4 construct cross-reacts with and protects against the GII.17 strain of norovirus in preclinical studies. GII.4 typically is the predominant strain underlying the majority of norovirus infection, but there was a significant GII.17 outbreak in late 2024 and continuing into 2025.

We have previously shown robust cross-reactivity of our COVID-19 vaccine candidates with multiple SARS-CoV-2 variants, and these preclinical studies are intended to provide insight into the potential utility of our norovirus constructs against additional norovirus strains, such as GII.17. The ability to demonstrate this type of cross-reactivity could potentially increase the utility and consequently the value of our norovirus vaccine program by enabling the use of our current constructs to protect against a broader spectrum of norovirus strains. We look forward to sharing the results with these studies with you later in 2026 and if positive, we’ll also include them in the data package that underlies our partnership discussions around this potentially first-in-class vaccine. I’ll now hand the call over to Jeroen for a brief discussion of our financials. Jeroen?

Jeroen Grasman, Chief Financial Officer, Vaxart: Thank you, Sean. The details of our fourth quarter and full year 2025 financial results are summarized in today’s press release. Revenue for the full year 2025 was $237.3 million compared to $28.7 million for the full year 2024. Revenue in the full year 2025 and full year 2024 were primarily from government contracts related to the BARDA contract awarded in June 2024, with 2025 also including revenue recognized from the Dynavax license and collaboration agreement signed in November 2025. Vaxart ended the fourth quarter with cash equivalents and investments of $63.8 million. Based on current plan, Vaxart expects cash runway into the second quarter of 2027.

Vaxart will continue to remain aggressive in seeking strategic partnerships, pursuing other non-dilutive funding options, and managing our expenses prudently in order to extend our cash runway. I will now turn the call back to Steve for closing remarks.

Steven Lo, Chief Executive Officer, Vaxart: Thank you, Jeroen. Thanks again to all of you for joining us today. We remain very optimistic about the potential of our COVID-19 and norovirus oral vaccine programs to provide important public health benefits while creating value for our shareholders. Our priorities for 2026 are to execute on the data collection and analysis for the COVID-19 clinical trial and to secure a partnership or other funding that will support advancement of our norovirus program. We look forward to sharing top-line results from the 400-subject Sentinel cohort of the COVID-19 trial early in the second quarter of 2026, and data from the 5,000-subject KP2 cohort at the end of 2026.

As we focus our business development efforts on the norovirus program, we also are continuing to explore potential licensing or partnership opportunities for our earlier stage assets, including our seasonal and pandemic flu candidates and our HPV program. We believe that our oral pill vaccine platform has potential as a disruptive technology that could address public health challenges and emerging personal preferences regarding vaccination. We are committed to realizing the value of this platform and are pursuing a variety of approaches to achieve this goal for our shareholders and for the many people who would benefit from innovative vaccines that address unmet public and personal health needs. Before we take your questions, I’d like to remind our listeners that we have a scheduled webcasted fireside chat tomorrow, Friday, March 13 at 4:30 P.M. Eastern Time.

At the fireside chat, we look forward to addressing more of the frequently asked questions we have received from our stockholders. As a reminder, you can submit written questions to [email protected]. We will do our best to answer as many questions as possible at the fireside chat. Since we have the fireside chat tomorrow, we will not take written questions on the call today. Thanks, everyone, for your time today. Operator, you may open the line for questions.

Conference Operator, Moderator: Thank you. With that, we will now be conducting a question-and-answer session. If you would like to ask a question, please press star one on your telephone keypad. Confirmation tone will indicate that your line is in the question queue. For participants using speaker equipment, it may be necessary to pick up the handset before pressing the star keys. One moment while we poll for questions. Our first question comes from the line of Cheng Li with Oppenheimer & Co. Please proceed with your question.

Cheng Li, Analyst, Oppenheimer & Co.: Hi team. Thanks for taking the questions and congrats on the quarter. Maybe two from us. First, it seems like the 400-person sentinel cohort data, there’s like a slight delay. I think the timing is now early second quarter compared to prior guidance on like late first quarter. Curious like any color you can share on the change and also like follow-up question is like how to frame the expectation on this 400-person sentinel cohort data and way through to the full Phase 2B data. Thank you.

Steven Lo, Chief Executive Officer, Vaxart: Great. Hi, Cheng Li. Thanks for the two questions. Those two questions are definitely appropriate for Dr. Cummings. James will address them. Yes, just to acknowledge, you know, prior guidance was towards the end of first quarter and now the guidance is early second quarter. Since James has a lot of interactions with BARDA, he can provide a little more detail on the reasons based on your question and the second question as well.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Thanks, Steve. You know, we’ll be reporting the 12-month top line data that we have for the 400 participant cohort, and that’s going to include data related to the primary safety endpoints. That’s why we did that cohort, right? It’s a safety cohort. That’s why it was designed. As well as some initial data on efficacy measures. As I mentioned, you know, that 400 person cohort designed for safety, right? The data from the 5,000 person KP2 cohort, that will provide some efficacy insights, which we expect to report in the fourth quarter of 2026. You know, any of the discussions we have in terms of releasing data, analyzing data, et cetera, it’s made in conjunction with our partners at BARDA. They have a say as to what and when gets delivered.

In working with them, that’s why I think we see a slight change there. Over.

Steven Lo, Chief Executive Officer, Vaxart: Great. Thanks. James, if you want to take the second question on as well in terms of, and you mentioned this during the comments as well, the potential read-through from the 400 to the approximately 5,000.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: As I was trying to phrase it, the 400-person safety cohort will be or should be some data coming in Q2. The larger, more robust data set for the 5,000-person KP2 cohort will give insights along with efficacy insights and safety and immunogenicity. We’ll have top line data from that coming in, we project Q4 of this year with likely immunogenicity results to follow.

Steven Lo, Chief Executive Officer, Vaxart: Great. Thanks. Thanks, James. Cheng, any more questions?

Cheng Li, Analyst, Oppenheimer & Co.: I think that’s all from us. Thanks again.

Steven Lo, Chief Executive Officer, Vaxart: Great. Thanks. Thanks for calling in.

Conference Operator, Moderator: Thank you. Our next question comes from the line of Mayank Mamtani with B. Riley Securities. Please proceed with your question.

Mayank Mamtani, Analyst, B. Riley Securities: Yes. Good afternoon, team. Thanks for taking our questions. First on the COVID program. Now you obviously have multiple parties here, very serious, you know, vaccine parties here, BARDA and also Sanofi after change of control. I was wondering how decision points would be for next steps after you have the Sentinel data in 2Q and the larger robust data set in 4Q. Also just to confirm, you’d not have any immunogenicity data as part of this 2Q update? Then I have a quick follow-up.

Steven Lo, Chief Executive Officer, Vaxart: Great. Hi, Mayank. Thanks for the question. Let me address the first part and then James can talk about what we’re going to see in the Sentinel 400. Just as a reminder to our listeners of the way that our agreement is set up both with BARDA and Dynavax, a Sanofi company, is that Vaxart and BARDA are responsible for the Phase 2B part of the clinical trial. This is basically still under our oversight. At the end of Phase 2, Dynavax would then have the opportunity to decide, once the end of Phase 2 package to the FDA is completed, to decide on whether they want to opt in or not.

You know, I think the good news is we’ve had, as I mentioned earlier, quite a bit of interactions with Dynavax, and that’s going well. Of course, we have our interactions with BARDA. I’ll turn it over to James to comment further on that, and then also, again, the Sentinel 400.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Sure. Thanks, Steve, and thanks, Mike, for the question. You know, when we’re looking at that preliminary top-line data, the first things we’ll be able to produce will be the safety, you know, overall look and then also some insights into the efficacy. The immunogenicity data is work that is done right now primarily by our partners at BARDA. That takes a little longer to execute. That would be following or after we have the initial data tranche, if you will. That’s my expectation, not just for the Sentinel 400, but likely for the KP2 5,000-person cohort as well.

Mayank Mamtani, Analyst, B. Riley Securities: Understood. Thank you.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Thanks.

Mayank Mamtani, Analyst, B. Riley Securities: On the norovirus second gen candidate, has there been any regulatory input on the endpoint constructs you could be looking to evaluate in this next phase 2 study? I guess that’s a Sean question or James question.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Yeah, I’ll take it, Mayank. We’ve had discussions with the FDA. As you know that a Phase 2B study, the primary endpoint there is safety, right? We’ll be collecting safety on that as well as immunogenicity and moving that program forward when, you know, pending having a partner. Steve, any other comment on that?

Steven Lo, Chief Executive Officer, Vaxart: Yeah, I think that’s right. Not sure, Mike, if you have sort of a follow-up question, but as James mentioned, right, we have always been interacting with the FDA on our study here.

Mayank Mamtani, Analyst, B. Riley Securities: Understood. Thank you guys, and look forward to the early 2Q updates here. Thank you.

Dr. James F. Cummings, Chief Medical Officer, Vaxart: Okay, great.

Steven Lo, Chief Executive Officer, Vaxart: Thanks for calling in.

Conference Operator, Moderator: Thank you. With that, ladies and gentlemen, that does conclude the question and answer session as well as today’s teleconference. We thank you for your participation, and you may now disconnect your lines at this time and have a wonderful rest of your day.