Vaxart Inc (VXRT) 2023 Q1 法說會逐字稿

Greetings and welcome to the Vaxart's business update and first-quarter 2023 financial results conference call. A questions-and-answers session will follow management's opening remarks. (Operator Instructions)

As a reminder, this conference is being recorded. I would now like to turn the webcast over to your host, Ed Berg, Senior Vice President and General Counsel.

Good afternoon, and welcome to today's call. Joining us from Vaxart are Andrei Floroiu, Chief Executive Officer; Dr. Sean Tucker, Founder and Chief Scientific Officer; Dr. James Cummings, Chief Medical Officer; and Phillip Lee, Chief Financial Officer.

Before we get started, 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 differ materially 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 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 Andrei Floroiu. Andrei?

Thank you, Ed. And thank you to all of you for joining us today. On today's call, our team will highlight the progress we have made on our norovirus oral pill vaccine program during the quarter. We will also discuss updates on our plans for an oral pan-betacoronavirus vaccine and showcase data that demonstrate the unique benefits of our platform.

Starting with norovirus, most notably in the quarter, we initiated our Phase 2 dose-ranging study for our bivalent norovirus oral vaccine candidate. We remain on track to deliver on our planned milestones for 2023, with anticipated data readouts for both the dose-ranging study and for our ongoing Phase 2 challenge study of our G11 monovalent norovirus vaccine candidate later this year.

James will provide more details on both studies in a moment. But first, a quick reminder on why this program and these studies are so important for global public health and why we are committed to Vaxart's oral pill norovirus vaccine approach.

Norovirus is a significant public health issue, which leads to a significant economic burden in developed countries, and there is no approved vaccine. More than 21 million people are infected in the US each year, resulting in an annual disease burden of more than $10 billion in the US alone.

It is important to note that norovirus predominantly affects two age segment: children under the age of five and older adults. There are about 20 million kids in the US and about 55 million older adults over the age of 65. Additionally, there are approximately $15 million other Americans who can benefit from a norovirus vaccine such as healthcare and childcare service providers, bringing our total domestic market opportunity to approximately 90 million Americans.

In the US, most people are concerned about salmonella or E. coli. But if you look at the total number of cases, norovirus is the most frequent foodborne illness, by far. If you've been following current events, you know that everyone is at risk for norovirus, in schools, workplaces, and many other places where people gather in large numbers.

People who experience norovirus symptoms are missing school and work and are not able to perform their daily functions. We believe that our norovirus vaccine program has the potential to address the need and the tremendous disease burden that norovirus carries both in the US and around the world. Today, we have produced data from six completed norovirus clinical trials that have enrolled nearly 350 subjects. These data have shown immune responses from our vaccine to be strong, long-lasting, comparable to naturally infection from norovirus, and similar in both elderly and young adult population, a result that generally is not seen with injectable vaccines.

In March, we showcased our differentiated norovirus program on a virtual KOL call that we sponsored with leaders in the norovirus vaccine development. These experts shared their insights and perspectives on the global need for a safe, effective, and readily deployable norovirus vaccine.

We hope that many of you were able to join this informative event as we continue to educate the financial community about the magnitude of the unmet need and the opportunity for a norovirus vaccine. A replay of that event is available on our Investor Relations section on our website at www.vaxart.com.

Looking ahead, we have several important clinical milestones this year, and we remain on track to achieve them. First, we expect to report topline data from the ongoing Phase 2 dose-ranging study of our bivalent norovirus vaccine candidate in mid-2023. Next, we anticipate reporting topline data from the ongoing Phase 2 challenge study of our G11 monovalent norovirus vaccine candidate in the third quarter of this year.

And then, we look forward to initiating this year, the Bill & Melinda Gates Foundation-funded clinical trial to evaluate the ability of our norovirus vaccine candidate to induce antibodies in breast milk and transfer those antibodies to young infants.

Taken together, these milestones have the potential to support the continued advancement of Vaxart's norovirus program towards a Phase 3 trial, while also potentially providing further validation of the promise of our norovirus pill vaccine platform. Norovirus continued to remain relevant, both nationally and globally, and we are encouraged by this opportunity to advance our oral pill vaccine technology.

Now I'll turn the call over to James for a review of our norovirus program. James?

Thanks, Andrei. We're really proud of our clinical team for their continued efforts to advance our mission and make meaningful progress with the Vaxart platform.

During the first quarter of this year, we dosed the first subject in the Phase 2 dose-ranging study of our bivalent norovirus oral vaccine candidate. Recall that this candidate contains two very important genotypes, G11 and G24, which have caused the majority of norovirus disease in humans over the past 20 years.

As a reminder, this trial enrolled 135 healthy adults at three sites here in the United States. The first 10 sentinel subjects received open-label, high-dose vaccine, and the remaining subjects were randomized to high or low-dose vaccine or placebo. Each of the vaccine arms has 50 subjects and the placebo arm has 25 subjects. The primary endpoints are safety and immunogenicity in order to determine a dose level for the Phase 3 development.

Enrollment was completed in mid-April, and we expect to report topline data from this study in the middle of this year. If successful, the next step will be a Phase 2b study leading to an end-of-Phase 2 meeting with the FDA in 2024.

In March, we announced the expansion in the number of cohorts in our ongoing Phase 2 G11 norovirus challenge study, measuring the efficacy and safety of our monovalent norovirus vaccine candidate. This study is also designed to identify a correlate of protection between immune responses to the vaccine and a reduction in the risk of norovirus infection and/or acute gastroenteritis. Enrollment in this ongoing double-blinded study is completed, and we continue to expect to report topline data in the third quarter of 2023.

In April, I presented on previously disclosed data from our norovirus program at the World Vaccine Congress in Washington, D.C. These data demonstrate that our oral pill bivalent norovirus vaccine candidate has many broad advantages, including the following. It induces broad immune responses via both mucosal and systemic responses. Immune response rates were above 90% for the high-dose. Immune responses were durable, they lasted for more than 200 days. Vaccine responses can be boosted after one year. Immune responses in the elderly, those aged 55 to 80 years in this study were very similar to those in younger adults aged 18 to 49. And finally, Vaxart's norovirus vaccine has a clean safety profile and has been well tolerated in this and all of our clinical trials to date.

Next week, we'll make three presentations at the 8th International Calicivirus Conference in Rotterdam, the Netherlands. Dr. Sean Tucker, our Founder and CSO, will be presenting a paper on breast milk antibodies and the potential ability to block transmission. Dr. Becca Flitter will present data demonstrating that boost administration of our oral norovirus vaccine candidate at 18 months after bivalent immunization is effective in inducing potent immune responses. And lastly, I'll be presenting an overview of Vaxart's bivalent vaccine efforts to date, as well as providing additional details on our studies in elderly subjects.

We continue to believe in the potential of our bivalent norovirus candidate as we target a BLA submission and possible FDA approval. We look forward to updating you on our progress as we provide updates from our concurrent Phase 2 clinical trials.

I'll now turn the call over to our Founder and Chief Science Officer, Dr. Sean Tucker, for an update on our pan-betacoronavirus program. Sean?

Thanks, James. Our research team has made tremendous strides in publishing clinical and preclinical data and presenting that data in front of important gatherings of scientific and governmental leaders. During the World Vaccine Congress last month, I presented previously published data from Vaxart studies, demonstrating our vaccine platform's ability to block transmission and boost existing COVID-19 vaccines.

We believe Vaxart COVID-19 vaccine has a favorable immune profile, achieving all of the following objectives. It is room temperature stable. It is easy to administer. It induces serum antibody responses and serum neutralizing antibody responses. It induces potent T cell responses. It creates a mucosal immune response. It can inhibit virus transmission. It is cross-reactive against SARS-CoV-2 variants and other betacoronaviruses. And it importantly boosts the most important COVID vaccines.

Based on all of the mucosal cross-reactivity data we have reported to date in our COVID clinical vaccine studies, we believe we may be able to create an oral pan-betacoronavirus vaccine. We continue to develop new constructs that enhance pan-betacoronavirus cross-reactivity, and we plan to advance these to the clinic when we are ready.

Such a vaccine would make it easier to both protect against current circulating viruses and to future-proof the vaccine, either against emerging coronavirus threats or other betacoronaviruses, making it a valuable tool for pandemic preparedness.

We believe this approach makes tremendous sense. There's continued interest in next-generation COVID-19 vaccine from regulatory and governmental bodies, as evidenced by the Biden administration's reported proposed commitment of up to $5 billion for such next-generation coronavirus vaccines. We look forward to continuing to engage with the government with the goal of obtaining funding for our pan-betacoronavirus program.

I'll now turn the call over to Phil for the discussion of the financials. Phil?

Thanks, Sean. The details of our financial results for the first three months of 2023 are summarized in today's press release. Vaxart ended the first quarter of 2023 with cash, cash equivalents, restricted cash, and marketable securities of $71.8 million compared to $95.7 million as of December 31, 2022. The decrease was primarily due to cash used in operations as we advanced our norovirus program. We continue to expect our current cash position provides us with runway into the second quarter of 2024.

On behalf of all of us at Vaxart, I'd like to thank you for your time today. We will now open the call for your questions.

(Operator Instructions) Mayank Mamtani, B. Riley.

Good afternoon, team. Thanks for taking our questions. So you seem to have a mRNA peer join in this effort to develop a norovirus vaccine, which validates the disease burden and market opportunity that you guys have been talking for a while. And you obviously are miles ahead here in terms of being in Phase 2. Could you just talk a little bit about the platform differences, advantages relative -- with your platform relative to say, mRNA? And then I have a follow-up.

Hi, Mayank. Yeah. Let me tell you a little bit about, obviously, I think our platform will be very good from the standpoint of listening antibody responses in mucosal surfaces. And certainly norovirus is something that infects the intestinal space. We do know we make very strong intestinal antibodies, so we think we have an advantage.

As you know, mRNA vaccines can be very good at making serum antibody responses, but those tend to be a little more transient. I think our data, at least of norovirus is that we can at least have our antibodies in the serum last for more than 200 days. So I think we have some significant advantages and obviously, we're further ahead.

Great. And then on the challenge study for the monovalent, are you guys able to comment on how the expectation of events that you had when you designed the study relative to where you are? And anything else that you guys have learned as you have been executing on this study versus your original plan, that would be great. And thanks for taking our questions.

Why don't I take this one, Sean? This is James. So you recall that challenge studies, typically they're more aggressive than what you see in nature, in the real world occurrence of disease. The sample size for this study is built primarily for descriptive statistical analysis, as we're really looking to understand how the vaccine operates.

To do this, we have a number of measures we're looking at, including, but not limited to a decrease in severity of AGE, or acute gastroenteritis, a decrease in viral shedding, effect on infectivity, and effect on disease severity.

Got it. Thanks for taking our questions.

(Operator Instructions) Roger Song, Jefferies.

Great. Thanks for the update and taking our question. A few quick ones from us. So the first one, for the bivalent immunogenicity data in mid-year. So can you just let us know what is the expectations for that data and how you're going to make the go/no-go decision forward? And understanding you will potentially do a Phase 2b, what will be the potential study design for that based on the Phase 2 immunogenicity data you will see in the mid-year? Yeah, I have a follow-up after that. Thank you.

Yeah, Roger. This is James. So I'll take a stab at that. For the Phase 2, our 202 norovirus study, we're looking at the safety and immunogenicity of two different dosage strengths of our bivalent construct. And we'll take a look at both the safety, which to date, knock on wood, is looking just as our portfolio has in the past, well-tolerated.

But we'll also look at immunogenicity and compare those two groups. I think those are the two things we'll look at to judge what dose to take to the larger study, the Phase 2b, so that we can get enough safety data to then have a follow-on discussion and a post-Phase 2 discussion with the FDA. And the follow-on to that study would likely take a few months. So we would project, if all is successful, potentially 2024.

Got you. And then so given you will have the challenger study data from the monovalent in 3Q, as you do the Phase 2b for the bivalent, do you expect you will also do something similar as the challenger study before you move into the pivotal? Or you will bring the bivalent with the larger Phase 2b immunogenicity data with the monovalent challenger data and moving into the Phase 3 pivotal?

Well, I think the sequence of events are such that we'll have the topline data from the 202 study, the Phase 2 dose comparison study Part A, mid-year. As we've said in this conversation, we'll have the topline data for the challenge study in Q3 of this year. So those two data points are fairly important as we map out our next steps.

Does that answer your question, Roger? Because I'm not quite sure if I got that.

Yeah. Just -- I think you answered the question, but just curious do you need another challenge study for your bivalent before you can move into later-stage development?

Yeah. I think that's a discussion to have with the regulatory agencies after we have this data, in terms of additional studies or whether or not that's a requirement or not is something that we'll talk to -- be talking to the agency about.

Got it. Thank you.

Okay, that concludes the audio portion of the Q&A. So I'll now turn it over to Ed Berg for the written Q&A.

Thank you. We've had a number of online questions. James, this first question is for you. Did you have additional discussions with the FDA this quarter? And if so, what was the context of those discussions, if any?

Thanks, Ed. We had not planned for formal discussions with the FDA this past quarter and really haven't had a need for any discussions in the past quarter. But we do plan for a post-Phase 2 meeting with the FDA once the larger Phase 2b study is completed, as I mentioned to Roger.

Thank you. Also on the subject of norovirus, this question is for Sean. How important is identifying correlates of protection to the overall norovirus program? And a follow-up question too, what could identifying those correlates tell you about the vaccine candidate and probability of success in Phase 3?

Thanks, Ed. Yeah. Certainly understanding what immune parameters are reflective of success, it's important for speeding up the clinical development. It helps you know what to look for in late-stage trials and helps you understand that any changes you make in dose and vaccination schedule can positively impact efficacy. Of course, this is not a have to have, but it's certainly nice to have because it can speed up your trial and definitely reduce the size of your -- and your Phase 3 study.

Thanks, Sean. We have one more question on the norovirus program. This one is for James. Would herd immunity have a role for norovirus? If you vaccinate infants, would adults be protected over time?

Yeah, it's an interesting question. It's unknown how norovirus infectivity and spread would be affected by a vaccine because, as you know, there's no currently approved vaccine out there. However, there are several studies that inform us that show that if you vaccinate young children, you also improve the health of adults.

There's a relatively well-known study out of Japan that showed when young children were vaccinated for influenza, the rate of death for all causes -- or all-cause mortality in the elderly population decreased significantly. You might not be able to protect against all illness, but we know that children acquire disease and then transmit to their families. And that's a portion of global health that we hope to address.

Thank you. We have a question -- the next question is on the coronavirus, the COVID program we have and that actually is -- I think, Sean and Andrei, you might want to answer this.

The question is that the Washington Post reported on the Biden administration's RFI for next-generation coronavirus vaccines. And the report referenced a potential $5 billion in funding. Does the Biden administration next-gen vaccine proposal change at all how you're thinking about the pan-betacoronavirus program that you referenced in the call?

Yeah, that's a good question. Again, the reported potential funding for next-generation vaccines is a positive step. I don't think the announcement changes our approach, but it is probably reflective of the consensus of the scientific community that improvements to the current vaccines can be made.

Andrei?

Yeah. And yeah -- what I would add to what Sean said is that we see this progress from the Biden administration as a confirmation of our approach. And as people that have read the RFI can attest, we feel like the requirements and the focus on mucosal immunity fill very well our platform. So we are quite encouraged by these initiatives, and we are looking forward to seeing how we can participate in it.

Thank you, Andrei. One final question. This one's for Sean, again on COVID. Do you have a timeline for advancing a pan-betacoronavirus vaccine candidate to the clinic?

Yeah, I mean, certainly, we are continuing to develop newer candidates in constructs and research, which we believe have increased potential to make a potent pan-betacoronavirus vaccine. We're not providing any guidance at the time. Again, timing depends on multiple factors.

Okay. That's all the questions we have. I'll turn it back over to the operator.

Okay. Thank you. This concludes our call. You may now disconnect and thank you again for joining.