Atea Pharmaceuticals Fourth Quarter 2025 Earnings Call - Phase 3 HCV readouts set to define 2026 with cash runway through 2027

Operator: Good afternoon, everyone, welcome to the Atea Pharmaceuticals Fourth Quarter 2025 Financial Results and Business Update Conference Call. At this time, all participants are in a listen-only mode. Following the formal remarks, we will open up the call for your questions. I would now like to turn the call over to Jonae Barnes, Senior Vice President of Investor Relations and Corporate Communications at Atea Pharmaceuticals. Ms. Barnes, please proceed.

Jonae Barnes, Senior Vice President of Investor Relations and Corporate Communications, Atea Pharmaceuticals: Great. Thank you, operator. Good afternoon, everyone. Welcome to Atea Pharmaceuticals fourth quarter and full year 2025 financial results and business update conference call. Earlier today, we issued a press release which outlines the topics we plan to discuss. You can access the press release as well as the slides that we’ll be reviewing today by going to the investor section of our website at ir.ateapharma.com. With me today from Atea are Chief Executive Officer and Founder, Dr. Jean-Pierre Sommadossi; Chief Development Officer, Dr. Janet Hammond; Chief Commercial Officer, John Vavricka; Chief Medical Officer, Dr. Arantxa Horga; and Chief Financial Officer and Executive Vice President of Legal, Andrea Corcoran, who will be available for the Q&A portion of today’s call.

Before we begin the call, and as outlined on slide two, I would like to remind you that today’s discussion will contain forward-looking statements that involve risks and uncertainties. These risks and uncertainties are outlined in today’s press release and in the company’s recent filings with the Securities and Exchange Commission, which we encourage you to read. Our actual results may differ materially from what is discussed on today’s call. With that, I’ll now turn the call over to Jean-Pierre.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Thank you, Jenna. Good afternoon, everyone, and thank you for joining us. I will begin on slide 3. I am pleased to report that we have made substantial clinical progress in the last year, advancing our global phase 3 program, evaluating the regimen of bemnifosbuvir and ruzasvir for the treatment of HCV infections. Due to the rigorous execution of our two pivotal phase 3 trials, C-FORWARD and C-BEYOND, we expect top-line readouts this year for both trials. We also presented several datasets reinforcing the potential best-in-class profile of our regimen at the EASL Congress in 2025 and The Liver Meeting 2025, the annual meeting of AASLD. Janet will discuss highlights from these presentations.

We convened two panel discussions with key opinion leaders that underscore the need for a new optimized HCV regimen to address treatment paradigm shifts, including the test and treat model of care, and how our regimen is uniquely positioned to address the current needs of patients and prescribers and expand the market in the U.S. In November, we announced the expansion of our antiviral Hepatitis pipeline to address a major unmet medical need for immunocompromised patients living with chronic Hepatitis E infection, a liver disease for which there is currently no approved therapy available. If left untreated, it can rapidly progress to cirrhosis within 3-5 years. In vitro and in vivo results presented last month at CROI 2026 and at the J.P. Morgan Healthcare Conference in January support our lead product candidate, AT-587, as a potential first-in-class inhibitor against HEV infection.

I will review this exciting program later in the presentation. Moving to slide 4, I’m pleased to report that our global phase 3 HCV program is on track. In December, we completed enrollment for our North American trial, C-BEYOND, with over 880 patients, and we expect to complete enrollment C-FORWARD, our trial outside of North America, by midyear. We anticipate top-line results for C-BEYOND midyear and for C-FORWARD by year-end. Following our selection of AT-587 as the lead product candidate in our HEV program, we initiated IND and CTA enabling studies and anticipate initiating a first-in-human study midyear. Importantly, with $301.8 million of cash equivalent and marketable securities as of December 31, 2025, we are in a strong financial position to execute and complete our phase 3 HCV program and advance our new HEV development program.

We anticipate our cash runway will extend through 2027. With that, I will now turn the call over to Janet to review the profile of our regimen.

Dr. Janet Hammond, Chief Development Officer, Atea Pharmaceuticals: Thanks, Jean-Pierre. Moving to slide 6. Hepatitis C remains a significant global healthcare crisis, with an increasing incidence of infections despite the availability of direct-acting antivirals for the past decade. Currently in the United States, out of the reported 160,000 new chronic infections, only 85,000 patients are treated annually. In 2015, there were approximately 2.5 million people infected in the United States. Today, that number has nearly doubled to approximately 4 million. The unrelenting high rate of new chronic Hepatitis C infections, which continues to outpace the number of patients being treated, underscores the need for a new differentiated and optimized therapy. In the map shown on the right, you can see that most countries worldwide, including the United States, are not on track to achieve the World Health Organization’s goal of the elimination of Hepatitis C by 2030.

In fact, current estimates suggest we may not even achieve this goal by 2050. Let’s not forget that Hepatitis C is the primary cause of liver cancer in the United States. The incidence of which is projected to increase by over 50% within the next 5 years from approximately 850,000 cases in 2025 to 1.4 million people. On slide 7, we’re conducting the first global head-to-head active controlled phase 3 trials in our program for Hepatitis C, comparing our regimen against the current standard of care, sofosbuvir and velpatasvir, which are marketed as Epclusa. Results support our regimen as a potential best-in-class treatment option for patients infected with HCV, with a differentiated profile featuring a highly potent combination with a short treatment duration, low risk for drug-drug interactions, and convenience with no food effects.

We continue to build out our data set, and recent results demonstrated a low risk for drug-drug interactions with proton pump inhibitors, which are taken by an estimated 35% of Hepatitis C-infected patients. Moving to slide 8. We’ve presented several data sets supporting the potential best-in-class profile of the regimen of bemnifosbuvir and ruzasvir last year at the EASL Congress and then at The Liver Meeting. Results from the phase 2 study in 275 patients demonstrated the 8-week regimen of bem/ruzasvir achieved 98% SVR12 in the protocol treatment-adherent population, and a 95% SVR12 in the efficacy-evaluable population. Additional results demonstrated that the regimen has a high barrier to resistance. The regimen has a low risk for drug-drug interactions, including with proton pump inhibitors, H2 blockers, and also standard HIV therapy.

There is no need for dose adjustment of bemnifosbuvir in patients with hepatic or renal impairment. The regimen can be taken with or without food. In addition, recently generated data show that in addition to inhibiting HCV RNA replication through chain termination, bemnifosbuvir also inhibits assembly and secretion of new Hepatitis C virions, further explaining its high antiviral potency. With that, I’ll now turn the call over to Arantxa to provide an update on our phase 3 program for Hepatitis C. Arantxa?

Dr. Arantxa Horga, Chief Medical Officer, Atea Pharmaceuticals: Thank you, Janet. On slide 10, C-BEYOND enrolled patients in the U.S. and Canada, and C-FORWARD is enrolling patients in 17 countries outside of North America. Combined, we expect to enroll more than 1,760 patients in our phase 3 program. Both trials are open-label, randomized 1-to-1 against the active comparator and stratified by cirrhosis status, genotype, and including patients co-infected with HIV. In patients without cirrhosis, treatment duration is 8 weeks with bemnifosbuvir/ruzasvir and 12 weeks with the standard of care. Patients with compensated cirrhosis receive 12 weeks of treatment with either regimen. The primary endpoint for both studies is sustained viral response or cure 24 weeks after treatment initiation.

Slide 11 shows the geographic footprint of our global phase 3 program with approximately 120 clinical sites in the U.S. and Canada for C-BEYOND and another 120 clinical sites in 17 countries outside of North America for C-FORWARD. As JP mentioned earlier, C-BEYOND patient enrollment was completed in December with more than 180 patients. We anticipate top-line results mid-year. C-FORWARD has a broader global geographic and genotypic footprint. We expect to complete enrollment mid-year and to report top-line results by year-end. On slide 12, let’s review the phase 3 endpoints, patient population, and data analysis for our global phase 3 program. In C-BEYOND, the primary endpoint will be analyzed in a modified intent-to-treat population as preferred by the U.S. FDA. The analysis will include patients that have been randomized and dosed regardless of drug adherence or loss to follow-up.

The statistical analysis will be based on an imputation model with success or failure depending on PCR value, whether negative or not, prior to patient treatment discontinuation. A key secondary endpoint will include the SVR rate of the per-protocol population. In C-FORWARD, the per-protocol population will be analyzed as the primary endpoint as preferred by the EMA. The SVR rate will only include patients who are at least 80% adherent as measured by pill count and have an SVR assessment at week 24. A key secondary endpoint will include the SVR rate for a modified intent to treat population. The same methods for assessing non-inferiority will be conducted in both phase 3 studies and both patient populations. The phase 3 studies are powered 90% with 5% non-inferiority margin, with expected rates approximating 95% in an MITT population.

Using these two approaches in a post-hoc analysis of the phase 2 results, the SVR rate was 95% in an MITT population and 98% in the per protocol population. I will now hand the call over to John Vavricka, our Chief Commercial Officer. John?

John Vavricka, Chief Commercial Officer, Atea Pharmaceuticals: Thank you, Raja. Moving on to slide 14. As discussed earlier in the call, the rate of newly reported HCV infections in the U.S. is outpacing treatment. Out of approximately 160,000 new HCV infections, only 85,000 patients are treated annually, for a total of approximately $1.3 billion in net sales in the U.S. We have consistently heard from healthcare providers that the test and treat model of care, which allows for HCV testing, diagnosis and treatment at the point of care, can reduce the barriers to prompt initiation of therapy that exists today. The test and treat model of care has gained broad support, including by the CDC, and continues to gain momentum through recent bipartisan efforts to advance HCV elimination in the U.S.

Key opinion leaders also assert it can play a critical role in HCV elimination efforts and agree that a treatment optimized to work seamlessly with this model is still needed. Slide 15. While we are advancing our global phase 3 trials, we are also preparing for a commercial product launch. Our commercial package will include a blister card for convenience and adherence with a simple 4-week dosing package. The drug product has a low cost of goods relative to net price, and based on our current projections, we anticipate achieving profitability relatively shortly post-launch. From a commercial standpoint, the U.S. HCV prescriber base is highly concentrated with approximately 6,000 prescribers writing 80% of the DAA prescriptions, making it optimal for efficient commercialization using a focused specialty sales force. We anticipate a commercial sales force of around 75 people, which includes the sales team and medical science liaisons.

Let’s move on to slide 16. Using our phase 2 results, IQVIA conducted an independent quantitative market research study with 153 U.S. high prescribers. These physicians indicated that they would likely prescribe the BEM/RZR regimen to approximately half of their patients, and the results were similar for all patients, regardless of their cirrhosis status. Our market research also showed that U.S. payers respond favorably about the potential to include BEM/RZR on the formulary based on the regimen’s profile. I’ll now hand the call back to Jean-Pierre to review the HEV programs.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Thank you, John. Let’s now move to slide 18. Hepatitis E virus or HEV is an acute and a chronic liver disease. In developing countries, genotype 1 and 2 are most prevalent, and the virus is transmitted primarily through contaminated water and mostly cause epidemics of acute self-limiting viral hepatitis. In developed countries, genotype 3 is predominantly transmitted primarily through contaminated food, such as undercooked meat. This can cause chronic hepatitis in immunocompromised patients and can progress to cirrhosis within 3 to 5 years, which is much far more aggressive than what is seen with Hepatitis C or Hepatitis B. With no approved therapies for HEV, there is a significant unmet need for a treatment option. Moving to slide 19.

In recent years, with the increasing number of patients who are immunocompromised, which include solid organ transplant recipients, hematopoietic cell, stem cell transplant recipients, patients with hematologic malignancies such as multiple myeloma, there have been a growing incidence of chronic HCV infection in the U.S. and Europe. In the absence of any approved therapies for HEV, the standard of care includes reducing immunosuppression and/or ribavirin administration, which both presents challenges. On slide 20. Each year in the U.S. and Europe, about 3% or approximately 450,000 patients who have these underlying medical conditions are at risk to develop chronic HEV. We estimate that the unmet need for this patient population represent a market opportunity between $750 million-$1 billion per year. Obviously, this will follow on orphan designation.

On slide 21, let’s now review data supporting the selection of AT-587, our lead product candidate, a potential first-in-class direct-acting antiviral treatment option for chronic HEV. As you see on this slide, in vitro and in vivo activity of bemnifosbuvir was shown against Hepatitis E. However, the more potent in vitro activity of AT-587 combined with the positive PK data, which we’ll discuss next, led us to select AT-587 as the lead product candidate. The in vitro data on this slide shows the potent nanomole antiviral activity of AT-587 against HEV genotype 3, and they remain also active against clinical ribavirin resistance-associated substitutions or RAS. As noted earlier, ribavirin is off-label for the treatment, is used off-label for the treatment of HEV.

On slide 22, we observed that the in vivo single-dose PK studies in rats and monkeys, AT-587 achieved high plasma concentration of the active triphosphate metabolite surrogate, which were comparable to those obtained with bemnifosbuvir. On slide 23, of particular importance, we also demonstrated that AT-587 efficiently converted to its active triphosphate metabolite in human hepatocytes, which is the site of viral replication in HEV infection. To date, AT-587 has a clean preclinical safety profile, positioning this product candidate as a first-in-class direct-acting antiviral for chronic HEV. I will now turn the call over to Andrea to discuss Atea financials.

Andrea Corcoran, Chief Financial Officer and Executive Vice President of Legal, Atea Pharmaceuticals: Thanks, Jean-Pierre. As Sherne mentioned in her introductory remarks, earlier today we issued a press release containing our financial results for the fourth quarter and full year 2025. The statement of operations and balance sheet are on slides 25 and 26. We are pleased to report that our cash and investments were $301.8 million at December 31, 2025. The funds expended in 2025 were principally directed to the advancement of our HCV Phase 3 program, evaluating the combination regimen of bemnifosbuvir and ruzasvir, and to discovery efforts leading to the nomination in January 2026 of AT-587 as the lead product candidate for the treatment of HEV. In 2025, we also returned $25 million to our stockholders through a share repurchase program.

Each of these investments and use of funds reflects our steadfast commitment to drive value for our stockholders. For R&D expenses quarter-over-quarter and year-over-year, there was an increase in 2025 compared to 2024. The net increase in 2025 was principally driven by an increase in external spend for our HCV phase 3 clinical development, offset by a decrease in 2025 in external spend for our COVID-19 clinical development and lower internal expenses, primarily related to a decrease in stock-based compensation expense and lower payroll and payroll-related expenses. For G&A expenses quarter-over-quarter and year-over-year, expenses decreased. The net decrease was primarily related to lower stock-based compensation expense, partially offset by increased professional fees. For 2026, we intend to maintain our rigorous financial discipline while remaining laser-focused on execution and value-creating advancement of our HCV and HEV product candidates.

As we complete our Phase 3 clinical trials, prepare to submit our regulatory filings, and engage in pre-launch activities, including the manufacturing of commercial launch supply, the substantial majority of our spending in 2026 will be focused on the advancement of our HCV program. With the resources in hand as of the end of the year, we expect to realize value-creating milestones for both programs and project our cash runway to extend through 2027. I’ll now hand the call back to Jean-Pierre for closing remarks.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Thank you, Andrea. On slide 27, in closing, 2026 will be a pivotal year for Atea. We are on track to deliver top-line phase 3 results from C-BEYOND mid-year. These results will be followed by the top-line results from C-FORWARD by the end of this year. We believe that the target profile of our regimens featuring high efficacy, short treatment duration, low risk of drug-drug interaction, convenience with no food effect will uniquely position us to address the need of today’s patients and seamlessly fit in the test and treat model of care, which has the potential to bring us closer to the ultimate goal of HCV eradication. Our HEV program represents a strategic expansion of our antiviral pipeline and address a major unmet need in a highly vulnerable patient population for which there is no approved treatment available.

We anticipate initiating a first human study midyear, with the proof of concept by the end of the year and possible to advance to a phase 2, 3 trial in the second half of 2027. With that, I will turn the call back over to the operator.

Operator: Thank you. We will now begin the question and answer session. To ask question, you may press star and then one on your touchtone phone. If you are using a speakerphone, please pick up your handset before pressing the keys. If at any time your question has been addressed and you would like to withdraw your question, please press star and then two. The first question will come from Maxwell Skor with Morgan Stanley. Please go ahead.

Selena, Analyst (covering for Max Skor), Morgan Stanley: Hello, this is Selena on for Max. Having achieved your enrollment target for the cirrhotic population for C-BEYOND, does that increase your confidence in hitting your target in C-FORWARD?

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Arantxa?

Dr. Arantxa Horga, Chief Medical Officer, Atea Pharmaceuticals: We are going to achieve our target overall for the program, both in C-BEYOND and C-FORWARD. The cirrhotic enrollment has not been an issue.

Selena, Analyst (covering for Max Skor), Morgan Stanley: Thank you.

Operator: The next question will come from Jonathan Miller with Evercore ISI. Please go ahead.

Jonathan Miller, Analyst, Evercore ISI: Hi, guys. Thanks so much for taking my question. As we look forward to a commercial launch in HCV, I guess I’ll focus there. Can you talk a little bit about how the commercial landscape is currently organized in terms of contracting? Are there centralized groups that you’re gonna have to convince to switch over from legacy systems? How is pricing in the commercial universe currently going to evolve, as we’ve seen the legacy regimens get put under significant pricing pressure? Can you talk a little bit about how the commercial landscape has evolved over the past 6, 9 months, and how well you’re positioned to deal with those changes?

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Great question, John. John?

John Vavricka, Chief Commercial Officer, Atea Pharmaceuticals: As you know, the distribution market for specialty DAA is a specialty market, and there are 3 segments, pretty much commercial, Medicare, and Medicaid. All of those current distribution pathways are known and are fully utilized, and we’re currently looking at all those relative to the 3 segments, as well as relative to the payers. It’s a known quantity where we will have to be. We actually have conducted preliminary research with the payers and obviously seeing the profile, it is of interest to them, and it was stated that they would be eager to include it in a formulary. As far as for pricing goes, the pricing, you know, it’s relatively stable.

Year-over-year, Madron pricing went up a little bit, inclusive pricing, net pricing did go down. Overall, for the past, you know, at least 2 or 3 years, the relative overall net pricing has been relatively stable, and their market shares are getting pretty close to a 50/50 with the favoring Epclusa. Does that answer your question?

Jonathan Miller, Analyst, Evercore ISI: Yes, it does. Thank you very much. Yeah, I’ll get back in queue. Thanks.

Operator: The next question will come from Andy Hsieh with William Blair. Please go ahead.

Andy Hsieh, Analyst, William Blair: Thanks for taking our question. Looking at the primary endpoint of C-BEYOND based on the modified to the 10 to 2 population, am I thinking about this correctly that based on this analysis plan, you can actually really expand the effect size because you can basically magnify a regimen that you actually can have flexibility into, you know, missing doses and, you know, given the more potency profile compared to the standard of care? That’s part number one. Part number two is, you know, in a scenario where you can actually show material clinical benefit over the standard of care, say maybe with a statistical perspective, John, based on your market analysis, how would that change some of the physician response in terms of, you know, their excitement or potential market uptake? Thank you.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Good question, Andy. Arantxa, you want to try the first one?

Dr. Arantxa Horga, Chief Medical Officer, Atea Pharmaceuticals: Yeah. Andy, the MITT, as you know, is everybody that gets a dose, you know. There will be a range there from people that will get one dose or maybe five days of dosing to people who will be Almost done with the full picture, so we saw all the doses. I think it will be interesting to see how it pans out. You know, what’s the minimum, I guess. Right now we’re really aiming for an eight-week regimen. We can do sub-analysis in the future.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: John?

John Vavricka, Chief Commercial Officer, Atea Pharmaceuticals: We’re, you know, we’re actually very excited because when we look at the market research that has been done just with the phase 2 data, bearing in mind that these physicians had 10 years’ experience with 2 DAAs and showing them a profile and which as we talked about, you know, the short duration, low likelihood of drug-drug interactions and the convenience of with or without food. You know, just seeing that profile for the first time, they saw it being used in approximately 50% of their patients, regardless of their cirrhosis status. The profile right now stands to very well. Your question about if there was some kind of a more favorable response in terms of VEMURZYR, obviously that would play into their likelihood to prescribe VEMURZYR.

We’re also very conscious that we play in the specialty arena. In that specialty arena, you know, obviously the distribution of market share tends to balance itself out to make sure that the market is preserved over time.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Just to add, Andy, it’s clear from the KOL and the prescriber that number 1, key important feature is the treatment duration. Treatment duration definitely will be on the shortest with MARIVAD. After, when you evaluate all the, I would say, complex aspects with patients with polymedication, we feel that the prescriber will really highly favor our regimen. Then we’ll see the, we have to wait the clinical data, you know, in term of all the type of side effects with fatigue and nausea and headaches that have been reported. Let’s not forget, this is the first head-to-head.

There is a lot of world type studies, but as a control randomized clinical study, this is the first one and let’s see what we are going to learn.

Andy Hsieh, Analyst, William Blair: Great. Maybe a quick housekeeping item, just, you know, from an R&D perspective, seems like there is a one-time Merck license agreement. Can you talk about that just so-.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Sure.

Andy Hsieh, Analyst, William Blair: we have a better sense of, you know, kind of going forward with the-

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: Okay, sure. Andrea?

Andrea Corcoran, Chief Financial Officer and Executive Vice President of Legal, Atea Pharmaceuticals: Yes, Andy. We have in-licensed ruprezvir, which is the combination product with bemnifosbuvir in the HCV product candidate. We are paying milestones, and we will pay royalties to Merck on successful commercialization. The next milestone will be due when we submit the NDA and the NDA is approved. We believe that’s in 2027.

Andy Hsieh, Analyst, William Blair: I see. That’s helpful. Thank you.

Operator: This concludes our question-and-answer session. I would like to turn the conference back over to Jean-Pierre Sommadossi for any closing remarks.

Dr. Jean-Pierre Sommadossi, Chief Executive Officer and Founder, Atea Pharmaceuticals: thank you all for joining our fourth quarter 2025 and full year earnings conference call, thank you for your continued support.

Operator: The conference has now concluded. Thank you for attending today’s presentation. You may now disconnect.