Atea Pharmaceuticals, Inc. Common Stock 2026 Q2 Earnings Call

Good afternoon, everyone, and welcome to Atea Pharmaceuticals' second quarter 2026 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 Investors section of our website at ir.ateapharma.com. With me from Atea, are our 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, 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 2, 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.

Thank you, Jonae. Good afternoon, everyone, and thank you for joining us. I will begin on slide 3. The positive top-line results from C-BEYOND, our phase III trial evaluating the combination of bemnifosbuvir for the treatment of Hepatitis C in North America represent a significant milestone for Atea and for the millions of people living with Hepatitis C who need a shorter, simpler path to cure. We were very pleased that C-BEYOND met both its primary and secondary endpoints, with bemnifosbuvir demonstrating statistical non-inferiority to EPCLUSA, the current standard of care. Importantly, this was the first successful phase III trial in the global head-to-head HCV program, achieved in the real-world patient population that was poly-medicated, psychiatrically complex, substance abuse affected, and adherence challenged. These results reinforce the need for a best-in-class profile designed for the broad and complex Hepatitis C population clinicians treat today.

Arantxa will review in details the results of the trial. C-FORWARD, our second phase III trial being conducted outside North America, is fully enrolled with more than 880 patients, and we remain on track to report top-line results in early Q1 2027. We believe that the C-FORWARD data set will provide important confirmatory efficacy data across a broader range of genotypes and strengthen the pan-genotypic regulatory package for bemnifosbuvir. In July, we also initiated our first in-human phase I clinical trial of AT-587, our potential first-in-class direct-acting antiviral for chronic Hepatitis E, a serious disease with no approved therapy to date. This milestone reflects the continued advancement of our all direct-acting antiviral pipeline. We remain in a solid financial position, with $219.5 million in cash and marketable securities as of June 30, 2026, with our cash runway anticipated through 2027.

I will now hand the call over to Arantxa, our Chief Medical Officer, to review our phase III program.

Thank you, Jean-Pierre, and good afternoon, everyone. Moving to slide 5, C-BEYOND was a randomized active control non-inferiority trial against sofosbuvir/velpatasvir, marketed as EPCLUSA, a standard of care regimen. The trial involved patients with chronic HCV at approximately 120 clinical sites in the U.S. and Canada, including patients co-infected with HIV and patients across the HCV genotypes that predominate in North America. Patients without cirrhosis received bemnifosbuvir for 8 weeks or SOF/VEL for 12 weeks. Patients with compensated cirrhosis received 12 weeks of treatment with either regimen. On slide 6, let's now review the C-BEYOND endpoints and patient populations. The primary efficacy endpoint is SVR or cure at week 24, assessing the modified intent to treat, or MITT population, which was agreed upon with the FDA.

This population includes all patients who received at least one dose of the regimen, including those who discontinued early, were not compliant, or were lost to follow-up. The trial is powered at 90% with a 5% non-inferiority margin. C-BEYOND is the anchor trial for the U.S. NDA submission. Moving to slide 7, you can see that the baseline characteristics of the patients in C-BEYOND were very well-balanced across the two arms, including age, sex, BMI, race and ethnicity, cirrhosis status, viral load, and HIV co-infection. On slide 8, C-BEYOND enrolled the HCV population clinicians are treating in North America today, which looks meaningfully different from the population studied a decade ago. In our trial, more than half of the patients reported injection drug use as the root of HCV transmission. Approximately 89% were taking concomitant medications.

Two-thirds had a psychiatry disorder, and over 10% prematurely discontinued treatment, were lost to follow-up, or were not adherent to the protocol. Current standard of care regimens have challenges where it matters most. A moderate protease inhibitor-containing regimen carries DDI limitations that restrict or complicate use in many of these patients, while EPCLUSA requires 12 weeks of treatment. In our market research, only 6% of 157 high-prescribing U.S. physicians reported no unmet need, with physicians continuing to cite key priorities such as shorter duration, high efficacy, and fewer contraindications. Let's now review the phase III results on slide 9. In the primary endpoint MITT population, bemnifosbuvir achieved a 93.9% SVR rate, compared with 94.8% for SOF/VEL at week 24, encompassing SVR12, the accepted definition of cure for HCV. This result met the primary endpoint of statistical non-inferiority within the pre-specified 5% margin.

bemnifosbuvir delivered cure rates comparable to the standard of care while offering an 8-week regimen for non-cirrhotic patients, compared to 12 weeks for SOF/VEL. On slide 10, in the non-cirrhotic MITT population, bemnifosbuvir achieved a 93.5% SVR rate with 8 weeks of treatment, compared with 94.6% for SOF/VEL with 12 weeks of treatment. In patients with compensated cirrhosis, both arms achieved a 95.4% SVR rate with 12 weeks of treatment. Patients of populations are not powered for statistical analysis. On slide 11 is the safety summary. Overall, adverse events were comparable between the two treatment arms. Most treatment-emergent adverse events were mild to moderate and balanced between treatment arms. There were no serious adverse events due to the study drugs, and while there were no deaths in the bemnifosbuvir arm, 3 deaths in the SOF/VEL arm were observed, but not related to the study drug.

Similarly, there were no early treatment discontinuations related to the study drugs. Moving to slide 12, real-world adherence and discontinuation of treatment with loss to follow-up remains a major barrier in HCV treatment today and helps explain why current SVR rates with approved therapies can fall below the rates reported 10 years ago in the original pivotal studies. Indeed, as you can see in more recent studies, the intent to treat SVR rates fall below the rates reflected in labels established a decade ago, including rates as low as 74% among people who injected drugs with rates consistently in the low 90s. Slide 13 summarizes the top-line results for C-BEYOND. The trial met its primary and secondary endpoint, with bemnifosbuvir demonstrating consistent SVR rates regardless of cirrhosis status and robust performance across genotypes. Virological failure rates were low and comparable across treatment arms.

bemnifosbuvir was generally safe and well-tolerated, with a safety profile comparable to SOF/VEL. On slide 14 is the patient populations and analysis for C-FORWARD, our second phase III trial being conducted outside of North America to enable a broad pan-genotypic label. It is fully enrolled and enriched for genotypes 1b, 3, 4, 5, and 6, using the same non-inferiority methodology and the same powering assumption. Together, the two phase III studies will form a comprehensive global data package for regulators worldwide. I will now hand the call over to Janet, our Chief Development Officer.

Thank you, Arantxa. Good afternoon, everyone. Moving on to slide 16. bemnifosbuvir/ruzasvir is a next generation pan-genotypic, once daily, six dose regimen. bemnifosbuvir is the most potent nucleotide we are aware of, being approximately 10-fold more active than sofosbuvir in vitro. ruzasvir is a picomolar potency pan-genotypic NS5A inhibitor. Together, they have been administered to thousands of individuals with generally favorable safety and tolerability. Compared with EPCLUSA and MAVYRET, bemnifosbuvir/ruzasvir is the only regimen positioned to offer the full combination of short, 8-week duration for non-cirrhotic patients, protease inhibitor-free composition, low potential for drug-drug interactions, and no food effect. That combination is what defines a potential best-in-class profile. On slide 17, the drug-drug interaction profile is a key differentiator for bemnifosbuvir/ruzasvir. Roughly 80%-90% of Hepatitis C patients in the U.S. take concomitant medications, and prescribers strongly prefer therapies that are simple to prescribe.

Across the classes of oral contraceptives, protease inhibitors, and integrase inhibitor HIV regimens, statins, immunosuppressants, digoxin, and proton pump inhibitors, and other acid-reducing therapies, bemnifosbuvir/ruzasvir is expected to be broadly compatible where competitors carry contraindications or require dose modifications. Fewer drug interactions, fewer specialist referrals, fewer treatment delays, and more patients actually starting and completing therapy. Today's treatment challenge is less about efficacy and more about treatment duration, adherence, drug-drug interactions, and access. Based on the potential profile of bemnifosbuvir/ruzasvir, we believe our regimen is well-positioned to address these barriers and expand the number of patients successfully treated. I'll now turn the call over to John Vavricka, our Chief Commercial Officer.