Atea Pharmaceuticals 2026 Q3 Earnings Call

Ms. Barnes, please proceed. Good afternoon, everyone, and welcome to Atea Pharmaceuticals Third 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 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 all 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 risk and uncertainties.

These risk 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 three. During the third quarter, we made significant progress across our pipeline, setting the stage for a milestone-rich 2027. With positive phase III results of our North American trial for the treatment of HCV and the rapid clinical advancement of our phase I HEV program, we are well-positioned to deliver on our commitment to advance potential best-in-class or first-in-class therapies that address the need of people worldwide living with serious viral diseases. CBR, our phase III trial evaluating the bemnifosbuvir regimen for the treatment of HCV in North America, delivered strong results, meeting its primary and secondary endpoints, which of course is a major milestone for Atea. Arantxa Horga will review the results of the trial in more detail.

We are on track to report top-line results in early 2027 for C-FORWARD, which is our global trial that enrolled patients in 17 countries. The results are expected to confirm the efficacy of bemnifosbuvir across a broad range of HCV genotypes. Pending this result, together with C-BEYOND, are expected to support a new drug application submission targeted for mid-2027 with the U.S. FDA. During the quarter, we also initiated a phase I clinical trial in healthy subjects for AT-587, a potential first-in-class direct-acting antiviral for chronic HEV, a serious disease for immunocompromised patients. I am pleased to report that the single ascending dose portion has been completed, and we are progressing in the multiple ascending dose portion. We anticipate advancing AT-587 into a proof-of-concept study in the first half of 2027, with preliminary results targeted for late 2027.

We remain in a very solid financial position with $191.2 million in cash and marketable securities as of September 30, 2026. As announced today, we have entered into a credit facility agreement with Hercules Capital for up to $200 million, drawing down $65 million at closing. The staged financing structure allows us to access capital and strengthen our flexibility in building commercialization robustness as we advance toward the anticipated U.S. launch of bemnifosbuvir in 2028. Andrea will review the details of this new transaction. Moving to slide four, our program boasts a first-in-class potential, and we have now the financial runway to fund them through the major milestones detailed in this slide. Starting with HCV, bemnifosbuvir's potential best-in-class profile combines high cure rates with short treatment durations, low risk of drug-drug interaction, and no food effect. The HCV market remains substantial.

In 2025, global net sales were approximately $2.6 billion, including roughly $1.3 billion in the United States. For the bemnifosbuvir regimen, we see peak U.S. net sales potential of more than $700 million. Turning to HEV, AT-587 is a potential first-in-class direct-acting antiviral. In an at-risk patient population, HEV can lead to chronic infection, cirrhosis, liver failure, or death, and there are no FDA-approved treatments. We estimate a commercial opportunity between $1 billion and $1.5 billion per year in patients with HCV in the United States and Europe. I will now hand the call over to Arantxa Horga, our Chief Medical Officer, to review our phase III program.

Thank you, Jean-Pierre. Good afternoon, everyone. Moving to slide six, C-BEYOND was a randomized, active-controlled, non-inferiority trial against sofosbuvir/velpatasvir, marketed as EPCLUSA, a standard of care regimen. The trial enrolled 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/ruzasvir for eight weeks, or SOF/VEL for 12 weeks. Patients with compensated cirrhosis received 12 weeks of treatment with either regimen. Slide seven outlines the C-BEYOND endpoints and patient populations. The primary efficacy endpoint is sustained viral response, or SVR, at week 24 in the modified intent-to-treat, or mITT, population, as agreed 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 eight, 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 nine, C-BEYOND enrolled a population representative of HCV patients being treated in North America today. Please note that this population is meaningfully different from the population enrolled in clinical trials 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 psychiatric disorders, and over 10% prematurely discontinued treatment, were lost to follow-up, or were not adherent to the protocol. Let's now review the phase III results on slide 10.

In the primary endpoint mITT population, bemnifosbuvir/ruzasvir achieved a 94% SVR rate compared with 95% for SOF/VEL at week 24, encompassing SVR12, the accepted definition of cure for HCV. These results met the primary endpoint of statistical non-inferiority within the pre-specified 5% margin. Bemnifosbuvir/ruzasvir delivered cure rates comparable to the standard of care while offering an eight-week regimen for non-cirrhotic patients, which represent the majority of the patients in North America, compared to 12 weeks of SOF/VEL. On slide 11, in the non-cirrhotic mITT population, bemnifosbuvir/ruzasvir achieved a 94% SVR rate with eight weeks of treatment compared with 95% for SOF/VEL with 12 weeks of treatment. In patients with compensated cirrhosis, both arms achieved a 95% SVR rate with 12 weeks of treatment. Patient subpopulations are not powered for statistical analysis. On slide 12 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 the treatment arms. There were no serious adverse events due to the study drugs. During the treatment-emergent safety observation, treatment-emergent adverse events resulted in death occurred in no patients receiving bemnifosbuvir/ruzasvir and in three patients receiving SOF/VEL. None of these events were related to the study drug. There were no early treatment discontinuations related to the study drugs. Slide 13 outlines the patient population and analysis for C-FORWARD, our second phase III trial being conducted outside of North America to support a broad pan-genotypic label. Building on the positive phase III results from C-BEYOND, we are looking forward to this next important readout in early 2027 and the opportunity to further demonstrate bemnifosbuvir/ruzasvir potential across a broader range of HCV genotypes.

C-FORWARD enrolled more diverse genotypes, 1b, three, four, five, and six, and uses the same non-inferiority methodology and powering assumptions as C-BEYOND. Together, we expect the two phase III studies will form a comprehensive global data package for regulators worldwide. I will now hand over the call to Janet Hammond, our Chief Development Officer.

Thank you, Arantxa. Good afternoon, everyone. Moving on to slide 15, bemnifosbuvir/ruzasvir is a once-daily fixed-dose regimen. bemnifosbuvir is a highly potent HCV nucleotide, and ruzasvir is a highly potent 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 eight-week treatment duration for non-cirrhotic patients, protease inhibitor-free composition, a low potential for drug-drug interactions, and no food effect. That combination is what we believe defines potential best-in-class profile. On slide 16, the drug-drug interaction profile is an important differentiator for bemnifosbuvir/ruzasvir. Roughly 80%-90% of HCV patients in the U.S. take concomitant medications, and prescribers strongly prefer therapies that are simple to prescribe.