C-FORWARD Phase 3 Trial Outside North America for Treatment of HCV on Track to Complete Enrollment Mid-2026; Topline Results Expected Around Year-End 2026
Encouraging Preclinical Data Support AT-587 as a Potential First-in-Class Therapy for Hepatitis E Virus (HEV); Phase 1 Initiation Expected Mid-2026
Company Holding Conference Call Today at 4:30 pm ET
BOSTON, May 12, 2026 (GLOBE NEWSWIRE) -- Atea Pharmaceuticals, Inc. (NASDAQ:AVIR) (Atea or Company), a late-stage clinical biopharmaceutical company engaged in the discovery and development of oral antiviral therapeutics for serious viral diseases, today reported financial results for the first quarter ended March 31, 2026, and provided a business update.
"With two pivotal Phase 3 readouts for our HCV program on the horizon, 2026 will be a catalyst-rich year for Atea," said Jean-Pierre Sommadossi, PhD, Chief Executive Officer and Founder of Atea Pharmaceuticals. "The data generated to date for the regimen of bemnifosbuvir and ruzasvir support a differentiated, potentially best-in-class profile, combining high efficacy, short treatment duration with low risk of drug-drug interactions, and dosing convenience. By simplifying HCV treatment for both patients and providers, our regimen preferentially aligns with the expanding ‘test-and-treat' model of care, which we believe will result in more patients treated and an opportunity to accelerate HCV elimination efforts."
"In parallel, our HEV program underscores our continued commitment to developing antiviral therapeutics for serious viral diseases where significant unmet needs persist. HEV represents a critical gap in care with no approved therapies, leaving vulnerable populations including transplant recipients and other immunocompromised patients at risk for rapid disease progression. Following encouraging preclinical data, we look forward to advancing our potential first-in-class candidate, AT-587, into the clinic mid-year," Dr. Sommadossi added.
Approaching Pivotal Milestones in Phase 3 Program for Potential Best-in-Class HCV Regimen
Atea continues to advance its global Phase 3 program for the treatment of chronic HCV infection. In the Phase 3 program, Atea is comparing the fixed-dose combination (FDC) regimen of bemnifosbuvir (BEM), a nucleotide analog polymerase inhibitor, and ruzasvir (RZR), an NS5A inhibitor, to the FDC regimen of sofosbuvir and velpatasvir. The regimen of BEM/RZR is administered orally once-daily for eight weeks (in patients without cirrhosis) or 12 weeks (in patients with compensated cirrhosis) while the regimen of sofosbuvir and velpatasvir is administered orally once-daily for 12 weeks to all patients, regardless of cirrhosis status.
The global Phase 3 program consists of two open-label, controlled trials:
C-BEYOND (conducted in North America): Enrollment completed in December 2025 with more than 880 patients; topline results expected mid-2026.
C-FORWARD (conducted outside North America): Enrollment on track for completion mid-2026; topline results expected around year-end 2026.
The primary endpoint for each trial is HCV RNA < lower limit of quantitation (LLOQ) at 24 weeks from the start of treatment and encompasses sustained virologic response 12 weeks post-treatment (SVR12) in each arm. Measurement at 24 weeks from the start of treatment is to ensure the primary endpoint measurement occurs at the same relative timepoint from the start of treatment in all patients. The primary endpoint will be assessed in the modified intent-to-treat population in C-BEYOND and in the per-protocol population in C-FORWARD.
Results Support a Differentiated and Competitive Profile for the Treatment of HCV
Results from Atea's Phase 2 clinical study, together with results from other preclinical and clinical studies, continue to support a differentiated profile for BEM/RZR. In the Phase 2 study, the 8-week regimen achieved 98% SVR12 in the per-protocol, treatment-adherent population and 95% SVR12 in the efficacy-evaluable population. Additional preclinical and clinical studies have supported a high barrier to resistance, dosing convenience with or without food, co-administration with H2-blockers, a low risk of clinically meaningful drug-drug interactions, and no need for dose adjustment of BEM in patients with hepatic or renal impairment. Results from recent studies demonstrated a low risk of drug–drug interactions with proton pump inhibitors and statins. Atea notes this is particularly significant, as its market research indicates that up to 80% of patients infected with HCV take at least one concomitant medication with proton pump inhibitors and statins being among the most common.
Last year, Atea presented data supporting a potentially differentiated antiviral mechanism of action. BEM has an established mechanism of inhibition of HCV RNA leading to chain termination, blocking viral production and replication inside the host cell. However, modeling of HCV viral kinetics from a Phase 1b study suggests that BEM may also inhibit the assembly/secretion of new HCV virions into the bloodstream. These data may further explain the high antiviral potency of BEM/RZR.
Atea believes that collectively, these product attributes and study results position BEM/RZR competitively within the evolving HCV landscape. This is particularly relevant as the ‘test-and-treat' model of care, which enables rapid diagnosis and treatment initiation at the point of care, is increasingly adopted by healthcare providers and supported by stakeholders as critical to HCV elimination efforts. HCV remains a significant global healthcare burden, affecting as many as four million people in the United States (US), according to the CDC.
Preclinical Results Presented at the Conference on Retroviruses and Opportunistic Infections (CROI) 2026 Support AT-587 as a Potential First-in-Class Therapy for HEV
In 2025, Atea strategically expanded its pipeline to target hepatitis E virus (HEV), for which no approved therapies currently exist. If successful, the HEV program could address a substantial unmet medical need for immunocompromised patients and other high-risk populations, such as transplant recipients, for whom HEV is a serious disease that can rapidly progress to cirrhosis.
At CROI 2026, Atea presented in vitro data showing that two drug candidates, AT-587 and AT-2490, were potent inhibitors of HEV replication. The compounds were reported to be 30- to 150-fold more potent against HEV than either sofosbuvir or ribavirin, active against all flaviviruses tested as well as rubella and chikungunya, and associated with high levels of active metabolite formation in human liver cells. Neither compound showed toxicity in the reported studies. Atea selected AT-587 as the lead product candidate and anticipates initiating a Phase 1 clinical program for AT-587 in mid-2026.
First Quarter 2026 Financial Results
Cash, Cash Equivalents and Marketable Securities: $256.0 million at March 31, 2026, compared to $301.8 million at December 31, 2025.
Research and Development Expenses: Research and development expenses increased by $11.6 million from $29.6 million for the three months ended March 31, 2025, to $41.1 million for the three months ended March 31, 2026. The net increase was partially driven by an increase in external spend for our HCV Phase 3 clinical development and HEV preclinical development. The increase was partially offset by lower internal research and development expenses primarily related to lower salaries and wages and lower stock-based compensation for the three months ended March 31, 2026.
General and Administrative Expenses: General and administrative expenses decreased by $2.6 million from $9.5 million for the three months ended March 31, 2025, to $6.9 million for the three months ended March 31, 2026. The net decrease was primarily related to lower salaries and wages, lower stock-based compensation and lower professional fees for the three months ended March 31, 2026.
Interest Income and Other, Net: Interest income and other, net, decreased by $2.4 million for the three months ended March 31, 2026, compared to the three months ended March 31, 2025, primarily due to lower investment balances.
Income Taxes: Income tax expense was $0.1 million for the three months ended March 31, 2026, compared to $0.2 million for the three months ended March 31, 2025.
Condensed Consolidated Statement of Operations and Comprehensive Loss(in thousands, except share and per share amounts)(unaudited)
Three Months EndedMarch 31,
