SVR12 in combination of bemnifosbuvir and ruzasvir - (C-BEYOND)

May 12, 2026: Atea Pharmaceuticals, Inc. (NASDAQ: AVIR) reported Q1 2026 results and provided a pipeline update highlighting upcoming Phase 3 catalysts for its oral hepatitis C virus (HCV) regimen bemnifosbuvir (BEM) + ruzasvir (RZR) and preclinical progress in hepatitis E virus (HEV).

HCV (BEM/RZR fixed-dose combination): A global Phase 3 program is comparing BEM/RZR vs sofosbuvir/velpatasvir in two open-label controlled trials. C-BEYOND (North America) completed enrollment in December 2025 with >880 patients; topline results are expected mid-2026. C-FORWARD (outside North America) is on track to complete enrollment mid-2026, with topline results expected around year-end 2026. Primary endpoint in both trials is HCV RNA < LLOQ at 24 weeks from start of treatment (aligning with SVR12 timing), assessed in modified ITT (C-BEYOND) and per-protocol (C-FORWARD). The company cited Phase 2 SVR12 of 98% (per-protocol, adherent) and 95% (efficacy-evaluable) for an 8-week regimen.

HEV (AT-587): At CROI 2026, Atea presented in vitro data that AT-587 and AT-2490 inhibited HEV replication and were reported 30–150x more potent than sofosbuvir or ribavirin, with no toxicity observed in the reported studies. Atea selected AT-587 as lead and expects to initiate Phase 1 mid-2026.