Topline results were announced from a phase 3 trial evaluating a fixed-dose combination of bemnifosbuvir, a nucleotide analog polymerase inhibitor, and ruzasvir, an NS5A inhibitor, for the treatment of chronic hepatitis C virus (HCV) infection.

In the C-BEYOND study (ClinicalTrials.gov Identifier: NCT06868264), adults with chronic HCV were randomly assigned to receive oral bemnifosbuvir-ruzasvir (BEM/RZR) once daily (8 weeks for those without cirrhosis or 12 weeks for those with compensated cirrhosis) or oral sofosbuvir-velpatasvir (SOF/VEL; Epclusa^®) once daily for 12 weeks.

The primary endpoint was the proportion of patients achieving HCV RNA below the lower limit of quantitation (LLOQ) at study week 24, representing sustained virologic response 12 weeks posttreatment (SVR12).

In the modified intent-to-treat (mITT) population, BEM/RZR demonstrated statistical noninferiority compared with SOF/VEL for the primary endpoint. The SVR12 rates for BEM/RZR vs SOF/VEL at week 24 were as follows:

• Overall population (cirrhotic and noncirrhotic; N=905): 93.9% vs 94.8%;
• Patients without cirrhosis (n=721): 93.5% vs 94.6%; and
• Patients with cirrhosis (n=184): 95.4% vs 95.4%.

Across all study cohorts, rates of virologic failure (a secondary endpoint) were reported to be low and comparable between the treatment groups. 

“Achieving these high cure rates with just 8 weeks of BEM/RZR in patients without cirrhosis, alongside a favorable drug-drug interaction profile and the flexibility to be taken with or without food, is a meaningful step forward for HCV care,” said Eric Lawitz, MD, Clinical Professor of Medicine at UT Health San Antonio and the Texas Liver Institute. “A shorter, simpler regimen has the potential to streamline prescribing decisions and accelerate the test-and-treat strategies that are essential to HCV elimination.” 

The combination of BEM/RZR vs SOF/VEL is also being evaluated in the phase 3 C-FORWARD study (ClinicalTrials.gov Identifier: NCT07037277), which has enrolled more than 880 treatment-naïve HCV patients in 17 countries outside North America. Topline results from this trial are expected in early 2027.

References:

Atea Pharmaceuticals meets both its primary and secondary endpoints in the phase 3 C-BEYOND North America trial evaluating bemnifosbuvir/ruzasvir for hepatitis C virus. News release. Atea Pharmaceuticals. July 28, 2026. https://www.globenewswire.com/news-release/2026/07/28/3334101/0/en/atea-pharmaceuticals-meets-both-its-primary-and-secondary-endpoints-in-the-phase-3-c-beyond-north-america-trial-evaluating-bemnifosbuvir-ruzasvir-for-hepatitis-c-virus.html.

Source: BEM/RZR Noninferior to SOF/VEL in Phase 3 C-BEYOND Hepatitis C Trial – MPR