Atea's Hepatitis C Regimen Meets Noninferiority Goal Against Epclusa in Phase 3
Bemnifosbuvir/ruzasvir achieved sustained virologic response in 93.9% of patients versus 94.8% for sofosbuvir/velpatasvir in the 905-patient C-BEYOND trial, with an eight-week course for those without cirrhosis, the company said.
These results come from a Phase 3 trial, the large trial usually needed before approval.
Key points
- Atea Pharmaceuticals said on July 28 that its once-daily combination of bemnifosbuvir and ruzasvir met the primary endpoint of statistical noninferiority to sofosbuvir/velpatasvir (Epclusa) in the Phase 3 C-BEYOND trial.
- Sustained virologic response rates were 93.9% and 94.8% overall; patients without cirrhosis received eight weeks of Atea's regimen against 12 weeks of the comparator.
- A second Phase 3 trial, C-FORWARD, which has enrolled more than 880 patients outside North America, is expected to report topline results in early 2027.
Atea Pharmaceuticals said its once-daily fixed-dose combination of bemnifosbuvir and ruzasvir (BEM/RZR) was statistically noninferior to sofosbuvir/velpatasvir (SOF/VEL, sold as Epclusa) in C-BEYOND, a pivotal Phase 3 trial in chronic hepatitis C virus (HCV) infection, according to the company's July 28 announcement, distributed by GlobeNewswire and read via BioSpace. The results are company-reported topline data.
The results
In the modified intent-to-treat population of 905 patients with and without cirrhosis, BEM/RZR achieved a sustained virologic response (SVR) rate of 93.9%, compared with 94.8% for SOF/VEL, measured at week 24 and encompassing SVR 12 weeks after treatment. The 95% confidence interval for the difference was within the prespecified 5% margin, Atea said.
Among 721 patients without cirrhosis, who received eight weeks of BEM/RZR or 12 weeks of SOF/VEL, the SVR rates were 93.5% and 94.6%. In 184 patients with cirrhosis, who received 12 weeks of either regimen, both arms reached 95.4%. Virologic failure rates were low and comparable, and noninferiority was also met in secondary endpoints, including the per-protocol analysis, Clinical Trials Arena reported.
The company said BEM/RZR was generally safe and well tolerated, with no drug-related serious adverse events and no drug-related early discontinuations, and that safety was comparable between arms.
"We are pleased to announce these positive results from C-BEYOND showing our regimen of BEM/RZR achieved high cure rates across all populations and genotypes," said Jean-Pierre Sommadossi, Atea's founder and chief executive officer.
The program
C-BEYOND was an open-label trial of treatment-naive patients at about 120 sites in the US and Canada. Atea described it as the first successful head-to-head trial in a global Phase 3 program of HCV treatments. Bemnifosbuvir is a nucleotide analogue polymerase inhibitor and ruzasvir is an NS5A inhibitor; the company says the combination has a low risk of drug-drug interactions and can be taken with or without food.
The second Phase 3 trial, C-FORWARD, is fully enrolled with more than 880 patients at about 120 sites in 17 countries outside North America and includes a broader range of HCV genotypes. It is on track to report topline results in early 2027, Atea said. The company plans to present detailed results at medical conferences and submit them to peer-reviewed journals.
About 50 million people worldwide live with HCV, including up to 4 million in the US, according to the company, and about 80% to 90% of people living with HCV in the US do not have cirrhosis.
Sources
- 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 (GlobeNewswire release, read via BioSpace), Atea Pharmaceuticals via BioSpace, July 28, 2026
- Atea reports positive top line results in Phase III hepatitis C study, Clinical Trials Arena, July 29, 2026