Despite the availability of direct-acting antiviral oral combination treatment regimens and eradication efforts by the World Health Organization and others, HCV continues to be a serious viral disease. An estimated 47 million people globally live with chronic HCV infection, with approximately 1 million new infections occurring each year. In 2024, HCV led to an estimated 240,000 deaths. These deaths are primarily attributable to cirrhosis and hepatocellular cancer, each of which are serious long-term consequences resulting from prolonged exposure, generally up to 20 years of HCV infection.
In the US, it is estimated that there up to 4 million people living with untreated HCV infection. Further it is reported that on an annual basis in the US, there are approximately 160,000 newly reported chronic HCV infections. This incidence of newly reported infections substantially outpaces rates of treatment, which is estimated to be approximately 85,000 annually.
In the US and elsewhere, HCV is increasingly affecting younger people, with high case rates among those between 20 to 49 years of age. Since recently infected and younger patient populations are less likely to have developed cirrhosis given the relatively shorter cumulative exposure to the virus, there has been a trend in the US of a decreasing incidence of cirrhosis among individuals with HCV infection. It is estimated that 10-20% of the HCV-infected population in the US has cirrhosis.
In 2025, global net sales of HCV therapeutics known in the US as Mavyret® and Epclusa®, together with the authorized generic copy of Epclusa®, approximated $2.5 billion with the US contributing approximately 50% of these sales. Given the large number of patients currently infected with HCV and high rates of annual incidence, it is expected that a substantial global market will exist for the foreseeable future.
The regimen of bemnifosbuvir /ruzasvir has demonstrated a potential best-in-class profile that combines the most compelling attributes of current HCV drug treatments. Atea’s combination regimen is protease inhibitor-free with a potential profile of short treatment duration, low risk of drug-drug interactions and convenience with no food effect.
The global Phase 3 program is evaluating the fixed-dose combination (FDC) of bemnifosbuvir (BEM), a nucleotide analog polymerase inhibitor, and ruzasvir (RZR), an NS5A inhibitor, for the treatment of chronic HCV in patients with and without compensated cirrhosis. The program consists of two open-label controlled trials, which have collectively enrolled over 1,760 treatment-naïve patients: C-BEYOND (NCT06868264) in North America and C-FORWARD (NCT07037277) outside North America. The trials compare the FDC regimen of BEM/RZR, to the FDC regimen of sofosbuvir and velpatasvir (SOF/VEL; EpclusaÆ). 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 SOF/ VEL is administered orally once daily for 12 weeks to all patients, with or without compensated cirrhosis.
The primary endpoint for each trial is HCV RNA below the 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. SVR12 is the accepted definition of cure for HCV. 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. In C-BEYOND, the primary endpoint was assessed in the modified intent to treat (mITT) population, which is comprised of all patients who received at least one dose of the regimen and includes patients who discontinued early, were not compliant or were lost to follow-up.
In July 2026, Atea announced positive topline results from C-BEYOND, its Phase 3 trial conducted in North America. The trial achieved its primary and secondary endpoints.
Patients in C-BEYOND included those who are taking concomitant medications (~89%), reported injection drug use as the HCV route of transmission (≥ 55%), diagnosed with a comorbid psychiatric disorder (~66%), prematurely discontinued treatment, lost to follow-up or did not adhere to protocol treatment (>10%).
These C-BEYOND patients are reflective of the current real-world population living with HCV in the US and Canada and underscore the importance of a simplified treatment option with
C-BEYOND topline Phase 3 results included:
In the modified intent to treat (mITT) primary endpoint analysis (n=905, cirrhotic and non-cirrhotic), BEM/RZR achieved a 93.9% SVR rate vs. 94.8% for SOF/VEL (Epclusa®) at Week 24, encompassing SVR at 12 weeks (accepted definition of cure for HCV) in both arms. The trial achieved its primary endpoint of statistical non-inferiority, with a 95% confidence interval for difference in SVR rates within the prespecified 5% margin. Statistical non-inferiority was also met in secondary endpoints, including the per-protocol analysis.
The mITT analysis in patients without cirrhosis (n=721) showed BEM/RZR (8 weeks of treatment) achieved a 93.5% SVR rate vs. 94.6% for SOF/VEL (12 weeks of treatment). In patients with cirrhosis (12 weeks treatment in both arms) (n=184), BEM/RZR achieved a 95.4% SVR rate vs. 95.4% for SOF/VEL.
Rates of virologic failure across all populations were low and comparable between treatment arms.
Atea is advancing C-FORWARD, its second Phase 3 trial, being conducted outside North America. Patient enrollment for C-FORWARD was completed in June 2026 with more than 880 patients across 17 countries. Topline results are expected in early Q1 2027 and will provide additional efficacy data across a broader range of HCV genotypes more commonly found outside of the US and Canada.
Atea is late-stage clinical biopharmaceutical company engaged in the discovery and development of oral antiviral therapeutics for serious viral diseases.
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