Atea Pharmaceuticals announced today that its investigational, combination hepatitis C virus (HCV) therapy of bemnifosbuvir and ruzasvir met its primary endpoint for its phase 2 clinical trial. The therapy achieved a 98% sustained virologic response at 12 weeks post-treatment (SVR12) after 8 weeks of treatment.1
“These high SVR12 results with only 8 weeks of treatment with our regimen are extremely exciting and very significant given the unmet needs for today’s HCV patients. We are eager to discuss our program with regulators, including the US Food and Drug Administration, to promptly advance to phase 3 development early next year,” Atea CEO Jean-Pierre Sommadossi, PhD, said in a statement.1
In the phase 2 trial, 99% (178/179) of treatment adherent patients who were non-cirrhotic and infected with genotypes 1-4 achieved SVR12, showed robust pan-genotypic potency and supported the potential of a 8-week treatment in a phase 3 study. Treatment adherent patients with cirrhosis achieved a 88% (30/34) SVR12 rate. Viral kinetics were slower in these participants. Nonethless, all patients achieved 100% end of treatment response. To maximize efficacy, treatment duration in patients with cirrhosis will be 12 weeks in the phase 3 study.1
What You Need to Know
The investigational combination therapy for hepatitis C (HCV), comprising bemnifosbuvir and ruzasvir, achieved a 98% sustained virologic response (SVR12) at 12 weeks post-treatment after just 8 weeks of therapy, demonstrating robust pan-genotypic potency and efficacy across genotypes 1-4 in non-cirrhotic patients.
Bemnifosbuvir and ruzasvir exhibit favorable safety profiles, strong antiviral activity, and minimal risk of drug-drug interactions.
Atea Pharmaceuticals plans to move into phase 3 development early in 2025.
The Combination Therapy
According to the company, bemnifosbuvir has been shown in in vitro studies to be approximately 10-fold more active than sofosbuvir (SOF), against a panel of laboratory strains and clinical isolates of HCV GT 1–5. In vitro studies have also demonstrated bemnifosbuvir remained fully active against SOF resistance-associated substitutions (S282T), with up to 58-fold more potency than SOF.2
The pharmacokinetic (PK) profile of bemnifosbuvir supports once-daily dosing for the treatment of HCV. Bemnifosbuvir has been shown to have a low risk for drug-drug interactions. Bemnifosbuvir has been administered to over 2,200 subjects and has been well-tolerated at doses up to 550 mg for durations up to 12 weeks in healthy subjects and patients.2
The other half of the combination, ruzasvir, has demonstrated highly potent and pan-genotypic antiviral activity in preclinical (picomolar range) and clinical studies. Ruzasvir has been administered to over 1,500 HCV-infected patients at daily doses of up to 180 mg for 12 weeks and has demonstrated a favorable safety profile. The PK profile of ruzasvir supports once-daily dosing.2
Next Steps
The company is working towards initiating a phase 3 study in early 2025. It is expected that the phase 3 program will use a fixed dose combination (FDC) tablet reducing the daily pill count from 4 to 2 tablets, enhancing patient convenience, with no food effect.
“Our regimen has a potential best-in-class profile that includes the key features for successfully treating today’s HCV patients including convenience, low risk for drug-drug interactions and short treatment duration,” Sommadossi said. “We believe that this regimen has the potential to play a major role in the eradication of HCV in the US.”
Reference
1. Atea Pharmaceuticals Announces Positive Results from Phase 2 Study of Bemnifosbuvir and Ruzasvir Regimen for Treatment of Hepatitis C Virus (HCV). Atea press release. December 4, 2024. Accessed December 4, 2024.
https://ir.ateapharma.com/news-releases/news-release-details/atea-pharmaceuticals-announces-positive-results-phase-2-study
2. Atea Pharmaceuticals Presents Multiple New Datasets Supporting the Combination of Bemnifosbuvir and Ruzasvir for the Treatment of Hepatitis C Virus at AASLD’s The Liver Meeting 2024. Atea Pharmaceuticals press release. November 15, 2024. Accessed November 19, 2024.
https://ir.ateapharma.com/news-releases/news-release-details/atea-pharmaceuticals-presents-multiple-new-datasets-supporting
