Abstract
Background & Aims:
Bemnifosbuvir and ruzasvir are potent pan-genotypic inhibitors of the hepatitis C virus (HCV) NS5B polymerase and NS5A protein, respectively. This single-arm, Phase 2 study evaluated the efficacy and safety of bemnifosbuvir and ruzasvir in treatment-naïve patients with chronic HCV infection of any genotype, with or without compensated cirrhosis.
Approach & Results:
Patients received bemnifosbuvir 550 mg and ruzasvir 180 mg once daily for 8 weeks (intention-to-treat [ITT] population). The primary efficacy endpoint was the proportion of patients achieving sustained virologic response at 12 weeks post treatment (SVR12) in the Pharmacokinetic and Pill Compliant Per-Protocol (PK/PC-PP) population. Secondary efficacy endpoints included SVR12 in the Efficacy Evaluable Per-Protocol (EE-PP; those with outcomes regardless of study drug adherence) and safety (all dosed) populations, virologic failure, and SVR24. Of the 275 patients enrolled and who received treatment with bemnifosbuvir and ruzasvir, 13% had compensated cirrhosis and 27% had NS5A resistance-associated substitutions (RASs) at baseline. SVR12 was 90% (248/275; 95% CI: 86–93%) in the ITT population, 98% (210/215; 95% CI: 95–99%) in the PK/PC-PP population, and 95% (245/259; 95% CI: 91–97%) in the EE-PP population. Five patients in the PK/PC-PP population experienced virologic failure (post-treatment relapse). No drug-related serious adverse events or premature treatment discontinuations due to drug-related adverse events were reported.
Conclusions:
An 8-week treatment with bemnifosbuvir and ruzasvir resulted in high rates of SVR12 across genotypes, regardless of the presence or absence of baseline RASs, and was well tolerated among treatment-naïve HCV patients.