Background: Vaniprevir is a potent macrocyclic hepatitis C virus (HCV) nonstructural protein 3/4A protease inhibitor. This phase III study evaluated the safety and efficacy of vaniprevir in combination with peginterferon alfa-2b and ribavirin (PR) for 24 weeks compared with PR alone for 48 weeks in treatment-naive Japanese patients with HCV genotype 1 infection.
Methods: Treatment-naive Japanese patients with HCV genotype 1 infection were randomly assigned to receive vaniprevir (300 mg twice daily) plus PR for 12 weeks then PR alone for 12 weeks, vaniprevir (300 mg twice daily) plus PR for 24 weeks, or PR alone for 48 weeks.