FDA approved Zepatier (elbasvir and grazoprevir) for the treatment of adult patients with chronic hepatitis C virus genotype 1 or 4 infection, with or without ribavirin, following priority review.
Zepatier is a once-daily combination tablet containing the NS5A inhibitor elbasvir (50 mg) and the NS3/4A protease inhibitor grazoprevir (100 mg). The FDA previously granted two Breakthrough Therapy designations to Zepatier, for the treatment of chronic HCV GT1 infection in patients with end stage renal disease on hemodialysis, and for the treatment of patients with chronic HCV GT4 infection.
Across multiple clinical studies, Zepatier achieved high rates of sustained virologic response ranging from 94 to 97 percent in GT1-infected patients, and 97 to 100 percent in GT4-infected patients, according to Merck, the therapy’s sponsor. Sustained virologic response is defined as HCV RNA levels measuring less than the lower limit of quantification at 12 weeks after the cessation of treatment.
Zepatier was approved with a treatment duration of 12 or 16 weeks, depending on HCV genotype, prior treatment history and, for patients with GT1a infection, the presence of certain baseline NS5A polymorphisms. A 12-week, once-daily regimen is recommended for the vast majority of patients for whom Zepatier is indicated.
