Hepatitis C virus (HCV) represents a significant health burden worldwide, with an estimated 185 million people chronically infected. A leading cause of liver transplantation, HCV infection can result in severe liver disease including cirrhosis and hepatocellular carcinoma. Cure of HCV infection results in substantial decreases in such liver-related morbidity and mortality. Prior therapies for HCV offered only 40% cure for the most difficult-to-treat genotype-1 infection, required 48 weeks of therapy with an injectable interferon, and included significant adverse events.