Emerging therapeutic options in hepatitis C virus infection.

The current standard of care for patients with chronic hepatitis C virus (HCV) infection is pegylated interferon alfa in combination with ribavirin. Treatment duration and efficacy depend heavily on HCV genotype. A sustained virologic response (SVR) is achieved only in approximately 40% of patients. Side effects of the current standard of care often make adherence to therapy difficult, further reducing the chance for an SVR. Numerous patient-related and virus-related factors can determine response to treatment. Nonresponders are a large proportion of the current HCV-infected population, and the number of patients with HCV infection is growing, necessitating newer therapies with higher efficacy and potentially fewer side effects. A new era of direct acting antiviral (DAA) compounds has emerged. The first 2 protease inhibitors for HCV infection, telaprevir and boceprevir, are coming to market in 2011. Other protease compounds in development include TMC-435, vaniprevir, BI-201335, BMS-650032, and danoprevir. The numerous other therapies that have potential in the treatment of HCV infection include nucleoside inhibitors, non-nucleoside inhibitors, NS5A inhibitors, DAA combinations, therapeutic vaccines, human monoclonal antibodies, immune modifiers, and interferon lambda.