Emerging therapies for chronic hepatitis C virus.

Current hepatitis C virus (HCV) therapies are associated with significant adverse events and less-than-ideal sustained virologic response (SVR) rates in genotype 1 patients. The current standard of care, a combination of pegylated interferon and ribavirin, will likely remain a key component of the treatment regimen for years to come. Multiple new drugs are currently in development and are expected to be approved for use in the United States and/or European Union by 2011 at the earliest. Future therapies will include novel interferons, ribavirin analogues, NS3 HCV protease inhibitors, NS5b HCV polymerase inhibitors, cyclophilin inhibitors, and other novel agents. There is hope that multiple new drugs will be approved over the following 4-10 years to provide alternative treatment choices, improved SVR rates, and reductions in adverse events. However, a number of barriers must be overcome prior to the acceptance of these drugs, involving, but not limited to, their toxicity, viral resistance, optimal dose, duration, and their efficacy and safety in patients with unmet needs.