Recent advance in antiviral drugs for hepatitis C.

Hepatitis C virus (HCV) infection is the leading cause of chronic liver diseases worldwide. There is no vaccine to prevent HCV infection. Current standard of care (SOC) for hepatitis C is pegylated interferon-α (pegIFN-α) in combination with ribavirin (RBV). However, the efficacy of pegIFN-α and RBV combination therapy is less than 50% for genotype 1 HCV, which is the dominant virus in human. Additionally, IFN and RBV are highly toxic, causing severe side effects. Therefore, it is urgent to develop safer and more efficacious anti-HCV drugs. Over the last decade, a number of HCV-specific inhibitors have been discovered with many of them reached to late stages of clinical trials. Recently, 2 HCV NS3 protease inhibitors, telaprevir and boceprevir, have been approved by the Unite States Food and Drug Administration (FDA). This opens up a new era for anti-HCV therapy. Several new classes of antiviral drugs targeting HCV NS3 protease, NS5A and NS5B RNA-dependence RNA polymerase (RdRp) are currently at various stages of preclinical and clinical studies. Upon approval of more NS3 protease, NS5A and NS5B polymerase inhibitors, future clinical studies will lead to optimal combination therapies which will have desirable parameters such as IFN-free, higher efficacy, safe, one daily dose and short duration.