Outcome of New Direct Acting Agents For Hepatitis C

Chronic Hepatitis C virus (HCV) infection is the leading cause of advanced liver disease worldwide. The virus successfully evades host immune detection and has highly restricted requirements for growth in vitro that for many years hampered efforts to find a safe, uncomplicated, and reliable oral antiviral therapy. Ten years after discovery, pegylated interferon-alpha and ribavirin (PR) treatment for 24-48 weeks became the standard of care (1-5). PR therapy offered limited performance and availability across the diverse spectrum of HCV disease and was fraught with excessive and often limiting side effects. The first direct acting agents (DAAs) were protease inhibitors (PIs) that were introduced in 2011 and could only be used only in combination with PR because of concerns for rapid PI viral resistance. Although the first generation PIs added increased efficacy to the PR regimen, they also added new side effects and untoward drug interactions (6-8). Sofosbuvir (SOF) is a potent nucleoside inhibitor (NI) that has recently been approved for treatment of HCV. The drug has low toxicity, high resistance barrier, and minimal drug interactions with other HCV DAAs such as PIs and anti-NS5A agents. SOF is safe and effective across different viral genotypes, disease stages, and special patient groups such as those co-infected with HIV. When used in combination with ribavirin or another DAA, SOF has revolutionized the HCV treatment spectrum and set the stage for nearly universal HCV antiviral therapy. Sustained virologic response (SVR12) for SOF plus ribavirin and pegylated interferon (PR) is 90% for genotype 1 and 85-94% for genotypes 2 and 3 (9-16). SOF plus simeprevir (protease inhibitor) showed a 94% SVR12 for genotype 1 (9-16). More so than any other anti-HCV drug developed to date, SOF offers the widest applicability for all infected patients yet can be given in a personalized regimen to maximize performance