Recent Advancement of Direct-acting Antiviral Agents (DAAs) in Hepatitis C Therapy.

Hepatitis C virus (HCV) infection is a major health problem worldwide. Approximately, 170-200 million individuals are chronically infected worldwide and a quarter of these patients are at increased risk of developing liver cirrhosis, hepatocellular carcinoma and even liver failure. A complete eradication of the virus is one of the most important treatment goals for antiviral research. In 2011, the first-generation protease inhibitors boceprevir (BOC) telaprevir (TVR) were approved by FDA as the direct-acting antiviral agents. A number of promising new direct-acting antiviral agents (DAAs) have been developed in the past few years. Due to their increased efficacy, safety, and tolerability, interferon-free oral therapies with DAAs are in use for patients with chronic HCV and cirrhosis patients. In this review, we will discuss the results of clinical trials of several DAAs and the approved combinations, including NS3/4A protease inhibitors, NS5A inhibitors, and NS5B inhibitors. A number of drugs, including Sovaldi®, Harvoni® Viekira Pak®, Epclusa®, Zepatier® have been approved by FDA in the past two-three years. The latest advancement of DAA therapy and related side effects due to the therapy are also discussed.