Direct Acting Anti-hepatitis C Virus Drugs: Clinical Pharmacology and Future Direction.

Chronic hepatitis C virus (HCV) infection is a leading cause of chronic liver disease. The introduction of direct acting antiviral agents (DAAs) for its treatment represents a major advance in terms of sustained virologic response (SVR) rates and adverse effect profiles. Mechanistically, DAAs inhibit specific HCV non-structural proteins (NS) that are vital for its replication. Boceprevir, telaprevir, simeprevir, asunaprevir, grazoprevir and paritaprevir are NS3/4A inhibitors. Ombitasvir, ledipasvir, daclatasvir, elbasvir and velpatasvir are NS5A inhibitors. Sofosbuvir and dasabuvir are NS5B inhibitors. Currently, a combination of two or more DAAs is the corner stone for the treatment of HCV infection. However, the success of DAA therapy is facing several challenges, including the potential of drug-drug interactions and resistant variance. Moreover, the shortage of relevant clinical pharmacological data and drug interaction regarding DAA is a clinical concern. The present review discusses the clinical pharmacology of DAAs with special emphasis on drug-drug interaction.