Drugs in development for chronic hepatitis C: a promising future.

INTRODUCTION: The approval of the first direct-acting antiviral (DAA) drugs for treatment of HCV in 2011 has lead to improved sustained viral response rates of up to 79% in treatment-naïve or relapse genotype 1 patients. AREAS COVERED: Clinical trial data, the clinical skills required for the use of DAA drugs, the use of genetic tests and HCV RNA assays, new small molecules, resistance-associated variants, combinations of two or more DAAs, treatment of special populations, and future directions. The results of the pivotal Phase III trials with telaprevir and boceprevir, including the efficacy, safety and tolerability, drug-drug interactions and management of the most common side-effects. Resistance-associated variant data and treatment strategies implemented to minimize the development of resistance with these first-generation protease inhibitors. EXPERT OPINION: Combination therapies of protease inhibitors with nucleoside or non-nucleoside polymerase inhibitors, non-structural protein 5A (NS5A) inhibitors and cyclophylin inhibitors are currently underway in regimens that use pegylated interferon and ribavirin or are interferon-free. The explosion of new drug development will probably move the field forward and offer both improved efficacy and tolerability to patients with hepatitis C infections. The use of these drugs ushers in a new era for the treatment of HCV but must be done with care and caution.