The Polymerase Chain Reaction: Essential for the Development of Curative Therapy for Hepatitis C.

Abstract

Hepatitis C virus (HCV), a single-stranded RNA virus, infects nearly 180 million people worldwide. The treatment of this chronic infection is currently undergoing one of the greatest ‘sea changes’ experienced in modern medicine in that a disease to which millions of deaths have been attributed globally could be virtually eliminated in our lifetime. This shift is due to the replacement of difficult-to-tolerate, injectable interferon-based therapies, given for up to a year with moderate chances of success, by all oral “direct acting antivirals” (DAA), specifically designed to act against HCV proteins including nonstructural (NS)3/4A (a serine protease), NS5A (a viral protein essential for viral assembly and RNA replication) and NS5B (a RNA dependent RNA polymerase). These new medications have markedly increased cure rates (over 90% in most cases), with far fewer adverse effects and shortened courses of therapy[1–3]. At the heart of this change to a more focused model of treatment has been the use of polymerase chain reaction (PCR)-based technologies (among others) in the understanding of key components of the HCV life-cycle and the design of DAAs. In conjunction with this, there has been on ongoing roll-out and expansion of PCR-based assays in regular clinical use for HCV.