Cure of hepatitis C virus infection without interferon alfa: Scientific basis and current clinical evidence

Cure of hepatitis C virus (HCV) infection is achievable without interferon alfa through the use of new direct-acting antiviral (DAA) drugs. In this era of interferon alfa-sparing therapy, however, interferon alfa sensitivity still matters, even as it turns out, if interferon alfa is not used. Inclusion of ribavirin in the treatment regimen remains a factor in treatment response, as does duration of treatment. HCV genotype and subtype remain relevant considerations in choosing a treatment regimen, and viral resistance may emerge when treatment fails. The potency and barrier to resistance of new DAAs and the use of appropriately designed interferon alfa-sparing combinations can overcome obstacles to cure posed by HCV resistance, interferon alfa resistance, and differences in response based on HCV genotype and subtype. Studies demonstrating the use of new DAAs to overcome these obstacles are discussed.