New hepatitis C virus (HCV) drugs and the hope for a cure: concepts in anti-HCV drug development.

The development of new models and tools has led to the discovery and clinical development of a large number of new anti-hepatitis C virus (HCV) drugs, including direct-acting antivirals and host-targeted agents. Surprisingly, curing HCV infection appears to be easy with these new drugs, provided that a potent drug combination with a high barrier to resistance is used. HCV infection cure rates can be optimized by combining drugs with synergistic antiviral effects, tailoring treatment duration to the patients' needs, and/or using ribavirin. Two HCV drugs have been approved in 2011--telaprevir and boceprevir, both first-wave, first-generation NS3-4A protease inhibitors, two others in 2013/2014--simeprevir, a second-wave, first-generation NS3-4A protease inhibitor, and sofosbuvir, a nucleotide analogue inhibitor of the viral polymerase. Numerous other drugs have reached phase II or III clinical development. From 2015 and onwards, interferon-containing regimens will disappear, replaced by interferon-free regimens yielding infection cure rates over 90%. These therapies will raise new issues, including the need for broad-scale screening and access to care.