Persistent hepatitis C virus (HCV) infection is a leading cause of chronic 
hepatitis, cirrhosis, and hepatocellular carcinoma and the major indication for 
liver transplantation in adults. Current standard of care treatment (SOC) with 
pegylated-interferon-α 2 and ribavirin (RBV) has a limited efficacy and is 
associated with significant side effects frequently associated with poor 
compliance or treatment discontinuation, requiring specialized and frequent 
monitoring. To overcome the limited efficacy of SOC, more than 50 direct-acting 
antiviral agents (DAA) designed to target viral-encoded proteins essential in 
the HCV life cycle are currently under development. The rapid selection of 
resistant mutants associated with the quasispecies nature of HCV with high 
mutation and replication rates is one of the main challenges for the new HCV 
therapies. Predictive host and viral factors together with combination of DAAs 
with or without IFN and/or RBV need to be accurately evaluated to design the 
most effective individualized treatment strategy within the shortest time 
interval and with minimum side effects.