New interferons in the treatment of chronic hepatitis C.

The current standard therapy for chronic HCV infection is a combination of pegylated-interferon (PEG-IFN) and weight-based ribavirin, administered for 24-48 weeks, according to the viral genotype. Although the weekly administration of pegylated interferons provides superior antiviral efficacy over standard interferon alpha, the rate of sustained virological response rarely overpasses 50% in patients infected with HCV genotypes 1 and 4. Consequently, multiple clinical trials with congeners of interferon (consensus interferon, interferon lambda, albinterferon, and controlled-release interferons) are ongoing. Their main advantages consist in maintenance of viral suppression across a longer dosing interval, avoidance of interdose trough and reduced dosing frequencies (twice or even once per month compared to once per week for the actual PEG-IFNs). Along with these superior pharmacokinetic properties, new interferons are expected to have improved side-effect profiles and better tolerability compared with the currently available formulations, providing an option for otherwise difficult to treat, challenging populations. New interferon formulation can be incorporated into future combination with direct acting antivirals, in order to maintain viral suppression over longer periods and minimize the development of viral resistance.