PEG-rIL-29 (also known as PEG-interferon lambda) is a unique Type III interferon molecule that has demonstrated antiviral activity when administered weekly for 4 weeks to treatment-relapsed and treatment-naive subjects with genotype 1 hepatitis C virus (HCV) infection. Because PEG-rIL-29 binds to a unique receptor with a more limited distribution than the receptor for interferon (IFN)-α, it may have the potential to treat HCV without some of the treatment-limiting side effects associated with IFN-α-based therapies. The purpose of this Phase 2a/b randomized, controlled, multicenter study is to compare the safety and efficacy of PEG-rIL-29 and peginterferon alfa-2a, both administered subcutaneously weekly for up to 48 weeks in combination with daily oral ribavirin, in treatment-naive subjects with chronic genotype 1, 2, 3, or 4 HCV infection. The initial part of the study (Phase 2a) will be conducted as an open-label study; the second part of the study (Phase 2b) will be conducted as a blinded study. The above information provided in this listing is specific to the Phase 2b portion of the study. In addition, two small open-label substudies will be conducted to evaluate the efficacy of 24-week treatment with PEG-rIL-29 and ribavirin in subjects with HCV genotype 1 who have a particular genetic polymorphism associated with favorable response (n=60) and to evaluate the efficacy of 16-week treatment with PEG-rIL-29 and ribavirin in subjects with HCV genotype 2 or 3 (n=30).
