Study of PEG-rIL-29 (or PEG-IFN Lambda) in Subjects With Chronic Hepatitis C Virus Infection

This is a 3-part study of PEG-rIL-29 in subjects with chronic genotype 1 hepatitis C virus infection who have either received no prior treatment with a PEGylated IFN-α (or other form of IFN-α) or who have relapsed following prior treatment with a PEGylated IFN-α (or other form of IFN-α) and ribavirin. Part 1 of the study will evaluate the safety and tolerability of escalating doses of PEG-rIL-29 when given as a single agent either every other week or weekly over a 4-week period to treatment-relapsed subjects. Part 2 of the study will evaluate dose levels and/or schedules of PEG-rIL-29 in combination with daily oral ribavirin administered over a 4-week period to treatment-relapsed subjects. Part 3 of the study will evaluate dose levels and/or schedules of PEG-rIL-29 in combination with daily oral ribavirin administered over a 4-week period to subjects who have received no prior treatment.