This is a Phase 3b, randomized, open-label, parallel-group, multi-center, multi-national study of low-dose maintenance Peg interferon alpha-2b (Peg-Intron®) in subjects with human immunodeficiency virus-hepatitis C virus (HIV-HCV) co-infection. The primary objective is to compare at end of study the efficacy of Peg-Intron® monotherapy (0.5 µg/kg subcutaneously once weekly for 24-36 months) versus standard supportive care, using the time to any of the following clinical events (death, decompensation, liver transplant, hepatocellular carcinoma [HCC]) as endpoints.