Summary. Although health-related quality of life (HRQOL) is diminished in HCV/HIV, the relationship between virologic response and maintenance therapy with HRQOL in this population is unknown. ACTG 5178 was a phase 2, randomized trial, with three steps – Step 1: all subjects received pegylated interferon (PEG-IFN)/ribavirin (P/R) for 12 weeks. Step 2: subjects who failed to achieve early viral response (EVR) were randomized to PEG-IFN or observational control for an additional 72 weeks. Step 3: subjects with EVR from step 1 continued on P/R for a total of 72 weeks with 24 weeks follow-up off-therapy. HRQOL, symptom distress and depression levels were measured at multiple time points. In step 1 (n = 329), there was a significant decline in HRQOL in all dimensions. In step 3 (n = 169), the overall HRQOL and three of its eight dimensions (general health, role function and pain score) were increased, and achievement of sustained virologic response was associated with increased general health and cognitive function. In step 2 (n = 85), there was no significant change in HRQOL and no significant difference between groups (PEG-IFN vs observational control). There was a significant decline in HRQOL during the initial 12 weeks of therapy. Thereafter, the HRQOL profile differed for subjects with EVR vs without EVR. Maintenance therapy with PEG-IFN had no impact on the HRQOL.