Histological response to pegIFNα-2a (40KD) plus ribavirin in HIV-hepatitis C virus co-infection

OBJECTIVE: Paired liver biopsies from patients enrolled in the multinational AIDS PEGASYS Ribavirin International Co-infection Trial were analysed to investigate a possible correlation between virological and histological responses. DESIGN AND METHODS: A total of 860 HIV-hepatitis C virus (HCV)-co-infected patients were randomly assigned to receive pegIFNα-2a (40KD) 180 μg/week plus 800 mg daily ribavirin, pegIFNα-2a (40KD) plus placebo or conventional IFNα-2a 3 MIU three times a week plus ribavirin for 48 weeks. Paired biopsies were obtained from 401 patients and scored locally using the Ishak-modified histological activity index (HAI). The second biopsy was obtained, on average, 26 weeks or more after the end of treatment. Histological response was defined as a 2-point or greater reduction in the HAI score. RESULTS: The histological response rate was significantly higher in patients receiving pegIFNα-2a (40KD) plus ribavirin (57%) than in patients receiving pegIFNα-2a (40KD) plus placebo (39%; P < 0.017) or IFNα-2a plus ribavirin (41%; P = 0.04). Histological response was correlated with virological response, with the histological response rate ranging from 62 to 74% in patients who achieved a sustained virological response (SVR). Histological response was also seen in 32-43% of patients not achieving an SVR. A higher total HAI score was the only prognostic factor for achieving histological response. CONCLUSION: The histological response rate was significantly higher in HIV-HCV-co-infected patients who received pegIFNα-2a (40KD) plus ribavirin than in those receiving pegIFNα-2a (40KD) plus placebo or IFNα-2a plus ribavirin. Histological response was correlated with virological response, although a substantial proportion of patients who did not achieve an SVR experienced histological improvement.