Background: The interest of therapy for chronic hepatitis C (CHC) in HIV-infected persons is rising since end-stage liver disease is now a leading cause of morbidity and mortality in this population. The combination of interferon (IFN) plus ribavirin (RBV) provides sustained response (SR) to nearly half of HIV-negative subjects with CHC. However, information on the efficacy and safety of this therapy in HIV+ subjects is limited to few studies, having small population sizes.

Methods: The efficacy and safety of IFN + RBV in HIV/HCV co-infected individuals was examined in a multicenter, prospective trial beginning in Spain in January 2000. Patients were randomized to receive standard doses of IFN (3 mU tiw) and RBV (800 mg BID) or an induction period of 6 weeks with IFN 6 mU daily followed by IFN 3 mU tiw + RBV until completing 6 months of therapy. Only individuals with CD4 counts >350 cells/mL and HIV-RNA <5000 copies/mL were included in the trial. All were IFN- naïve.

Results: A total of 111 subjects (82% male; mean age 36 years old; 82% on HAART) were recruited in 14 centers participating in the trial. HCV genotype distribution was 1 (47%), 3 (38%), and 4 (15%). Mean HCV-RNA was 3,280,417; and 66% harboured >2 million copies/mL. HCV-RNA clearance (Roche, limit of detection 100 copies/mL) at month 6 (end-of-treatment response) was 29%. Relapses occurred in 23% of them within the next 6 months. Therefore, sustained response was limited to 22.3%. No differences between treatment arms were noticed. Of note, 70% of responders carried HCV-3. Treatment discontinuation due to adverse effects occurred in 12%. Although many subjects who reached SR showed HCV-RNA clearance at the first month on therapy, 50% of them showed a delayed virological response. No significant drops in the CD4 count nor increases in HIV-RNA were seen, even in subjects in which RBV was taking with AZT or d4T. RBV dose reduction due to anemia only was required in 4% of subjects.

Conclusions: The combination of IFN+RBV is relatively well tolerated in HIV/HCV co-infected patients. The rate of treatment discontinuation (12%) was similar to that seen in HIV-negative individuals, and unexpected side effects were not recorded. The relatively low rate of SR in our trial might be explained by the short duration of therapy (6 months) for patients carrying HCV-1 and/or the low dose of RBV (800 mg BID) in subjects with high weight. The lack of HCV-RNA clearance one month after beginning therapy does not preclude the attainment of response much later, and therefore can not be used as treatment decision time-point.