Peg-Interferon Alpha-2a versus Peg-Interferon Alpha-2b in Nonresponders with HCV Active Chronic Hepatitis: A Pilot Study

Background: The efficacy and tolerability of Peg-Interferon alpha-2a (Peg-IFN alpha-2a) versus Peg-Interferon alpha-2b (Peg-IFN alpha-2b) were compared in a patient cohort with hepatitis C virus (HCV)-related active chronic hepatitis, unresponsive to previous antiviral treatment with standard IFN (6 MU three times/week) plus ribavirin (10.6 mg/kg/day) for a period of at least 3 months. Patients and methods: A total of 143 patients were enrolled and randomized into two treatment groups (A-B). Group A (71 patients) received one vial of Peg-IFN alpha-2a weekly (180 mu g) subcutaneously whereas Group B (72 patients) received 1.5 mu g/kg of Peg-IFN alpha-2b weekly subcutaneously. Interferon was combined with ribavirin (15 mg/kg/day) in both groups and all patients who demonstrated nondetectable HCV-RNA or a >= 2(log) reduction in viral load at week 12, were treated for 48 weeks, with a 24-week follow up. Results: Group A (10/71) and Group B (8/72) patients discontinued treatment due to severe side effects. At the end of therapy, HCV-RNA was undetectable in 17/71 (23.9%) Group A and in 19/72 (26.4%) of Group B patients. When terminating follow up, a sustained virological response was observed in 14/71 in Group A (19.7%) and 13/72 in Group B (18.0%). Conclusions: Within the limits of the relatively small sample size, Peg-IFN alpha-2a and Peg-IFN alpha-2b demonstrated nonstatistically significant differences in effectiveness in patients nonresponsive to previous antiviral treatment.