Peginterferon alfa-2a/ribavirin in hepatitis C virus patients nontolerant or nonresponsive to peginterferon alfa-2b/ribavirin

Background: Peginterferon alfa-2a/ribavirin treatment resulted in fewer incidences of depression and flu-like symptoms than that of standard interferon/ribavirin, whereas peginterferon alfa-2b/ribavirin and standard interferon/ribavirin treatment resulted in similar incidences of these adverse events (AEs). Aim: To assess the efficacy and safety of peginterferon alfa-2a/ribavirin in genotype 1-infected patients treated for up to 12 weeks with peginterferon alfa-2b/ribavirin but not achieving early virologic response (EVR) (non-EVR) or nontolerant (NT) because of depression, fatigue, flu-like symptoms, or injection-site reactions. Methods: Nontolerants were treated for an additional 36 weeks and non-EVRs for an additional 60 weeks with peginterferon alfa-2a (180 μg/week)/ribavirin (1000/1200 mg/day). Patients with detectable HCV RNA after 12 weeks were discontinued. Results: Of 25 NTs, 23 (92%) were HCV-RNA negative after 12 weeks on peginterferon alfa-2a/ribavirin and 14 (56%) achieved sustained virologic response. Of 32 non-EVRs to peginterferon alfa-2b/ribavirin, four (13%) achieved EVR with peginterferon alfa-2a/ribavirin and one (3%) achieved sustained virologic response. Four non-EVRs and 0 NTs were withdrawn for AEs; 26 (81%) and 24 (96%), respectively, completed peginterferon alfa-2a/ribavirin treatment or were withdrawn for insufficient response at week 12. In NTs, depression, fatigue, flu-like symptoms, and injection-site reactions declined during treatment. Conclusion: Most patients who did not tolerate peginterferon alfa-2b/ribavirin because of AEs, and who completed the full 36-week course of peginterferon alfa-2a/ribavirin treatment, achieved sustained virologic response.