Background/aims: To determine whether addition of amantadine to pegylated interferon/ribavirin improved response rates among chronic hepatitis C patients, non-responders to interferon/ribavirin and study the dynamic of response.
Methods: In a double blind, multicenter, randomized trial, 200 non-responder patients received pegylated interferon 1.5 microg/kg per week and ribavirin 800-1200 mg/day, plus either amantadine 200 mg/day or placebo for 48 weeks. Endpoints were virological responses, ALT normalization, and histological benefit overtime.
Results: Twenty percent of all patients achieved a sustained virological response (SVR). This rate was 8% higher in the triple therapy group (24%) compared with the double therapy group (16%) (P = 0.22). A better virological response rate at week 24 was observed in the triple regimen group (43 vs 29%; P = 0.06), which was lost at week 48 suggesting viral escape. The biochemical response rate was also significantly higher with triple therapy at week 12 (63 vs 49%; P = 0.05) and week 24 (64 vs 49%; P = 0.03). Fibrosis stabilized or improved in 77% of all patients.
Conclusions: Re-treatment of interferon/ribavirin non-responder patients should be encouraged since a substantial proportion benefits from re-treatment with pegylated interferon/ribavirin +/- amantadine. In triple therapy involving amantadine, a time wise response and an increased SVR rate in subgroups less prone to viral breakthrough suggest clues for existing controversies.