A randomized, double-blind controlled trial of interferon alpha-2b and ribavirin vs. interferon alpha-2b and amantadine for treatment of chronic hepatitis C non-responder to interferon monotherapy

Abstract

Background/aims: Interferon-based regimens (alone or with ribavairin) are standard therapies for chronic hepatitis C. The aim of this study was to compare a 24-week regimen of interferon alpha-2b + ribavirin (IFN + RIBA) to interferon alpha-2b + amantadine (IFN + AMANT) in non-responders to previous interferon monotherapy.

Methods: In a multi-center, double-blind clinical trial, 118 patients (non-responders to previous interferon monotherapy) were equally randomized into the two arms: interferon alpha-2b (3 MU thrice weekly) and ribavirin (800 mg daily) vs. interferon alpha-2b (3 MU thrice weekly) and amantadine (200 mg daily).

Results: After 24 weeks of therapy, HCV RNA became undetectable in 34.8% (95% CI: 23.7-49.2) of IFN + RIBA and 19.6% (95% CI: 10.6-34.7) of IFN + AMANT (P = 0.10). This response was sustained in 3.9% (95% CI: 1.0-14.9) of IFN + RIBA and 0% of IFN + AMANT (P = 0.16). Ten patients from IFN + AMANT (17%) and 12 patients (20%) from IFN + RIBA were discontinued before completion of therapy. Of these, 7% in IFN + AMANT and 12% in IFN + RIBA were discontinued due to adverse effects.

Conclusions: Re-treatment of interferon non-responders with a 24-week course of IFN + AMANT was not associated with any sustained viral eradication. Although IFN + RIBA in this group was associated with a reasonable end of treatment response, relapses were common and sustained responses were low.