Interferons exhibit antiviral and immunomodulatory properties. Antiviral effects appear mainly mediated via 2'5' oligoadenylate synthetase and protein kinase proteins which inhibit viral components synthesis. Interferons also influence the immune system through various mechanism among whom an increased expression of HLA class I antigens on hepatocyte plasma membrane and the promotion of natural killer cell activity leading to the clearance of infected hepatocytes. We report the results of various alpha interferon therapeutic regimens in 60 patients with chronic hepatitis C. In our series, 20 patients (33%) achieved a complete response but 78% of them relapsed after therapy withdrawal. Predictors of good response include young age, low serum ALT levels and mild liver injury. On the contrary, cirrhosis is associated with a poorer response.