Anti-viral effect of recombinant interferon alfa-2a on hepatitis C virus

Anti-viral effect of interferon alfa-2a on hepatitis C virus was evaluated by detecting hepatitis C virus ribonucleic acid (HCV RNA) in 40 patients who had received enrolled in the double-blind controlled trial of short-term (8 weeks) interferon and also in six patients who had received long-term (1 year) interferon treatment. Among the 20 patients who received short-term interferon treatment, reduction of HCV RNA was observed in 5 of 12 patients who showed the reduction of alanine aminotransferase (ALT) levels. In contrast, reduction of HCV RNA level was not observed in any of 20 patients who received the placebo. Among ten patients (six long-term and four short-term treatment) who were available for long-term follow-up, five showed the complete normalization and two showed reduction of ALT levels to less than 50 IU/1 for 1 year after the end of treatment. HCV RNA turned negative and remained negative 1 year after the end of treatment in four of these seven patients. Thus, the anti-viral effect of interferon on HCV was confirmed by detecting the HCV RNA. The clinical effect of interferon on type C hepatitis was considered to be brought about by the decrease or disappearance of the virus.