Long-term efficacy of recombinant interferon alpha 2a in the treatment of chronic hepatitis C: A randomized prospective study comparing two dose schedules in Chinese patients

BACKGROUND/AIMS: This study is the first randomized prospective clinical tr ial of interferon in hepatitis to be conducted according to the guidelines of Good Clinical Practice (GCP) in China. The object of this study is to co mpare the long-term efficacy of a dose of 3MU of recombinant IFN alpha 2a ( rIFN-alpha 2a) three times a week (t.i.w.) for 6 months with a starting dos e of 6MU for 3 months and subsequent reduction to 3 MU t.i.w for a further 3 months. METHODOLOGY: Sixty-eight serological and histologically proven chronic hepa titis C patients with elevated serum ALT were randomized into two groups. A total of 63 patients were studied with full course of treatment. Five pati ents were withdrawn from the trial, 2 due to personal reasons and 3 due to adverse drug reactions during treatment. Thirty patients received 6MU IFN-a lpha 2a t.i.w. for 3 months followed by 3MU t.i.w. for another 3 months (gr oup A). Thirty-three patients received 3MU IFN-alpha 2a t.i.w. for 6 months (group B). RESULTS: The sex, age, baseline serum bilirubin, ALT and AST levels were ma tched in both groups. At the end of 6 months the complete and partial respo nse rates in group A were 60.0% and 16.7%, respectively, and the clearance of serum HCV-RNA was 53.3%. In group B, the complete and partial response r ates were 72.7% and 3.0%, respectively, and the clearance of HCV-RNA was 61 .3%. These patients were followed up for 6, 12, and 18 months after stoppin g treatment. In group A, the rates of complete normalization of ALT and cle arance of serum HCV-RNA at 24 months were 50.0% and 60.0%, respectively. In group B, the rates of normalization of ALT and clearance of HCV-RNA at 24 months were 54.4% and 41.9%, respectively. The efficacy between the two gro ups showed no statistically significant difference; the response rates of t reatment were similar to the patients with HCV genotype 1b and 2a. Six pati ents (10.8% of the study population) developed neutralization antibodies to IFN-alpha 2a during treatment, 4 of them responded to the treatment. Adver se drug reactions (ADR) were common, but most of them were tolerable and th e incidence of ADR was similar in both groups. CONCLUSIONS: IFN-alpha 2a is effective in the treatment of Chinese patients with chronic hepatitis C. The sustained response rates and ADR among two d ose schedule groups are similar.