Efficacy of long-term interferon therapy in chronic hepatitis B patients with HBV genotype C.

Infection with Hepatitis B virus (HBV) genotype C predominates in Japan. We analyzed the efficacy of interferon (IFN) alpha or beta in the treatment of chronic hepatitis B patients with HBV genotype C and the clinical predictors for therapeutic response. Forty-three genotype C-infected, chronic hepatitis B e antigen (HBeAg)-positive patients (32 men and 11 women with a mean age of 35.6+/-10.1 years) who had been treated with IFN therapy were retrospectively studied. The patients were classified into two treatment groups. Short-term therapy group was administered a 5-6 MU dose three times weekly for 4 weeks, and the long-term therapy group for 24 weeks. At the end of the follow-up period, 4 (15%) of 27 short-term therapy group patients and 6 (38%) of 16 long-term therapy group patients had normalized serum ALT levels and seroconversion of HBeAg to anti-HBe (p=0.137). Multivariate analysis for parameters most important for the efficacy of IFN therapy was performed using Cox proportional hazard models in order to investigate the association between baseline characteristics of patients and the response to IFN treatment. As a result, the p-values of IFN treatment group and sex were <0.05, and both factors can be recognized as independent significant factors (relative risk, 2.93 and 2.53; p=0.027 and 0.040, respectively). Furthermore, the cumulative rates of seroconversion of HBeAg to anti-HBe analyzed by the Kaplan-Meier method was significantly higher in the female group (p=0.015) and in the long-term IFN therapy group (p=0.0046). In summary, long-term IFN therapy may be more effective than short-term IFN therapy for patients with chronic HBV genotype C infection.