Comparative efficacy and overall safety of different doses of consensus interferon for treatment of chronic HCV infection: a systematic review and meta-analysis

Background About one-half of patients with hepatitis C genotype 1 and one-third with genotype 2/3 have treatment failure with peginterferon alpha and ribavirin. Consensus interferon (CIFN) is an option for retreatment of these patients. Objective To summarize comparative safety and efficacy of different regimens of CIFN for the treatment of patients with chronic hepatitis C infection. Data source Medline, Scopus, ISI, and Cochran Central Register of Clinical Trials were used. Study eligibility criteria Randomized clinical trials (RCTs) were eligible for inclusion in the study. Participants HIV and HBV seronegative patients with positive HCV-RNA during the 6 months before the start of the study were eligible for inclusion. Interventions Different regimens of CIFN were studied. Study appraisal and synthesis methods Studies were appraised based on methods of random sequence generation, allocation concealment, and blinding. The random effects model of DerSimonian and Laird was employed to run the meta-analysis. The end-point was sustained virological response (SVR). Results Data of 10 RCTs including 1,600 subjects were extracted. High daily induction dose regimen of CIFN did not yield a higher rate of SVR than low daily induction dose treatment regimen, RR = 0.83 (95% CI 0.58-1.17). A dose of 9 μg thrice weekly (tiw) was associated with a significantly higher rate of SVR compared with 3 μg [RR = 3.14 (95% CI 1.68-5.58)]‹. Withdrawal rate was similar [RR = 1.28 (95% CI 0.65-2.50)] but dose modification was higher in 9 μg [RR = 3.22 (95% CI 1.08-9.60)]. A dose of 18/15 μg tiw was not more effective than 9 μg over a similar treatment duration [RR = 1.02 (95% CI 0. 87-1.19)]. Limitations Limitations include inadequate reporting of methodological information and side effects, lack of publication bias assessment due to the small number of studies in each analysis. Conclusions High dose daily induction therapy with CIFN is not superior to low dose therapy in terms of SVR. It seems that 9 μg tiw is the optimal treatment dose of CIFN for treatment of HCV infection. Optimal duration and safety profile of CIFN therapy have yet been elucidated.