Six RCTs (n=1,756) were included in the review. Sample sizes ranged from 95 to 860 participants. The authors stated that the quality of included studies was high. Publication bias was detected for studies that evaluated the treatment of HCV genotypes 2 or 3, but not for genotypes 1 and 4.
Participants treated with peginterferon plus ribavirin had greater sustained response rates than participants treated with interferon plus ribavirin (RR 3.23, 95% CI 2.27 to 4.6; five trials). There was no statistical heterogeneity between studies.
Subgroup analyses demonstrated that both types of peginterferon (α-2a and α-2b) achieved higher sustained response rates compared with interferon. The combination of peginterferon plus ribavirin was more effective than peginterferon monotherapy. High-dose or low-dose ribavirin with peginterferon demonstrated significantly higher sustained response rates when compared to interferon. Peginterferon plus ribavirin remained superior to interferon by genotype, although efficacies varied.
There were no significant differences between the groups for adverse events.