Randomized trial of combined triple therapy comprising two types of peginterferon with simeprevir in patients with hepatitis C virus genotype 1b

Simeprevir (SMV) is a potent, macrocyclic hepatitis C virus (HCV) non-structural 3/4 A protease inhibitor. This prospective study compared the efficacy and safety of SMV in combination with peginterferon α2a + ribavirin (P2aR) and with peginterferon α2b + ribavirin (P2bR) in Japanese patients with HCV genotype 1b infection. Methods Hepatitis C virus genotype 1b patients were randomly assigned to receive SMV (100 mg QD) with P2aR for 12 weeks, then P2aR alone for 12 or 36 weeks; or SMV (100 mg QD) with P2bR for 12 weeks, then P2bR alone for 12 or 36 weeks. The primary endpoint was a sustained virologic response 24 weeks after completing treatment (SVR24). Results In total, 151 patients were randomly assigned to the P2aR (n = 76) or P2bR group (n = 75). Six patients dropped out. Sustained virologic response 24 weeks after completing treatment was achieved in 55 (75.3%) of 73 P2aR patients and 55 (76.4%) of 72 P2bR patients. There was no difference in the rate of SVR24 between the two groups (P = 0.88). No differences in the proportion of patients who became HCV RNA-negative were detected between the P2aR and P2bR groups. The two groups had comparable numbers of adverse events, which led to the discontinuation of treatment in 9.6% and 8.3% of participants in the P2aR and P2bR groups, respectively. Conclusion Peginterferon α2a or α2b in combination with SMV + ribavirin therapy showed identical antiviral effects in patients with chronic hepatitis C. Also, the incidence of adverse events was identical for both regimens.