Pegylated alpha-interferon-2a plus ribavirin compared with pegylated alpha-interferon-2b plus ribavirin for initial treatment of chronic hepatitis C virus: prospective, non-randomized study.

Objective: We assessed whether the two regimens of pegylated alpha-interferon-2b (PEG-IFN-alpha2b) plus ribavirin and pegylated alpha-interferon-2a (PEG-IFN-alpha2a) plus ribavirin showed differences in terms of sustained virological response, withdrawal due to side-effects and dose adjustment requirements in the treatment of naive chronic hepatitis C virus (HCV) patients.

Methods: A prospective non-randomized, open-label comparison was made of naive HCV-infected patients undergoing standard 24- or 48-week treatment with two PEG-IFN combined with weight-based dosing regimen of ribavirin (PEG-IFN-alpha2a/ribavirin, n = 91; PEG-IFN-alpha2b/ribavirin, n = 92).

Results: Sustained virological response was similar in PEG-IFN-alpha2a and PEG-IFN-alpha2b (65.9% vs 62%, P = 0.64), without differences according to genotype. In 117 patients with HCV genotype 1, the corresponding rates were 50.8% versus 46.6% (P = 0.713). Rapid virological response at 4 weeks, early virological response at 12 weeks and transient virological response were also similar. In the multivariate analysis, HCV genotype (odds ratio [OR] = 0.076, 95% confidence interval [CI] 0.029-0.198, P = 0.000) and presence of steatosis in the liver biopsy (OR = 2.799, 95% CI 1.362-5.755, P = 0.005) were significantly associated with response to antiviral therapy. The rate of withdrawals due to treatment-related adverse events was 13.2% in the group of PEG-IFN-alpha2a and 10.9% in the group of PEG-IFN-alpha2b. Dose modification of PEG-IFN was necessary in eight patients given PEG-IFN-alpha2a and in seven given PEG-IFN-alpha2b.

Conclusions: The two PEG-IFN plus ribavirin have comparable anti-HCV activity as shown by similar percentages of patients with sustained virological response.