Randomized Study of Peginterferon-α2a Plus Ribavirin vs Peginterferon-α2b Plus Ribavirin in Chronic Hepatitis C

Background & Aims

Ribavirin (RBV) combined with either pegylated interferon (PegIFN) α2a or PegIFNα2b is the standard of care for chronic hepatitis C virus (HCV) infection. Due to the lack of head-to-head studies, the 2 PegIFNs have not been directly compared. The endpoints of our study were safety and antiviral efficacy of the 2 regimens.

Methods

Treatment-naïve patients with chronic hepatitis C were randomly (1:1) assigned after stratification for HCV genotype to receive either 1.5 mcg/Kg/week PegIFNα2b plus RBV 800–1200 mg/day or 180 mcg/week PegIFNα2a plus RBV 800–1200 mg/day for 24 or 48 weeks according to HCV genotype. The study was powered to detect a difference of at least 10% in safety and efficacy of the 2 regimens.

Results

The 212 patients on PegIFNα2a and the 219 patients on PegIFNα2b had similar baseline characteristics, including cirrhosis (20% vs 18%, respectively). By intention to treat, the 2 groups showed similar rates of treatment-related serious adverse events (1% vs 1%, respectively) and drop out rates for adverse effects (7% vs 6%, respectively). Overall, sustained virologic response (SVR) rate was higher in PegIFNα2a than in PegIFNα2b patients (66% vs 54%, respectively, P = .02), being 48% vs 32% in the 222 HCV-1 and -4 patients (P = .04), and 96% vs 82%, respectively, in the 143 HCV-2 patients (P = .01). PegIFNα2a independently predicted SVR in the logistic regression analysis (odds ratio, 1.88; 95% confidence interval: 1.20–2.96).

Conclusions

Although the 2 regimens showed a similar safety profile, the PegIFNα2a-based treatment yielded significantly more SVR than PegIFNα2b.

Abbreviations used in this paper: cEVR, complete early virologic response, ETR, end of treatment response, PegIFN, pegylated interferon, RBV, ribavirin, RVR, rapid virologic response, SVR, sustained virologic response