Antiviral response of HCV genotype 1 to consensus interferon and ribavirin versus pegylated interferon and ribavirin.

Achieving an antiviral response at a reasonable cost is a challenge in the treatment of patients with chronic hepatitis C. A previous study indicated that consensus interferon with ribavirin had promising activity against hepatitis C virus (HCV) genotype 1. The objective of this study was to determine the virologic response with consensus interferon or pegylated interferon alpha-2b plus weight-ribavirin in patients chronically infected with HCV genotype 1. Intention-to-treat analysis showed response in 37% and 41% of subjects treated with consensus interferon/ribavirin or pegylated interferon/ribavirin, respectively, with response rates of 42% and 44% observed in analysis of the per-protocol population, not a significant difference. Tolerability of the two treatment regimens was similar. In conclusion, both treatment regimens were safe and gave a similar antiviral response. It is possible that if consensus interferon is administered daily rather than three times weekly, eradication of HCV could be achieved in a larger proportion of patients infected with HCV genotype 1.

Peginterferon alfa-2b and weight-based or flat-dose ribavirin in chronic hepatitis C patients: a randomized trial.

UNLABELLED: This prospective, multicenter, community-based and academic-based, open-label, investigator-initiated, U.S. study evaluated efficacy and safety of pegylated interferon (PEG-IFN) alfa-2b plus a flat or weight-based dose of ribavirin (RBV) in adults with chronic hepatitis C. Patients (n = 5027) were randomly assigned to receive PEG-IFN alfa-2b 1.5 microg/kg/week plus flat-dose (800 mg/day) or weight-based (800-1400 mg/day) RBV for 48 weeks (patients with genotype 1, 4, 5, or 6) and for 24 or 48 weeks (genotype 2/3 patients). Primary end point was sustained virologic response (undetectable [<125 IU/mL] serum hepatitis C virus RNA at 24-week follow-up). Sustained virologic response, but not end-of-treatment, rates were significantly higher with weight-based than with flat-dose RBV (44.2% versus 40.5%; P = 0.008). Sustained virologic response rates by intention-to-treat analysis were 34.0% and 28.9%, respectively, in genotype 1 patients (P = 0.005) and 31.2% and 26.7%, respectively, in genotype 1 patients with high baseline viral load (P = 0.056). In genotype 2/3 patients, rates were not significantly different (61.8% and 59.5%, respectively) regardless of treatment duration. Besides greater hemoglobin reductions with weight-based RBV, safety profiles were similar across RBV dosing groups, including the 1400-mg/day group. CONCLUSION: PEG-IFN alfa-2b plus weight-based RBV is more effective than flat-dose RBV, particularly in genotype 1 patients, providing equivalent efficacy across all weight groups. RBV 1400 mg/day is appropriate for patients 105 to 125 kg. For genotype 2/3 patients, 24 weeks of treatment with flat-dose RBV is adequate; no evidence of additional benefit of extending treatment to 48 weeks was demonstrated.