Safety and antiviral activity of albinterferon alfa-2b dosed every four weeks in genotype 2/3 chronic hepatitis C patients

Background & Aims: A phase 2, randomized, multi-center, open-label study evaluated the safety and efficacy of albinterferon alfa-2b in interferon-alpha treatment-naive patients with genotype 2/3, chronic hepatitis C virus infection. Methods: Forty-three patients were randomly assigned in a 1:1 ratio to receive subcutaneous albinterferon alfa-2b 1500 mu g every 4 weeks (q4wk) or every 2 weeks (q2wk) with oral ribavirin 800 mg/day for 24 weeks. Primary efficacy end point was sustained virologic response (undetectable hepatitis C virus RNA 24 weeks after completion of treatment). Insulin resistance was also assessed. Results: The safety of albinterferon alfa-2b was acceptable, with a similar adverse event profile in both treatment arms. Discontinuation as a result of adverse events occurred in 4.5% and 14.3% of patients in the q4wk and q2wk arms, respectively. No dose reductions caused by adverse events were reported in the q4wk arm versus 9.5% in the q2wk arm. Rapid viral response rates at week 4 were 68.2% and 76.2% for the q4wk and q2wk arms, respectively; the corresponding sustained virologic response rates were 77.3% and 61.9%. Insulin resistance at baseline was significantly associated with lower sustained virologic response rates independent of body mass index. Conclusions: Albinterferon alfa-2b administered at 4-week intervals was safe and well-tolerated and demonstrated significant antiviral activity in patients with genotype 2/3, chronic hepatitis C virus. Insulin resistance appeared to have an independent effect on treatment response.