Reduced dose and duration of peginterferon alfa-2b and weight-based ribavirin in patients with genotype 2 and 3 chronic hepatitis C.

Background & Aims: There is increasing interest in identifying patients with chronic hepatitis C genotype 2 or 3 infection in whom it is possible to lower the burden of therapy while retaining high levels of efficacy.

Methods: Treatment-naive patients with chronic hepatitis C genotype 2/3 infection were randomized to receive peginterferon alfa-2b (1.5μg/kg/wk) for 24weeks (group A); peginterferon alfa-2b (1.0μg/kg/wk) for 24weeks (group B); or peginterferon alfa-2b (1.5μg/kg/wk) for 16weeks (group C), each in combination with weight-based ribavirin (800-1200mg/d). The study population comprised two cohorts: the Hep-Net cohort enrolled in Germany and an International cohort enrolled at study sites throughout Europe and Asia. The primary end point was sustained virological response (SVR).

Results: The study included 682 patients; 80.2% had genotype 3 infection. In the intent-to-treat population, SVR rates were 66.5%, 64.3%, and 56.6% in groups A, B, and C, and were similar in Asian and white patients. Treatment differences (A vs. B and A vs. C) failed to reach the predefined margin for noninferiority of -10%; and thus groups B and C failed to show noninferiority relative to group A. Among patients with undetectable HCV RNA at week 4, SVR rates were 75.3%, 75.9%, and 72.4%, respectively. Relapse rates were 17.8%, 16.3%, and 29.3%, respectively. Treatment-emergent serious adverse events were highest in group A and lowest in group C, and adverse events leading to discontinuation were similar across treatment arms.

Conclusions: For patients with chronic hepatitis C genotype 2/3 infection, 24weeks of peginterferon alfa-2b (1.5μg/kg/wk) plus weight-based ribavirin remains a standard-of-care therapy; however, treatment for 16weeks may be considered for patients with undetectable HCV RNA at week 4 of the treatment.