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.