Peginterferon alfa-2b therapy in acute hepatitis C: impact of onset of therapy on sustained virologic response.

Pegylated interferon therapy has not been adequately evaluated in acute hepatitis C virus (HCV) infection. This randomized trial assessed the efficacy, safety, and timing of pegylated interferon alfa-2b for treatment of acute hepatitis C. One hundred seventy-five patients acutely infected with HCV were screened. Patients whose infection did not spontaneously resolve by week 8 were randomized to once weekly peginterferon alfa-2b monotherapy (1.5 microg/kg per week) started at weeks 8, 12, or 20 for a duration of 12 weeks. The primary endpoint was undetectable HCV RNA 24 weeks after the end of treatment (sustained virologic response [SVR]). All patients were followed for 48 weeks after cessation of therapy. One hundred twenty-nine subjects started treatment at week 8 (group A, n = 43), week 12 (group B, n = 43), or week 20 (group C, n = 43). By using an intent-to-treat analysis, the overall SVR rate was 87%. The SVR rates were 95%, 92%, and 76% with treatment onset at 8, 12, and 20 weeks, respectively. Overall, SVR rates were better for patients infected with genotypes 2, 3, and 4 than those infected with genotype 1. Earlier initiation of therapy improved SVR rates for patients infected with genotype 1 with high viral load. Peginterferon alfa-2b was well tolerated. Subjects with SVR maintained undetectable HCV RNA 48 weeks after therapy. Peginterferon alfa-2b monotherapy in acute hepatitis C induces high sustained virologic response rates, prevents chronic evolution, and is well tolerated. Initiation of treatment at week 8 or 12 results in higher sustained virologic rates than initiation at week 20.