Background/Aims Pegylated interferon (peginterferon) and ribavirin is the current standard therapy for chronic hepatitis C. The aims of this study were to evaluate the efficacy of peginterferon and ribavirin and to identify predictors of a sustained virological response (SVR) to the retreatment of chronic hepatitis C in Korea.MethodsThe clinical records of 91 patients with chronic hepatitis C who were retreated with peginterferon and ribavirin were retrospectively analyzed. None of the patients had previously attained a SVR, and the patients were categorized according to their previous responses (nonresponder, relapser, or inadequate treatment) to conventional interferon/ribavirin.ResultsThe overall SVR rate was 54.9%. Independent predictors of a SVR were genotypes 2 and 3, relapse, an adherence to peginterferon of over 80%, and an early virological response (EVR). For genotype 1 patients, an adherence to peginterferon of over 80% was an independent predictor of a SVR.ConclusionsPeginterferon and ribavirin therapy is effective for the retreatment of Korean chronic hepatitis C patients who have failed interferon/ribavirin, especially in patients with genotypes 2 and 3, relapse, an adherence to peginterferon over 80%, and an EVR. For genotype 1 patients, retreatment was effective in patients with an adherence to peginterferon over 80%.