Combination therapy with peginterferon plus ribavirin has become the current standard of care for chronic hepatitis C (CHC) patients, with an overall sustained virologic response (SVR) rate of 54-63%. Treatment with weekly peginterferon and weight-based ribavirin for 48 weeks had a significantly higher SVR rate than that for 24 weeks in Caucasian patients with HCV genotype 1 infection (52% to 42%). Based on ample evidence from Western countries, a 48-week course of peginterferon plus weight-based ribavirin therapy is widely recommended to treat HCV genotype 1 infection in different parts of the world. However, recent studies for Asian CHC genotype 1 patients showed favorable treatment response to Caucasian patients with either 24 or 48 weeks of peginterferon plus weight-based ribavirin therapy (50 to 60% for 24 weeks; 75 to 80% for 48 weeks). In contrast, the overall SVR rates were similar across different ethnicity in patients with HCV genotype 2/3 infection.