Efficacy of peginterferon and ribavirin is associated with the IL28B gene in Korean patients with chronic hepatitis C

BACKGROUND/AIMS Sustained virologic response (SVR) for the treatment of chronic hepatitis C (CHC) may differ with ethnicity due to differences in genetic traits. This study evaluated the efficacy of peginterferon and ribavirin, and the association between IL28B genotypes and the treatment efficacy in Korean CHC patients. METHODS This was a retrospective cohort study using data from medical records. Eighty-five CHC patients were eligible for assessment of the efficacy of antiviral therapy, and 47 patients were available for an IL28B genetic study, which was performed using the Multiplex tetra-primer PCR method for rs12979860. RESULTS Overall, the early virologic response rate was 87.1%: 84.9% in HCV genotype 1 and 90.6% in genotype 2. The overall end-of-treatment virologic response rate was 81.2%: 75.5% in genotype 1 and 90.6% in genotype 2. The overall SVR rate was 81.2%: 75.5% in genotype 1 and 90.6% in genotype 2. For rs12979860, the frequencies of polymorphisms were 89% for the CC type, 11% for the CT type, and 0% for the TT type. Their overall SVR rate was 87% (39/47): 90.5% (38/42) for the CC type and 20% (1/5) for the CT type. For genotype 1, SVR rates were 88% (21/24) for the CC type and 0% (0/4) for the CT type. Multivariate analysis revealed that the IL28B-CC type was a good predictor for SVR. CONCLUSIONS The SVR of the combination therapy in Koreans was higher than that observed in Western countries. This finding might be attributable to the high prevalence of IL28B-CC type among Koreans, which may be a good predictor of SVR.