IL-28B polymorphisms and treatment response in hepatitis C virus patients with persistently normal alanine aminotransferase

AIM:To examine the association between the interleukin 28B(IL-28B)genotype and treatment response in hepatitis C virus(HCV)-infected patients with persistently normal alanine aminotransferase(PNALT).METHODS:We compared the treatment response of HCV-infected patients with PNALT to that of patients with non-PNALT.Between February 2010 and April2013,278 patients infected with HCV were enrolled in this study.All of the patients were treated with peginterferon-alpha 2a or 2b plus ribavirin.In addition,180μg of peginterferon alpha-2a or 1.5μg/kg peginterferon alpha-2b per week plus weight-based ribavirin(600-1000 mg/d)were typically administered for 24 wk to HCV genotype 2-infected patients or for 48-72 wk to HCV genotype 1-infected patients.In all of the patients,the IL-28B rs8099917 genotype was determined using a TaqMan single-nucleotide polymorphism assay.HCV RNA was measured using the COBAS TaqMan HCV test.RESULTS:Female patients were dominant in the PNALT group(P<0.0001).Among 72 HCV genotype 1-infected patients with PNALT,the early virologic response(EVR)rates(P<0.01)and the sustained virologic response(SVR)rates(P<0.01)were higher in patients with the IL-28B TT genotype than in those with the IL-28B TG/GG genotype.In HCV genotype 1-infected patients with PNALT,multivariate logistic-regression analysis showed that SVR was independently predicted by the IL-28B rs8099917 TT type(P<0.05)and having an EVR(P<0.01).The IL-28B rs8099917 TT genotype strongly correlated with treatment response in HCV genotype 1-infected Asian patients with PNALT.CONCLUSION:The IL-28B genotype may be useful for selecting HCV genotype 1-infected patients with PNALT who should receive interferon-based treatment.