Interleukin-28B gene non-TT allele strongly predicts treatment failure for genotype 1 infected chronic hepatitis C patients with advanced fibrosis: a case control study

BACKGROUND The role of single nucleotide polymorphisms (SNPs) of interleukin (IL)-28B in predicting therapeutic response of pegylated interferon (peg-IFN) plus ribavirin (PR) for genotype 1 infected chronic hepatitis C patients with advanced fibrosis (AF) is limited. The aim of this study is to assess its role in predicting sustained virologic responses (SVR) to treatment. METHODS Forty-two patients with biopsy proven hepatitis C virus (HCV) related AF (group A; Ishak fibrosis score, ≥4) and 126 sex- and HCV genotype-matched patients without AF (group B; Ishak fibrosis score, ≤3) were recruited into study. All patients received PR therapy for 24 weeks. Baseline and on-treatment clinical, virological and host factors were evaluated for treatment efficacy. RESULTS The SVR rate was significantly lower in group A than group B patients with genotype 1 infection (24% vs. 53.3%; p=0.011). However, it was similar in those with genotype non-1 infection (76.5% vs. 76.5%; p=1.0). IL-28B rs8099917 genotype TT is the strongest predictor for SVR in genotype 1 infection. Patients who had TT genotype and achieved RVR in group A had similar SVR rates with those in group B (44.4% vs. 53.3%; p=0.614). One third of patients in group A developed hematological adverse effects and had required modified doses during antiviral therapy. CONCLUSIONS In HCV genotype 1 infected AF receiving 24 weeks of PR treatment, patients with IL28B rs8099917 genotype TT, achieving RVR had similar SVR rate with those without AF. In contrast, patients with IL-28B rs8099917 non-TT genotype without achieving RVR are suggested to stop therapy.