Treatment efficacy of pegylated interferon plus ribavirin therapy in chronic hepatitis C patients with mixed genotype 1/2 infection

Background and AimThe treatment efficacy of patients with mixed hepatitis C virus (HCV) genotype 1/genotype 2 (HCV-1/2) remains unknown. We aimed to elucidate the sustained virological response (SVR) rate in patients with HCV-1/2 infection. MethodsOne hundred and ten HCV-1/2 patients treated with response-guided peginterferon/ribavirin therapy (24 weeks for patients with a rapid virological response [RVR] and low viral loads; 48 weeks for patients without a RVR or high viral loads) were allocated. Two hundred HCV-1 patients were selected as a historical control. Interleukin-28B (IL-28B) rs8099917 genotype was tested for the association with an SVR. ResultsThe rates of RVR, sustained virologic response (SVR), and relapse rate were 71.8%, 87.3%, and 11.1%, respectively. The SVR rate was significantly higher in patients with an abbreviated regimen as compared with those with 48-week regimen (95.5% vs 75.0%, P=0.002), and both were similar to the HCV-1 historical control. Stepwise logistic regression analysis revealed that lower baseline viral loads were the single factor predictive of an RVR (odds ratio/95% confidence intervals [OR/CI] of 41.62/9.72-178.19, P<0.001). The achievement of an RVR was the single best factor predictive of an SVR (OR/CI: 7.5/1.33-42.27, P=0.02). Nevertheless, an abbreviated regimen became the single factor associated with an SVR if treatment regimen was taken into consideration (OR/CI: 11.0/1.25-96.79, P=0.03). The SVR rate did not differ between patients with rs8099917 TT and TG/GG genotype (91.7% vs 87.5%, P=0.63). ConclusionsThe treatment efficacy of patients with HCV-1/2 was satisfactory. The role of IL-28B genetic variants in the population with response-guided therapy was limited.