Hepatitis C virus Core Antigen as a predictor of non-response in genotype 1 chronic hepatitis C patients treated with peginterferon α-2b plus ribavirin

Background/Aims Chronic hepatitis C patients infected by genotype 1 are the least responsive to combination therapy and therefore monitoring response is important in identifying non-responders quickly, permitting therapy discontinuation and avoiding side effects and costs. We examined the usefulness of measuring total HCV Core Ag in early treatment with peginterferon α-2b and ribavirin in genotype 1 patients in the prediction of response and compared the results with those from HCV RNA quantification. Methods Two hundred and sixty-eight serum samples from 46 genotype 1 patients receiving combination therapy were examined for HCV Core Ag and quantitative HCV RNA. Results At baseline, mean HCV RNA and HCV Core Ag concentrations were significantly lower in sustained virologic responders than in non-responders. The negative predictive value of HCV Core Ag testing in predicting non-response at week 12 is 100%, and for a 2 log drop in HCV RNA, using two quantitative tests, it is 88%. Conclusions HCV Core Ag determination allows the identification of non-responders with only one test at week 12 and permits stopping therapy in these patients. HCV Core Antigen testing is cheaper and easier to perform than HCV RNA quantification.