Thirty percent of the overall cohort had week 24 VR. CART identified useful baseline predictors for subgroups with higher or lower frequencies of week 24 VR. All percentages indicate classified subjects with week 24 VR compared to the total subjects in that classified group. IL-10 Sum-HCV = sum of interleukin (IL)-10 responses to hepatitis C virus (HCV) proteins core, NS3 and NS5. Numbers associated with immune response data represent spot-forming cells (SFC)/106 peripheral blood mononuclear cells. IDU, injection drug users; IFN, interferon alfa-2a; PEG-IFN, pegylated interferon alfa-2a; RBV, ribavirin.