Using logistic regression analysis on pooled data from the ribavirin-containing treatment arms, the association of anemia with the following factors was explored: gender, age (<60 years vs ≥60 years), weight (<75 kg vs ≥75 kg), body mass index (<25 kg/m2 vs ≥25 kg/m2), fibrosis stage (F0–F2 vs F3–F4), presence of cirrhosis (yes/no), baseline hemoglobin (<15 g/dL vs ≥15 g/dL), rs6051702 genotype (ITPA-deficient (CC/CA) vs ITPA-non-deficient (AA])), initial ribavirin dose, and faldaprevir, deleobuvir, and ribavirin trough concentrations through week 12. Here, ITPA is linked to Cirrhosis.