EPO and chronic kidney disease: With potentially beneficial attributes related to iron metabolism and hepcidin concentration22 and lower peak serum erythropoietin concentration,23 it was hoped that hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs) might provide viable alternative therapies for the treatment of anemia of CKD, particularly among ESA hyporesponsive patients.24 In our analyses, we did not find evidence for differential associations of baseline ESA hyporesponsiveness with MACE outcomes according to randomized treatment arm.