Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) may offer an alternative erythropoiesis-stimulating agents (ESA) for the treatment of anemia in the setting of CKD. To investigate the efficacy and safety of conversion from long-acting erythropoiesis-stimulating agent (ESA) methoxy polyethylene glycol-epoetin beta (MPG-EPO) to the oral hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) vadadustat 3-times-weekly versus maintenance on MPG-EPO.