RATIONALE & OBJECTIVE: Prespecified analyses of the PRO STUDY DESIGN: Phase 3, global, open-label, randomized, active-controlled clinical trial. SETTING AND PARTICIPANTS: Erythropoiesis-stimulating agent-untreated patients with anemia and NDD-CKD. INTERVENTION: Eligible patients were randomized 1:1 to receive vadadustat or darbepoetin alfa. OUTCOMES: The primary safety end point was time to first MACE.