Trial Evaluating the Efficacy and Safety of Oral Vadadustat Once Daily (QD) and Three Times Weekly (TIW) for the Maintenance Treatment of Anemia in Hemodialysis Subjects Converting From Erythropoiesis-Stimulating Agents (ESAs)

Inclusion Criteria

• Receiving chronic, outpatient three times weekly (TIW) in-center hemodialysis for end-stage renal disease for at least 12 weeks prior to Screening
• Hemodialysis adequacy as indicated by single-pool Kt/Vurea ≥ 1.2 using the most recent historical measurement within 8 weeks prior to or during Screening
• Use of any approved erythropoiesis-stimulating agents (ESAs) for at least the 8 weeks prior to Screening Visit 2
• Two hemoglobin (Hb) values, at least 4 days apart, measured by the central laboratory during Screening within the following prespecified ranges:
• Hb values between 8.0 and 11.0 grams per deciliter (g/dL) (inclusive) in the United States;
• Hb values between 9.0 and 12.0 g/dL (inclusive) in Europe
• Serum ferritin ≥ 100 nanograms per milliliter (ng/mL) and transferrin saturation (TSAT) ≥ 20% during Screening
• Folate and vitamin B12 measurements ≥ lower limit of normal during Screening

Exclusion Criteria

• Anemia due to a cause other than chronic kidney disease (e.g., sickle cell disease, myelodysplastic syndromes, bone marrow fibrosis, hematologic malignancy, myeloma, hemolytic anemia, thalassemia, or pure red cell aplasia)
• Participants meeting cut-off of the following equivalent mean weekly doses calculated over 8 weeks prior to Screening Visit 2
• Methoxy polyethylene glycol-epoetin beta > 50 micrograms (µg)/week;
• Darbepoetin alfa > 100 µg/week;
• Epoetin analogues > 23000 International Units (IU)/week
• Active bleeding or recent blood loss within 8 weeks prior to randomization
• Red blood cell transfusion within 8 weeks prior to randomization
• Current uncontrolled hypertension.
• Acute coronary syndrome (hospitalization for unstable angina or myocardial infarction), surgical or percutaneous intervention for coronary, cerebrovascular or peripheral artery disease (aortic or lower extremity), surgical or percutaneous valvular replacement or repair, sustained ventricular tachycardia, hospitalization for heart failure (HF) or New York Heart Association Class IV HF, or stroke within 12 weeks prior to or during Screening.
• Known hypersensitivity to vadadustat, darbepoetin alfa, or any of their excipients