A Study to Investigate the Effect of ASP1517 After Intermittent Oral Dosing in Dialysis Chronic Kidney Disease Patients With Anemia Compared With Darbepoetin as a Reference Drug

Inclusion Criteria: * Patients who diagnosed as a end-stage kidney disease (ESKD) and are receiving stable chronic maintenance dialysis 3 times per week for ≥ 12 weeks * Patients who are receiving ESA for at least 8 weeks and the dose of ESA is within the dose range of ESA label * Hb value at screening test is ≥10.0 g/dL * Receiving hemodialysis via arteriovenous fistula (AVF) or arteriovenous graft (AVG) or via permanent catheter * Most recent two Hb values before dialysis during washout period must be both \<9.5 g/dL and one of two Hb values must be tested on first visit of the week Exclusion Criteria: * Proliferative retinopathy, age-related macular degeneration, retinal vein occlusion and/or macular edema that is considered to require treatment * Immunological disease with severe inflammation as assessed by the Investigator; even if the inflammation is in remission, the subject is excluded (e.g. lupus erythematosus, rheumatoid arthritis, Sjogren's syndrome, celiac disease, etc) * Having a history of gastric/intestinal resection considered influential on the absorption of the drug in the gastrointestinal tract or active gastroparesis * Uncontrollable hypertension (SBP ≥160 mmHg and DBP ≥110 mmHg, before dialysis, at screening test) * Congestive heart failure (NYHA classification III or higher) * Having a history of hospitalization for stroke, myocardial infarction or lung infarction within 24 weeks before 1st registration * Positive for any of the following: human immun…