Examination of Plasma Concentrations and Safety in Chronic Kidney Disease Patients Undergoing Hemodialysis

To examine the pharmacokinetics, pharmacodynamics and safety in patients with chronic kidney disease undergoing hemodialysis.

• To assess the pharmacokinetics (PK), pharmacodynamics (PD), safety and the effect of hemodialysis on PK of single oral administration of ASP7991 in Part 1.
• To assess the safety, PK and PD of repeated oral administration of ASP7991 in part 2.

Inclusion criteria

• Patients on stable chronic maintenance dialysis who are receiving hemodialysis therapy 3 times/week for more than 12 weeks (84 days) and are also scheduled to undergo the regimen of 3 times/week hemodialysis during the study period
• Patients who have secondary hyperparathyroidism;

• Receiving Active vitamin D or Cinacalcet hydrochloride
• OR iPTH values ≥ 180 pg/mL at screening in case patients receive no medication for secondary hyperparathyroidism.
• Corrected serum Ca at screening：≥ 8.4 mg/dL
• No changes in items below at least 7 days before screening and do not have a plan to change something in the items below during the trial.

• Dose and type of Active Vitamin D, Calcitonin preparation, Phosphate binder.
• Ca concentration of the dialysate, membrane area of the dialyzer and dialysis time of each week(possible to change within ±10%)

Exclusion criteria

• Patients who underwent parathyroid intervention within 24 weeks prior to the informed consent
• Patients who have primary hyperparathyroidism
• Having a history of gastric/intestinal resection considered influential on the absorption of the drug in the gastrointestinal tract
• Patients with uncontrolled hypertension (systolic blood pressure ≥ 180 mmHg and diastolic blood pressure ≥ 120 mmHg are showed at the previous three points at the initiation of dialysis including the screening assessment)
• Complicated by severe heart disorder [congestive cardiac failure (NYHA classification III or higher), or wide range of old myocardial infarction], or having a history of hospitalization for cerebro-vascular disease or heart disorder within 12 weeks(84 days) before obtaining the informed consent.
• Concurrent serious hepatic disease (acute and active chronic hepatitis, hepatic cirrhosis)
• History of malignant tumor
• History of serious drug allergy including anaphylactic shock
• Potentially child-bearing, lactating, those who do not comply with the instructed contraceptive measures
• Patients who were involved in an assessment of other clinical trial within 12 weeks(84 days) prior to the informed consent
• Patients who is an employee of the sponsor, CRO, SMO, or sites related to the study.
• Patients who have been judged ineligible to participate in the study by the investigator / sub investigator.