To evaluate the superiority to placebo, dose-responsibility and safety.

This is a multi-center, randomized, double blind placebo-controlled and open label sevelamer hydrochloride-controlled, dose-ranging study in CKD patients with hyperphosphatemia on hemodialysis. Patients will be randomly allocated to one of the five treatment groups (ASP1585: 3 dose, placebo, Sevelamer hydrochloride) and advance to the 4-week treatment period.

Inclusion Criteria:

• Stable CKD patients who are currently on hemodialysis three times a week for at least 12 weeks prior to the acquisition of informed consent
• Patients on stable dose(s) of phosphate binder(s) for at least 28 days prior to the acquisition of informed consent.
• Patients on stable dose(s) of Vitamin D or calcitonin agent for at least 28 days prior to the acquisition of informed consent, in case patients are treated by those agents

Exclusion Criteria:

• History of major gastrointestinal surgery, or swallowing disorders, bowel obstruction, hemorrhagic gastrointestinal lesion
• Continuous severe constipation/diarrhea.
• History of parathyroid intervention [parathyroidectomy（PTx），percutaneous ethanol injection therapy（PEIT）etc.] within 1 year of the acquisition of informed consent
• Diet restriction such as fasting and/or excessive dieting
• Uncontrolled hypertension