A Phosphate Binder Switch Study of KHK7791 in Hyperphosphatemia Patients on HD

Study Overview
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Brief Summary
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To evaluate the effect and safety of a switch from phosphate binders to KHK7791 to treat Hyperphosphatemia in patients on HD.

Official Title
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A Phase 2, Open-label Phosphate Binder Switch Study of KHK7791 in Hyperphosphatemia Patients on Hemodialysis

Conditions
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Hyperphosphatemia

Intervention / Treatment
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* Drug: KHK7791


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Stable chronic renal failure patients who have undergone hemodialysis 3 times per week for at least 12 weeks until screening examination. Met certain conditions for dialysis excluding Dry Weight (Dialysate, Dialyzer, Frequency of Dialysis per Week, Dialysis Time, Blood Flow Rate, and Dialysate and Substitution Fluid Flow Rate) 2 weeks before screening examination. Taking at least 2 tablets of phosphate binder 3 times per day. The prescribed dosage regimen should have been unchanged for the period from 2 weeks before screening examination through pre-enrollment. Serum phosphorus levels should be between 3.5 and 7.0 mg/dL (inclusive) at screening examination. If on any vitamin D or calcimimetics regimen, the dosage regimen should have been unchanged for the last 2 weeks before screening examination. Exclusion Criteria: iPTH > 600 pg/mL (should be based on the most recent value from patient's medical records before pre-enrollment) History of inflammatory bowel disease (IBD) or diarrhea predominant irritable bowel syndrome History of gastrectomy or enterectomy (excluding endoscopic resection and cecectomy) or having undergone gastrointestinal tract surgery within 3 months before screening examination. Severe heart disease (including congestive heart failure, defined as New York Heart Association [NYHA] cardiac functional classification of Class III or IV, and vascular lesions requiring hospitalization such as myocardial infarction), hepatic impairment (including AST/ALT ≥ 100 U/L before the start of observation period), or concurrent cirrhosis. Developed cerebrovascular disease (such as cerebral infarction and cerebral hemorrhage) or cardiovascular disease (such as acute myocardial infarction and unstable angina) requiring hospitalization within 6 months before screening examination. Uncontrollable hypertension or diabetes Scheduled for living donor kidney transplant, change in the mode of dialysis, home hemodialysis or plans to change the dialysis center (relocate to another hospital/clinic) during the study period. Any diagnosis of or treatment of malignancy within 5 years before screening examination (excluding basal cell carcinoma or surgically resected intraepithelial carcinoma of uterine cervix).

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 79 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: KHK7791<br>Patients start at KHK7791 30 mg BID and can down titrate weekly to 20, 15, 10, and 5 mg BID, sequentially based on a GI tolerability question. | Drug: KHK7791<br>* KHK7791 30 mg, 20 mg ,10 mg or 5 mg tablets<br>* Other names: Tenapanor;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of subjects who reduce the total number of taking phosphate binder tablets at the last assessment from baseline. |  | Week 26 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum phosphorus levels at each time point after the start of treatment |  | up to Week 26 | 
| Corrected serum calcium level at each time point after the start of treatment |  | up to Week 26 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tenapanor, Hyperphosphatemia, Hemodialysis