Phase III Randomized, Double-Blind Study of Potassium Phosphate Vs Potassium Citrate for Absorptive Hypercalciuria

Sponsor

National Center for Research Resources (NCRR) (NIH)

Overall Status

Completed

CT.gov ID

NCT00004284

Collaborator

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (NIH), University of Texas (Other)

300

Enrollment

Study Details

Study Description

Brief Summary

OBJECTIVES: I. Evaluate the ability of a slow-releasing formulation of neutral potassium phosphate to correct hypercalciuria and prevent recurrent stone formation in patients with absorptive hypercalciuria.

Evaluate the safety of this treatment. III. Compare the efficacy of potassium phosphate to that of potassium citrate.

Condition or Disease	Intervention/Treatment	Phase
Hypercalciuria Kidney Calculi	Drug: potassium citrate Drug: potassium phosphate	Phase 3

Detailed Description

PROTOCOL OUTLINE: This is a randomized, double-blind study. Patients are stratified by participating institution.

Patients receive potassium phosphate or potassium citrate tablets twice a day for 3 years.

Study Design

Study Type:

Interventional

Allocation:

Randomized

Masking:

Double

Primary Purpose:

Treatment

Study Start Date :

Apr 1, 1995

Outcome Measures

Primary Outcome Measures

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics-- Absorptive hypercalciuria Intestinal hyperabsorption of calcium, i.e.: Exaggerated calciuric response to oral calcium load OR Fractional calcium-47 absorption greater than 0.61 Calciuria greater than 200 mg/day on random and calcium-restricted diet Normal or high fasting urinary calcium Normal serum calcium Normal serum parathyroid hormone No primary hyperparathyroidism At least 1 calcium oxalate stone within the past 3 years No struvite or carbonate apatite stones No noncalcareous stones No numerous stones making precise quantitation difficult No renal tubular acidosis --Prior/Concurrent Therapy-- No concurrent drug therapy for nephrolithiasis --Patient Characteristics-- Creatinine clearance at least 0.7 mL/min per kilogram No hyperkalemia No hyperphosphatemia No urinary tract infection Other: No predisposition to hyperkalemia, including concurrent use of the following drugs: Potassium-sparing diuretics Angiotensin-converting enzyme inhibitors Nonsteroidal anti-inflammatory drugs No active peptic ulcer disease No chronic diarrhea