The Effect of Oral Niacinamide on Plasma Phosphorus Levels in Peritoneal Dialysis Patients

Sponsor

Washington University School of Medicine (Other)

Overall Status

Completed

CT.gov ID

NCT00508885

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

1.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Hyperphosphatemia is common in the peritoneal dialysis population. Current strategies are insufficient to optimize phosphorus control. Animal studies have shown niacinamide, a form of vitamin B, to reduce phosphate uptake by the rat small intestine. Our trial investigates the use of niacinamide, in addition to standard phosphorus lowering strategies, to reduce plasma phosphorus levels in peritoneal dialysis patients versus placebo.

Condition or Disease	Intervention/Treatment	Phase
Hyperphosphatemia	Drug: Niacinamide Drug: Placebo	Phase 1/Phase 2

Detailed Description

This is a prospective, randomized, double-blind, placebo-controlled 8-week clinical trial to evaluate the efficacy of niacinamide versus placebo to reduce plasma phosphorus levels in peritoneal dialysis patients. Patients on a stable regimen of phosphate binders with plasma phosphorus levels > 4.9 mg/dL are eligible for enrollment and randomization. The study will span 8 weeks of active medication treatment. The primary end-point will be absolute change in plasma phosphorus levels. Sixteen patients (8 randomized to each treatment arm) are needed to detect a 1.5 mg/dL difference assuming a standard deviation of 1 and powered at 80% (alpha 0.05). Placebo will be packaged to resemble the study drug in all physical attributes. The starting dose of niacinamide will be 250 mg twice daily to be titrated to 500 mg twice daily at the end of week 2 with a final titration to 750 mg twice daily at the end of week 4. Secondary end-points will include absolute change in the calcium-phosphorus product, intact parathyroid hormone, hemoglobin, platelet count, total cholesterol, HDL cholesterol, and percentage change in plasma phosphorus.

Study Design

Study Type:

Interventional

Actual Enrollment :

17 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Double

Primary Purpose:

Treatment

Official Title:

The Effect of Oral Niacinamide on Plasma Phosphorus Levels in Peritoneal Dialysis Patients

Study Start Date :

Oct 1, 2006

Actual Study Completion Date :

Jul 1, 2007

Arms and Interventions

Arm	Intervention/Treatment
Experimental: 1 Niacinamide starting at 250 mg twice daily titrated up to 750 mg twice daily	Drug: Niacinamide Niacinamide 250 mg twice daily titrated up to 750 mg twice daily
Placebo Comparator: 2 Placebo	Drug: Placebo Placebo

Arm

Intervention/Treatment

Experimental: 1

Niacinamide starting at 250 mg twice daily titrated up to 750 mg twice daily

Drug: Niacinamide

Niacinamide 250 mg twice daily titrated up to 750 mg twice daily

Placebo Comparator: 2

Placebo

Drug: Placebo

Placebo

Outcome Measures

Primary Outcome Measures

The change in plasma phosphorus after 8 weeks of niacinamide versus placebo [8 weeks]

Secondary Outcome Measures

The change in intact parathyroid hormone, calcium-phosphorus product, cholesterol profile, and percentage change in plasma phosphorus [8 weeks]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Inclusion Criteria:

Age > 18 years
Capable of giving informed consent
Duration of peritoneal dialysis > 3 months
Dose of phosphate binder(s) stable over previous 2 week period
Plasma phosphours > 4.9 mg/dL based on most recent laboratory data within 1 month of enrollment

Exclusion Criteria:

Pregnancy
Known liver disease
Active peptic ulcer disease
Treatment with carbamazepine
Intolerance to niacinamide or niacin
Current medication regimen including niacin or niacinamide > 100 mg daily
Planned or expected surgical procedure in the next 4 months
Patients in nursing home or extended care facilities where administration of the study drug may not be appropriately given