Extended-release wax-matrix nicotinic acid shows preferred pharmacokinetic profile, study shows

Summary

This study was designed to compare the pharmacokinetics of extended-release wax-matrix nicotinic acid (WMNA) tablets and Nicobid, a prescription controlled-release niacin drug. Liver metabolism of nicotinic acid was measured by 24-hour urinary recovery of nicotinic acid and its major metabolite nicotinuric acid.

For this open-label, crossover study, the researchers enrolled 12 healthy men, mean age 32 years (range: 27 to 44) who were free of medication for the 2-week period prior to the onset of the study. All but one subject met the inclusion criteria.

Eleven men were given a single oral dose of nicotinic acid (500 mg) after a 12-hour fast as either WMNA or prescription niacin, separated by a 3-day washout period. Aspirin (325 mg) was given one hour prior to treatment to minimize flushing. Urine was collected immediately prior to ingestion and at regular intervals for the following 24-hour period. One subject was excluded due to contamination issues with urine testing, leaving data from 10 men for analysis.

A separate in-vitro dissolution test confirmed controlled-release profiles for both products with WMNA exhibiting a more rapid dissolution rate than prescription niacin.

Compared to prescription niacin, WMNA resulted in a more rapid rate of appearance of nicotinic and nicotinuric acid in the urine. In addition, WMNA resulted in a significant (P<.05) two-fold increase in the total amount of nicotinic and nicotinuric acids recovered in the urine after 24 hours compared to the prescription niacin. These findings suggest WMNA has greater metabolic conversion in the liver, which may correlate with clinical efficacy for the treatment of dyslipidemia.