Extended-release wax-matrix nicotinic acid tablets exhibit superior dissolution profile, study shows
Highlights
- Comparison of 19 niacin supplements
- Significant variation in dissolution profiles reported
- Extended-release wax-matrix nicotinic acid tablets exhibit the preferred dissolution profile
Summary
This study was designed to compare the dissolution profiles of extended-release wax-matrix nicotinic acid (WMNA) tablets, other non-prescription extended-release (ER) niacin supplements and inositol niacinate supplements. A prescription ER niacin drug (Niaspan) was chosen as the reference due to its extensive pre-market safety and efficacy review by the FDA.
A total of 19 commercially available supplements were evaluated, including 7 extended-release nicotinic acid supplements and 12 inositol niacinate supplements. (Inositol niacinate is the so-called “flush free” form of niacin introduced to the market with the intent of improving the tolerability of niacin, even though these products are not recommended for the treatment of dyslipidemia.) The free niacin content of powder (equivalent to 500 mg niacin) was measured according to the official U.S. Pharmacopeia monograph.
Results indicate significant variations in dissolution profiles among the 19 supplements. Of the 12 inositol niacinate products, a high variation in niacin release was found, ranging from 6% to 34% at 240 minutes. Of the seven ER supplements, one failed to demonstrate extended release, and five had dissolution profiles that were significantly (P<.05) higher than that of the prescription drug (mean 98 to 369 mg/hr vs. 90 mg/hr, respectively). Only WMNA tablets had a dissolution profile similar to that of the prescription drug (mean 93 mg/hr vs. 90 mg/hr, respectively).
These findings indicate that wide variability exists in dissolution profiles among extended-release niacin dietary supplements. Only WMNA tablets exhibited a dissolution profile similar to that of prescription ER niacin.