Pharmacokinetic evaluation of conventional and controlled-release product of naproxen

The bioavailability and pharmacokinetics of a new controlled-release tablet (CRT) of naproxen (750 mg tablet) have been determined, relative to an equivalent dose of conventional product (CT), by a cross-over study in twenty healthy volunteers. The two dosage forms were bioequivalent in terms of total AUC; however, the Cmax of the controlled-release product was lower, and the Tmax longer than that of the conventional product. The mean residence time and the absorption and elimination half-lives of the CRT were also substantially longer than those of the CT. The pharmacokinetic features offered by the novel formulation suggest that it may be suitable for once-daily dosing.