Single- and Multiple-Dose Pharmacokinetics of Immediate-Release/Extended-Release Ibuprofen Tablets.

A single-dose, randomized, open-label, crossover study (study 1; n = 35) and a multiple-dose, randomized, open-label, crossover study (study 2; n = 28) compared the pharmacokinetics of a new immediate-release/extended-release (IR/ER) bilayer tablet formulation of ibuprofen 600 mg every 12 hours with standard ibuprofen 200 mg IR every 4 hours. In both studies, the 2 formulations were bioequivalent to each other for the area under the plasma concentration-versus-time curve from time 0 to the last measurable concentration (AUCL), to infinity (AUC∞ ), and to 12 hours (AUC0-12 ) and maximum concentration (Cmax ). In study 1, food slowed the absorption of ibuprofen from ibuprofen 600 mg IR/ER (lower Cmax ) compared with the fasted state but did not affect the overall extent (AUC) of ibuprofen absorption. In study 2, there was no evidence of drug accumulation with multiple doses of ibuprofen IR/ER. In conclusion, ibuprofen 600 mg IR/ER provides a twice-daily over-the-counter analgesic option that is bioequivalent to standard ibuprofen 200 mg IR (every 4 hours) with regard to both the rate (Cmax ) and the extent (AUC) of absorption.