Pharmacokinetic and safety evaluations of ketoprofen gels in subjects with adult periodontitis.

This clinical trial used a randomized, partially double-blind, controlled parallel design to evaluate the pharmacokinetics and safety of the NSAID, ketoprofen (KTP), in gel formulations. Forty-two subjects, ages 35 to 57 years, with generalized, moderate to advanced adult periodontitis were recruited and randomized to one of 5 treatments over a 14 1/2-day treatment period: (1) 0.5% KTP gel; (2) 1.0% KTP gel; (3) 1.0% KTP alternate gel; (4) 2.0% KTP gel; and (5) 25 mg KTP capsule (positive control). Plasma samples were obtained on days 1 (pre-dosing, 0.5, 1, 2, 3, 6 hr), 8 (pre-dosing, 2 hr), 15 (pre-dosing, 2 hr), and 22 (7 days post-treatment). Plasma KTP concentrations were determined by means of high-performance liquid chromatography. Significant differences in mean area under the plasma concentration vs. time curve (AUC(0-infinity)) among the groups were detected (p < 0.001), with the 25 mg p.o. capsule exhibiting the largest value (5054 ng-hr/mL), the 2.0% gel exhibiting an intermediate value (2244 ng-hr/mL), the 1.0% gels exhibiting lower but comparable values (1516 for the alternate formulation vs. 1461 ng-hr/mL), and the 0.5% gel showing the lowest value (736 ng-hr/mL). Significant differences in dose- and weight-adjusted maximum plasma concentration (Cmax/dose/kg) were detected overall such that the 25 mg p.o. capsule demonstrated higher values as compared with the 4 gel formulations (p = 0.001). The 5 treatments exhibited similar mean times of maximum plasma concentration (tmax) values ranging from 0.6 to 1 hr. Systemic exposures relative to dose and body weight were lower for the gel formulations than for the capsule. The relative systemic bioavailability of the gels compared with peroral administration ranged from 54% to 69%.