A pharmacokinetic/pharmacodynamic study of controlled-release oxycodone.

Author(s): Benziger DP, Miotto J, Grandy RP, Thomas GB, Swanton RE, Fitzmartin RD

Affiliation(s): Department of Pharmacokinetics and Drug Metabolism, Purdue Pharma L.P., Yonkers, New York 10701, USA.

Publication date & source: 1997-02, J Pain Symptom Manage., 13(2):75-82.

Publication type: Clinical Trial; Randomized Controlled Trial

A single-dose, analytically blinded, randomized, crossover study was conducted in 22 healthy male volunteers to compare the bioavailability of one 20 mg with two 10 mg controlled-release (CR) oxycodone tablets. In addition, pharmacodynamic effects were assessed using both objective and subjective measures for up to 48 hr after dosing. The two treatments were bioequivalent, with comparable rates (Cmax of one 20 mg tablet was 109% of two 10 mg tablets; 90% confidence limits: 98.4%-120%) and extents (AUC0-infinity: 107%; 100%-114%) of absorption. In addition, no significant differences between tablets were found for mean values of Tmax, T/12abs, or T/12elim. Correlations between plasma oxycodone concentrations and most pharmacodynamic measures were significant. The strongest correlations were observed for pupil size (r = -0.53) and subjects' assessment of drug effect (r = 0.53), with changes in plasma concentration accounting for more than 25% of the observed changes in these variables. This study demonstrated bioequivalence of two 10 mg and one 20 mg CR oxycodone tablet, with significant correlation between plasma oxycodone concentrations and pharmacodynamic effects in normal volunteers.