Clinical Pharmacokinetics of Lofexidine, the [alpha] 2-Adrenergic Receptor Agonist, in Opiate Addicts Plasma Using a Highly Sensitive Liquid Chromatography Tandem Mass Spectrometric Analysis

The objective of this investigation was to characterize the pharmacokinetic profile of lofexidine. Lofexidine is an orally bioavailable α 2-adrenergic receptor agonist analogue of clonidine that acts centrally to suppress opiate withdrawal symptoms. During the detoxification period of a phase 3 placebo-controlled, randomized, double-blind trial, six subjects were entered in this preliminary pharmacokinetic study. Pharmacokinetic analysis of plasma samples collected during study day 7 indicated that C... was 3242 ± 917 ng/L. The mean trough levels between the study days were not significantly different (p > .05), suggesting that the subjects were at steady-state. Although preliminary due to the limited number of subjects, these findings are the first to document lofexidine clinical pharmacokinetics in opiate addicts using a highly sensitive liquid chromatography tandem mass spectrometric analysis. (ProQuest: ... denotes formulae/symbols omitted.)