Comparative bioequivalence study between a novel matrix transdermal delivery system of fentanyl and a commercially available reservoir formulation

Aim To determine the pharmacokinetics, safety and performance of a novel matrix formulation of fentanyl. Methods Transdermal fentanyl was administered as the novel matrix and the Durogesic® reservoir formulations (24 subjects, 100 µg h−1) in a randomized, fully replicate, four‐way crossover study. Serum concentrations of fentanyl were assayed by LC/MS/MS. Pharmacokinetic parameters of fentanyl and performance (adherence and skin irritability) were evaluated. Results Test/reference ratio (90% confidence intervals) for AUC0–t, AUCinf and Cmax were 105.5% (99.4, 112.0), 105.3% (99.3, 111.6) and 111.4% (100.4, 123.6), respectively. Adherence and skin irritability results of the two formulations were similar. Conclusion The two formulations are expected to result in similar efficacy for the management of severe pain.