Transdermal fentanyl matrix patches Matrifen® and Durogesic® DTrans® are bioequivalent

AimThe pharmacokinetic profiles of the two commercially available transdermal fentanyl patches Matrifen® (100 μg/h) and Durogesic® DTrans® (100 μg/h), used to manage severe chronic pain, were compared regarding their systemic exposure, rate of absorption, and safety.MethodsTransdermal matrix fentanyl patches [Matrifen® or Durogesic® DTrans® (100 μg/h)] were applied for 72 h to 30 healthy male subjects in a randomized, four-period (two replicated treatment sequences), crossover study; 28 subjects completed the study. The pharmacokinetic parameters of fentanyl were determined for 144 h after application using plasma samples. Safety of the patches (adverse events) and performance (adhesion, skin irritation, residual fentanyl content in the patch) were evaluated.ResultsThe plasma concentration–time curves of Matrifen® (Test) and Durogesic® DTrans® (Reference) were similar. The geometric least square means of the Test/Reference ratio (90% confidence intervals [CI]) were within the range of 80–125%, demonstrating bioequivalence of Matrifen® and Durogesic® DTrans®: AUC0-tlast 92.5 (CI 88.7–96.4), AUC0-inf 91.7 (CI 88.0–95.7), and Cmax 98.3 (CI 92.9–104.1). After 72 h application, Matrifen® had a more efficient utilization of fentanyl (mean ± SD 82.3 ± 9.43%) than Durogesic® DTrans® (52.3 ± 12.8%), with substantially lower residual fentanyl in patch after use. The pharmacokinetic parameters showed lower intra- and inter-subject variability for Matrifen® than for Durogesic® DTrans® patch.ConclusionsDespite different technologies, the transdermal fentanyl patches Matrifen® and Durogesic® DTrans® are bioequivalent. Compared with Durogesic® DTrans®, the Matrifen® patch had lower initial and lower residual fentanyl content, as well as lower intra- and inter-subject variability, allowing reproducible drug delivery and reliable analgesia.