Preclinical Investigation of Transdermal Route for Enhanced Bio-performance of Duloxetine HCl

Abstract

The aim of the study was to develop and optimise drug-in-adhesive (DIA) transdermal patch of duloxetine HCl for enhanced drug delivery. DIA patch so developed reduced the dose and dosing frequency by enhancing bio-performance of the drug. A transdermal DIA patch having Duro-Tak 87-2287 as DIA polymer and Transcutol P as permeation enhancer loaded with 40% drug previously complexed with MeβCD duly characterised (FTIR, DSC, and SEM) was developed for in vivo study. Pharmacokinetic parameters of developed formulation were assessed and compared with oral route of administration. Among various permeation enhancers (PEs), Transcutol P exhibited most enhanced permeation (ER ≈ 1.99) in terms of flux and Q₂₄ compared to control group having. Mean of maximum plasma concentration (C_max) and area under time-concentration curve (AUC_0-72) in Wistar rats (n = 6) for transdermal patch (10 mg/kg) was found to be 70.31 ± 11.2 ng/ml and 2997.29 ± 387.4 ng/ml*h, respectively, and were considerably higher than oral dose of DLX (20 mg/kg and 10 mg/kg). Albeit, T_1/2 was higher in case of transdermal delivery, but this was due to sustained behaviour of delivery system. These findings highlight the significance of both inclusion complexation and transdermal delivery of DLX using DIA patch for efficient drug absorption.

Keywords: permeation enhancer; pharmacokinetics; poorly water-soluble drug; spray drying; transdermal.