Formulation, Optimization and Characterization of Transdermal Patch of Repaglinide

Abstract

The purpose of the study was development of matrix-type transdermal therapeutic system containing Repaglinide. Repaglinide has half life of 1 hour, and 56 % bioavailability in the body.Total daily dose of Repaglinide is 4 mg (e.g., 1 mg four times daily); hence, it requires frequent dosing. Transdermalpatch of Repaglinide was prepared to sustain the release and improve bioavailability of drug and patient compliance.Drug purity was confirmed by using FTIR and melting point determination. Differentformulations were prepared using various concentrations of HPC-EF and Duro-Tak 87-9301 as polymer using solvent casting method. All formulation carried 20 % of PEG 400 as plasticizer and IPM as penetration enhancer. Prepared formulations were evaluated for various parameters like thickness, tensile strength, folding endurance, % elongation, %moisture content,%moisture uptake, % drug content, in vitro- ex vivo drug release, and in-vivo study. Batch H5 containing 10% w/v of HPC-EF and 10% w/v of IPM showed maximum in-vitro (92.41%) and ex-vivo (90.86%) drug release at 24 hr, as compared to batch D5 (80% w/w of Duro-Tak 87-9301 and 10% of IPM) as polymer.Higuichi model showed maximum r2 value (0.954) so diffusion could be best expressed by Higuchi’s equation for the release of drug that depends mostly on diffusion characteristic.In vitro and exvivo correlation study was performed which indicated in-vitro diffusion profile was similar to ex-vivo diffusion profile.Batch B2 (5 % of PVA) showed maximum tensile strength and % percentage elongation so it was selected as backing layer. Adhesive layer was prepared using 2 % w/w of Duro-Tak 87-9301 as PSA. In vivo study (skin irritation study and patch adherenc