Engineered Mucoadhesive Buccal Films of Repaglinide – Optimization and Quality Evaluation

Buccal mucosa is a potential site for the delivery of drugs to the systemic circulation in a sustained manner; avoiding the first-pass metabolism. The goal of present investigation was to design and evaluate mucoadhesive buccal films of Repaglinide in order to avoid first-pass effect and release the drug for extended period of time. The Buccal films were formulated using polymers, Carbopol-971P and HPMC K4M, by solvent casting method; using PEG 400 as plasticizer. In this study, an attempt has been made to prepare Repaglinide inclusion complex; to enhance its solubility and was incorporated into the mucoadhesive buccal films in order to improve the bioavailability. A comparative study has been done between; uncomplexed Repaglinide loaded buccal films and inclusion complex loaded buccal films. The films prepared were evaluated for various physicochemical parameters and in vitro drug release. It was observed that inclusion complex loaded buccoadhesive films showed higher cumulative percentage of drug release at the end of 8 hours. The release data obtained was analyzed using various mathematical models. The Repaglinide loaded films followed zero order kinetics with principle mechanism of drug release being fickian diffusion. Whereas the inclusion complex loaded films followed zero order kinetics and exhibited non-fickian diffusion mechanism. HCC1 formulation having acceptable physicochemical parameters and with highest cumulative percentage of drug release (95.18%) at the end of 8 hours was chosen as optimum formulation and its short term stability studies revealed adequate stability of the formulation.