FORMULATION AND EVALUATION OF BILAYER TABLETS USING CO-CRYSTALS FOR IMPROVING DISSOLUTION RATE OF GLICLAZIDE

Abstract

Gliclazide is a second-generation sulfonylurea derivative widely used in the management of Type 2 Diabetes Mellitus. However, its therapeutic effectiveness is limited due to poor aqueous solubility and slow dissolution rate, resulting in dissolution-limited absorption and variable oral bioavailability. The present study was aimed at developing a novel bilayer tablet formulation of Gliclazide using pharmaceutical co-crystal technology to enhance dissolution rate and provide controlled drug release. Pharmaceutical co-crystals were prepared using suitable co-formers to modify the crystal properties of Gliclazide without altering its chemical structure. The optimized co-crystals were incorporated into the immediate-release layer to achieve rapid dissolution, whereas the second layer was formulated as a sustained-release matrix system to maintain prolonged drug release. The prepared bilayer tablets were evaluated for pre-compression parameters, post- compression characteristics, drug content, mechanical strength, and in-vitro dissolution behaviour. The developed formulation demonstrated satisfactory flow properties, acceptable tablet hardness, friability, weight uniformity, and thickness. Dissolution studies showed improved drug release characteristics compared with conventional Gliclazide formulations due to enhanced solubility of co-crystals and controlled release behaviour of the bilayer system. The developed formulation represents a promising approach for improving dissolution rate, enhancing bioavailability, reducing dosing frequency, and improving patient compliance in Type 2 Diabetes Mellitus management.