Piroxicam loaded polymer hybrid microspheres based tablets with modified release kinetics: Development, characterization and in vivo evaluation

Abstract

Piroxicam (PC) is a non-steroidal anti-inflammatory drug characterized by poor aqueous solubility and reported to cause and impart crucial GIT irritation, bleeding, peptic and duodenal ulcer. Engineering of PC loaded microcapsules and its surface modification using different polymers has become the popular approach to address the said issues. The purpose of the study was to develop new PC loaded gastro-protective polymer hybrid microspheres (PHM) with subsequent conversion to tablet dosage form having modified dissolution rate and improved bioavailability. The crystallinity of the PC loaded PHM were established through powder X-ray diffraction. The optimised microspheres, PCM1 with particle size 32±3.0µm, entrapment efficiency 83.78±2.5% and in vitro drug release 87.1±2.6% were further subjected to tablets development and in vivo evaluation. The in vitro drug release study conducted for PHM at pH media 1.2 and 6.8 demonstrated retarded and enhanced drug release rates (P<0.001) respectively. Both accelerated and real time stability studies confirmed stability of the PC loaded PHM based tablets. A substantial improvement in the drug plasma concentration 12.6±2.36 (P<0.001) was observed for the produced tablets compared to the marketed formulations.