Investigation of Kinetic Drug Release Characteristics and In Vitro Evaluation of Sustained-Release Matrix Tablets of a Selective COX-2 Inhibitor for Rheumatic Diseases

Purpose The prevalence of rheumatic disease patients was estimated at 25% of the population. Rheumatic diseases are the leading cause of disability. The main objective of the study was to investigate the kinetic drug release characteristics of aceclofenac sustained-release (SR) matrix tablets for the management of rheumatic diseases. Methods The novel formulation of aceclofenac was prepared by using hydrophilic polymers such as HPMC K4M with a fixed concentration along with the varying concentration of Carbopol 946 and cationic guar gum in the formulation FA1-FA3 and FB1-FB3 respectively. The powder mixture was compressed by the direct compression method into tablets using a rotary tablet compression machine. Prepared SR matrix tablets were evaluated for uniformity of content, hardness, thickness, weight variation, friability, and in vitro dissolution studies. Results The drug content, hardness, thickness, weight variation, and friability of prepared tablets were found to be within the acceptable range. The optimized formulation was subjected to various kinetic release studies such as first-order model, zero-order model, Higuchi model, and Korsmeyer-Peppas model. When the data were plotted according to the Higuchi model, the formulations showed the best linearity, with regression values 0.9248 and diffusion mechanism of the formulation FB1 follows super case II transport mechanism. Conclusion The optimized formulation FB1 with the super case II transport mechanism prolonged the drug release, due to the polyionic interaction between the polymers. It could be an ideal formulation for the management of rheumatic diseases.