Intra-articular treatment of osteoarthritis using novel biocompatible etoricoxib chitosan-hyaluronate hybrid microparticles

The current study aimed to develop and evaluate Etoricoxib (ETX) loaded polyelectrolyte microparticles (PEMPs) for intra-articular delivery in osteoarthritis management. PEMPs were prepared by the electrostatic interactions between hyaluronic acid (HA) and chitosan (CS). The optimum formulation was characterized for encapsulation efficiency, particle size (PS), zeta potential (ZP), drug release, stability, TEM, FTIR, DSC and in vivo anti-inflammatory activity. The optimum formulation (ME4/TPP0.25) demonstrated spherical particles with a PS of 1.56 ± 0.04 µm, a PDI value of 0.29 ± 0.05, ZP of +35.26 ± 0.9 mV, and EE% of 94.7 ± 0.24% and loading capacity of 11.7 ± 0.16% (w/w). In vivo studies demonstrated that ME4/TPP0.25 significantly suppressed knee joint swelling, and significantly reduced the levels of catabolic and inflammatory mediators (ALP and IL-6) compared to drug alone. These results suggest that the optimum ETX-loaded PEMPs could be a promising formulation for knee osteoarthritis management.