Chronotherapeutic Circadian-Based Pulsatile Drug Delivery of Etodolac for Morning Stiffness in Rheumatoid Arthritis

This study focuses on the development of chronomodulated delivery systems for Etodolac, aimed at optimizing therapeutic outcomes in rheumatoid arthritis management. Core and coated microparticles were formulated using chitosan and Eudragit polymers, employing varying drug-to-polymer ratios and stirring speeds to achieve precise release profiles. Scanning electron microscopy confirmed the uniformity and integrity of the microparticles, with particle sizes ranging from 20.52 ± 0.79 µm to 105.45 ± 6.74 µm. Encapsulation efficiencies reached up to 98.34 ± 0.09% in coated formulations, demonstrating enhanced drug retention. Drug release studies revealed that coated microparticles followed controlled and sustained release patterns, aligning with zero-order and Higuchi kinetics, suitable for chronomodulated delivery. FTIR analysis confirmed chemical compatibility between Etodolac and excipients, ensuring formulation stability. The findings indicate that optimized formulation parameters, including drug-to-polymer ratios, stirring speeds, and polymer coatings, enabled effective delivery aligned with rheumatoid arthritis chronotherapy, targeting peak symptoms in early morning hours. This study highlights the potential of Etodolac microparticles for tailored drug delivery, improving patient compliance and therapeutic efficacy in managing rheumatoid arthritis.