Hydrogel-Based Strategies for Managing Rheumatoid Arthritis: From Sustained Drug Release to Cell-Based Therapies.

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent inflammation and joint damage, significantly impacting the quality of life. Traditional treatments for RA, including synthetic and biological disease-modifying antirheumatic drugs (DMARDs), are limited by issues such as systemic side effects, nonspecificity, and patient compliance challenges. Recently, hydrogel-based drug delivery systems have emerged as promising alternatives, providing localized, sustained, and stimuli-responsive therapeutic release. Hydrogels, with their high-water content and biocompatibility, enable the encapsulation and controlled delivery of various drugs including DMARDs, corticosteroids, and immunomodulatory agents. This review provides a comprehensive overview of recent advancements in hydrogel-based strategies for RA treatment, focusing on three key applications: (1) sustained DMARD delivery, (2) composite hydrogels integrating nanomaterials to impart additional disease-modifying properties such as targeted and controlled release of multiple drugs, including hydrophobic ones, and (3) hydrogel-mediated immunosuppressive cell delivery. By leveraging these multifunctional capabilities, hydrogels offer innovative solutions to overcome key challenges in conventional RA therapies. Although challenges in stability and scalability remain, ongoing advancements in hydrogel technology hold significant potential to transform RA management.