Designing micro- and nano-particles for treating rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic, destructive autoimmune disease that can cause disability and have a negative socioeconomic impact. Despite significant advances in therapeutic options, limitations on the routes of administration and the requirement for frequent and long-term dosing often lead to systemic adverse effects and patient non-compliance. Micro and nanoparticle systems that selectively deliver drugs to inflamed synovium have the potential to improve drug efficacy while leaving extrasynovial tissues unaffected. This review summarizes key design parameters of RA-targeted drug carriers and discusses design considerations for improving RA therapies.