Tofacitinib for the treatment of moderate to severe rheumatoid arthritis.

The autoimmune disease rheumatoid arthritis (RA) causes severe disability through chronic and destructive inflammation of the synovial joints. Currently available therapeutic options, including disease-modifying antirheumatic drugs (DMARDs) and biologic agents, often fail to adequately prevent disease progression. Tofacitinib (CP-690550) is an inhibitor of the Janus kinase family; tyrosine kinase receptors expressed in lymphoid cells that are involved in the signaling of cytokines important for the production and function of various immune cells implicated in RA pathogenesis. Tofacitinib has been evaluated in phase II, phase III and long-term extension studies, as both monotherapy and in combination with methotrexate and other DMARDs, and demonstrates statistically significant and clinically meaningful improvements in the signs and symptoms of RA, patient health, physical functioning and quality of life, while having a manageable safety profile. It is currently under evaluation for approval for the treatment of adults with RA by several regulatory agencies around the world.