Pharmacology: Janus kinase-1 (JAK1)-selective inhibitor; JAK1 is essential for signaling for certain cytokines to elicit signals from various interleukins, cardiotrophin, neurotrophin, and interferons
These signals are essential in maintaining the inflammatory condition in rheumatoid arthritis (RA); inhibition of JAK reduces production of and modulates proinflammatory cytokines central to RA