PT - JOURNAL ARTICLE AU - Lederman, Lynne ED - O'Shea, John J. TI - Development, Safety, and Efficacy of Janus Kinase Inhibitors in Rheumatoid Arthritis DP - 2013 Feb 01 TA - MD Conference Express PG - 31--32 VI - 13 IP - 18 4099 - http://mdc.sagepub.com/content/13/18/31.short 4100 - http://mdc.sagepub.com/content/13/18/31.full AB - The four Janus kinases (JAKs), JAK1, JAK2, JAK3, and Tyk2, are essential components of the signaling pathway of certain cytokines [O'Shea JJ et al. N Engl J Med 2013]. This article reviews the role of JAKs in inflammation and JAK inhibitor efficacy and toxicity, the clinical data for tofacitinib, as well as discusses kinase inhibition in development, baricitinib, which strongly inhibits JAK1 and JAK2.