Baricitinib phosphate

Baricitinib phosphate (CAS 1187595-84-1), known as INCB028050, is an orally bioavailable small molecule inhibitor targeting Janus kinases JAK1 and JAK2. It selectively inhibits JAK1 and JAK2 with IC50 values of approximately 5.9 nM and 5.7 nM, respectively, exhibiting roughly 10-fold lower potency towards JAK3 and Tyk2, and lacking inhibition against c-Met and Chk2. By suppressing JAK1/2-mediated signaling, baricitinib phosphate reduces signal transduction induced by proinflammatory cytokines such as IL-6 and IL-23 in vitro. Preclinical studies in rodent arthritis models indicate notable therapeutic activity with minimal evidence of adverse hematological or immunosuppressive effects. This compound is used widely in biomedical research for investigating inflammatory pathways in autoimmune disease models.