Information RN486 RN486 is a potent and selective BTK inhibitor with IC50 of 4 nM. Targets BTK 4 nM In vitro RN486 not only potently and selectively inhibits the Btk enzyme, but also displays functional activities in human cell-based assays in multiple cell types, blocking Fcε receptor cross-linking-induced degranulation in mast cells (IC50 = 2.9 nM), Fcγ receptor engagement-mediated tumor necrosis factor α production in monocytes (IC50 = 7.0 nM), and B cell antigen receptor-induced expression of an activation marker, CD69, in B cells in whole blood (IC50 = 21.0 nM). RN486 is able to block the signaling of BCR as demonstrated by a marked inhibition of phosphorylation of both Btk and PLCγ2 in B cells. RN486 displays a selective B cell inhibitory profile in BioMAP Systems. In vivo RN486 displays similar functional activities in rodent models, effectively preventing type I and type III hypersensitivity responses. More importantly, RN486 produces robust anti-inflammatory and bone-protective effects in mouse CIA and rat adjuvant-induced arthritis (AIA) models. In the AIA model, RN486 inhibits both joint and systemic inflammation either alone or in combination with methotrexate, reducing both paw swelling and inflammatory markers in the blood.