Background:

PCI 29732 is a selective and irreversible Btk inhibitor with IC50 of 8.2 nM in a FRET based biochemical enzymology assay.IC50 value: 8.2 nM [1]Target: Btk kinasePCI 29732(compound 1) has a 8.2 nM potency against Btk in a FRET based biochemical enzymology assay. PCI 29732 shows only modest inhibitory activity against Itk, another Tec family kinase, probably due to the difference at the "gatekeeper" residue [1].In human CD20+ B cells stimulated at the BCR, PCI-29732 blocked the transcriptional up-regulation of a panel of B-cell activation genes that occurs within 6 h of stimulation. Pulse exposure to the reversible inhibitor PCI-29732 did not result in BCR inhibition [2].

[1]. Pan Z, et al. Discovery of selective irreversible inhibitors for Bruton’s tyrosine kinase. ChemMedChem. 2007 Jan;2(1):58-61. [2]. Honigberg LA, et al. The Bruton tyrosine kinase inhibitor PCI-32765 blocks B-cell activation and is efficacious in models of autoimmune disease and B-cell malignancy. Proc Natl Acad Sci U S A. 2010 Jul 20;107(29):13075-80.