CNX-500 is a probe consisting of a covalent Btk inhibitor (CC-292) chemically linked to biotin. CNX-500 retains inhibitory activity against Btk ( IC 50 of 0.5 nM) and the ability to form a covalent bond with Btk. CNX-500 has low inhibitory effects on kinase epidermal growth factor receptor, and upstream Src-family kinases including Syk and Lyn.
In Vitro
Used in a competition assay, CNX-500 detects free, uninhibited Btk and is excluded from interaction with Btk previously bonded by CC-292. In Ramos cells exposed to a range of CC-292 concentrations, the amount of Btk captured by the probe is compared with untreated samples and the extent of Btk bonded is demonstrated to be proportional to CC-292 drug concentration. MCE has not independently confirmed the accuracy of these methods. They are for reference only.