Description: Ibrutinib (formerly PCI32765; trade name Imbruvica), an approved anticancer drug, is a covalent/irreversible and orally bioavailable Brutons tyrosine kinase (Btk) inhibitor with potential anti-cancer activity. It inhibits BTK with an IC50 of 0.5 nM in cell-free assays, and exhibits modest potency against other kinases such as Bmx, CSK, FGR, BRK, HCK, less potent to EGFR, Yes, ErbB2, JAK3, etc. on November 13th 2013, Ibrutinib was approved by the US FDA for the treatment of mantle cell lymphoma.