ChEBI: Ibrutinib is a member of the class of acrylamides that is (3R)-3-[4-amino-3-(4-phenoxyphenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine in which the piperidine nitrogen is replaced by an acryloyl group. A selective and covalent inhibitor of the enzyme Bruton's tyrosine kinase, it is used for treatment of B-cell malignancies. It has a role as an EC 2.7.10.2 (non-specific protein-tyrosine kinase) inhibitor and an antineoplastic agent. It is a pyrazolopyrimidine, an aromatic amine, an aromatic ether, a member of acrylamides, a N-acylpiperidine and a tertiary carboxamide.NCI Thesaurus (NCIt): Ibrutinib is an orally bioavailable, small-molecule inhibitor of Bruton's tyrosine kinase (BTK) with potential antineoplastic activity. Upon oral administration, ibrutinib binds to and irreversibly inhibits BTK activity, thereby preventing both B-cell activation and B-cell-mediated signaling. This leads to an inhibition of the growth of malignant B cells that overexpress BTK. BTK, a member of the src-related BTK/Tec family of cytoplasmic tyrosine kinases, is required for B cell receptor signaling, plays a key role in B-cell maturation, and is overexpressed in a number of B-cell malignancies. The expression of BTK in tumor cells is also associated with increased proliferation and survival.