New Drug Approvals 2013 - Pt. XIX - Ibrutinib (ImbruvicaTM)
On November 13, 2013, the FDA approved Ibrutinib (ImbruvicaTM) for the treatment of patients with mantle cell lymphoma (MCL) who have received at least one prior therapy. MCL is a subtype of B-cell lymphoma and accounts for 6% of non-Hodgkin's lymphoma cases. In an open-label, multi-center, single-arm trial of 111 previously treated patients, Ibrutinib showed a 65.8% response rate.
Ibrutinib is an irreversible inhibitor of the Tyrosine-protein kinase BTK (Uniprot:Q06187; ChEMBL:CHEMBL5251; canSAR target synopsis) and is the first approved targeted BTK inhibitor. It forms a covalent bond with a cysteine residue via a Michael acceptor mechanism, in the BTK active site, leading to inhibition of BTK enzymatic activity
Ibrutinib (ChEMBL:CHEMBL1873475; canSAR drug synopsis; also known as CRA-032765 and PCI-32765) has the formula C25H24N6O2 and a molecular weight 440.50. It is absorbed after oral administration with a median Tmax of 1-2 hours. After administration of 560 mg dose, the observed AUC is 953 ± 705 ng⋅h/mL. The apparent volume of distribution at steady state (Vd,ss/F) is approximately 10000 L and the half-life is 4 to 6 hours.
ImbruvicaTM is produced by Pharmacyclics, Inc.
The full Prescribing Information is here