Imatinib® (Imatinib)

Imatinib mesylate, a specific inhibitor of Bcr-Abl tyrosine kinase, is an antineoplastic agent that is structurally and pharmacologically distinct from other currently available antineoplastic agents.
The Philadelphia chromosome, characteristic of chronic myelogenous leukemia (CML), is created by a reciprocal translocation. Translocation between chromosomes results in production of an abnormal protein (Bcr-Abl tyrosine kinase) that exhibits enhanced tyrosine kinase activity.
Imatinib competitively inhibits Bcr-Abl tyrosine kinase, The drug has been shown to inhibit proliferation and induce apoptosis of Bcr-Abl positive cells as well as fresh leukemic cells from Philadelphia chromosome positive CML.

lmatinib also appears to inhibit receptor tyrosine kinases for platelet-derived growth factor (PDGF) and stem cell factor (SCF), c-Kit, and PDGF mediated and SCF-media cellular events. Data from in vitro studies shows that imatinib inhibits proliferation and induces apoptosis in gastrointestinal stromal tumor (GIST) cells.