Imatinib (INN), marketed by Novartis as Gleevec (U.S.) or Glivec (Europe/Australia/Latin America) & markered by Natco as Veenat (India), and sometimes referred to by its investigational name STI-571, is a tyrosine-kinase inhibitor used in the treatment of multiple cancers, most notably Philadelphia chromosome-positive (Ph+) chronic myelogenous leukemia (CML). Like all tyrosine-kinase inhibitors, imatinib works by preventing a tyrosine kinase enzyme, in this case BCR-Abl, from phosphorylating subsequent proteins and initiating the signaling cascade necessary for cancer development, thus preventing the growth of cancer cells and leading to their death by apoptosis. Because the BCR-Abl tyrosine kinase enzyme exists only in cancer cells and not in healthy cells, imatinib works as a form of targeted therapy—only cancer cells are killed through the drug’s action. In this regard, imatinib was one of the first cancer therapies to show the potential for such targeted action, and is often cited as a paradigm for research in cancer therapeutics.
Imatinib has been cited as the first of the exceptionally expensive cancer drugs, costing $92,000 a year. Doctors and patients complain that this is excessive, given that its development costs have been recovered many times over, and that the costs of synthesizing the drug are orders of magnitude lower. In the USA, the patent protecting the active principal will expire on 4 January 2015 while the patent protecting the beta crystal form of the active principal ingredient will expire on 23 May 2019.
The developers of imatinib were awarded the Lasker Award in 2009 and the Japan Prize in 2012.