ABSTRACT
İmatinib is a specific drug which was developed for the treatment of chronic myelogenous leukemia (KML) and is the pioneer drug in this area. İmatinib mesylate (Glivec) is a derivative of 2-phenylaminopyrimidine. It was approved by FDA for the treatment of KML in 2001. However, it was approved for the treatment of KML and gastrointestinal stromal tumors (GISTs) in 2003 in Turkey. İmatinib was developed as a specific inhibitor for tyrosine kinase in abl, c-kit and PDGF-R. Although imatinib has shown impressive effects in early phase KML, it is less effective in advanced phase KML because of resistance development. The mutations in bcr-abl kinase domain, seems to be the most important cause of resistance. Nowadays, many researches are studying to increase the therapeutic efficacy of imatinib and overcome its resistance because it seems to be a hopeful drug for the treatment of many diseases in the future.