STI571, a tyrosine kinase inhibitor for the treatment of chronic myelogenous leukemia: Validating the promise of molecularly targeted therapy

The deregulated tyrosine kinase activity of the Bcr-Abl fusion protein has been established as the causative molecular event in chronic myelogenous leukemia (CML). Thus the Bcr-Abl tyrosine kinase is an ideal target for pharmacologic inhibition. STI571 (formerly CGP57148B), is an Abl-specific tyrosine kinase inhibitor that in preclinical studies selectively kills Bcr-Abl-containing cells in vitro and in vivo. The results of clinical studies have demonstrated the potential of molecularly targeted therapies, and STI571 is emerging as a new therapeutic agent for CML.