Signal transduction inhibitors (STI571): molecularly targeted therapy

The therapy of chronic myeloid leukemia (CML), characterized by the presence of the Philadelphia chromosome in the clonal hematopoietic stem cells, has changed dramatically in the last year with the development of a specific inhibitor of the BCR-ABL tyrosine kinase. This medication, STI571 or imatinib, was recently approved by the Food and Drug Administration for CML patients refractory or intolerant to interferon. The medication has the potential to rapidly reverse the clinical and hematologic abnormalities of CML and is the paradigm of molecularly targeted therapy. STI571 is the first agent in Oncology that directly targets the molecular basis of a malignant disease, changing the way that we will treat these conditions in the future. This new field of molecular and cellular biology has the possibility of controlling not only malignant conditions but also diseases treated by other medical specialties.