Gleevec/Low-Dose Ara-C Study for Elderly Patients With AML and Myelodysplastic Syndromes

Imatinib mesylate is a drug that blocks a certain protein. This protein is thought to be important in the growth of leukemia cells. Ara-C is a chemotherapy drug that has been used for many years to treat AML and MDS. Imatinib mesylate (Gleevec) is a protein-tyrosine kinase inhibitor that inhibits the Bcr-Abl tyrosine kinase, as well as the receptor tyrosine kinases for platelet- derived growth factor (PDGF) and stem cell factor (SCF), c-Kit, and inhibits PDGF- and SCF-mediated cellular events. c-Kit is expressed in over 90% of patients with AML. The treatment of AML for patients age 65 or older with AML or high-risk MDS (age ³ 60 if high-risk cytogenetics) have a poor prognosis with induction chemotherapy. Response rate is no more than 45% with an induction mortality of at least 25%, and 1-year survival no better than 20%. Indeed, most patients in these age groups are not even offered therapy and are managed with supportive care only. Thus, new therapies that are better tolerated are needed. Imatinib alone can induce response in nearly 20% of patients, and there is synergy with low concentrations of ara-C. In this study we plan to investigate the combination of imatinib and low-dose ara-C.