A novel pyrido[2,3-d]pyrimidine derivative, PD-180970, has been shown to potently inhibit Bcr-Abl and induce apoptosis in Bcr-Abl-expressing leukemic cells. PD-180970 is active against several Bcr-Abl mutations that are resistant to imatinib and support the notion that developing additional Abl kinase inhibitors would be useful as a treatment strategy for chronic myelogenous leukemia. PD-180970 is also an inhibitor of Src, and KIT.