The international phase II clinical study of dasatinib and nilotinib, second-generation cancer-targeting therapies, in imatinib failed patients which began in 2005 showed that more than 70 percent of the patients achieved a complete hematological response (CHR) again, and about 50 percent of the patients, a major hematological response (MHR). In the study, it was also observed that kinase activation was inhibited by a second-generation cancer-targeting therapy for most of the major imatinib-resistant point mutations. With regard to peculiar point mutations, V299L, F317L, and E25K/V show relative resistance to dasatinib, and p-loop mutations including G250E, Q252H, Y253F/H and E255K/V and F359C/V show relative resistance to nilotinib. T315I mutation exhibits strong resistance to both of these cancer-targeting therapies. Therefore, it is considered that the second-generation cancer-targeting therapies show therapeutic effects in different domains.