Imatinib, the first generation of tyrosine kinase inhibitor, is a milestone drug in the history of treating chronic myeloid leukemia (CML). It was launched by Novartis in 2001 and is a model of successful targeted therapy Chemicalbook. It only kills BCR-ABL contained in myeloid cells, prevents cell proliferation and tumor formation, but has no effect on normal cells. It can also inhibit PDGF-mediated tumors, including glioma and prostate cancer.