Both bosutinib and dasatinib inhibit the kinase activity of the BCR-Abl fusion, as well as Src and BTK (Fig. 7b), and are used to treat Philadelphia chromosome- positive (Ph+) chronic myelogenous leukaemia (CML) and acute lymphoblastic leukaemia (ALL)47,48. Here, BTK is linked to chronic myelogenous leukemia, BCR-ABL1 positive.