Although early preclinical studies suggested that midostaurin might be useful in a wide variety of TK-driven malignant diseases including solid tumors and haematological neoplasms (Monnerat, 2004; Millward et al., 2006), a relevant clinical efficacy has only been demonstrated in FLT3-positive acute myeloid leukemia (AML) and AdvSM, which actually constitute the only two indications of midostaurin approved by the U.S. FDA and the EMA. The gene discussed is FLT3; the disease is acute myeloid leukemia.