The PK profile of midostaurin, characterized in these and other studies, supports its further evaluation in patients with ASM and AML, including the ongoing global phase II study of midostaurin in patients with ASM or mast cell leukemia with or without an associated clonal hematologic non-mast cell lineage disease [16], and the ongoing randomized phase III trial of induction and consolidation chemotherapy with midostaurin or placebo in treatment-naive patients with FLT3-mutated AML [Cancer and Leukemia Group B 10603; Randomized AML Trial in FLT3 in <60-year-olds (RATIFY)] [12]. Here, FLT3 is linked to mast cell leukemia.