For example, midostaurin, an FLT3-inhibitor, has been approved by the FDA for treating AML, but it is a multi-kinase inhibitor that can interact with other kinases (PKC, VEGFR2, PDGFR-α/β, KIT, FGFR1), and it has not been specified whether it could be used in relapse and maintenance therapy or not. Here, FGFR1 is linked to acute myeloid leukemia.