The applied maximum dose of FLYSYN is by far lower than that of rituximab or obinutuzumab applied for B cell lymphoma especially in the maintenance therapy, which mirrors the by far higher expression of CD20 in lymphoma compared to FLT3 in AML in CR with MRD and the accordingly lower required drug level [11, 12, 40]. Here, FLT3 is linked to acute myeloid leukemia.