FLT-3 is expressed on committed lymphoid and myeloid progenitors and on monocytes.70, 71 Activating FLT-3 mutations are present in about 30% of patients with AML.72 Furthermore, the level of FLT-3 expression on AML cells is increased and is associated with higher percentage of bone marrow blasts and high leukocyte counts.70, 73 Two bispecific antibody formats have been designed to redirect T cells towards FLT-3(+)AML cells. Here, FLT3 is linked to acute myeloid leukemia.