Consistent with the data showing pacritinib blocks FLT3 activity in vitro, in preclinical studies, pacritinib treatment of AML cells blocks FLT3 autophosphorylation as well as signaling pathways downstream of FLT3 including mitogen-activated protein kinase (MAPK) and PI3K signaling30,31. Here, FLT3 is linked to acute myeloid leukemia.