Discussion
AML
DISEASE, AML, COMPLICATION, HEMATOLOGIC MALIGNANCIES
This dose-escalation study demonstrates that the Fc-optimized FLT3 antibody FLYSYN applied as monotherapy is very well-tolerated and shows promising clinical activity in terms of achieving MRD reduction or even MRD negativity in AML patients.Tolerability and safety of FLYSYN was equally distributed over the various dose levels, with a tendency to more AEs at doses > 15 mg/mA major complication of mAb treatment is the development of ADAs, which may neutralize the therapeutic mAb upon repetitive dosing and thus limit efficacy [Molecular response to treatment, defined as ≥ 1 log MRD reduction or negativity in BM, was achieved in 35% of patients, of which two maintained documented MRD negativity at last study visit. Even if efficacy was not the primary endpoint and these findings require further evaluation in consecutive trials, our results are promising, as MRD is associated with disease outcome in AML and also other hematologic malignancies [Together, the favorable safety and preliminary efficacy data confirm the suitability of FLT3 as target antigen for immunotherapy in AML. Notably, activating mutations occurring in the 