Acute myeloid leukemia (AML) is a hematological malignancy characterized by clonal proliferation of hematopoietic stem cells or progenitor cells. AML is the most common type of leukemia in adults; the 5-year survival rate is only 24%. Moreover, 40%-50% of young patients and most elderly patients eventually suffered relapses.~FMS-like tyrosine kinase 3 (FLT3) is a member of the class III receptor tyrosine kinases, mainly expressed on the cell surface of hematopoietic progenitor cells and plays an important role in normal hematopoiesis such as proliferation, differentiation and survival. The variable expression of FLT3 can be found on leukemia blasts from over 90% of AML patients. Although about 30% of AML have FLT3 gene mutations, the ectodomain of the FLT3 molecule is usually spared so that cellular immunotherapy against it has great therapeutic potential. It is shown that FLT3 expression is detected in more than half of hematopoietic stem cell (HSC) and multipotent progenitor (MPP) cells on average, while the average positive rate of lymphoid progenitor (CLP) cells is less than 20%. Since the expression level of FLT3 on hematopoietic cells is not as high as CD33 and CD123, potential hematological toxicity has been supposed to be less obstructive to the development of FLT3-CAR-T Cell products. Besides, the expression of FLT3 is not found in other normal tissues. And it is reported that FLT3 CAR T cells did not deplete CD34(+) HSCs and preserve HSC differentiation in the mice model. Therefore, conducting CAR-T cell therapy targeting the FLT3 molecule could be very promising in the clinical practice of treating AML. TAA05 Cell Injection is a kind of FLT3-targeted CAR-T cell containing an optimized CD28 costimulatory domain which could help reduce the risk of toxic side effects. This clinical trial aims to evaluate the safety and efficacy of TAA05 Cell Injection in patients with FLT3 positive AML.
This is a clinical trial of Anti-FLT3 CAR-T Cell (TAA05 Cell Injection) in the treatment of patients with relapsed / refractory acute myeloid leukemia. The purpose is to evaluate the safety and efficacy of anti-FLT3 CAR-T cells in patients with relapsed / refractory acute myeloid leukemia.