Safety and Efficacy of Anti-CD123 CAR-T Therapy in Patients With Refractory/ Relapsed CD123+ Acute Myeloid Leukemia.

Inclusion Criteria:

1. Pathological and histological examination confirmed CD123+ refractory or relapsedAcute Myeloid Leukemia. A. Diagnostic criteria for recurrent AML: After complete remission (CR), leukemiacells or bone marrow primordial cells > 0.050 (except for bone marrow regenerationafter consolidation chemotherapy) or extramedullary leukemia cell infiltration appearsagain in peripheral blood. B．Diagnostic criteria for refractory AML(Meeting one of the following) i. ineffectiveness after the first standard regimen treatment of 2 courses. ii. patients relapse within 12 months after consolidation and intensive treatmentafter CR. iii. Patients relapse 12 months later and fail to respond to conventionalchemotherapy. iv. Patients with two or more recurrences. v. Patients with persistent extramedullary leukemia. vi. Patients with recurrence after CR and unsuitable for HSCT (auto/allo-HSCT).

2. Aged 18 to 70 years (including 18 and 70 years old).

3. At least one measurable or evaluable lesion：AML patients with positive or relapsedpositive bone marrow MRD.

4. ECOG≤ 2 and expected lifetime ≥3 months.

5. Adequate organ function: A. Liver function: ALT/AST≤3 ULN. Total bilirubin≤2 ULN. B. Renal function: eGFR> 60 mL/min/1.73 m2, or creatinine clearance ≥45mL/min. C. Lung function: Carbon Monoxide (DLCO) or Forced Expiratory Volume in the firstsecond (FEV1) > 45% predicted. D. Cardiac function: LVEF ≥ 50%.

6. The patients did not receive any anticancer treatments such as chemotherapy,radiotherapy and immunotherapy (such as immunosuppressive drugs) within 4 weeks beforeadmission, and the toxicity related to previous treatments had returned to < 1 levelat admission (except for low toxicity such as alopecia).

7. Women of child-bearing potential and all male participants must use effective methodsof contraception for at least 12 months after infusion.

8. Informed Consent/Assent: All subjects must have the ability to understand and thewillingness to sign a written informed consent.

Exclusion Criteria:

1. Women who are pregnant (urine/blood pregnancy test positive) or lactating.

2. Male or female with a conception plan in the past 1 years.

3. Patients cannot guarantee effective contraception (condom or contraceptives, etc.)within 1 years after enrollment.

4. Uncontrolled infectious disease within 4 weeks prior to enrollment.

5. Active hepatitis B/C virus.

6. HIV infected patients.

7. Suffering from a serious autoimmune disease or immunodeficiency disease.

8. The patient is allergic and is allergic to macromolecular biopharmaceuticals such asantibodies or cytokines.

9. The patient participated in other clinical trials within 6 weeks prior to enrollment.

10. Systemic use of hormones within 4 weeks prior to enrollment (except for patients withinhaled corticosteroids).

11. Suffering from mental illness.

12. Patient has drug abuse/addiction.

13. Central nervous system involvement.

14. According to the investigator's judgment, the patient has other unsuitable groupingconditions.