A Clinical Study Exploring Universal CAR-T Cell in Patients With Relapsed/Refractory B-cell Acute Lymphoblastic Leukemia

1. Participants must voluntarily sign the informed consent form (ICF) and must be willing and be able to adhere to the study visit schedule and other protocol requirements
2. 18-75 years old;
3. Histologically or cytologically confirmed B-ALL;
4. Previously received at least 2 lines of systemic therapy;
5. Expected survival > 12 weeks;
6. Eastern Cooperative Oncology Group (ECOG) score 0-2;
7. Female participants of childbearing potential must have a negative pregnancy test at screening and prior to receiving preconditioning therapy。Both male and Female are willing to use a highly effective and reliable method of contraception for 1 year after receiving study treatment and are absolutely prohibited from donating sperm donation or eggs for 1 year after receiving study treatment infusion during the study.

Exclusion Criteria:

1. Pregnant or lactating women;
2. Has HIV, syphilis infection, active hepatitis B virus infection (HBsAg positive and HBV-DNA above the detection limit), or active hepatitis Cvirus infection (HCV antibody and HCV-DNA positive);
3. Has any current uncontrolled active infection, including but not limited to participants with active tuberculosis (investigator 's judgment);
4. Participants' toxicities caused by previous treatment did not recover to Common Terminology Criteria for Adverse Events (CTCAE) ≤ Grade1, except alopecia and other events that are judged tolerable by the investigator;
5. Patients with isolated extramedullary lesions;
6. Vaccination with live attenuated vaccines, inactivate vaccines or RNA vaccines within 4 weeks prior to informed consent;
7. Participants who are allergic or intolerant to preconditioning drugs, tocilizumab, or have other previous history of severe allergy such as anaphylactic shock;
8. Patients with heart disease in the 6 months prior to screening;
9. Presence of a second primary malignancy requiring treatment or not in complete remission within the past 2 years;
10. Serious pulmonary diseases that are judged by the investigator to potentially endanger the patient's life when participating in the study.