Treatment for MRD-Positive B-ALL Patients Using CAR-T Therapy

Inclusion Criteria:

* Age between ≥16 and ≤70 years at screening, no gender restrictions
* ECOG score of 0-1 at screening
* Newly diagnosed Ph-negative B-ALL, MRD positive(bone marrow MRD ≥0.01% by flow cytometry) in CR1 (with \<5% blasts in bone marrow, no blasts in peripheral blood, no extramedullary disease)after induction chemotherapy or consolidation chemotherapy.
* Newly diagnosed Ph-positive B-ALL, MRD positive(bone marrow MRD ≥0.01% by flow cytometry or BCR-ABL1 \>0.01% detected by qPCR) in CR1 (with \<5% blasts in bone marrow, no blasts in peripheral blood, no extramedullary disease) .
* At diagnosis of B-ALL,CD19 expression of leukemic cells is positive by flow cytometry in bone marrow or peripheral blood.
* Appropirate organ function, meeting the following criteria:

  1. Aspartate aminotransferase (AST) ≤3 times the upper limit of normal (ULN);
  2. Alanine aminotransferase (ALT) ≤3 times ULN;
  3. Total bilirubin ≤2 times ULN (for patients with Gilbert's syndrome, total bilirubin ≤3.0 times ULN and direct bilirubin ≤1.5 times ULN);
  4. Serum creatinine ≤1.5 times ULN, or creatinine clearance ≥60 mL/min (using the Cockcroft-Gault formula);
  5. International Normalized Ratio (INR) ≤1.5 times ULN and activated partial thromboplastin time (APTT) ≤1.5 times ULN;
  6. Left ventricular ejection fraction (LVEF) ≥50%;
  7. Minimum pulmonary reserve, with oxygen saturation \>91% on room air;
* Meets leukapheresis standard of the study center, with no contraindications for blood cell separation;
* Voluntarily agrees to participate in this study and signs on the informed consent form(ICF).

Exclusion Criteria:

* Received CAR-T cell therapy before screening;
* Inherited bone marrow failure syndrome(IBMFS) or any other known bone marrow failure syndromes;
* Active systemic autoimmune diseases requiring treatment;
* Any of the following conditions:

  1. HBsAg and/or HBeAg positive;
  2. HBe-Ab and/or HBc-Ab positive with HBV-DNA levels above the lower limit of quantification;
  3. HCV-Ab positive;
  4. TP-Ab positive;
  5. HIV antibody positive;
  6. EBV-DNA or CMV-DNA levels above the lower limit of quantification;
* Active infection at screening.
* Any other malignancy within the past five years before screening, excluding cases where the patient has been disease-free for more than 5 years after curative treatment or has a low risk of relapse as assessed by the investigator;
* Any of the following cardiac conditions:

  1. NYHA Class III or IV congestive heart failure;
  2. Severe arrhythmia requiring treatment;
  3. Uncontrolled hypertension or pulmonary hypertension despite standard therapy;
  4. Unstable angina;
  5. Myocardial infarction, bypass surgery, or stent placement within six months before cell retransfusion;
  6. Clinically significant valvular disease;
  7. Other cardiac conditions deemed unsuitable by the investigator;
* History of epilepsy, cerebellar disease, or other active central nervous system disorders;
* Uncontrolled diabetes;
* History of symptomatic deep vein thrombosis or pulmonary embolism within six months before screening that is not well controlled;
* History of hypersensitivity to any component of the investigational product.
* Received a live vaccine within six weeks before screening;
* Life expectancy of less than three months;
* Participation in another interventional clinical trial and receiving investigational drugs within three months (for unapproved drugs) or within five half-lives (for approved drugs) before cell infusion, or plans to participate in another clinical trial or receive anti-cancer therapy outside the study protocol during the study period;
* Other conditions deemed unsuitable for participation in this clinical trial by the investigator.