CD19 CAR-T Cell Infusion as Consolidation Therapy in Adolescent and Adult Patients With Acute B-ALL Ineligible for Allogeneic HSCT: A Clinical Study

Prior treatment

• Prior treatment with CAR-T cell therapy before screening or conditioning.
• History of deep vein thrombosis or pulmonary embolism within six months before screening.
• Live vaccine administration within six weeks before screening.
• Participation in other interventional clinical trials and receipt of an investigational agent, including:
  • An unapproved investigational drug within three months before cell infusion. A marketed drug within fewer than five half-lives before cell infusion.

Other illness

• Patients with bone marrow failure syndromes associated with genetic disorders, such as Fanconi anemia, Kostmann syndrome, Shwachman syndrome, or any other known bone marrow failure syndromes.
• Any of the following viral infections:
  • Hepatitis B virus (HBV) DNA detectable above the lower limit of quantification. Positive hepatitis C virus antibody (HCV-Ab). Epstein-Barr virus (EBV) or cytomegalovirus (CMV) DNA detectable above the lower limit of quantification.
  • Positive human immunodeficiency virus (HIV) antibody test.
• History of or current malignancy within the past five years (excluding patients with a low risk of recurrence after curative treatment and more than five years of follow-up, as determined by the investigator).
• Uncontrolled epilepsy, a history of cerebrovascular ischemia/hemorrhage, cerebellar disease, or other active central nervous system (CNS) disorders.
• Known hypersensitivity to any component of the study treatment.
• Severe, uncontrolled, active infection at screening.
• Any other conditions deemed unsuitable for study participation by the investigator.
• Physical or cognitive conditions that impair the ability to provide informed consent or comply with study procedures, or unwillingness or inability to adhere to study requirements.

Lab values

• Any of the following cardiac conditions:
  • New York Heart Association (NYHA) Class III or IV congestive heart failure. Severe arrhythmia requiring treatment or clinically significant conduction abnormalities on ECG, including QTc interval ≥480 ms (QTcB = QT/√RR).
  • Uncontrolled hypertension despite standard treatment (systolic blood pressure ≥150 mmHg and/or diastolic blood pressure ≥100 mmHg) or pulmonary hypertension.
  • Unstable angina. Myocardial infarction, coronary artery bypass grafting, or stent placement within six months before cell infusion.
  • Clinically significant valvular heart disease. Other cardiac diseases deemed inappropriate for study participation by the investigator.

Other

• Presence of mixed-lineage leukemia or biphenotypic leukemia.
• Clinically significant pericardial or pleural effusion at screening.

• The subject has voluntarily agreed to participate, signed the informed consent form, and is willing and able to comply with scheduled visits, study treatment, laboratory tests, and other study procedures.
• The subject has been clinically diagnosed with newly diagnosed or refractory/relapsed B-cell acute lymphoblastic leukemia (B-ALL), including Burkitt lymphoma leukemia and blast-phase chronic myeloid leukemia, and has achieved complete remission (defined as \<5% bone marrow blasts, no peripheral blood blasts, and no extramedullary leukemia) after chemotherapy or immunotherapy, but is either ineligible for allogeneic hematopoietic stem cell transplantation (allo-HSCT), lacks a suitable donor, or declines transplantation.
• Aged between 14 and 80 years (inclusive), male or female.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2.
• At the time of screening, leukemia cells in the bone marrow or peripheral blood must be confirmed as CD19-positive by flow cytometry at initial or relapse diagnosis.
• An expected survival of more than three months from the date of signing the informed consent form.
• Satisfactory liver, kidney, cardiac, and pulmonary function, defined as:
  • Creatinine ≤2× upper limit of normal (ULN);
  • Left ventricular ejection fraction (LVEF) ≥50%;
  • Blood oxygen saturation \>92%;
  • Total bilirubin ≤2× ULN; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤3× ULN.
• Adequate venous access for cell collection and meeting the following hematologic criteria:
  • Hemoglobin ≥80 g/L Absolute neutrophil count (ANC) ≥1.0 × 10⁹/L Platelet count ≥75 × 10⁹/L If the above criteria are not met, the investigator may determine eligibility for mononuclear cell collection.
• Female subjects of childbearing potential must have a negative serum pregnancy test (women who have undergone surgical sterilization or have been postmenopausal for at least two years are considered non-fertile). Male and female subjects of reproductive potential must agree to use contraception during the study.