CTA101 UCAR-T Cell Injection for Treatment of Relapsed or Refractory CD19+ B-cell Acute Lymphoblastic Leukemia

Inclusion Criteria: 1. Male or female aged 3-70 years old; 2. Histologically confirmed diagnosis of CD19+ B-ALL per the US National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines for Acute Lymphoblastic Leukemia (2016.v1); 3. Relapsed or refractory CD19+ B-ALL (meeting one of the following conditions): 1. CR not achieved after standardized chemotherapy; 2. CR achieved following the first induction, but CR duration is ≤ 12 months; 3. Ineffectively after first or multiple remedial treatments; 4. 2 or more recurrences; 4. The number of primordial cells (lymphoblast and prolymphocyte) in bone marrow is﹥5%; 5. Philadelphia-chromosome-negative (Ph-) patients; or Philadelphia-chromosome-positive (Ph+) patients who cannot tolerate TKI treatments or do not respond to 2 TKI treatments; 6. Serum albumin ≥ 30g/L, total bilirubin ≤ 25.7umol/L, ALT and AST ≤ 3 times of upper limit of normal, creatinine ≤ 176.8umol/L, platelet count ≥ 50\*10\^9/L; 7. Echocardiogram (ECHO) shows left ventricular ejection fraction (LVEF) ≥ 50%; 8. No active infection in the lungs, blood oxygen saturation in indoor air is ≥ 92%; 9. Latest treatment (radiotherapy, chemotherapy, monoclonal antibody therapy or other treatment) must have been completed at least 2 weeks prior to screening; 10. Estimated survival time ≥ 3 months; 11. ECOG performance status 0 to 1; 12. Patients or their legal guardians volunteer to participate in the study and sign the informed consent. Exclusion Criteria: 1. History of hypersensitivity to any component of cell product; 2. Prior treatment with any CAR T cell product or other genetically-modified T cell therapies; 3. Patients with extramedullary lesions; 4. Confirmed diagnosis of lymphoblastic crisis of chronic myeloid leukemia, Burkitt's leukemia/ lymphoma per WHO Classification Criteria; 5. Patients with hereditary syndrome such as Fanconi anemia, Kostmann syndrome, Shwachman syndrome or any other known bone marrow failure syndrome; 6. Patients with New York Heart Associate (NYHA) Class III/IV cardiac insufficiency; 7. Myocardial infarction, cardioangioplasty or stenting, unstable angina pectoris, or other severe cardiac diseases within 12 months of enrollment; 8. Severe primary or secondary hypertension of grade 3 or above (WHO Hypertension Guidelines, 1999); 9. History of craniocerebral trauma, conscious disturbance, epilepsy, cerebrovascular ischemia, and cerebrovascular hemorrhagic diseases; 10. Central nervous system leukemia (CNS2 or CNS3), resistant to intrathecal injecting of chemotherapeutic drugs, and/or undergoing skull and/or spine radiotherapy; patients with history of CNS but effectively controlled to allow enrollment; 11. Prior treatment with TKIs (Ph+ ALL) 1 week prior to enrollment; 12. Patients with severe active infections (excluding simple urinary tract infection and bacterial pharyngitis), or currently receiving antibiotic therapy by intravenous infusion, or have received antibiotic treatment by intravenous infusion within 1 week before cell infusion. However, prophylactic antibiotic, antiviral and antifungal treatments are allowed; 13. Indwelling catheters in vivo (e.g. percutaneous nephrostomy, Foley catheter, bile duct catheter, or pleural/peritoneal/pericardial catheter). Ommaya storage, dedicated central venous access catheters such as Port-a-Cath or Hickman catheters are allowed; 14. History of other primary cancer, except for the following conditions: 1. Cured non-melanoma after resection, such as basal cell carcinoma of the skin; 2. Cervical cancer in situ, localized prostate cancer, ductal cancer in situ with disease-free survival ≥ 2 years after adequate treatment; 15. Patients with autoimmune diseases requiring treatment, patients with immunodeficiency or requiring immunosuppressive therapy; 16. Patients with graft-versus-host disease (GVHD); 17. If HBsAg positive at screening, HBV DNA copy number detected by PCR in patients with active hepatitis B \> 1000 (if HBV DNA copy number≤1000, routine antiviral therapy is required after enrollment), as well as CMV, hepatitis C, syphilis and HIV infection; 18. Concurrent therapy with systemic steroids within 1 week prior to screening, except for the patients recently or currently receiving inhaled steroids; 19. Women pregnant or lactating, with a pregnancy plan within 6 months, fertile but unable to take medically acceptable contraception measures.