MB-CART19.1 in Relapsed/Refractory Acute Lymphoblastic Leukemia

Inclusion Criteria:

* Age ≥ 1 year as long as if deemed fit by treating investigator
* CD19 expression must be detected (≥20%) on the malignant cells by flow cytometry.
* Patients with relapsed or refractory disease with 0.01% or higher blasts in the bone marrow, or patients with confirmed disease progression as demonstrated by FDG PET-CT or CT/MRI of the affected lymph node or spleen after at least 2 cycles/lines of chemotherapy are eligible for enrollment. For patients with Philadelphia-positive disease, a second-generation or higher TKI must have been utilized in one of the treatment lines.
* Patients who have relapsed post alloSCT at least 100 days post-transplant, with no evidence of active graft vs host disease, and no longer taking immunosuppressive agents for at least 30 days prior to enrollment.
* Estimated life expectancy \> 12 weeks
* Karnofsky or Lansky (age dependent) performance score ≥ 60
* Patients and/or parents must give their written informed consent/assent.
* CNS and/or testicular involvement are allowed, only if cleared and in the presence of systemic involvement.

Exclusion Criteria:

* Rapidly progressive, uncontrolled disease as assessed by the treating physician and/or principal investigator.
* Persistent extramedullary disease.
* Isolated CNS and/or testicular disease.
* Current autoimmune disease, or history of autoimmune disease with potential CNS involvement
* Active hepatitis B, C or HIV
* Active clinically significant CNS dysfunction (including but not limited to uncontrolled seizure disorders, cerebrovascular ischemia or hemorrhage, dementia, paralysis)
* History of an additional malignancy (≤ 3 years) other than non-melanoma skin cancer or carcinoma in situ.
* Pulmonary function: Patients with pre-existing severe lung disease (FEV1 or FVC \< 65%) or an oxygen requirement of \>28% O2 FiO2 or active pulmonary infection.
* Cardiac function: Left ventricular ejection fraction \<50% by echocardiography
* Renal function: Creatinine clearance \<50 mL/min/1.73 m2
* Liver function: patients with serum bilirubin ≥3 times upper limit of or AST or ALT \> 5 times upper limit of normal, unless due to leukemic liver infiltration as determined by the investigators.
* Pregnant or breast-feeding females
* Medications: systemic chemotherapies, corticosteroids with the exception of physiologic replacement dosing (\<0.5 mg/kg/day of methylprednicone), tyrosine kinase inhibitors (TKI) within 7 days prior to leukapheresis, Fludarabine/clofarabine or immunosuppressive drugs and antibodies (e.g. rituximab, blinatumomab) or investigational drugs or donor lymphocyte