This study seeks to examine the efficacy and safety of the administration of autologous T cells that have been modified through the introduction of a chimeric antigen receptor (CAR) targeting the B cell surface antigen CD19 following administration of chemotherapy lymphodepletion regimen in children with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoma. The overall goal of this study is to validate the safety profile of administration CD19-CAR T cells and describe the response rate in children with relapsed/refractory ALL or lymphoma.

Inclusion Criteria:

• Subjects must have relapsed or refractory ALL or lymphoma treated with at least two lines of therapy. Disease must have either progressed after the last regimen or presented failure to achieve partial or complete remission with the last regimen.

• The patient's disease must be CD19 positive, either by immunohistochemistry or flow cytometry analysis on the last biopsy available.

• Age 1-17 years.

• Performance status: Subjects > 10 years of age: Karnofsky ≥ 50%; Subjects ≤ 10 years of age: Lansky scale ≥ 50%.

• Normal organ function.

  • Total bilirubin ≤ 3 times upper limit of normal
  • AST (SGOT) ≤ 5 times upper limit of normal
  • ALT (SGPT) ≤ 5 times upper limit of normal
  • Serum Creatinine ≤ 2 times upper limit of normal
  • Subjects must have the following hematologic function parameters: Hemoglobin (Hb) level > 8 g/dL; Absolute Lymphocyte Count > 0.1x10^9/L; Platelet > 50x10^9/L

• Prior therapy wash-out. At least 2 weeks or 5 half lives, whichever is shorter, must have elapsed since any prior systemic therapy at the time the subject is planned for leukapheresis.

• Subjects' parent or legal guardian must have the ability to understand and the willingness to sign a written informed consent document.

Exclusion Criteria:

• Autologous transplant within 6 weeks of planned CAR T cell infusion.
• Recipient of CAR-T cell therapy outside of this protocol.
• Active central nervous system (CNS) or meningeal involvement by tumor.
• History of additional active malignancy other than non-melanoma skin cancer, carcinoma in situ (e.g. cervix, bladder, breast).
• Active human immunodeficiency virus (HIV) infection.
• Subjects with uncontrolled intercurrent illness including, but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, pulmonary abnormalities or psychiatric illness/social situations that would limit compliance with study requirements.
• Pregnant or breastfeeding women.
• Evidence of myelodysplasia or cytogenetic abnormality indicative of myelodysplasia on any bone marrow biopsy prior to initiation of therapy.
• Serologic status reflecting active hepatitis B or C infection.