FH-FOLR1 Chimeric Antigen Receptor T Cell Therapy for Treating Pediatric Patients With Relapsed or Refractory Acute Myeloid Leukemia

Inclusion Criteria: * Subject age ≤ 6 years. * Weight ≥ 7 kilograms. * AML that expresses FOLR1 by flow cytometry as assessed by Hematologics, Inc. Laboratory and meets one of the below definitions: * For subjects who have previously received an allogeneic hematopoietic cell transplantation (HCT), any evidence of AML re-emergence post HCT detectable by flow cytometry. * First relapse of AML ≤ 6 months from initial diagnosis. * First relapse of AML \> 6 months from initial diagnosis with minimal residual disease (MRD) ≥ 0.05% by flow cytometry after at least one re-induction attempt (one cycle of therapy). * Second or greater relapse of AML. * Refractory AML, defined as ≥ 0.1% leukemic cells determined by flow cytometry or \> 1% on biopsy after 2 cycles of chemotherapy. * Able to tolerate apheresis. * Life expectancy ≥ 8 weeks. * Has an appropriate stem cell donor source identified. * Lansky performance status score of ≥ 50. Subjects who are unable to walk because of paralysis, but who are up in a wheelchair, will be considered ambulatory for purposes of assessing performance status. * The subject must discontinue all anticancer agents and radiotherapy and, in the opinion of the investigator, have fully recovered from significant acute toxic effects of all prior chemotherapy, immunotherapy, and radiotherapy: * Chemotherapy and biologic agents: All chemotherapy and biologic therapy not specifically mentioned below must be discontinued ≥ 14 days prior to enrollment…