CD19/CD22 Bicistronic Chimeric Antigen Receptor (CAR) T Cells in Children and Young Adults With Recurrent or Refractory CD19/CD22-expressing B Cell Malignancies

Background: Acute lymphoblastic leukemia (ALL) is the most common cancer in children. About 90% of children and young adults who are treated for ALL can now be cured. But if the disease comes back, the survival rate drops to less than 50%. Better treatments are needed for ALL relapses. Objective: To test chimeric antigen receptor (CAR) therapy. CARs are genetically modified cells created from each patient s own blood cells. his trial will use a new type of CAR T-cell that is targeting both CD19 and CD22 at the same time. CD19 and CD22 are proteins found on the surface of most types of ALL. Eligibility: People aged 3 to 39 with ALL or related B-cell lymphoma that has not been cured by standard therapy. Design: Participants will be screened. This will include: Physical exam Blood and urine tests Tests of their lung and heart function Imaging scans Bone marrow biopsy. A large needle will be inserted into the body to draw some tissues from the interior of a bone. Lumbar puncture. A needle will be inserted into the lower back to draw fluid from the area around the spinal cord. Participants will undergo apheresis. Their blood will circulate through a machine that separates blood into different parts. The portion containing T cells will be collected; the remaining cells and fluids will be returned to the body. The T cells will be changed in a laboratory to make them better at fighting cancer cells. Participants will receive chemotherapy starting 4 or 5 days before the CAR treatment. Participants will be admitted to the hospital. Their own modified T cells will be returned to their body. Participants will visit the clinic 2 times a week for 28 days after treatment. Follow-up will continue for 15 years....