CD19x22 Chimeric Antigen Receptor T-cell Therapy (CAR T) in Pediatric B-ALL

This study is testing a new type of CAR T-cell therapy — where a patient's own immune cells are engineered to attack cancer — that targets two proteins on cancer cells (CD19 and CD22) at the same time. It is designed for children and young adults with B-cell acute lymphoblastic leukemia (B-ALL) that has relapsed or stopped responding to standard treatments. **You may be eligible if...** - You are aged 3 months to 30 years with B-cell ALL that has relapsed or is treatment-resistant - Your leukemia has relapsed at least twice, relapsed after a bone marrow transplant, relapsed or failed after CAR T-cell therapy, or your doctors have determined standard therapy is not working - Your cancer still expresses CD19 and/or CD22 markers - You have adequate functional status (Lansky or Karnofsky ≥ 50%) **You may NOT be eligible if...** - You have active, uncontrolled central nervous system leukemia - You have received a prior CAR T infusion within the last 90 days - You have severe organ dysfunction - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.