This clinical trial is focused on studying a type of blood cancer called acute lymphoblastic leukemia (ALL), which can be difficult to treat when it comes back or does not respond to standard treatments. The study is specifically for children, adolescents, and young adults who have this condition. The trial will explore the use of two different cell therapies: CART 19/22 T cells and CART45RA-NKG2D cells. These treatments involve using special cells that are designed to target and fight the cancer cells in the body. The CART 19/22 T cells are used for a type of ALL that involves certain markers called CD19 and CD22, while the CART45RA-NKG2D cells are used for another type of ALL known as T-ALL.
The purpose of the study is to determine how safe and feasible these treatments are for patients. Participants will receive the treatment through an intravenous infusion, which means the cells are given directly into the bloodstream. The study will monitor the patients to see how their bodies respond to the treatment and to check for any side effects. Some participants may receive a placebo, which is a substance with no active treatment, to help compare the effects of the actual treatment.
Throughout the study, researchers will collect samples from the patients, such as blood and bone marrow, to understand how the treatment is working. They will also look at specific markers in the cancer cells and the patients’ immune responses. The trial aims to provide valuable information on whether these new cell therapies can be a safe and effective option for treating relapsed or refractory acute lymphoblastic leukemia in young patients.



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