This study aims to explore a new type of magnetic resonance imaging (MRI) called Chemical Exchange Saturation Transfer (CEST) in children aged 6-18 years with brain tumors. An MRI is a machine that takes detailed pictures of the brain. The CEST MRI used in this study is still being tested and has not been approved by the FDA yet. The study wants to find out if this new type of MRI can help doctors evaluate brain tumors. CEST MRI creates images using water molecules and protons in the brain. Early research shows that CEST could be helpful in understanding brain tumor changes.

This study will enroll 5 participants.

The purpose of this research study is to determine if certain markers in your blood are increased over the duration of your chemotherapy, especially as you get sicker, such as developing a severe infection (sepsis) or severe respiratory failure (acute respiratory distress syndrome).

CAR T cell therapy has shifted the treatment landscape for pediatric and young adult patients with advanced B-cell leukemias. However, the manufacturing process remains in its first generation: difficult, time-consuming, and not automated. The time and significant resources in this process can result in patient safety issues - with patients growing sicker, with harder to control leukemias - in the waiting period. Use of the CliniMACS Prodigy platform can help to surmount these issues. This study will determine the safety and usefulness of using the CliniMACS Prodigy platform to manufacture huCART19 cells.

This is a Phase 1/2b trial for the treatment of patients with either advanced or refractory B cell Acute Lymphoblastic Leukemia or B-lineage lymphoblastic lymphoma who will be treated with huCART19, which has been manufactured using the CliniMACs Prodigy Platform. Possible procedures include medical record review, apheresis, huCART19 infusion, blood draws, physical exams, imaging, and disease assessments through bone marrows and lumbar punctures. Overall, approximately 89 subjects will be enrolled on this clinical trial.

This study involves taking a study drug called SAR443579. The overall goal of this study is to find out if the study drug is safe and effective at treating adults and children with relapsed or refractory acute myeloid leukemia (R/R AML), high risk myelodysplastic syndrome (HR-MDS), or B-cell acute lymphoblastic leukemia (B-ALL). This is a first-in-human research study.