The study follows patients with Advanced lymphoid leukemia who have previously received an infusion of the experimental cell therapy called UCART19. This therapy consists of donor‑derived T cells that have been engineered to carry a CAR that recognizes the protein CD19 on the surface of the cancer cells. The cells are also modified by removing the genes TRAC and CD52 to reduce the risk of the immune system attacking the infused cells.
The purpose of the study is to evaluate the long‑term safety of the therapy. After the original infusion, participants will attend regular clinic visits over several years during which doctors will check for any health problems, record any side effects, and collect blood samples. Children will have additional assessments to see whether growth or puberty are affected.
During follow‑up, routine tests may include blood work, imaging scans if needed for clinical care, and, when part of standard care, a bone‑marrow sample to look for the engineered cells. All information gathered will be used only to understand how the therapy behaves over time and to identify any late‑appearing safety issues.
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