The study focuses on children, adolescents and young adults who have central nervous system tumours that are classified as high‑grade, meaning they are aggressive and have returned after previous treatment. Two types of modified immune cells are being tested: one is a preparation of the patient’s own natural killer cells that have been grown in the laboratory with the help of interleukin-15 (a protein that boosts immune activity) and is referred to as NKIL15; the other is a preparation of the patient’s own T‑cells that have been altered using a lentiviral vector to add a chimeric antigen receptor that recognizes the protein NKG2D, and is called CART‑NKG2D. Both products are given directly into the area of the brain where the tumor is located.
The purpose of the trial is to determine whether these cell therapies can be given safely to the target group. Participants will first undergo basic health checks, then receive one or two doses of the assigned cell product through a small procedure that delivers the cells into the brain’s fluid spaces. After each dose, they will have regular clinic visits for a few weeks to monitor how they feel and to have simple tests, such as blood draws and fluid samples, to see how the cells behave in the body.
Throughout the study, doctors will closely watch for any side effects, especially reactions that affect the nervous system or cause inflammation. They will also check how long the infused cells remain in the brain’s fluid and whether they can be detected over time. The overall aim is to gather information that could help develop new treatments for these serious brain tumors.
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