IPEX syndrome is a rare inherited disorder in which a change (mutation) in the FOXP3 gene prevents the body’s immune system from keeping itself in check, leading to harmful auto‑immune attacks. The study investigates a new therapy that uses a specially prepared cell product called FOXP3-T4, which contains the normal FOXP3 gene delivered by a harmless virus called a lentiviral vector. This product is given through an intravenous infusion to create more functional regulatory T cells, a type of immune cell that helps stop unwanted immune reactions. Some participants also receive a low dose of the medicine aldesleukin, which is a form of the natural protein IL‑2 that supports the growth of these regulatory cells.
The purpose of the study is to see whether the combined approach is safe and can improve immune balance in people with IPEX syndrome. Participants receive the cell infusion once, and those assigned to the additional medication get small injections under the skin at regular intervals. After treatment, patients are followed for up to two years with routine check‑ups to monitor health, any side effects, and signs of improvement in their condition.
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