Metachromatic leukodystrophy is a rare inherited disorder that slowly damages the protective coating of nerve cells, leading to problems with movement, learning and daily activities. The study uses a gene‑therapy product called OTL-200, which contains specially prepared cells that are given through an intravenous infusion to try to replace the missing enzyme and slow the disease’s progression.
The purpose of the study is to watch for any long‑term safety concerns, specifically the chance of developing malignancy caused by insertional oncogenesis, a process where the therapy’s genetic material might unintentionally trigger cancer. After receiving the infusion, participants will have regular sample collections over many years so doctors can check for signs of cancer or unusually high levels of altered cells. This monitoring helps ensure that any potential risks are identified early while the treatment’s benefits continue to be evaluated.



France
Germany
Italy
Sweden
The Netherlands