Introduction Atidarsagene autotemcel (arsa-cel, Libmeldy™), an ex vivo autologous CD34+ haematopoietic stem cell gene therapy, was approved by EMA in 2020 to treat children with metachromatic leukodystrophy (MLD) with the late infantile (LI) or early juvenile (EJ) forms, without clinical manifestations of the disease, and in children with the EJ form with early clinical manifestations of the disease who still have the ability to walk independently and before the onset of cognitive decline. We share the German treatment experience in Tübingen, including treatment of 2 patients identified by a newborn screening (NBS) pilot study. Methods From 2021, a prospective MLD NBS pilot study using biochemical and genetic testing in DBS was initiated at the Screening Center in Hannover. Identified positive cases have been referred to Tuebingen and were treated according to SOP after myeloablative conditioning with Busulfan. Results So far, out of over 120,000 screens from the NBS study, 3 cases have been identified and diagnosed, 2 of them were classified as EJ form and were treated with arsa-cel at age 11 months. Conclusion Inclusion of MLD into the national NBS programs will enable treatment intervention with arsa-cel for early onset MLD ensuring best possible outcomes.

Annette Elisabeth Bley
University Medical Center Hamburg Eppendorf
Germany

Samuel Groeschel
University Children’s Hospital
Germany

Lucia Laugwitz
University Children’s Hospital
Germany

Niels Janzen
Centre for Children and Adolescents Auf der Bult
Germany

David Kasper

Austria

Peter Lang
Children’s University Hospital
Germany