The US Food and Drug Administration (FDA) has approved Orchard Therapeutics’ Lenmeldy (atidarsagene autotemcel) to treat children with pre-symptomatic late infantile, pre-symptomatic early juvenile or early symptomatic early juvenile metachromatic leukodystrophy (MLD).
The approval marks the autogulous hematopoietic stem cell-based gene therapy as the first FDA-approved gene therapy for paediatric patients living with the rare genetic disease.
Estimated to affect one in every 40,000 individuals in the US, MLD is a debilitating disease that affects the brain and nervous system.
The decision was based on data from 37 paediatric patients with early-onset MLD who were enrolled in two single-arm, open-label clinical studies or treated under European expanded access frameworks and who received a one-time administration of Lenmeldy compared with natural history data.
With more than 12 years of follow-up, treatment with Lenmeldy significantly extended overall survival in patients and resulted in the preservation of motor function and cognitive skills in the majority of late infantile MLD patients, as well as some early juvenile MLD patients.
In addition, 85% of the patients had normal language and performance IQ scores and all children with pre-symptomatic late infantile MLD were alive at six years of age, compared to 58% of children in the natural history group.
Furthermore, in patients aged five years, 71% were able to walk without assistance.
Nicole Verdun, director, office of therapeutic products, FDA’s Center for Biologics Evaluation and Research, commented: “This approval represents important progress in the advancement and availability of effective treatments, including gene therapies, for rare diseases.”
Bobby Gaspar, co-founder and chief executive officer, Orchard Therapeutics, said: “This achievement is the culmination of decades of research and development” and “we look forward to ensuring broad and sustainable access to this remarkable innovation for eligible patients in need”.
Already approved in the EU, UK and Switzerland, the gene therapy was granted priority review in September 2023 and was previously given rare paediatric disease and regenerative medicine advanced therapy designations by the FDA.
In addition to the approval, Orchard Therapeutics will transfer its priority review voucher for Lenmeldy to GSK in accordance with the terms of the original licensing agreement.