In October 2025, the gene therapy OTL-200, developed by Kyowa Kirin and Orchard Therapeutics, was granted 'Orphan Regenerative Medicine Product' designation by the Ministry of Health, Labour and Welfare, bringing a revolutionary therapeutic hope to children suffering from early-onset metachromatic leukodystrophy (MLD).

Principle of the treatment: OTL-200 is a type of ex vivo autologous hematopoietic stem cell gene therapy. It involves extracting a patient's own hematopoietic stem cells and using a lentiviral vector to introduce a functionally normal ARSA gene into the cell genome. These repaired cells are then returned to the patient's body, with the expectation of correcting the disease at its root.

Current status of the disease: MLD is a fatal and rare neurodegenerative disorder for which there is currently no effective treatment in Japan. Once children develop the disease, they gradually lose the ability to walk and speak, and many pass away within five years of symptom onset.

Significant Implication: This certification indicates that the significance of OTL-200 as an innovative therapy has been officially recognized. Currently, Kyowa Kirin is actively preparing clinical trials for this therapy in Japan, striving to bring hope to patients' homes at an early stage.