Today, from Revio, we are thrilled to share that the U.S. Food and Drug Administration recently approved Lenmeldy (atidarsagene autotemcel), the first gene therapy indicated for the treatment of children with pre-symptomatic late infantile, pre-symptomatic early juvenile or early symptomatic early juvenile metachromatic leukodystrophy (MLD).

Metachromatic Leukodystrophy

Metachromatic Leukodystrophy is a debilitating, rare genetic disease that affects the brain and nervous system, and it is caused by a deficiency of an enzyme called arylsulfatase A. This deficiency leads to a buildup of sulfatides in the cells, causing damage to the central and peripheral nervous system. The disease manifests with loss of motor and cognitive function and early death and is estimated to affect one in every 40.000 individuals in the United States.

There is no cure for this condition, and treatment normally focuses on supportive care and symptom management, so this represent an important milestone in the field of the rare genetic diseases and the gene therapies.

Lenmeldy (atidarsagene autotemcel)

Lenmeldy is a one-time, individualized single-dose infusion made from the patient’s own hematopoietic stem cells, which have been genetically modified to include functional copies of the defective gene. In the patient’s body, the modified stem cells attach and multiply within the bone marrow.

These modified cells will supply the body with immune cells that will produce the defective enzyme, ARSA, which will help breaking down the harmful build-up of sulfatides and may stop the progression of the disease. Prior to this treatment, patients must undergo high-dose chemotherapy, a process that removes cells from the bone narrow so they can be replaced with the modified cells in Lenmeldy.

Clinical trials

Safety and efficacy of Lenmeldy was assessed based on data from 37 children in two single-arm, open-label clinical trials and in an expanded access program. Children who received the treatment were compared to untreated children (natural history). The primary efficacy endpoint was severe motor impairment-free survival, defined as the interval from birth to the first occurrence of loss of locomotion and loss of sitting without support or death.

Treatment with Lenmeldy significantly reduced the risk of severe motor impairment or death compared with untreated children. All children with pre-symptomatic late infantile MLD treated with Lenmeldy were alive at 6 years of age, compared to only 58% of children in the natural history group. At 5 years of age, 71% of treated children were able to walk without assistance. 85% of the children treated had normal language and performance IQ scores, which has not been reported in untreated children.

Expedited Programs

Lenmeldy’s application received Priority Review, Orphan Drug, Rare Pediatric Disease and Regenerative Medicine Advanced Therapy designation. These expedited programs are available to sponsors and developers of innovative medicines targeting rare or severe conditions that show potential benefit. If you want to learn more about FDA’s available expedited programs you can check our review here! https://reviopharma.com/expedited-programs-for-regenerative-medicine-therapies-for-serious-conditions

If you want to get more information on the approval of Amtagvi you can check the official FDA press release here! https://www.fda.gov/news-events/press-announcements/fda-approves-first-gene-therapy-children-metachromatic-leukodystrophy

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We hope you find this insightful and interesting. If you would like to discuss any of these updates with the team at REVIO, please get in touch here.