Cincinnati Children’s Hospital reports remarkable success in treating a young patient with Aromatic l-amino acid decarboxylase (AADC) deficiency using gene therapy. Sriansh Ojha, who at 16 months became the youngest recipient of the therapy, is now thriving, demonstrating motor skills previously unattainable due to his condition.
FDA Approves KEBILIDI™ for AADC Deficiency
The U.S. Food and Drug Administration (FDA) approved KEBILIDI™, a gene therapy developed by PTC Therapeutics, on November 13, 2024. This marks the first gene therapy approved in the United States that is directly administered to the brain. The therapy aims to correct the underlying genetic defect in AADC deficiency, a rare inherited disorder affecting neurotransmitter production.
How KEBILIDI™ Works
AADC deficiency results from mutations in the DDC gene, leading to a deficiency in the AADC enzyme necessary for producing dopamine and serotonin. KEBILIDI™ delivers a functional copy of the DDC gene to the putamen, a brain region crucial for motor control and cognitive function, using an adeno-associated virus (AAV9) vector. This enables the brain cells to produce the missing enzyme, restoring neurotransmitter production.
Clinical Trial Results and Impact
Sriansh Ojha participated in a clinical trial that supported the FDA approval. Before the gene therapy, Sriansh exhibited severe symptoms, including muscle weakness, inability to lift his head, and uncontrolled eye movements. Following the therapy, he has shown remarkable improvement, now able to sit up on his own and move more freely.
According to Donald Gilbert, MD, MS, a movement disorder expert at Cincinnati Children’s, the early intervention contributed to Sriansh's positive outcome. Adjustments to the surgical procedure were made to accommodate Sriansh's young age, including modifications to the apparatus, burr hole size and location, and anesthesia protocol, as detailed by Sudhakar Vadivelu, DO.
The Future of AADC Deficiency Treatment
The approval of KEBILIDI™ represents a significant advancement in treating AADC deficiency. Early diagnosis is now possible through blood spot testing, similar to screening for other genetic conditions like PKU. This allows for prompt intervention and potentially better outcomes for affected children. The success also suggests the possibility of gene therapy for other genetic brain disorders.
Long-term follow-up will continue to assess Sriansh's developmental progress, focusing on motor and cognitive functions. His progress to date indicates significant gains, with developmental milestones advancing several months in a matter of weeks.
