Patients with the rare and fatal disorder could improve their gross motor function through infusions to the brain
The FDA has approved a gene therapy called Kebilidi for patients with aromatic L-amino acid decarboxylase (AADC) deficiency.
Kebilidi is the first FDA-approved gene therapy treatment for the rare and fatal genetic disorder.
“AADC deficiency can cause a range of debilitating symptoms, including life-threatening complications,” said director of the Office of Therapeutic Products in the FDA’s Centre for Biologics Evaluation and Research (CBER) Dr Nicole Verdun.
“Today’s approval represents important progress in the advancement and availability of safe and effective treatments for debilitating genetic disorders.”
AADC deficiency affects the production of neurotransmitters, delaying gross motor function such as head control, sitting, standing and walking, and inducing hypotonia (weak muscle tone). Those with AADC deficiency also experience physical, cognitive and behavioural delays.
Ultimately, those with AADC deficiency may struggle with life-threatening complications, such as infections and severe feeding and breathing problems.
Kebilidi is an adeno-associated virus vector-based gene therapy containing the human DDC gene. Patients undergo a stereotactic surgical procedure using imaging to administer four infusions directly into the putamen.
The putamen’s primary function in the brain is to regulate movement, speech and cognitive functioning.
The aim is to increase the AADC enzyme and restore dopamine production, a critical neurotransmitter in the brain associated with movement, attention, learning and memory.
Kebilidi was approved using the FDA’s Accelerated Approval pathway following a study examining its effects on 13 patients with severe AADC deficiency and no gross motor function.
Motor milestone assements were completed for 12 of the 13 patients 48 weeks after receiving the infusions. Of the 12 patients, eight experienced improvements in their gross motor function. The patients were compared with untreated patients who did not experience such improvements.
“Clinical advancements in the field of gene therapy continue to lead to the discovery and availability of innovative treatment options for rare diseases that are otherwise difficult to manage,” said director of the CBER Dr Peter Marks.
“Today’s approval underscores our commitment to help make safe and effective treatments available for patients in need.”
A confirmatory trial is ongoing to verify Kebilidi’s clinical benefit.
