Safety of Gene Therapy for Parkinson Disease

Along with the loss of dopaminergic neurons in the substantia nigra, Parkinson disease (PD) is characterized by decreased production of γ-aminobutyric acid (GABA), which leads to hyperactivity of the subthalamic nucleus. In animal models of PD, therapy with the gene for glutamic acid decarboxylase (GAD), which catalyzes GABA synthesis, has led to clinical improvement.

Now, an international team has reported the first results in humans of this gene therapy for treating an adult neurodegenerative disorder. In this open-label safety study, which was sponsored by the company that developed the gene therapy technology, researchers followed 12 patients with advanced PD (11 male; age ≤70 years) for 12 months after an adeno-associated virus vector c…