Gene Therapy for Parkinson’s Disease

Although gene therapy has been successful for treating a wide variety of disorders, neurogenerative diseases pose a unique challenge due in part to the blood-brain barrier – a layer of cells that is designed to protect the brain from pathogens and other toxins. But recently, an experimental treatment that utilizes a harmless, non-replicating virus received a fast-track designation by the United States Food and Drug Administration to begin human clinical trials in patients with a specific gene mutation.

A gene known as GBA1 serves to prevent toxins from accumulating inside brain cells. When this gene is not functioning properly, particularly as people age, excessive inflammation may result in the neuro-degeneration that is seen in Parkinson’s disease. Individuals with mutations in the GBA1 gene have as much as five times greater risk of developing Parkinson’s disease, and it is estimated that 7 to 10 percent of all cases are related to mutations in this gene.

The new therapy uses an adeno-associated virus called AAV9 to shuttle engineered DNA across the blood-brain barrier and deliver a working GBA1 gene to the brain. The drug is designed to be a single-dose therapy that should ease symptoms caused by the mutation.