Phase 3 trials must be conducted before the U.S. Food and Drug Administration decides whether to approve the treatment for general use.
The therapy, which was done with local anesthesia, used a harmless, inactive virus to deliver the GAD gene into each patient's subthalamic nucleus, a key brain region involving motor function. The gene instructs cells to begin making GABA neurotransmitters to re-establish the normal chemical balance that becomes dysfunctional as the disease progresses.
At the six-month mark, patients in the gene therapy group who had been off their medications for 12 hours showed an average 23.1 percent improvement on a scale used to assess motor function in Parkinson's patients, while placebo patients had a 12.7 percent improvement.
"For the first time, we're one step closer to a gene therapy for any neurological disease, because we passed this hurdle," said study co-author Dr. Michael Kaplitt, vice chairman for research in the department of neurological surgery at Weill Cornell Medical College in New York City.
"I think we're closer than we've ever been to be able to realistically tell patients . . . they can get this done," said Kaplitt, also a co-founder of Neurologix Inc., the Fort Lee, N.J. company that is developing the GAD therapy and that funded the current study. (Several other researchers also have financial ties to Neurologix and/or a patent related to the GAD product.)
Another surgical procedure, known as deep brain stimulation, which permanently implants a nerve control device in the brain, has helped control Parkinson's symptoms in thousands of patients over the last decade. Deep brain stimulation is apparently associated with
All rights reserved