February 20, 2009 – Doctors could soon treat patients with resistant obsessive-compulsive disorder (OCD) with an implantable device that stimulates the brain to block nerve signals that may cause OCD symptoms.
The US Food and Drug Administration (FDA) has announced approval of a humanitarian device exemption (HDE) for the deep brain stimulator. Such exemptions facilitate the development and marketing of medical devices that treat or diagnose a disease or condition that affects fewer than 4000 people a year in the United States.
Because these devices would help relatively few patients, their research and development costs could exceed their market returns. To receive this exemption, a company must demonstrate the safety and probable benefit, but it does not have to produce results of clinical investigations showing that the device is effective for its intended purpose.
In this case, the small battery-powered deep brain stimulator — called Reclaim DBS Therapy (Medtronic, Minneapolis, Minnesota) — is implanted near the abdomen or the collarbone and connected through a lead to electrodes in the brain. The device delivers intermittent electrical stimulation that blocks nerve signals. One device may be implanted with 2 leads, or 2 systems can be implanted to stimulate both sides of the brain.
Device Not a Cure
The Reclaim is designed to treat patients with severe OCD who have failed 3 or more drug treatments and psychotherapy.
OCD is an anxiety disorder characterized by recurrent obsessive thoughts and/or repetitive compulsive behaviors. Individuals with OCD often exhibit these repetitive behaviors to try to prevent obsessive thoughts. When individuals perform these actions, they get only temporary relief, but not performing them increases their anxiety. An estimated 1 in 50 adults in the United States has some OCD symptoms.
Deep brain stimulation may provide relief to some patients with severe OCD but it is not a cure, Daniel Schultz, MD, director of the Center for Devices and Radiological Health, said in a statement. "Individual results will vary, and patients implanted with the device are likely to continue to have some mild to moderate impairment in functioning and continue to require medications."
The approval of the HDE was based on a review of data from 26 patients with severe treatment-resistant OCD who underwent the deep brain stimulation at 4 sites. On average, patients had a 40% reduction in their symptoms after 12 months of therapy.
Patients who should not use the Reclaim device include those who require electroconvulsive shock therapy and those who will undergo magnetic resonance imaging (MRI) or deep tissue heat treatment known as diathermy. According to the FDA Web site, while an HDE application does not have to contain results of clinical investigations showing that the device is effective for its intended purpose, it must contain sufficient information to determine that the device does not pose a significant risk for illness or injury and that the probable benefit to health outweighs the risk for injury or illness from its use.