The U.S. Food and Drug Administration has approved a humanitarian exemption for the first implantable device to treat severe obsessive-compulsive disorder. The device, known as Reclaim DBS (deep brain stimulation) is made by Medtronic Inc. (MDT).

The product was approved to treat patients with OCD in cases where drug and psychotherapy have failed. It's expected the device could be used in fewer than 4,000 people annually for OCD.

Patients with the disorder battle recurring, obsessive thoughts that can trigger repetitive behavior such as hand washing, counting and cleaning, the FDA said. Medtronic’s device, designed to block abnormal nerve signals in the brain, may help patients who don’t respond to drugs or psychotherapy, said Daniel Schultz, director of the agency’s Center for Devices and Radiological Health, in the statement.

However he said the system isn't a cure for OCD and that patients implanted with the device are likely to continue to have some mild to moderate impairment in functioning and continue to require medications.

The FDA said approval of the Reclaim system was based on information from 26 patients with severe treatment-resistant OCD who were treated with the device. On average, patients had a 40% reduction in their symptoms after 12 months of therapy. While all patients reported adverse events, the majority of these events ended after an adjustment was made in the amount of electrical stimulation applied.

Medtronic has been pursuing research of DBS for psychiatric disorders for more than a decade in collaboration with physicians from many leading institutions. The first DBS implant for treatment-resistant depression was performed in a physician-sponsored study supported by Medtronic at Butler Hospital in Providence, R.I. in 2003.