A new therapy device to cure treatment-resistant chronic depression has shown continued efficacy in post-marketing studies.
The new therapy called Vagus Nerve Stimulation therapy developed by Cyberonics electronic impulsed in low, medium and high levels to treat depression.
The U.S. Food and Drug Administration had approved Cyberonic’s Vagus Nerve Stimulation therapy for treatment-resistant depression, in July 2005. However, US FDA had asked Cyberonics to conduct a long-term post-marketing study.
Cyberonics announced the results of a multicenter, double-blind, randomized dosing study.
This dosing study showed a consistent, sustained and clinically meaningful decrease in depression symptoms.
The study compared the safety and effectiveness of VNS Therapy administered at different stimulation levels to 331 adult patients enrolled at 29 U.S. study centers.
Patients were randomized to receive one of three stimulation levels (low, medium or high) during the acute phase (22 weeks).
The study design allowed patients in the low and medium stimulation groups to receive increased levels of stimulation after 22 weeks. Patients were followed in the study for a total of 54 weeks.
Patients participating in this dosing study were experiencing very severe levels of chronic and recurrent treatment-resistant depression that had been unresponsive to multiple antidepressant treatments.
Patients receiving high stimulation did not show significantly greater improvement than those receiving medium or low stimulation at the end of the 22-week acute phase.
The overall trend and magnitude of depression symptom decrease is consistent with prior long-term VNS Therapy studies in similar patient populations experiencing chronic and recurrent treatment-resistant depression.
“Chronic and recurrent treatment-resistant depression is a very debilitating illness–many of these people suffer for years without any improvement despite numerous treatment trials,” stated Charles R. Conway, M.D., Associate Professor of Psychiatry at Washington University School of Medicine and research faculty at St. Louis University School of Medicine.
Chronic and recurrent treatment-resistant depression patients are rarely included in clinical studies and very few effective treatment options exist for them, he added.
The VNS Therapy System uses a surgically implanted medical device that delivers pulsed electrical signals to the vagus nerve.
It takes approximately 1 hour and generally performed on an outpatient basis. The procedure is typically performed under general anesthesia.
VNS Therapy does not directly involve the brain and can be performed by surgeons with a variety of specializations.
So far, the therapy has been used to treat more than 50,000 epilepsy patients worldwide Cyberonics markets the VNS Therapy System in approximately 60 countries worldwide, and to date more than 55,000 patients have been implanted with the device.
Cyberonics, Inc is a medical technology company with core expertise in neuromodulation.