FDA Considers Approval of Vagus Nerve Stimulator for Depression

The Food and Drug Administration (FDA) may soon approve a novel treatment for severe depression, a condition that affects millions of Americans, despite concerns about its limited effectiveness. The treatment, a vagus nerve stimulator, was originally approved in 1997 for epilepsy patients and has since been studied as a potential treatment for depression. The device, surgically implanted in the upper chest, sends mild electrical pulses to the vagus nerve, which leads to the brain, where they are believed to stimulate areas that regulate mood.

Key Takeaways:

• The vagus nerve stimulator has been approved for epilepsy patients since 1997, but its effectiveness for treating depression is still uncertain.
• A recent study involving 235 severely depressed patients found that the device was no more effective than a sham procedure, with only 17 patients showing significant improvement.
• Critics argue that the evidence for the device's effectiveness is limited, and that the FDA is considering approval based on anecdotal testimonials and favorable responses from a small subset of patients.
• Patient advocates and some experts are concerned that the FDA is moving too quickly to approve the device, and that it may lead to widespread use without sufficient evidence of its benefits.
• The FDA often follows the recommendations of advisory panels, which in this case voted 5 to 2 to recommend approval of the device.
• The agency has given mixed signals about the device, initially telling the manufacturer that it was not approvable, but later changing its position and informing the company that the device could be approved.
• The company's stock price has fluctuated as investors try to anticipate the FDA's decision, which is expected by the end of the month.

Statistics:

• 235 patients were involved in the study of the vagus nerve stimulator for depression.
• 17 patients (7.3%) showed significant improvement in the study.
• Only 11 of 110 patients (10%) without stimulation felt significantly better.
• 30% of patients in the study showed significant improvement on one measure of depression after six months or more.
• The device's pulse is typically turned up higher over time, but some patients have reported negative side effects, including hoarseness and suicidal thoughts.

Sources:

• The New York Times, August 19, 2004
• FDA documents, as cited in the article
• Public Citizen, a nonprofit advocacy group critical of the FDA and the drug industry
• Cyberonics Inc., manufacturer of the vagus nerve stimulator
• Senate Finance Committee, which has launched an investigation into the FDA's potential reversal on approval.