Group Attacks Depression Device Approval
Evidence Lacking Showing VNS Is Effective, Says Watchdog
Peter Lurie, MD, Public Citizen's deputy director, called the approval "one of the most questionable regulatory decisions made by the agency in recent memory.
"Devices for which medical claims are made should meet the same approval criteria as drugs. In effect, the FDA has lowered the approval bar for this device. There is simply no convincing evidence that this device works. Until and unless such data are generated, patients are better off without this device."
Cyberonics, a WebMD sponsor, declined to comment on Public Citizen's criticism of the approval.
The Senate Finance Committee, which has spent the last year and a half probing approval and safety practices at the FDA, several months ago launched an investigation into the FDA's handling of Cyberonics' application for VNS's approval.
The committee's senior Republican and Democrat noted in a joint statement Friday that they would continue their inquiry. "Both the effectiveness and the safety of medical devices must be ensured prior to their approval by the Food and Drug administration," say Sen. Charles E. Grassley (R-Iowa) and Sen. Max Baucus (D-Mont.).
VNS has been on the U.S. market since 1997 as a treatment for severe epilepsy. More than 22,000 patients have used the device, according to Cyberonics.
FDA Defends Approval
The FDA rejected Public Citizen's complaint that the agency lowered its standards for approving VNS for depressed patients. FDA regulations require manufacturers to show "a reasonable assurance of safety" to get devices cleared, while drugs must be shown to be "safe and effective," says FDA spokeswoman Julie Zawisza.
"This device was approved for a very small subset of patients who are very, very sick and have failed all other treatment options and have no other options," she says.
VNS devices will carry "black box" warnings alerting doctors to use the device only in patients who have failed to improve after four or more other types of treatment, Zawisza says.
Richard P. Malone, MD, who served on the expert panel that scrutinized the VNS data, says he was not convinced that the device met the agency's standard for a reasonable assurance of safety or efficacy.
"The only controlled study was negative. So benefit is clearly a problem. The studies did show safety concerns, but I don't think they showed benefit," says Malone, a professor of psychiatry at Drexel University who voted against approving VNS.