The alleged failure of the U.S. Food and Drug Administration to ensure the safety of medical devices is the subject of an investigative report, "Why the FDA can't protect the public," co-authored by Dartmouth researcher Shannon Brownlee.
Brownlee, a Dartmouth Institute for Health Policy and Clinical Practice instructor, and Jeanne Lenzer, a medical investigative journalist, released a year-long study examining the 1997 approval of Cyberonics's vagus nerve stimulator. The device may have induced fatal seizures in epileptic patients, according to the study, published on Nov. 2 in the British Medical Journal.
The company claimed that the device could prevent or reduce seizures in epileptic patients who did not respond to drug treatments. The implant a matchbox-size generator placed under the skin below the patient's collarbone transmits 30-second electrical impulses through the left vagus nerve every three to five minutes. Before the device was approved in the United States, 17 of the 1,000 patients worldwide who received implants died most of them from "sudden unexpected death from epilepsy," a condition connected to an epileptic seizure that is thought to cause cardiac arrest, according to the report.
During a meeting with the FDA, Cyberonics told the panel that the device was safe. One panelist Steven Piantadosi, at the time a professor of oncology and biostatistics at Johns Hopkins University however, raised questions about the device's death rates, according to the report. The panel nonetheless approved the device on the condition that Cyberonics conduct a post-approval study on the device's safety.
"It is still not clear what impact, if any, the device has had on patient mortality," the report said.
In the 13 years since the device was approved, more than 900 deaths of people using the device were reported to the FDA, but without specific details concerning reasons for death.
"We decided to pursue the study because we knew that there were long-standing problems with post-marketing surveillance of devices, and we've known that from issues with other devices," Brownlee said in an interview with The Dartmouth.
The report charged that the FDA's monitoring of the stimulator was indicative of the agency's general lack of oversight of medical devices.
Brownlee said that solutions to the problem "are pretty simple." She suggested that the agency make better use of an existing Manufacturer and User Facility Device Experience Database, which documents the safety and effectiveness of devices in everyday circumstances. The database requires manufacturers to submit data regularly concerning the population using the device and to have an independent panel review the data.
"If a Boeing 747 crashes, Boeing is not the one who gets to decide whether or not the crash was the fault of their own airplane or whether it was pilot error," Brownlee said. "An outside board makes that decision, and by the same token, we need to have an outside board that actually looks at the data on safety in devices."
Representatives from both the FDA and Cyberonics have said that there was no evidence to show that any of the 900 deaths were directly caused by the stimulator.
In an interview with The Washington Post, Karen Riley, a spokesperson for the FDA, said that Cyberonics's post-approval study did not show any signs that the device was causing problems and said that the FDA had taken a number of measures in recent years to improve its post-marketing surveillance.
Brownlee said she believes the agency should be doing more to ensure that products are "safe and effective at best."
"We hope that this gets the attention of Congress, because we think that some of the changes that are needed are going to need to come from better funding of the FDA and a mandate from Congress to do a better job," Brownlee said.
