Dec. 8, 2006 -- An FDA advisory panel recommended new warnings Friday for popular medical devices used in millions of patients with cardiovascular disease.
Experts said the two brands of drug-coated stents available in the U.S. should carry new warnings that the devices may increase the risk of sudden heart attack or death in patients.
Stents are mesh tubes used to prop open arteries after surgeons clear away blockages, usually with an inflatable balloon procedure called angioplasty. As many as 1 million Americans receive stent implants each year.
The devices are made either of bare metal mesh or a newer coated metal that steadily releases a drug into artery walls to prevent formation of scar tissue. Two drug-coated stents -- Taxus, made by Boston Scientific, and Cypher, made by Cordis -- have exploded in popularity since they came on the market in 2003 and 2004.
Heart Bypass Alternative
Stents are credited with providing a nonsurgical alternative to heart bypass operations for many patients with artery disease. But new data released earlier this year suggested that drug-coated versions may increase the risk of heart attacks and death 18 months to three years after stent implantation.
The data and resulting media coverage prompted the FDA to organize a hastily convened two-day session of an expert panel to decide how the agency should proceed. Friday's conclusions came one day after the panel informally voted that the benefits of drug-coated stents outweigh the risks for average patients.
Studies leading to the approval of Taxus and Cypher tested the devices in patients with single, smaller artery blockages. But doctors quickly started using them in more complicated patients with blockages in multiple vessels and in those with larger blockages.
"If [doctors] use the device in an off-label manner they're not going to get the results that they see in the label," said William H. Maisel, MD, a cardiologist at Beth Israel Deaconess Medical Center in Boston and chairman of the advisory panel. "Off-label" means using drugs or devices in ways not approved by the FDA.
Today more than 60% of all drug-coated stent implants are "off-label," according to the FDA.
Experts also said doctors should be urged to extend the use of the blood-thinning drug Plavix in patients who receive drug-coated stents off-label. Current recommendations advise patients to take Plavix along with aspirin for three to six months after stent placement, though experts said that should be extended to one year.
The recommendations were not made by a formal vote but were the consensus of panel members. The FDA does not have to follow the advice of advisory panels, but it usually does.
Options for the FDA
FDA officials said they would move to communicate the recommendations to the public, though the method of that communication is yet to be decided. The agency could choose to add warnings to drug-coated stent labeling, communicate directly with doctors about the risks, or both.
"At the end of the day what I heard loud and clear is that we need to do a better job ... communicating to patients and communicating to doctors the best and the latest information," said Dan Schultz, MD, director of FDA's Center for Devices and Radiologic Health. "This meeting needed to happen."
News of the potential for increased risk sparked anxious news reports and worry among many U.S. patients. Experts stressed Friday that there was little need for patients with drug-coated stents to have them removed. Suspected clots and heart attacks blamed on the stents are still thought to be relatively rare. Patients who take blood-thinning drugs according to doctors' recommendations reduce their risk.
Some experts described the two days of FDA meetings as a kind of reality check on the use of drug-coated stents by U.S. doctors
"I think we've got to come back to earth here," said Steven Nissen, chairman of cardiovascular medicine at The Cleveland Clinic and one of the FDA advisors.
Still, there was some dissent among panel members. Some worried that issuing new warnings would further frighten patients and doctors away from using the stents.
"I haven't seen anything today that's going to change my practice on Monday morning when I go back," said Christopher J. White, chairman of cardiology at the Ochsner Clinic Foundation in New Orleans and a member of the FDA panel.
Mark Turco, MD, a researcher at Washington Adventist Hospital in Washington, D.C., said that drug-coated stents were greeted by "unbridled enthusiasm" that outpaced scientific proof for many patients. He said recent news of increased risks then swung public perception to one of near-panic over the dangers.
"Hopefully we will soon move to a realistic application where the data will far outweigh the perceptions," he said.