FDA Releases Drug Coated Stent GuidelinesMar 27, 2008 | Parker Waichman LLP
Drug coated stents should be subject to more stringent clinical trials before approval, and makers of such devices should conduct long-term follow-up studies after drug coated stents are brought to market, according to the Food & Drug Administration (FDA). Those recommendations were part of the FDA's proposed guidelines for drug coated stents that were released yesterday. While the proposal is not binding, companies often seek the FDA's advice during product development, and will follow such guidelines in order to ensure approval of medical devices.
Stents are lattice-like devices that act like scaffolding to hold a blood vessel open. According to the FDA, each year in the United States, approximately 1 million patients undergo procedures to treat coronary atherosclerosis, also known as hardening or blockages of the heart arteries -- a condition that can cause angina and heart attacks. Some 650,000 patients are treated with drug-eluting stents that are coated with a medication that prevents the growth of scar tissue. Currently, Johnson & Johnson, Boston Scientific Corp and Medtronic Inc make the drug-coated stents now on the market. Abbott Laboratories Inc also is expected to receive approval for a new drug-coated stent.
In 2006, the safety of drug coated stents was called into question when the Cleveland Clinic published an analysis of fourteen stent studies covering more than 6,000 patients that found those with drug coated stents were four to five times more likely to suffer from blood clots than those implanted with bare metal stents. Since then, use of the drug coated stents has dropped dramatically.
According to The Wall Street Journal, the proposed drug coated stent guidelines would mark the first concrete change since the FDA held a two-day meeting in December 2006 about whether such stents increase the risk of clots compared with bare-metal stents years after the procedure. The guidelines aren't expected to affect drug coated stents already on the market, but cold delay stents in development.
According to Bloomberg News, the draft guidance calls for drug coated stent makers to undertake new testing to identify the medicines used and show how the drugs break up in the body. The tests need to be done before trials in humans start, the FDA said. The agency also recommended longer human studies, larger safety databases and continuing studies of patients after devices reach the market.
Under the proposal, instead of assessing patients' progress and health in trials nine months after a stent is implanted, the agency will now require companies to submit trial data on patients' health one and two years after the procedure, before stents can be approved. The FDA said that after a drug coated stent is approved, companies should continue monitoring, preferably for five years after implantation, for blood clots, heart attack or other complications.