FDA makes recommendations on medical devices that treat blocked heart arteries

U.S. Food and Drug Administration Commissioner Andrew C. von Eschenbach has announced that the agency has issued draft guidelines to aid the development, testing and manufacture of coronary drug-eluting stents, devices used to treat blocked heart arteries.

Over the past few years, FDA and the clinical community have been closely monitoring these devices, including concerns over clot formation in some patients several years after implantation. The draft guidelines issued today—called an FDA guidance document—outline the agency's recommendations for pre-market clinical evaluation and post-market studies, which may provide data to better address this and other potential safety concerns.

Each year in the United States, approximately one 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 of these patients are treated with drug-eluting stents, a scaffolding device that is placed into the arteries to prop them open. Drug-eluting stents have a coating that slowly releases a drug to prevent the growth of scar tissue that may accumulate after the initial procedure opens the artery. Re-accumulation of scar tissue can mean additional procedures to keep arteries open and preserve adequate blood flow.

"This draft guidance is part of FDA's ongoing effort to provide regulated industry with recommendations on measures that can minimize the risks while preserving for patients the benefits of drug-eluting stents," said Daniel G. Schultz, M.D., director of FDA's Center for Devices and Radiological Health.

This draft guidance, announced in today's Federal Register, http://www.gpoaccess.gov/fr/index.html, discusses the development pathway for new drug-eluting stents and provides recommendations on information necessary for a complete marketing submission. It also provides guidance on assessing the toxicity of the drug used to coat the stent, both on its own and as part of the complete product. Because these stents combine device and drug technology, this guidance contains expertise and input from two agency centers—the Center for Devices and Radiological Health and the Center for Drug Evaluation and Research.

Also included are draft recommendations for engineering tests, biocompatibility tests, and animal studies to assess the device's overall safety.

"This guidance demonstrates how FDA will need to work across traditional product boundaries to guide the development of innovative new products," said Janet Woodcock, M.D., director of FDA's Center for Drug Evaluation and Research.

Currently, FDA has approved three coronary drug-eluting stents.

A copy of the guidance, "Draft Guidance for Industry on Developing Coronary Drug Eluting Stents," can be found at http://www.fda.gov/cdrh/ode/guidance/6255.html.

FDA is planning a public workshop on drug-eluting stents, in part as one means of soliciting comments on this guidance.