FDA Enters Stent Safety Debate

March 26, 2008 -- To get new drug-coated stents approved, makers of the artery-opening devices will have to focus on patient issues, FDA draft guidelines say.

After balloon angioplasty unclogs arteries, mesh tubes called stents are used to prop the arteries open. Newer stents are coated with chemicals that prevent reclogging. But these drug-eluting stents slow healing, adding a small but serious risk of deadly blood clots.

After the FDA approved three of these devices, doctors have struggled to understand exactly when drug-coated stents should be used, and how best to prevent blood clots. Currently, it's recommended that patients getting these stents should receive anticlotting treatment with Plavix for at least a year.

Proposed Guidelines for Drug-Eluting Stents

Now the FDA has proposed new guidelines for makers of new drug-eluting stents. To get approved, the agency suggests, stent makers will have to perform studies showing:

• The effects the new devices have on reducing patient deaths, heart attacks, and need for repeat procedures.
• Overall rates of death and heart attack in patients receiving the new stents.
• The rate at which blood clots occur in patients receiving the new stents.
• The impact of anticlotting treatment on patients, including how well patients comply with the treatment, how often patients need extended anticlotting treatment, how often anticlotting treatment has to be interrupted, the number of surgical procedures deferred due to anticlotting treatment, and the rate of significant bleeding complications of anticlotting treatment.

In addition, the FDA requires information on the safety of all drugs given off by the stents.

"This draft guidance is part of FDA's ongoing effort to provide regulated industry with recommendations on measures that can minimize the risks while preserving for patients the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," Daniel G. Schultz, MD, director of the FDA's Center for Devices and Radiological Health, says in a news release.

The proposed guidelines also help device makers understand what the FDA needs for approval of products that are both medical devices and drugs.

These aren't small issues. Every year, about a million Americans undergo procedures to treat blocked arteries near the heart. About 650,000 of these patients receive drug-eluting stents.

The FDA plans to hold public hearings to discuss the proposed guidelines.