Studied extensively, new drug-eluting stent said to be very safe

The Food & Drug Administration recently approved for use Endeavor, the first zotarolimus-eluting coronary stent manufactured by Minneapolis-based Medtronic, Inc.

Endeavor provides a minimally invasive alternative to open-heart bypass surgery for patients undergoing an angioplasty.

Salmon said the clinical program for Endeavor -the first DES to be approved by the FDA since 2004-represents the largest DES regulatory submission in the United States. Conducted over four years, Medtronic provided the FDA with data from seven randomized controlled clinical trials and registries that involved more than 4,100 patients. Post-market follow-up to assess Endeavor's long-term safety and effectiveness and risk of thrombosis will include 22,500 patients and take five years to complete. "We had to call more patients because zotarolimus is a new molecular entity," Salmon explained. "The FDA required a minimum of 2,000 patients studied over a 30-day exposure period. Later, because of safety issues, the FDA required twice the amount of data. The FDA required us to follow up with everyone for five years," he remarked.

To prevent stent thrombosis and restenosis, Endeavor's clinical studies included a regimen of the antiplatelet drugs, clopidogrel and ticlopidine, for a minimum of three to six months both pre- and post-procedure. "Current guidelines recommend that patients receive aspirin indefinitely," states Endeavor's "Instructions for Use."

Jennings, who advises that "for anyone with a stent, it's aspirin for life," noted that 12 months of post-surgical antiplatelet drugs help to prevent platelet activity and encourage the endothelial process. "Once the stent is embedded into the tissue, you don't need antiplatelet drugs because it becomes part of the body," he added.

Medtronic launched Endeavor in February and expects initial shipments to U.S. hospitals to total 100,000 units. Salmon said the stent "is priced in the middle of the market."

Besides Endeavor, another DES is expected to hit the market. It's Abbott's XIENCE V, an everolimus-eluting stent. Approved for use in Europe and Japan, this stent prevents vasculopathy in cardiac-allograft patients and may be approved domestically in the second quarter.

THE AUTHOR is a freelance writer who specializes in health care.