The US Food and Drug Administration on Friday approved the sale
of Medtronic drug-coated stents, the first to hit the US market
since safety concerns scuttled their popularity two years ago.
The FDA said it cleared the company's Endeavor stent for use in
patients with clogged arteries. Medtronic said it expects to ship
100,000 units to hospitals in February.
Endeavor is one of a new generation of stents the industry hopes
can rejuvenate US demand for the drug-oozing devices, sales of
which plummeted to 2 billion US dollars last year, down from a peak
of 3.1 billion dollars in 2005.
Stents are tiny, mesh-wire tubes that prop open arteries after
they have been surgically cleared of fatty plaque. They became one
of the most lucrative medical devices in modern history after
companies began adding drug coatings to stents in 2003 to prevent
blood clotting. An estimated 6 million people worldwide have had
one implanted.
A series of studies in 2006 showed that months after they're
implanted, stent coatings have the potential to increase the risk
of life-threatening blood clots unless patients continue to take
anti-clotting drugs. Medical societies, such as the American
College of Cardiology, urge patients to continue taking the drugs
for at least a year after implantation.
In late 2006, a panel of federal advisers said that the majority
of patients with the drug-coated stents have an increased risk of
heart attack and death, though it's unclear whether their poor
health or the drug coatings are to blame.
The percentage of stent patients receiving drug-coated versions
versus the older, bare-metal models has fallen to an estimate 65
percent, from more than 80 percent, before 2006.
And there's been more bad news for companies that sell stents as
recently as last week. A study in the New England Journal of
Medicine showed patients who underwent bypass surgery had
fewer heart attacks than those who had stents implanted. The study
dimmed hopes that less intrusive stenting would prove just as safe
as surgery for people with clogged arteries.
(Agencies via Xinhua News Agency February 4, 2008)
