Small German trial could be a breakthrough treatment in vascular disease
WEDNESDAY, Feb. 13 (HealthDay News) -- Drug-coated stents haven't worked well for blocked leg arteries, but German doctors are reporting good initial results with drug-coated balloons, which are inserted at the end of catheters and are inflated to reopen the arteries.
Catheters whose balloons were coated with paclitaxel, one of the drugs commonly used for coronary artery stents, were better at keeping leg arteries open than conventional balloon catheters, said the study by researchers at the Eberhard-Karls University in Tuebingen.
Only two of the 48 persons with what is formally known as peripheral artery disease (PAD) who were treated with the coated balloons required second procedures to reopen arteries in the following six months, compared to 20 of the 54 people treated with conventional catheters, the report said.
The difference was evident after two years, when 28 of the 54 people treated with conventional balloons required reopening procedures, compared to seven of the 48 patients treated with coated catheters. Over that period, the drug-treated arteries remained more open than those treated with conventional devices.
No benefit was seen in a third group of patients who were treated with conventional catheters and had paclitaxel dripped into their arteries.
The average age of the study participants was 68; 24 percent were smokers, and 49 percent had diabetes.
The findings are published in the Feb. 14 issue of the New England Journal of Medicine.
"This is a really promising initial look at this technology," said Dr. Daniel Clair, chair of vascular surgery at the Cleveland Clinic. "It is very promising, but we need more data."
Drug-coated stents are not used routinely in the United States for PAD, Clair said. Two trials for PAD done in Europe showed initial advantages of drug-coated stents over the bare-metal kind, he said, but the differences had disappeared after two years, and a number of the stents implanted in leg arteries had fractured, he said.
Several aspects of the German trial raise questions, Clair added. The blockages treated in the study were relatively small, averaging 7.5 centimeters (about 3 inches), Clair noted, while the femoral artery, which is most often affected by PAD, is about 16 inches long.
"I would love to see this kind of trial done in the United States with longer lesions," Clair said.
That thought was echoed by Dr. Issam Moussa, director of endovascular services at New York Presbyterian/Weill Cornell Medical Center in New York City.
"This is obviously very promising, but my initial impression is that this is too good to be true," Moussa said. Drug-coated balloons have been tried for coronary arteries without success, he said, "because not much of the drug goes into the artery wall. My skepticism comes from that biological aspect."
But that view is balanced by "kind of an optimistic perspective," Moussa said. "If this [the German finding] really works, it would be a really big breakthrough. We should design a really big trial with hundreds of patients and more complicated lesions using this device to see if we can replicate the German results."
The German researchers got financial support for their study from a number of drug companies, including stent manufacturers.
For more on PAD, consult the U.S. National Library of Medicine.
SOURCES: Daniel Clair, M.D., chair of vascular surgery, Cleveland Clinic; Issam Moussa, M.D., director of endovascular services, New York Presbyterian/Weill Cornell Medical Center, New York City; Feb. 14, 2008, New England Journal of Medicine
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