Off-label use of drug-coated stents appears widespread

U.S. physicians commonly use drug-coated stents to treat coronary artery blockage in ways not approved by the FDA, according to research published in the May 9 issue of the Journal of the American Medical Association. This off-label and untested usage may contribute to ischemic complication rates.

About half of all drug-eluting stent usage involves off-label or untested settings, according to lead author Dr. Nirat Beohar, an assistant professor of cardiology at Northwestern University Feinberg School of Medicine. Of 5541 patients found to receive drug-eluting stents in the multicenter study, 2588 (47%) received stents for off-label or untested indications.

"Compared with patients receiving drug-eluting stents for standard indications, those receiving such stents for off-label and untested indications tended to present with more severe clinical profiles, which would have excluded these patients from the pivotal randomized trials that led to FDA approval of drug-eluting stents," Beohar and colleagues wrote in JAMA. "Both observed and adjusted analyses indicated a greater than twofold higher risk of death, myocardial infarction, or stent thrombosis."

Beohar and colleagues analyzed data on 7752 patients who underwent percutaneous coronary intervention (PCI) between January and June 2005 to determine the frequency, safety, and efficacy of drug-eluting stents for off-label and untested indications. Off-label indications included restenosis, bypass graft lesion, and long lesions. Untested indications included left main, ostial, bifurcation, or total occlusion lesions.

"Compared with standard use, short-term outcomes appear to be worse with off-label and untested use," the investigators said. "However, even with off-label or untested use of drug-eluting stents, overall absolute event rates both in hospital and at 12 months following PCI remain relatively low."

Elaborating on the findings in the same JAMA issue, researchers at Baylor College of Medicine reported that off-label use of drug-eluting stents is more common than on-label use and is associated with a persistently higher rate of adverse angiographic and clinical outcomes.

The researchers analyzed data from 3323 patients, learning that 1817 (54%) had at least one off-label application. Although the off-label group experienced a higher frequency of adverse effects, including heart attack, there was no difference in the death rate between the two groups after one year.