The results of two large clinical trials using drug-coated stents were presented last week at the Transcatheter Cardiovascular Therapeutics 2002 scientific sessions on Washington D.C. Both confirmed and extended results from earlier trials using drug-coated stents. That is, with drug-coated stents the risk of restenosis (the largest remaining problem with the use of stents in coronary arteries) appears to be dramatically reduced. (Click here for a quick review of the problem of restenosis.)
The first of the two trials, the SIRIUS trial, examined the use of the sirolimus-coated stent, from Cordis and Johnson & Johnson. Previous trials with the sirolimus-coated stent suggested a remarkable reduction in restenosis compared to using "bare" metal stents. However, the earlier trials were largely limited to patients whose coronary artery blockages were considered nearly ideal for the use of stents. In the SIRIUS trial, in contrast, patients were intentionally enrolled whose blockages were considered high-risk. Despite this higher risk population of patients, the SIRIUS trial showed a pronounced reduction in the rate of restenosis among patients receiving the sirolimus-coated stents. Patients receiving the drug-coated stent had a 91% reduction in restenosis within the stent itself. The main endpoint of the study, however, was not restenosis but "target vessel failure" defined as cardiac death, heart attack, or the need for revascularization within 9 months of stent placement. The drug-coated stents reduced target vessel failure from 21% to 8.6%.
In the second trial, TAXUS II, results with a paclitaxel-coated stent from Boston Scientific were presented. Overall results were comparable to those achieved with the sirolimus-coated stents. (In TAXUX II, most patients did not have high-risk coronary artery blockages. Ongoing trials with the paclitaxel-coated stents are enrolling high-risk patients.)
In summary, at least two types of drug-coated stents continue to yield remarkable decreases in the rate of restenosis when compared to standard, bare-metal stents. It is increasingly likely that, once these stents are approved by the FDA for use in the United States (expected to happen some time in 2003), they will revolutionize the treatment of coronary artery disease.
While cardiologists are extremely anxious to get their hands on this remarkable technology, the cost of these new stents (expected to cost approximately $3000 apiece compared to approximately $1000 for standard stents) will stress the budgets of many hospitals and create new stress for insurers.
