Promise of Drug-Eluting Stents Confirmed

Originally Published MDDI November 2003

NEWSTRENDS

Erik Swain

Further cementing their status as a major medical breakthrough, drug-eluting stents have received favorable reviews from two third-party health-technology assessment organizations.

Hayes, Inc. (Lansdale, PA) and ECRI (Plymouth Meeting, PA) analyzed a variety of studies pertaining to sirolimus-eluting (SES) and paclitaxel-eluting stents (PES) and concluded they are likely to make a substantial impact on coronary care. The former, made by Johnson & Johnson (New Brunswick, NJ) entered the U.S. market this year. Two versions of the latter, made by Boston Scientific Corp. (Natick, MA) and Guidant Corp. (Indianapolis), are marketed in Europe and could receive FDA approval as soon as 2004. 

The Hayes report concludes that both stents are likely to greatly reduce incidences of restenosis (reblockage). Hayes said its analysis of published and unpublished data finds that the SES “significantly reduces the likelihood of reblockage of the artery, and consequently reduces the need for repeat coronary revascularization or other treatment, and improves event-free survival.” As for the PES, Hayes said, “early studies suggest [it confers] similar benefits.”

The Hayes report cautioned, however, that long-term safety and effectiveness are not yet proven, nor is the stents' efficacy in patients with very high risk of restenosis. 

It noted, however, that treatment with SES “appears to benefit some patients with risk factors for restenosis such as diabetes, long lesions, [and] lesions in small vessels.” 

Also favorable for SES, the Hayes report said, is that its use “led to significant increases in minimal lumen diameter and significant decreases in neointimal hyperplasia, percent diameter stenosis, and late loss of luminal area.” And it had an event-free survival rate of over 90%, compared to 70% for bare-metal stents. 

Hayes said treatment with PES shows “improved short-term outcomes compared with conventional stents, although the strength of the evidence… is weaker than that for SES.” Specifically, they reduce in-stent restenosis, late loss of luminal area, and the need for revascularization. They have a better rate of event-free survival than bare-metal stents. 

ECRI too found drug-eluting stents extremely promising but noted the need for long-term results. Its assessment concluded that drug-eluting stents reduce restenosis rates by as much as 64 times that of bare-metal stents. It said chances of restenosis from use of SES were 4 to 64 times less than that for bare-metal stents. For PES, chances of restenosis are about eight times less than for bare-metal stents. 

“It is possible that drug-eluting stents will replace bare-metal stents for all indications,” ECRI stated. “However, follow-up safety data reporting outcomes longer than a year are needed.”

In particular, it stated, more evidence is needed on how drug-eluting stents improve patient quality of life and whether they permanently alleviate angina symptoms.

The trials ECRI examined found no evidence of edge restenosis, persisting dissection, necrotic lesions, or thrombosis. They also found no difference in rates of death, myocardial infarction, and other complications between patients given drug-eluting stents and patients given bare-metal stents. 

But overall, ECRI said, there is “strong evidence” that both SES and PES “provide a significant benefit over bare-metal stents in appropriately selected patients."

Copyright ©2003 Medical Device & Diagnostic Industry