Medical Device Daily

Which is more important — clinical trial data rolled out at a major medical meeting or publication of that data in a prestigious journal?

Whatever the answer, Cordis (Miami Lakes, Florida) is hoping that both means of clinical data dissemination will support improved penetration for its Cypher drug-eluting stent (DES) in that fast-growing market.

And — also — whatever the answer, both the Cypher DES and the Taxus DES from Boston Scientific (Natick, Massachusetts) will benefit from the most recent report on this technology in this week's issue of the Journal of the American Medical Association (JAMA). That report continues validation of DES technology in the mano a mano competition vs. angioplasty, in this case for treating restenosis at a previously stented segment of a coronary vessel.

Additionally, a somewhat larger plaudit was bestowed by the study on the Cypher DES for use in treating “high-risk“ groups.

“This is information that we have seen before,“ said Brian Firth, MD, vice president of medical affairs and health economics, worldwide, for Cordis, a unit of Johnson & Johnson (J&J; New Brunswick, New Jersey). He acknowledged that the study data already has been presented, both at last year's meeting of the European Society of Cardiology and the annual Transcatheter Catheter Therapeutics meeting. But the results and conclusions from such studies should receive perhaps even more consideration “at another level when you get something published in a very prestigious peer-reviewed journal,“ Firth told Medical Device Daily.

The study, “Sirolimus-Eluting Stent or Paclitaxel-eluting Stent vs. Balloon Angioplasty for Prevention of Recurrences in Patients with Coronary In-Stent Restenosis,“ reported that both the sirolimus-eluting DES (the Cypher) and the paclitaxel-eluting stent (the Taxus) were superior to conventional balloon angioplasty for reducing the recurrence of restenosis (called in-stent restenosis) in a trial of 300 patients divided evenly into three groups.

The researchers noted that a variety of studies had demonstrated the reduction of restenosis used as a primary treatment “below the limit of 10%“ and that the two DES types were of “equivalent efficacy for treatment of de novo lesions.“ But they noted also that there had not been head-to-head trials comparing these DES devices to “plain angioplasty“ in unblocking restenosis following primary stenting, with angioplasty in this treatment “disappointing with a recurrence rate above 40%.“

To explore the potential differences, the study groups consisted of patients with 50% renarrowing of a segment of coronary vessels treated with non-DES stents. These patients additionally had presented with angina pectoris and/or a positive stress test.

For the primary trial endpoint, the incidence of angiographic restenosis (of 275 of the patients) was 44.6% (41 of 92) in the balloon angioplasty group; 14.3% (13 of 91) in the sirolimus stent group (P < .001 vs. balloon angioplasty); and 21.7% (20 of 92) in the paclitaxel stent group (P = .001 vs. balloon angioplasty).

The incidence of target vessel revascularization was 33% (33 of 100) in the balloon angioplasty group; 8% (8 of 100) in the sirolimus stent group (P < .001 vs. balloon angioplasty); and 19% (19 of 100) in the paclitaxel stent group (P = .02 vs. balloon angioplasty). There was no increased risk of late total occlusion with the DES products.

More important for Firth was the finding of the study's secondary endpoint: the assessment of the two DES products in the prevention of recurring restenosis.

Here, the prize appeared to go to the Cordis product — though with some heavy qualifiers attached.

The results “suggest that in this high-risk subset of patients, [the Cypher] sirolimus-eluting stents may be [italics added] superior to [Taxus] paclitaxel-eluting stents,“ according to the researchers.

The paper indicated that both “previous publications“ and future uses of the two stents in treating “lesions with a particularly high risk for restenosis such as restenotic lesions“ are likely to further clarify the differences between the two DES products.

“With simple lesions, you may not be able to see differences between [the two] products,“ Firth said, adding his view that the Cypher will more likely be found superior for use in treating “a lot of patients who fall into the various categories of more complex, later-risk restenosis.“

Firth acknowledged that the Cypher is trailing significantly in the U.S. drug-eluting stent race behind Boston Sci's Taxus, which claims the lion's share of the market at about 70%.

He attributed this differential largely to product launch difficulties suffered by Cordis, primarily in supplying enough inventory to keep pace with the heavy initial demand, but that “that has changed — we have taken major steps to increase our supply.“

And he said that the Cypher maintains an overall share of “greater than 50%“ outside the U.S.

Firth noted the proliferation of studies focused on the use of approved and in-the-pipeline DES devices, calling this “quite extraordinary, given the product hasn't been on the market quite three years — this is probably the most-documented new medical device ever.“

He said that Cordis currently has 40 to 50 studies ongoing “in-house,“ while a multitude of other independent studies are looking at a number of drug-eluting stent products.

Referring to the JAMA study, Firth emphasized that the study it was not sponsored by Cordis and added that independence “adds a lot of credibility“ to the conclusions reported from it.

One conclusion the report did not reach was concerning the use of brachytherapy for treating in-stent restenosis.

While at least one recent report has cast doubt on the use of brachytherapy as a primary method for unblocking clogged arteries (MDD, Sept. 30, 2004), authors of the new JAMA study note that no brachytherapy group was included in their research design and that this “should be acknowledged as a limitation.“

They added that “the definitive answer regarding the optimal treatment of in-stent restenosis will come after the completion of ongoing trials that include both brachytherapy and drug-eluting stent arms.“

Adnan Kastrati, MD, was principal investigator of the study. Primary funding support for the study was provided by the German cardiology center Deutsches Herzzentrum (Munich).