CDU at Transcatheter Cardiovascular Therapeutics 2002: Drug-coated stents dominate, but other technologies edge onto stage.

CDU at Transcatheter Cardiovascular Therapeutics 2002

Drug-coated stents dominate, but other technologies edge onto stage

By KEVIN NEW, CDU Washington Editor

and LARRY HAIMOVITCH, CDU Contributing Editor

WASHINGTON Much like the real estate mantra about location, drug-eluting stents grabbed the lions share of attention during the late-September Transcatheter Cardiovascular Therapeutics 2002 conference at the Washington Convention Center. While it isnt unusual for medical meetings to have a buzz about them for some new technology or technique, to have one dominate thought and talk to the extent that drug-coated stents did at this years TCT gathering was at least a bit out of the ordinary.

The meeting featured reports of clinical trials featuring coated stents from sector leader Cordis/ J&J (Miami Lakes, Florida), as well as from pursuers Boston Scientific (Natick, Massachusetts) and Guidant (Indianapolis, Indiana). Also featured were interesting sessions on the regulatory environment for these attention-getting devices, as well as a spirited debate as to whether they represent a revolutionary step in medicine or a case of misguided hysteria. Almost every program entry that had the words drug coated and stent attached guaranteed an overflow audience, many numbering in the thousands.

And, lest one think that TCT was totally stent-centric, the five-day program featured numerous worthwhile presentations on other technologies, including stroke prevention, which is attracting growing attention among clinicians. New imaging technologies for cardiology were another point of interest.

In the first overflow session at this year's gathering, TCT impresario Martin Leon, MD, co-principal investigator of the SIRIUS trial conducted by Cordis, a business of Johnson & Johnson (New Brunswick, New Jersey), said that drug-eluting stents that are longer even as little as 10 mm in additional length offer higher success in battling restenosis in patients with de novo, or previously untreated, coronary lesions. The longer the stent, the better the restenosis rates are. We found that for every 10 mm of added stent, we gained an additional 13% [in reduction] of restenosis, Leon said.

The therapeutic importance of that longer length in conjunction with a drug was the main message he delivered. Perhaps one of the most anticipated clinical trials of the year, the SIRIUS results elevated the hubbub surrounding drug-coated stents, which are set to come on-line commercially next year, with Cordis clearly poised to lead the field out of the sales gate.

The SIRIUS trial showed minimal in-stent lumen loss. The 3.2% rate of angiographic in-stent restenosis represents a 91% reduction vs. the metal stent, Leon said.

Those results will lead to considerable changes in the treatment of cardiovascular disease, said Eric Topol, MD, of the Cleveland Clinic Foundation (Cleveland, Ohio), and also the moderator of the opening Late-Breaking Clinical Trials session.

The SIRIUS trial was purposely created with high-risk patients in mind to tout the superior advantages of drug-coated stents vs. bare metal stents, said Leon, director and CEO of the Cardiovascular Research Foundation (New York), which also is the organizer of the annual TCT conference. A majority of patients were at risk of restenosis. About 26% of the patients also had diabetes. Additional risk factors of patients included longer lesions with an average of 14.4 mm, hyperlipidemia and hypertension. Some patients also had undergone percutaneous coronary procedures or coronary artery bypass.

About 27% of the study patients had lesions requiring placing two overlapping stents, which led the researchers to their findings. We used an average of 1.4 stents per patient, Leon said. Furthermore, the device shows promising safety results as well. A nine-month follow-up demonstrated an event-free survival rate of 92.7% vs. 80.7% of patients with metal stents. Also at nine months, patients had a 75% reduction in target lesion revascularization rates.

In another report, Jeffrey Moses, MD, co-principal investigator and a faculty member with the Cardiovascular Research Foundation at Lenox Hill Heart and Vascular Institute (New York), presented results from a randomized, double-blind controlled clinical trial involving 53 treatment centers in the U.S. A total of 1,058 patients were involved: one group received the drug-eluting stent while the others received a bare metal coronary stent.

The findings are very positive and consistent with results of earlier studies, Moses said. There are no significant differences between our earlier data and our final data. There were no issues associated with safety, he reported via satellite hookup from his facility in New York. Sirolimus, or cytostatic drugs, work differently than their cell-killing counterparts. Sirolimus inhibits cell proliferation by preventing their multiplication. This trial the Randomized Study with the Sirolimus-eluting Velocity Balloon-Expandable Stent ended this past spring.

Boston Scientific (BSC) was the second big-gun stent manufacturer to release highly anticipated data, reporting on its TAXUS II clinical trial during another late-breaking clinical trials session. Boston Scis data showed impressive results at treating cardiac patients facing the more invasive bypass surgery currently used to treat them. The companys Express stent uses a polymer carrier and releases the anti-coagulant paclitaxel, which is marketed under the brand name Taxol.

There was a net volume obstruction reduction of 70% in the first cohort of patients, which is truly impressive, Antonio …