A Medical Device Daily

Conor Medsystems (Menlo Park, California), a developer of what it terms “controlled vascular drug delivery technologies,” reported at the EuroPCR (Paris Course on Revascularization) meeting in Paris positive 12-month follow-up clinical data from a pivotal trial of its CoStar stent.

The clinical results were presented yesterday by Keith Dawkins, MD, director of cardiac interventions at Southampton University Hospital (Southampton, UK), who said the findings for the 12-month period “include low incidence of target lesion revascularization and major adverse cardiac events. With its low profile and high radiopacity, the CoStar stent is highly deliverable and permits direct stenting even in narrow and tortuous vasculature.”

He noted also that use of bioresorbable polymers in the stent “ensures that no permanent polymer residue or drug remains at the target site.”

Dawkins and Antonio Colombo, MD, director of the cardiac catheterization laboratory at Emo Centro Cuore Columbus (Milan, Italy), are principal investigators for the trial.

A total of 176 lesions were treated in 145 patients using the CoStar stent, formulated to release a therapeutic dose of 10 mcg of paclitaxel per 17 mm stent over about 30 days. Complex characteristics of the patient group include an average vessel diameter of 2.62 mm and multi-vessel disease in more than 50% of patients. About 52% of the lesions were treated by direct stenting.

At 12-month follow-up, the target lesion revascularization (TLR) rate was 2.9%, and the rate of cumulative major adverse cardiac events (MACE) was 7.6%. There were no reported cases of stent thrombosis between the cessation of anti-platelet therapy at six months and 12-month follow-up.

“We are very pleased with the consistent clinical results for the CoStar stent, which after 12 months continues to demonstrate a positive safety and efficacy profile,” said Frank Litvack, MD, chairman and CEO of Conor. “A low-dose, long-release formulation of paclitaxel proved to be efficacious over the long-term, reinforcing our earlier positive clinical findings.”

EUROpean cobalt chromium STent with Antiproliferative for Restenosis (EuroSTAR) is a prospective, multi-center, sequentially enrolled, non-randomized, two-arm dose-ranging pivotal study evaluating the safety and performance of the CoStar stent for the treatment of restenosis.

The study sequentially enrolled patients from 18 European centers into one of two registry arms with two different dose formulations of paclitaxel. The 12-month follow-up data reflects the first arm of the study, which evaluated the clinical performance of a 10 mcg dose formulation per 17 mm stent released over about 30 days among 145 patients. The second arm of the study, employing a 30 mcg dose released over around 30 days, completed enrollment in March.

In contrast to surface-coated stents, Conor’s stents are designed for vascular drug delivery. Its CoStar cobalt chromium paclitaxel-eluting stent incorporates hundreds of small holes, each one a reservoir into which drug/polymer compositions can be loaded. The CoStar also uses bioresorbable polymers that are absorbed by the body after the drug is released, leaving no permanent residual polymers at the target site.

Data from Conor’s EuroSTAR trial was used to support the company’s CE mark application filed earlier this year. The company said it anticipates receiving CE-marking of the CoStar stent in late 2005. Pending regulatory approval, the CoStar stent will be marketed in Europe, Latin America and parts of Asia by one of the company’s distributors. In March, a limited market release of the CoStar stent began in India through Conor’s South Asia distribution partner.

In the U.S. the CoStar stent is an investigational device limited by law to investigational use.