Conor Medsystems, Inc., a developer of innovative controlled vascular drug delivery technologies, has announced that the first patient had been enrolled in the company's COSTAR II US pivotal clinical trial.

The COSTAR II trial (CObalt chromium STent with Antiproliferative for Restenosis) is designed to randomize approximately 1,700 patients at up to 75 US sites and 15 international sites. Conor expects the data from this trial to support its application for US regulatory approval of Conor's CoStar cobalt chromium paclitaxel-eluting stent.

Dean J. Kereiakes, Medical Director of The Heart Centre of Greater Cincinnati said, "This study will be of particular interest to the interventional cardiologist community because the trial will include patients with multi-vessel disease which more closely represent the real-world population. There is limited data available on the use of drug-eluting stents in multi-vessel disease, so data from this trial will be especially meaningful to clinicians who are looking for the best technologies to treat patients with complex coronary artery disease. In addition, the design of Conor's CoStar stent appears to have several potential advantages as compared to conventional drug eluting stents, including a low profile for ease of navigation and placement in smaller vessels, the ability to control the release kinetics of the drug, and the use of a bioresorbable polymer that leaves no residual polymer or drug on the stent."

The COSTAR II trial is a randomized, single-blind, non-inferiority study comparing Conor's CoStar stent with Boston Scientific's TAXUS Express2 drug-eluting stent in the treatment of de novo lesions in patients with single or multi-vessel coronary artery disease. The CoStar stent is loaded with a dose of 10 mcg of paclitaxel per 17 mm stent using a bioresorbable polymer, a formulation determined to be efficacious during the company's European clinical studies.

The primary endpoint for the study will be major adverse cardiac events (MACE) at eight months, defined as a composite of target vessel revascularization (TVR), myocardial infarction and cardiac-related death. Other endpoints include target lesion revascularization (TLR), binary restenosis and in-segment and in-stent late loss as measured by angiography. The trial will include a continued access registry for direct stenting.