Boston Scientific Corporation, a worldwide developer, manufacturer and marketer of medical devices, has reported nine-month clinical endpoint data from its Orion trial, demonstrating excellent outcomes for the company's Epic Self-Expanding Nitinol Stent System in patients with iliac artery disease, a form of peripheral artery disease associated with severe leg pain caused by insufficient blood flow.

Results were presented by Daniel Clair, MD, FACS, principal investigator of the trial and chairman of the Department of Vascular Surgery, The Cleveland Clinic Foundation, at the International Symposium on Endovascular Therapy (ISET) in Miami.

“Peripheral stenting has become a recognized standard in the treatment of iliac arterial disease to restore blood flow in blocked leg arteries,” said Dr Clair. “Outcomes from the Orion trial support both the safety and efficacy of the Epic Stent and confirm its excellent performance in the treatment of atherosclerotic lesions in iliac arteries.”

The prospective, single-arm Orion trial enrolled 125 patients at 28 sites in the US. The trial met its primary endpoint, a composite rate of device- and/or procedure-related major adverse events (MAE) at nine months. MAE are defined as death within 30 days, myocardial infarction (MI, or heart attack) occurring during hospitalization, target vessel revascularization (TVR) through nine months and amputation of the treated limb through nine months.  The Epic Stent demonstrated a low nine-month MAE rate of 3.4 per cent in the intent-to-treat population, which was significantly lower than the pre-specified performance goal of 17 percent (p<0.001) based on historical published outcomes for iliac stenting. All reported major adverse events were related to TVR. No deaths through 30 days and no amputations through nine months were observed.

Patients experienced significant clinical improvement from baseline to nine months based on feedback from validated questionnaires evaluating walking distance, speed and stair climbing. An additional measure of effectiveness based on the Rutherford Classification showed improvement in the patient population from 7.2 per cent being asymptomatic or having mild claudication (class 0-1) at baseline to 82.3 per cent of patients at 30 days and 81.6 per cent at nine months. Duplex ultrasound showed a primary patency of 95.9 per cent, primary-assisted patency of 96.7 per cent and secondary patency of 98.3 per cent, indicating that treated lesions remained open through the nine-month follow-up period.

“We are pleased to report positive outcomes for US patients in the Orion clinical trial. The Epic Stent has been used successfully in Europe for several years and we look forward to offering the device to US physicians upon FDA approval,” said Jeff Mirviss, president of Boston Scientific's Peripheral Interventions business. “The Epic Stent is a novel stent platform designed to offer both acute and clinical advantages over older-generation stent systems.  Upon approval, the Epic Stent along with the market-leading Express LD balloon-expandable iliac stent, would enable Boston Scientific to offer a complete line of advanced iliac solutions for physicians and patients.”

The Epic Stent is a self-expanding nitinol stent designed to sustain vessel patency, while providing enhanced visibility and accuracy during placement.  It employs an innovative Tandem Architecture, which is engineered to provide excellent stent flexibility while maintaining predictable radial force characteristics across the entire stent size matrix. The Epic Stent is compatible with 6F sheaths, and the stent delivery system is compatible with 0.035 inch guidewires.

Orion clinical data is being used to support application for US Food and Drug Administration (FDA) approval of the Epic Stent system, which was submitted to the FDA in September 2011. The Epic Nitinol Stent System received CE Mark approval and was launched in Europe and other international markets in 2009. In the US, it is an investigational device, limited by applicable law to investigational use only and not available for sale.