DURABILITY II 1-Year Data Presented for Covidien's EverFlex Stent to Treat SFA Disease

January 24, 2012—Covidien (Mansfield, MA) announced that Co-National Principal Investigator Jon Matsumura, MD, presented 1-year results from the DURABILITY II study of the company's EverFlex stent at the International Symposium on Endovascular Therapy in Miami Beach, Florida.

According to Covidien, the DURABILITY II clinical study evaluated the safety and efficacy of using a single EverFlex self-expanding stent up to 20 cm in length to treat atherosclerotic disease of the superficial femoral (SFA) and proximal popliteal arteries. The EverFlex stent system is designed to enable single stent placement in long lesions in peripheral arterial disease (PAD) patients, with the intention of eliminating the need for overlapping two short stents, thereby reducing the possibility of stent fracture.

DURABILITY II enrolled 287 patients with lesions up to 18 cm in length at 44 investigational sites in the United States and Europe. The study's primary endpoints were 30-day major adverse events and primary patency at 1 year compared to performance goals published by VIVA Physicians Inc. (VPI).

Dr. Matsumura reported that the mean age of the patients was 68 years, and 66% of the patients were men. Prominent comorbidities included hypertension (88%), hyperlipidemia (86%), and diabetes (43%). The mean lesion length as measured by core laboratory was 89.1 mm. The mean normal-to-normal lesion length measured by investigational sites was 109.6 mm.

The DURABILITY II investigators found that no major adverse events occurred at 30 days. The primary patency rate at 1 year was 67.7% when analyzed by simple proportions of patients patent; it was 77.2% when using Kaplan-Meier time-to-event analysis. The results met predetermined VPI performance goals for safety and effectiveness and showed a 1-year stent fracture rate of 0.4%.

“In another new chapter of minimally invasive treatment of PAD, DURABILITY II evaluated a novel longer stent system that offers the option of single stent treatment of extensive symptomatic femoral artery disease,” commented Dr. Matsumura. “The results are impressive.”

Covidien noted that the results from this investigational device exemption study are included in the company's premarket approval application for the EverFlex stent system, which is currently under review by the US Food and Drug Administration.