The US Food and Drug Administration (FDA) has approved the EverFlex Self-Expanding Peripheral Stent System (Covidien) for use in the superficial femoral artery and/or the proximal popliteal artery. The EverFlex system, which has been approved for peripheral indication in international markets since 2006, is now available in the United States, including a 200mm stent length.
The clinical data supporting the FDA approval of the EverFlex system for use in the peripheral vasculature was obtained through the DURABILITY II investigational device exemption trial that enrolled patients at clinical sites within the US and Europe. DURABILITY II is the first clinical study to evaluate lesions up to 18cm and to specifically test the performance of a single long, up to 200mm stent, in the superficial femoral artery and the proximal popliteal artery.
Specifically, the study results show no major adverse events at 30 days and a low one-year stent fracture rate of 0.4%. Additionally, primary patency at one year was 67.7% when analysed by simple proportions of patients patent; using Kaplan-Meier time-to-event analysis, it was 77.2%.
“DURABILITY II is a landmark trial intended to study the patency and fracture resistance of placing a single nitinol stent in the superficial femoral artery. It provided the clinical evidence necessary to demonstrate that you can successfully treat long, complex lesions in the superficial femoral artery with the EverFlex,” said Krishna Rocha-Singh, director, Prairie Vascular Institute, Springfield, Illinois, USA, and co-national principal investigator of DURABILITY II.
Until now, physicians often addressed longer lesions by overlapping multiple stents. Overlapping stents have a higher propensity to fracture, thereby increasing the potential for restenosis to occur. Being able to place one long stent, versus multiple shorter stents, may lead to better long term clinical performance.