US Enrollment Begins in OSPREY Study of Terumo's Misago SFA Stent

September 13, 2010—Terumo Interventional Systems (Somerset, NJ) announced the first United States patient implant in the OSPREY (Occlusive/Stenotic Peripheral Artery Revascularization Study) trial, which will evaluate the safety and efficacy of the company's Misago peripheral self-expanding stent system for use in the superficial femoral artery (SFA).

According to the company, the OSPREY clinical trial will simultaneously enroll patients in the United States and Japan as a part of the Medical Device Collaborative Consultation and Review of Premarketing Applications program under the larger Harmonization By Doing initiative. The OSPREY trial was selected as one of two projects to pilot this approach, which is intended to shorten the gap between product approvals in these two markets. The pilot program is a cooperative effort led by the US Food & Drug Administration and the Japanese Ministry of Health, Labour and Welfare's Pharmaceuticals and Medical Devices Agency.

In the United States, OSPREY is a single-arm, multicenter, nonrandomized, prospective clinical trial studying the treatment of atherosclerotic stenoses and occlusions of the SFA. The primary endpoints are the primary stent patency rate at 1 year as confirmed by duplex ultrasound or angiography and freedom from major adverse events within 30 days of the procedure resulting in target lesion revascularization, amputation of the treated limb, or death.

The study will include up to 350 patients: a maximum of 250 patients in up to 30 centers in the United States and 100 patients in Japan. Japan received regulatory approval to begin the trial last year and has already started to enroll patients. In Japan, there are two arms of the study: 50 patients receiving the Misago stent system and 50 patients receiving percutaneous transluminal angioplasty.

The Misago peripheral self-expanding stent system consists of a nitinol stent that is premounted on the distal portion of a rapid-exchange delivery catheter system. The stent has three radiopaque markers located on each end of the stent to help ensure accurate placement in the lesion. The design distributes the dynamic SFA stress loads throughout the stent's struts providing flexibility and durability against bending, compression, and torsion, the company stated.