Cook (Bloomington, Indiana) yesterday reported that it is preparing to file with the FDA to move forward with a pivotal study of its Zenith Fenestrated Endograft for the treatment of complex abdominal aortic aneurysm (AAA), and will bolster its filing with report of the 1,000th procedure for implantation of the device.

“We are currently in the situation of putting together, and should submit our information to the FDA in the next two weeks,“ seeking the go-ahead for that trial, Barry Thomas, global leader of Cook's endovascular therapy products division, told

Medical Device Daily.

Thomas said that the 1,000-implant milestone provides “a level of credibility“ and “a comfort level“ that extends its previous clinical experience and journal reports validating the device. Overall, that accumulation of experience says “Yes, we can do this as a company – [the device] provides good outcomes on a global basis,“ he said.

The fenestrated graft is unique in the way it is made, with a particular approach to construction that is needed to fit the application for treating difficult aneurysms, Thomas said.

The treating physician uses a variety of imaging techniques to describe the anatomy of the aneurysm. This description is then sent to Cook's Australian facility that creates the stent endograft, which is “manually put together and manually made,“ he said, noting that Cook is the only company doing this.

The specific, customized design is needed for the difficult, short “necks“ of the diseased anatomy “between the bottom margin of the renal artery and the top margin of the expansion of the aneurysm.“ These shorter necks, he said, are found in “a particular range of patients“ who can't be treated with standard AAA grafts, which are susceptible to endoleaks.

Cook says the fenestrated endograft is the first in the world to incorporate tailored openings – either as semi-circular scallops or full-circular openings called fenestrations – in the top section of the endograft. This allows the self-expanding fabric-covered stent-graft to treat aortic and aortoiliac aneurysms extending close to the renal and superior mesenteric arteries. These are then stented to reduce the risk of restricting or blocking critical blood flow to the kidneys and bowel – the problem endoleaks.

Thomas said that assuming FDA approval to move forward with the pivotal trial, the company expects to launch the trial in August. The device already has regulatory approval for sale in Canada, Europe, Australia – the country where it was initially developed – New Zealand and other major markets.

Thomas said that Cook alsois moving forward with a few implantations of its device to treat thoracic aneurysms, which he called “not a huge business market,“ but extremely important for those with this type of aneurysm.

The 1,000th implantation of the fenestrated device was performed at the University of California San Francisco , by a team led by vascular surgeon Timothy Chuter, MD, and Darren Schneider, MD, vascular surgeon and interventional radiologist.

They have also been carried out at the Cleveland Clinic (Cleveland), where Roy Greenberg, MD, director of endovascular research, said, “The patient outcomes we've experienced using Cook's fenestrated endograft have enabled us to treat a wider range of patients.“

Greenberg has coordinated a number of national and international investigational trials designed to evaluate endovascular devices, particularly those associated with the repair of thoracic and abdominal aortic aneurysms.

As a matter of complete disclosure, Cook noted that Greenberg receives royalties from the company related to intellectual property he developed. He is also a paid consultant for Cook.

Cook, in conjunction with a number of vascular surgeons discussed the global results of the first 1,000 fenestrated endograft cases at the 28th Annual Charing Cross Symposium in London on April 10. Krassi Ivancev, MD, highlighted the outcomes of the procedures conducted with the Zenith Fenestrated Endograft.

The fenestrated device builds on and is a next-generation form of the company's Zenith Flex AAA Endovascular Graft, for which it received FDA approval in 2004 (MDD, June 8, 2004), along with the delivery system, the H&L-B One Shot Introduction System. The company has termed the Flex graft “the only hand-made device with a wide array of components and sizes.“