Aneurysm Sealing Device Hits Hurdles

— Migration, endoleaks, and aneurysm growth cited for novel Nellix device

MedicalToday

WASHINGTON -- The Nellix endovascular aneurysm sealing (EVAS) device that relines a failed stent graft might see a delay on its way to the U.S. market.

At the same time as European researchers reported rosy results last week -- 100% technical success for 15 consecutive patients with failed endovascular aneurysm repair (EVAR) of an abdominal aortic aneurysm when Nellix was used, typically in combination with chimney procedures -- manufacturer Endologix was sending out a "Dear Doctor" letter that told a different story.

"During our on-going post-market surveillance and review of results from clinical studies, we recently observed that some patients with specific aortic anatomies experienced device migration, endoleaks and/or aneurysm enlargement," the letter said.

The device was intended to seal the aneurysm sac with fewer endoleaks or device migrations than other available endovascular options.

For the European market, where the device was cleared for use in 2013, the company said it would update the Nellix indications for use, although exactly what those changes would be were not spelled out in the letter that went to at least some clinicians on Oct. 28, nor on the company's website as of Nov. 1.

But the company did reaffirm its "plan to continue developing the Nellix platform and gradually broadening indications to include the treatment of patients with juxtarenal and pararenal aneurysms. We are also developing a next generation version of EVAS which will provide improved treatment options for patients with abdominal or thoracic aortic disease."

While the news appeared to be percolating slowly among interventional cardiologists and vascular surgeons at the Transcatheter Cardiovascular Therapeutics meeting here, , of Lankenau Heart Institute in Wynnewood, Pa., said he had seen the letter.

"I don't want to read into it too deeply but my sense is the early experience [device] needs modification," he said.

Endologix had filed for FDA approval and initially projected a response in late 2016 or early 2017, but then an and the company's forecast for potential approval was pushed back to fall 2017. A redesign would probably mean yet another setback.

However, , medical director of Miami Cardiac & Vascular Institute, who has been involved with U.S. study of the Nellix device, didn't think approval would have to wait for a next-generation device nor would the new information mean delay in the process.

"From the information shared with us [investigators], there is a subset of patients with this very large clot burden in the aneurysm, and as a result a very narrow flow channel," he said in an interview. "That kind of patient may not be ideal for this kind of device.... From what I understand... that was the characteristic of the patient in which migration occurred."