Cook Medical Inc. fielded CMS questions regarding two vascular devices for which the firm is seeking Medicare new-technology add-on payments during a Feb. 14 “town hall” meeting at CMS headquarters in Baltimore.

The Medicare agency is weighing evidence in support of add-on payments in fiscal 2013 for Cook’s Zilver PTX drug-eluting peripheral stent to treat symptomatic vascular disease in above-the-knee femoropopliteal arteries, as well as for the firm’s Zenith fenestrated endovascular graft for abdominal aortic aneurysm repair.

Zilver PTX is a self-expanding stent made of nitinol and coated with paclitaxel. During the CMS meeting, Cook outlined the results of its randomized trial comparing Zilver PTX treatment of restenotic lesions of the femoropopliteal artery of up to 14 centimeters in length versus standard-of-care angioplasty and provisional bare-metal stenting.

One-year results showed a 90.4% event-free survival rate, compared to 82.6% in patients randomized to standard angioplasty, and an 83.1% patency rate. At a meeting of FDA’s Circulatory System Devices panel last October, both the panel and FDA agreed that the trial met its primary safety and efficacy endpoints. (See Also see "Cook’s Zilver PTX Peripheral Drug-Eluting Stent Sails Through FDA Panel" - Medtech Insight, 17 October, 2011..)

“Zilver PTX demonstrates a substantial clinical improvement relative to previous technologies, including angioplasty, bare-metal stents and bypass surgery,” said Gary Ansel, director of the center for critical limb ischemia at Riverside Memorial Hospital in Columbus, Ohio, during the CMS hearing.

Still, the Medicare agency wanted to know whether the location of stent placement had any impact on outcomes, and whether there was enough data to make such a determination. But Ansel, co-principal investigator for Cook’s PMA trial, did not see any issues on those fronts.

“In having 1,000 patients, we saw no difference between any location as far as a recurring restenosis rate,” he said.

Cook anticipates FDA approval of the device prior to July 1 – the deadline for meeting eligibility requirements for the fiscal 2013 add-on payments. If FDA approves the device, it would be the first drug-eluting stent in the U.S. indicated to treat superficial femoral arteries. Current bare-metal stents on the U.S. market approved for use in femoral arteries are Bard’s LifeStent and W.L. Gore’s Viabahn.

To qualify for the special add-on payments, a product must meet several criteria. In addition to gaining FDA's nod by July 1 in the year preceding the payment, a product must be new enough that its technology is not yet reflected in the data that CMS uses to establish Medicare severity diagnosis related groups (MS-DRGs). It also needs to meet certain cost criteria, and its use must offer substantial clinical improvement over existing technologies and services available to Medicare patients.

During the town hall meeting for the applicants, Cook also addressed CMS questions regarding the Zenith implant, which is designed to treat abdominal aortic aneurysms in patients who are anatomically unsuitable for treatment with currently approved AAA endovascular grafts due to a short infra-renal neck.

Tara Mastracci, a vascular surgeon at the Cleveland Clinic and a consultant for Cook, said that the endovascular stent graft offers substantial clinical benefit as a repair option for patients with short infra-renal necks who would not have undergone surgery to treat AAA because of severe co-morbidities. The stent graft is intended as a less invasive treatment option compared to surgery.

CMS asked what type of evaluation of the renal arteries is typically done before implantation, and the extent to which there might be renal artery complications post-treatment.

Mastracci said that in her clinical trial experience, all patients were assessed with CT scans ahead of time. “We have a good idea of what the kidney arteries look like,” she said. And, “the risk of stenosis and ongoing renal problems is minimal.”

“We follow the patients yearly with duplex ultrasound,” she added. “We feel that we’re able to, with minimal radiation, follow these patients quite well.”

Mastracci noted that the device is currently under expedited review at FDA.

The Zilver PTX would be the first drug-eluting stent in the U.S. indicated to treat superficial femoral arteries.

Cook Medical

CardioMEMS Pulls Out, Again

While CardioMEMS Inc. also had applied for a fiscal 2013 add-on payment for its Champion HF implantable hemodynamic monitor system, CMS noted that the firm has withdrawn its application. The firm previously had withdrawn its application for a fiscal 2012 add-on payment. (See Also see "Vascular Device Firms Seek Medicare New-Tech Add-On Payments" - Medtech Insight, 9 January, 2012..)

In an interview with “The Gray Sheet,” the firm cited ongoing uncertainties surrounding the FDA approval timeline for the device – the same issue that caused the previous add-on payment application withdrawal.

At a December meeting, FDA’s Circulatory System Devices panel voted 6-4 that the benefits of the device, which monitors pulmonary artery hemodynamic data using a wireless sensor, do not outweigh the risks. (See Also see "CardioMEMS’ Heart Failure Monitor Foiled At Panel By FDA Inspection Findings Of Study Bias" - Medtech Insight, 12 December, 2011..) Industry watchers see the company as facing an uphill battle at best for approval.

Nevertheless, the company said it is continuing to work with FDA to answer the agency’s questions surrounding the device.

While LeMaitre Vascular also was among the firms to submit applications for fiscal 2013 add-on payments, for its UnBalloon non-occlusive modeling catheter, the device was not discussed at the CMS meeting.

During the town hall, however, AdvaMed renewed its call for CMS to revamp what the advocacy group feels are “overly restrictive” criteria for new-tech add-on payments. (See Also see "At CMS Town Hall, Firms Pitch New Tech's Impact On Reducing Hospital Stays" - Medtech Insight, 7 February, 2011..) CMS did not award any new-tech add-on payments last year. (See Also see "Denied! CMS Grants No New Inpatient New-Technology Add-On Payments For 2012" - Medtech Insight, 8 August, 2011..)

Cook Medical Makes Its Case For Medicare New-Tech Add-On Payments

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