From the May 7, 2007, issue of "The Gray Sheet"
CMS has reversed its earlier proposal to significantly expand coverage of carotid stenting, dampening industry's hopes for a more open U.S. carotid stent market in the near term.
The April 30 decision essentially maintains a 2005 policy that covers carotid stenting in patients for whom the "gold standard" endarterectomy surgery is too risky and who have symptomatic blockage >70% in their neck arteries. CMS covers high-risk symptomatic patients with between 50% and 70% blockage and asymptomatic patients with >80% blockage only in FDA-approved studies.
Following a March 2006 request from Guidant to more closely align Medicare coverage with the devices' FDA indications, in February CMS proposed to extend unrestricted carotid stenting coverage to high-risk, asymptomatic patients with blockage >80%. That policy would have doubled the population covered for the procedure, according to industry.
However, in finalizing its decision this week, CMS rescinded the planned revision. Upon reevaluation of available evidence, "we now believe that our proposed decision to remove the added safety and patient protection components of clinical trials and post approved studies was premature," the agency writes.
"This is a disappointing decision for patients who don't have symptoms for stroke and are at high risk for surgery," Abbott spokesperson Karin Bauer Aranaz said. Abbott markets the Xact carotid stent as well as the Acculink stent system, which it acquired when it bought Guidant's vascular business in April 2006.
Johnson & Johnson/Cordis (Precise), Boston Scientific (NexStent) and ev3 (Protégé) also market carotid stents in the United States. New FDA approvals expected in 2007 include Boston Scientific's Carotid WallStent Monorail and Medtronic's Exponent.
Agency Cites BlueCross BlueShield Assessment
CMS' reversal is in part based on a recent assessment from the BlueCross BlueShield Association's Technology Evaluation Center (TEC) which concludes there is not sufficient evidence to support the overall health benefit of stenting the carotid arteries to reduce stroke risk in an expanded patient population. TEC's assessment was finalized in February and is pending public release.
TEC cites American Heart Association guidelines that suggest stenting must have a perioperative morbidity and mortality rate of less than 3% to be considered a beneficial alternative to surgery in asymptomatic patients. Thus far, rates from data on the procedure exceed this threshold, according to TEC.
CMS acknowledges that data from various industry-backed registries appear to be trending toward improved outcomes. "As additional studies are conducted and experience is gained with the difficult techniques and importantly with appropriate patient selection, we anticipate that the perioperative morbidity and mortality rates will approach the recommended 3% level," the decision states.
The agency decided not to deny coverage to all patients over age 80 as it had suggested it might do in February. CMS says it will monitor study outcomes for this population to determine if such a restriction is warranted at a later date. According to Cordis, 35% of patients at high risk for carotid endarterectomy are over 80 years old.
CMS will still cover carotid stents for high-risk symptomatic patients with between 50% and 70% stenosis only if they are enrolled in a clinical trial. Abbott/Guidant had requested that CMS extend unrestricted coverage to this patient category.
In support of this restriction, CMS cites two European randomized controlled trials, EVA-3S and SPACE. EVA-3S was terminated because of "safety and futility" and SPACE failed to show stenting is non-inferior to surgery, but industry says the stenting procedure evaluated in these trials is not representative of standard U.S. practice.
CMS also clarifies that the procedure is not covered if an embolic protection device cannot be deployed. Embolic protection, which guards against debris traveling to the brain and causing stroke, is part of all carotid stents' FDA indications.
CMS Acknowledges Physician Specialty "Turf Wars"
As Guidant also requested, the final decision removes the coverage condition that an endarterectomy surgeon determine whether the patient is at high risk for surgery. CMS says that requirement would be "overly restrictive."
The agency references a "serious 'turf' war between various physicians who treat carotid artery disease." Cardiology professional societies generally favored expanded coverage for carotid stenting, while groups representing surgeons and neurologists, who have traditionally treated carotid disease, opposed it.
Based on the available evidence, "CMS did the right thing" by not expanding coverage, John Wilson, M.D., Wake Forest University Baptist Medical Center, Winston-Salem, N.C., told "The Gray Sheet." "Turf wars" are irrelevant to best patient care, he said. Wilson is on the cerebrovascular committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.
Cordis noted that its training programs for Precise involve physicians across all specialties, including surgeons.
Industry Forges Ahead With Clinical Trials
Despite stent-makers' disappointment with the decision, in the near term they will continue to focus on treating patients in Medicare-covered clinical trials. Abbott says it will continue to submit data to CMS from its five carotid stenting trials, which enroll a combined 10,000 patients.
Cordis Endovascular is expanding its SAPPHIRE carotid stenting registry for patients at high risk for surgery from 250 sites to 350 sites, according to Shawn McCarthy, carotid disease team leader at the firm.
While McCarthy said Cordis remains committed to treating this high-risk population, he noted that segment is only 30% of the potential patient pool for the procedure. The patients that are not at high risk for endarterectomy represent a much larger piece of the potential market. FDA has yet to approve a carotid stent to treat this normal-risk population.
Cordis plans to soon begin enrolling the CARES trial of Precise in non-high-risk patients.
Results from the National Institutes of Health-sponsored CREST study randomizing normal-risk patients to surgery or stenting are eagerly anticipated. The 2,500-patient trial, initiated in late 2000, is still recruiting and has four-year follow-up.
Abbott is also studying this population in its 1,900-patient ACT I randomized trial. Results from CREST and ACT I are expected to be available within three years, Abbott says.
- Chloe Taft
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