ARTICLE IN BRIEF
The Centers for Medicare and Medicaid Services draft decision not to cover the florbetapir-f18 PET imaging agent for Alzheimer's disease outside of a clinical trial drew mixed response from Alzheimer's disease experts and advocates.
The US Centers for Medicare and Medicaid Services (CMS) have issued a draft coverage decision for the amyloid-tracking PET tracer Amyvid (florbetapir F-18), allowing Medicare to reimburse for florbetapir F-18-aided PET scans only when conducted as part of specific CMS-approved clinical trials (known as a Coverage with Evidence Decision).
The Food and Drug Administration had approved florbetapir F-18 for assessment of Alzheimer's disease (AD) in April 2012, but a CMS advisory panel in January of this year had concluded that there was, at least for now, insufficient evidence for the test's utility outside of a clinical trial setting. Moreover, it found that there was a dearth of data that it would improve health outcomes in suspected cases of AD. The panel gave florbetapir F-18 an average confidence rating of 2.2 out of 5, a lower rating. They indicated that more studies were needed in patients with mild cognitive impairment, and more evidence that the use of the scans could actually change patient management.
MIXED RESPONSE TO FINDING
The Alzheimer's Association and other advocacy organizations immediately prepared to fight the decision — the draft was open to public comment until early August, and a final decision is expected in the fall.
“The Alzheimer's Association is disappointed by the Centers for Medicare & Medicaid Services (CMS) draft coverage decision on brain amyloid imaging, particularly given the clear, scientific consensus recommendations provided to CMS by the Association and the Society for Nuclear Medicine and Molecular Imaging (SNMMI) regarding appropriate, limited coverage, only in specific populations,” the organization said in a statement.
“The Alzheimer's Association understands that CMS' evaluation of the impact of brain amyloid imaging on health outcomes is ongoing, however the needs of Alzheimer's community are acute…Neither families directly impacted by the disease, nor our federal government, can afford to wait as much as seven years for a final decision about national coverage, as was the case with the National Oncology Patient Registry and the evaluation by CMS of FDG PET coverage.”
But David Gill, MD, clinical assistant professor of neurology at the University of Rochester Medical Center, said he agrees with the decision, and has spoken with a number of colleagues who share that opinion.
“At this time, we should be using diagnostic tests that have been shown to make a difference either in diagnostic accuracy or health outcomes, neither of which have been shown for florbetapir F-18,” said Dr. Gill, who serves on the Neurology Today editorial advisory board. “That doesn't mean that it may not end up being a great test, but we just don't have the data to show that yet.”
Leading Alzheimer's expert Oscar Lopez, MD, professor of neurology at the University of Pittsburgh School of Medicine, said the panel will likely have to revisit its assessment very soon.
“We expect at least two or three additional ligands to come out within the next two to three years, which will create a more competitive environment for costs,” he said. “In addition, there will be more studies published regarding the better use of these technologies, and we will be closer to the availability of true anti-amyloid agents.”
Dr. Lopez said that he is disappointed in the decision, but acknowledges the CMS panel's concerns about the current level of evidence. “At this point, we do need to learn more about the technology,” he said. “There are still things we don't know: what it means when a person is amyloid-negative but has clinical symptoms consistent with Alzheimer's disease, what is the outcome. When we think about families and patients, we would like to have a more flexible approach, but the government was more cautious, which was not unexpected. But we will soon know more about the accuracy of these agents. I don't see this as a big setback; it is my impression that this will be revisited in the near future.”
DOES THE TEST HAVE CLINICAL UTILITY?
Paul Aisen, MD, director of the Alzheimer's Disease Cooperative Study and professor of neuroscience at the University of California, San Diego, argues that even before effective anti-amyloid agents become available, florbetapir still has clinical utility outside a trial setting.
“It moves us from having to rely on probable and possible diagnoses to definite diagnoses,” he said. “While that is not necessarily important for the symptomatic treatments we have now — although it will be essential for anti-amyloid treatment — it is nonetheless most useful for the individual and their family. Knowing whether or not you have a progressive neurodegenerative disease is very important for safety considerations, financial planning, and health care planning. A negative scan can eliminate Alzheimer's disease as a possibility.”
But Dr. Gill countered that the florbetapir PET agent is a test for amyloid deposition in the brain, not a test for Alzheimer's disease. “It's then up to the physician to decide what the amyloid means,” he said. “It usually means Alzheimer's, but not always. For example, dementia with Lewy Bodies also involves amyloid, so if you don't ask the right clinical questions, this test may lead you to the wrong conclusion.”
Dr. Aisen said that his center will continue to offer florbetapir PET scans outside the clinical trial setting. “We've found it's very helpful for many families, especially at an early stage when families are concerned, but individuals are not convinced there's anything wrong.” These families will have to shoulder the cost of the scan themselves — about $1500 for the scan, and around $1200 for the tracer.
The Alzheimer's Association and SNMMI in January issued appropriate-use guidelines for amyloid PET imaging, which limits appropriate candidates to:
- Those who complain of persistent or progressive unexplained memory problems or confusion and who demonstrate impairments using standard tests of cognition and memory, whose care would benefit from greater certainty of the underlying pathology.
- Individuals meeting tests for possible Alzheimer's, but who are unusual in their clinical presentation.
- Individuals with progressive dementia and atypically early age of onset (before age 65).
“I'm generally optimistic that we're going to have anti-amyloid treatments, and at that point there's no question that these scans will have to be covered,” Dr. Aisen said. “But whether we'll get coverage prior to that is uncertain.”
Dr. Lopez predicts that CMS may need to take a more flexible approach to the field going forward. “This field is moving so fast in terms of new technologies and diagnostic methodologies that the government may have to be more open at some point.”
•. CMS Transcript — Proposed decision memo for beta amyloid Positron Emission Tomography in dementia and neurodegenerative disease (CAG-00431N): http://go.cms.gov/14S0xIS
•. Johnson KA, Minoshima S, Bohnen NI, et al. Update on appropriate use criteria for amyloid PET imaging: Dementia experts, mild cognitive impairment, and education. Alzheimers Dement. 2013; 9:(4):e 106–109.
•. Johnson KA, Minoshima S, Bohnen NI, et al. Appropriate use criteria for amyloid PET: A report of the Amyloid Imaging Task Force, the Society of Nuclear Medicine, and the Alzheimer's Association. Alzheimers Dement. 2013; 1–15.
•. Neurology Todayvideo with David Gill on amyloid beta, brain volume, and dementia: http://bit.ly/11jOVae