Medicare will pay for one amyloid PET imaging brain scan per patient, but only if the patient is participating in a federally approved clinical study with an objective of developing better treatments or prevention strategies for Alzheimer’s disease, identifying subpopulations at risk for developing the condition, or ruling out Alzheimer’s disease in difficult differential diagnoses when the use of PET amyloid imaging appears to improve health outcomes.

The announcement Sept. 27 of the agency's final rule on payment for the procedure is in line with a proposal drafted last summer by the Centers for Medicare and Medicaid Services. The recommendation was based on the CMS’s findings of "insufficient evidence" that PET scanning with an amyloid ligand is necessary for diagnosing Alzheimer’s, or that it could be helpful in preventing or treating the disease.

The agency did, however, determine that amyloid imaging could be useful in excluding Alzheimer’s in "narrowly defined and clinically difficult differential diagnoses," such as Alzheimer’s versus frontotemporal dementia. The agents would also be useful in selecting populations enrolled in clinical trials, the CMS said.

Because of these limited applications, the agency will cover the procedure under its Coverage With Evidence Development (CED) program, which provides coverage while collecting additional outcomes data. Coverage under CED contributes to a new technology’s developmental pathway by encouraging more studies that employ it, according to the CMS.

For now, PET amyloid imaging will be covered only in CMS-approved, prospective randomized trials that include subjects from appropriate populations, and, when appropriate, employ the gold standard of postmortem Alzheimer’s diagnosis.

This decision on public coverage will almost certainly affect patients with private insurance as well, according to Dr. Richard J. Caselli, professor of neurology at the Mayo Clinic in Scottsdale, Ariz. and clinical core director of Mayo’s Alzheimer’s disease center.

"Their decision may be reasonable in older patients, which of course is their target patient population, but if other payers follow the CMS model, we will have overlooked the potential utility of this test in young patients, forcing such individuals to either go without or pay out of pocket," he said in an interview. "That is a clinically important issue that does not seem to have been aired in this deliberation."

The decision comes as a blow to Eli Lilly, the company developing florbetapir (Amyvid), one of the amyloid imaging agents. "Coverage With Evidence Development as proposed by CMS does not provide patients appropriate access to these amyloid imaging brain scans," Eric Dozier, the company’s senior director of business, said in a press statement. "Instead, it creates additional complexity for the broader community in determining the best path forward for patients. As we continue to review the final decision memo, we will be evaluating all available options to ensure patients and physicians can gain access to this innovative diagnostic tool as soon as possible."

Lilly said the decision contradicts the CMS’s own support of the National Alzheimer's Project Act, in whose creation it participated. "Yet the same agency is challenging the value of the only technology approved by the Food and Drug Administration for estimating beta-amyloid neuritic plaque density in the living brain, which can aid in helping doctors make a more informed diagnosis."

The decision also goes against the clinical recommendations of several groups, Lilly maintained – including the Alzheimer’s Association, which issued a statement citing its own concern.

"The Alzheimer’s Association is disappointed by the ... decision to only allow Coverage With Evidence Development (CED) for an Alzheimer’s imaging test that would improve diagnostic accuracy and certainty in challenging cases," the statement said. "When used in specific populations ... this tool has the potential to ... resolve distressing medical uncertainty."

Early this year, a task force convened by the Alzheimer’s Association and the Society of Nuclear Medicine and Molecular Imaging developed a set of criteria that would guide the appropriate clinical use of amyloid imaging agents (Alzheimers Dement. 2013;9:E1-16).

The document advised limiting scans to patients with persistent or progressive unexplained memory loss along with cognitive impairments, and those who test as possibly having Alzheimer’s but have an unusual clinical presentation. Imaging would also be appropriate in patients younger than 65 years who present with unexplained memory deficits.

"The Alzheimer’s Association appreciates that the evaluation of the impact of brain amyloid imaging on health outcomes can be complex in the absence of a treatment to stop or even slow the progression of the disease," the association noted. "However, as the scientific community races toward the National Alzheimer's Plan goal of prevention and effective treatment by 2025, many people facing confusion and frustration would benefit from the accurate and accelerated diagnosis this tool could offer."

Dr. Caselli said he had no relevant financial disclosures.

msullivan@frontlinemedcom.com

On Twitter @Alz_Gal

Amyloid imaging scans limited to specific patients in clinical trials