Medicare’s Proposed Coverage for Alzheimer’s Scan Could Be Boon for Eisai/Biogen

Pictured: Entrance to the U.S. Department of Health and Human Services Headquarters/iStock, hapabapa

Pictured: Entrance to the U.S. Department of Health and Human Services Headquarters/iStock, hapabapa

Monday, the Centers for Medicare & Medicaid Services (CMS) is prepared to ease the limits on its coverage of PET scans for detecting amyloid plaques in the brains of patients with Alzheimer’s disease. If the proposed change goes into effect, it could mean better business for Eisai, Biogen and other drugmakers whose new Alzheimer’s treatments require such scans.

Previously, the CMS only covered a single round of PET imaging for patients enrolled in clinical studies. Monday’s proposal seeks to remove this cap and leave it up to CMS contractors to determine which patients should be covered by the health insurance program.

“PET scans are an important part of diagnosis and treatment of Alzheimer's disease, and this decision is an important part of CMS’ mission to help improve the lives of Americans we serve," CMS Administrator Chiquita Brooks-LaSure said in a statement, multiple outlets reported.

However, giving contractors the final say on coverage could lead to confusion among beneficiaries and might force the CMS to reconsider its decision, Cowen analyst Eric Assaraf said, according to Reuters.

The proposal for expanded coverage follows the FDA’s full approval of Eisai and Biogen’s Leqembi (lecanemab) earlier this month. Leqembi is the first ever anti-amyloid antibody and disease-altering treatment to be granted traditional approval.

The therapeutic antibody had previously won the regulator’s accelerated approval in January 2023, though access to it remained limited because the CMS only provided coverage to patients enrolled in clinical trials. With its full approval, CMS has stated that it will cover the new treatment for patients with mild cognitive impairment or mild Alzheimer’s disease dementia with evidence of beta-amyloid deposits in the brain. PET scans are used to determine the presence of these amyloid plaques.

Monday’s proposal for coverage expansion could improve the uptake of this diagnostic imaging test and identify a larger population of patients eligible for Leqembi treatment.

The business benefits of expanded PET coverage could also extend to other players in the Alzheimer’s space. Lilly, for instance, is ushering its donanemab through late-stage studies. Most recently, the investigational anti-amyloid antibody aced the Phase III TRAILBLAZER-ALZ 2 trial, leading to a significant reduction in cognitive and functional decline.

Donanemab failed to secure the FDA’s accelerated approval in January 2023 but Lilly said in May that it expected to re-submit to the agency in the second quarter. Participants in donanemab trials have been identified by PET scan as having amyloid plaques in their brains.

Tristan Manalac is an independent science writer based in metro Manila, Philippines. He can be reached at or

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