Medicare won’t cover new Alzheimer’s drug until it gets full FDA approval

Leqembi, made by Eisai and Biogen, won accelerated approval in January, but a wider sign-off is not likely until late this year or early 2024.

Biogen, based in Cambridge, has a lot riding on Leqembi, its new treatment for Alzheimer's disease.Adam Glanzman/Photographer: Adam Glanzman/Bloo

A new drug for Alzheimer’s disease is unlikely to be covered by Medicare until federal regulators conduct a more thorough review of the therapy’s effectiveness and safety later this year, according to a statement from the Centers for Medicare & Medicaid Services released Wednesday.

Medicare covers nearly 63 million Americans who are 65 and older. Without the federal health insurance footing the $26,500 annual bill for the drug — let alone the pricey brain scans and biweekly visits to infusion centers that the treatment requires — the vast majority of potential patients who could benefit from it will be unable to afford it.

The drug, called Leqembi, was developed by Cambridge-based Biogen and Japan-based Eisai. Experts anticipate that it could eventually reap billions in annual sales, but now those potential profits have been punted. Last week during a call with investors, Biogen said it expects to lose money on the drug this year.

Leqembi won accelerated approval from the Food and Drug Administration in January. That regulatory pathway can help companies get drugs to patients faster by focusing on changes in a biomarker — such as the shrinking size of a tumor or lower levels of a toxic protein in the brain. But the pathway has come under fire because drug makers frequently fail to complete the required follow-up studies to show whether the medicine actually helps patients.

Biogen and Eisai received accelerated approval for Leqembi by convincing regulators that the antibody drug effectively removed clumps of sticky proteins called amyloid plaques in the brains of people in the early stages of Alzheimer’s. Some scientists believe that clearing these amyloid proteins is key to treating or even preventing the disease. But the approach has so far yielded mixed results.

Aduhelm, a previous drug developed by Biogen and Eisai, modestly slowed cognitive decline in one study but not another, despite lowering amyloid in both trials. The FDA ultimately gave the drug an accelerated approval in 2021, despite questions about its effectiveness and concerns about brain bleeding and swelling that the drug caused in some patients.

Medicare officials subsequently made the unusual decision to restrict coverage of Aduhelm and any future antibody therapies designed to clear amyloid plaques until their manufacturers earned full FDA approval.

Many neuroscientists and neurologists said that the FDA made a mistake in approving Aduhelm, and they applauded the Medicare decision against paying for it. Others lambasted the agency for unprecedented overreach that they said discriminated against Alzheimer’s patients, since the federal insurance has historically covered drugs for other diseases that were granted accelerated approval. Even some Aduhelm detractors worried about Medicare lumping similar drugs in one bucket, saying that each should be evaluated on its own merits.

Eisai ― which is helming interactions with regulators on Leqembi ― and advocacy groups including the Alzheimer’s Association have been pushing for Medicare to reconsider its decision in light of strong data from an advanced clinical trial of 1,800 patients that showed Leqembi could slow cognitive decline by 27 percent over 18 months.

On Wednesday, Medicare regulators said they are not currently reconsidering their previous decision, although they left the door open to potentially doing so in the future. In a statement, Eisai said it “anticipated” this response from Medicare, even though the firm “has not received any details of deficits in the data” that they submitted to the agency for reconsideration.

If an Alzheimer’s drug gets a full approval, Medicare said it will begin covering the drug “on the same day” as long as patients are enrolled in registries to track their outcomes. Earlier this year, Eisai submitted that data to the FDA for full approval. The agency hasn’t set a deadline for when it will make its decision, but the review could last most of the year and possibly spill over into early 2024.