An experimental drug appears to slow cognitive decline in people with early onset Alzheimer’s.

New data on lecanemab, which is manufactured by Biogen and Esai, was published last week in the New England Journal of Medicine that showed people who took the drug experienced “moderately less decline on measures of cognition and function.”

However, some patients also experienced negative side effects like brain swelling and bleeding — meaning people with early Alzheimer’s disease should be aware of the risks before seeking treatment.

How does it work?

Lecanemab decreases the amount of amyloid plaque in the brain. The protein deposits have long been hypothesized to be linked to the progression of Alzheimer’s.

The theory goes like this: Decrease the plaque and you’ll slow the effects of the memory disease.

The new data on lecanemab provides the strongest support for that theory to date.

“That is huge because it gives the person living with the disease an opportunity to be able to live at a higher level of functioning in their life,” said Keith Gibson, director of diversity, equity and inclusion at the Florida Alzheimer’s Association. “It gives them a greater chance to be as normal as possible before the disease really runs its full course. We’re very, very excited about that.”

The 18-month study, which was funded by its manufacturers and involved people aged 50 to 90 with early Alzheimer’s, nevertheless concluded by noting that “longer trials are warranted to determine the efficacy and safety of lecanemab in early Alzheimer’s disease.”

Who can take it?

The drug is intended for people with early onset Alzheimer’s or mild cognitive impairment.

People who have more advanced stages of Alzheimer’s will likely not be eligible for the treatment.

Given the negative side effects experienced by some patients involved in the study, patients should speak with their doctors when considering whether to seek out lecanemab.

Can I get it now?

People interested in the drug might not have to wait long.

The Food and Drug Administration is considering lecanemab for accelerated approval, and will make its decision on January 6.

How much will it cost?

Esai has said lecanemab could cost between $9,249 and $35,605 a year, a broad estimate that has yet to be narrowed down.

It’s unclear if the drug will be covered by the Centers for Medicare & Medicaid Services should it receive accelerated approval.

Currently, based on an agency decision made in April, Medicare and Medicaid has said it generally will not pay for Alzheimer’s treatments aimed at attacking amyloid plaque until they receive full approval by the Food and Drug Administration, except in clinical trial settings.

A spokesperson for Medicare and Medicaid said it is reviewing the publication in the New England Journal of Medicine and “has met with manufacturers to learn about their efforts” since the April criteria decision.

What if I’m already on another drug that attempts to slow Alzheimer’s?

There’s currently only one drug on the market that attempts to slow progression of Alzheimer’s by reducing the level of plaque in the brain.

Known as Aduhelm or aducanamab, the controversial treatment received federal approval last year, despite limited results that the drug helped patients.

It’s currently unclear how doctors will advise the limited number of patients who are already receiving Aduhelm treatments and want to switch over to lecanemab, which appears to have more conclusive data about its efficacy.

People who are currently taking Aduhelm and are interested in lecanemab should speak to their physicians about next steps.

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