FDA approves new Alzheimer’s medication

Lecanemab slowed patients’ rate of cognitive decline by 27% in a phase 3 trial.

The FDA has approved a new Alzheimer’s medication shown to moderately slow cognitive decline in patients in the early stages of the devastating disease — but it faces hurdles on the way to making a major real-world impact.

The challenge: Alzheimer’s is an incurable brain disorder characterized by problems with memory and cognition. It affects an estimated 6.2 million people in the US, and that number is expected to double by 2050 as the number of seniors grows.

We desperately need new treatment options — to date, the FDA has approved just four Alzheimer’s medications, and three of them only treat symptoms.

The fourth drug — aducanumab — reduces the buildup of amyloid plaques found in the brains of Alzheimer’s patients. This did not lead to any improvement in the cognition of trial participants, though, and many experts have argued that the drug shouldn’t have been approved.

Lecanemab significantly reduced amyloid plaques in the brains of trial participants.

What’s new? The newly approved Alzheimer’s medication, lecanemab, was developed by Japanese pharmaceutical firm Eisai and Biogen, the same Cambridge-based biotech company that developed aducanumab.

In a phase 2 trial involving participants with mild cognitive impairment or early-stage Alzheimer’s, an infusion of lecanemab every two weeks for 18 months significantly reduced amyloid plaques in the brain.

Based on that data, included in an application it received in July 2022, the FDA has decided to grant the new Alzheimer’s medication “accelerated approval,” meaning it expects the drug to provide a clinical benefit to patients — even if it hasn’t seen evidence of that benefit yet.

Lecanemab’s makers will now need to demonstrate that benefit through additional studies or risk having the drug pulled from the market.

“It’s not a cure … But it does slow down progression in very mild disease.”

Joy Snider

Meeting expectations: The same day the FDA granted lecanemab accelerated approval, the drug’s makers submitted an application for full approval.

That application included data from a phase 3 trial involving nearly 1,800 people with early-stage Alzheimer’s. It found that, compared to a placebo, the new Alzheimer’s medication slowed the rate of cognitive decline in patients by 27% after 18 months.

“It’s not a cure. It doesn’t stop the disease completely. It doesn’t make people get better,” Joy Snider, a neurology professor at Washington University School of Medicine in St. Louis, who wasn’t involved in the trial, told NPR. “But it does slow down progression in very mild disease.”

The cold water: A year’s worth of lecanemad will cost $26,500, and Eisai’s CEO Ivan Cheung has estimated that most people might need to be on the med for at least three years.

Because Medicare doesn’t cover amyloid-targeting Alzheimer’s medications granted accelerated approval, seniors relying on that program for their health insurance will need to pay for the drug out of pocket, unless and until it receives full approval.

Lecanemab also carries a risk of serious side effects, such as brain swelling or bleeding, so people on the new Alzheimer’s medication will need to get regular brain scans to catch any such problems early — and the cost of those procedures would be on top of the medication price.

The big picture: It’s likely many Alzheimer’s patients will see the high cost of lecanemad as worth paying — slowed disease progression could mean prolonged independence, more quality time with loved ones, and other markers associated with a higher quality of life.

“This treatment can change the course of Alzheimer’s in a meaningful way for people in the early stages of the disease,” said Maria Carrillo, CSO of the Alzheimer’s Association.

We’d love to hear from you! If you have a comment about this article or if you have a tip for a future Freethink story, please email us at [email protected].

Do we finally know what causes Alzheimer’s?
The first treatments proven to slow cognitive decline in Alzheimer’s are helping settle a decades-long debate about how the disease starts.
Paralyzed man walks again using only his thoughts 
A man with paralyzed legs is walking again thanks to a “digital bridge” between his brain and a spinal stimulator.
This “bridge” between chemo and cancer solves a big problem for treatment
To improve leukemia treatment, Australian researchers have created a bispecific antibody that connects chemo drugs to cancer cells.
Cancer treatment is about to get a reboot, thanks to AI
Techniques borrowed from astrophysics are helping to advance personalized cancer treatments beyond what genetics can tell us.
Depression treatment reverses “backwards” brain signals
Transcranial magnetic stimulation (TMS) appears to relieve depression by correcting brain signals that are traveling the wrong direction.
Subscribe to Freethink for more great stories