Medications like lecanemab (Leqembi) and donanemab (Kisunla) target amyloid plaques in the brain that build up due to Alzheimer’s disease. They may help slow disease progression for people in the early stages of Alzheimer’s.

Alzheimer’s is the most common cause of dementia among older adults in the United States. While there’s no cure, treatment aims to manage symptoms and improve quality of life.

An emerging class of treatments may provide a new way of treating Alzheimer’s. Anti-amyloid medications work inside the brain to prevent Alzheimer’s disease from progressing. While this field is still relatively new, the prospects are exciting.

Keep reading to learn about the pros and cons of anti-amyloid therapies in treating Alzheimer’s disease.

Part of the disease process of Alzheimer’s is the buildup of beta-amyloid protein in the brain. This leads to the formation of amyloid plaques that disrupt pathways in the brain and trigger the death of brain cells.

Anti-amyloid treatments target these amyloid plaques. They are monoclonal antibodies (synthesized proteins) that attach themselves to beta-amyloid, marking them for removal by your immune system.

This targeted action can help slow disease progression. It may also slow cognitive decline by 20% to 40%.

Two anti-amyloid medications are currently available in the United States:

The Food and Drug Administration (FDA) approved lecanemab in 2023 and donanemab in 2024.

Both are intravenous infusions that a healthcare professional must administer. The frequency of the infusions differs between the two options. People who take lecanemab receive infusions every 2 weeks, while those who take donanemab receive infusions every 4 weeks.

A previous option, aducanumab (Aduhelm), was discontinued in 2024.

Emerging anti-amyloid therapies

Anti-amyloid therapies are getting a lot of attention in current Alzheimer’s research. Researchers are working on new anti-amyloid treatments that are currently still in the experimental phase.

Two of the most promising options are remternetug, which is an updated version of donanemab, and trontinemab, a modified version of a previously promising drug (gantenerumab).

Traditional Alzheimer’s treatments focus on managing symptoms. Anti-amyloid medications instead aim to target the amyloid plaques that contribute to brain changes in people with Alzheimer’s.

Unlike other Alzheimer’s treatments, amyloid-targeting therapies have the potential to slow disease progression. However, they can’t cure or reverse Alzheimer’s.

Despite this potential, anti-amyloid medications have shown only modest effects. Still, they represent an important pathway to treating Alzheimer’s and the most promising avenue of research.

Pros of anti-amyloid medications for Alzheimer’s

  • target beta-amyloid buildup in the brain
  • may slow disease progression
  • may slow cognitive decline

Cons of anti-amyloid medications for Alzheimer’s

  • effective in the early stages of Alzheimer’s only
  • may have significant side effects
  • much costlier than other Alzheimer’s medications

Anti-amyloid treatments are best suited for people in the early stages of Alzheimer’s disease.

Amyloid plaques begin to form as many as 20 years before the appearance of any Alzheimer’s symptoms. In the later stages, other factors, like tau tangles, contribute to symptoms and disease progression. At these stages, acting on amyloid plaques alone is not enough to treat the disease.

The FDA has approved lecanemab and donanemab for people with mild cognitive impairment or mild dementia due to Alzheimer’s.

To receive these treatments, a doctor must also confirm that you have amyloid plaques in your brain. They can do this using a PET scan or a spinal fluid test.

Mild side effects of anti-amyloid treatments include:

  • headache
  • cough
  • diarrhea
  • nausea and vomiting
  • rash
  • infusion-related reactions

The most serious side effect of anti-amyloid treatments is amyloid-related imaging abnormalities (ARIA). Those are changes in the brain that doctors observe on an MRI. ARIA usually presents as swelling or bleeding in the brain.

ARIA typically doesn’t cause symptoms, but it can lead to headaches, dizziness, or seizures. In rare cases, ARIA can be fatal, so it’s essential for a doctor to monitor anyone taking amyloid-targeting medications.

Anti-amyloid treatments are much more expensive than traditional Alzheimer’s medications. People who take these medications also need to undergo extra procedures, such as PET and MRI scans, which can increase costs.

Leqembi and Kisunla are both biologic drugs, which are expensive to research and produce. People sometimes save money by choosing biosimilars, which are different versions of the original biologic that work in the same way. However, because Leqembi and Kisunla are newer drugs, more affordable biosimilars are not yet available.

How much you pay for these medications will ultimately depend on your insurance coverage.

More about affording anti-amyloid treatments

Visit these Healthline resources to learn more about the cost of available anti-amyloid therapies and what financial support may be available:

Anti-amyloid medications can help treat people in the early stages of Alzheimer’s by removing amyloid plaques from the brain. Although they’re not a cure for Alzheimer’s, they may help slow disease progression and cognitive decline.

But they’re not for everyone. A doctor needs to confirm the presence of amyloid buildup in the brain and that the person with Alzheimer’s hasn’t progressed to more severe dementia. These treatments may also come with some unique side effects and cost more than traditional Alzheimer’s treatments.

Talk with a doctor about whether anti-amyloid treatments — whether those currently available or in clinical trials — may be an appropriate treatment.