Lecanemab FAQ

At Northwestern Medicine, our patients are our top concern. Know that we closely study each medication before we recommend it for you. We look at its benefits and risks. A new medicine called lecanemab (Leqembi) received accelerated approval by the FDA in January of 2023 after a phase III clinical trial reached completion and showed some potential for benefit.

This is an ongoing process, and we will update this page as we get more information about when this medication may be available to our patients.

What is lecanemab?

Amyloid is a substance that accumulates in the form of plaques in the brain of persons with Alzheimer’s disease. Lecanemab is a medication designed to remove amyloid plaques from the brain. It is in the same class of medications as the previously approved aducanumab (Aduhelm).

It is marketed by Eisai and Biogen as Leqembi. It aims to delay cognitive decline due to Alzheimer’s disease. The results of an 18-month study suggest that this treatment may slow the rate of cognitive decline, though it does not improve cognition or memory. The amount of slowing over an 18-month period is quite small and may not be noticeable by patient, family or physicians. Lecanemab does not reverse existing disease or stop the progression.

What do I need to know about the FDA’s approval of lecanemab?

Lecanemab was approved using the FDA’s accelerated approval pathway. With this faster approval comes a post-approval trial to confirm that the medication provides the expected benefit.

An 18-month clinical trial demonstrated an estimated treatment difference between lecanemab and placebo of 0.373 points of decline from baseline on the CDR-SB (Clinical Dementia Rating Scale-Sum of Boxes, scores range from 0-18). This result means that, although participants declined, they had 27% less decline over an 18-month period.

How is it given?

Patients will receive lecanemab via an infusion into the vein every 2 weeks at an infusion center. The infusion lasts about 1 hour, the entire visit to the infusion center will last about 2 hours.

What is the cost?

Currently, this medication is not covered by insurance or Medicare. We are awaiting CMS (Centers for Medicare & Medicaid Services) determination as to whether this medication will be covered by Medicare. Typically, other private insurance companies follow the lead of CMS when it comes to covering recently approved medications. The price for Leqembi set by Eisai/Biogen is about $26,000 per year. It is important to note that this amount is only for the medication and does not include costs associated with the infusion visits themselves or the MRIs of the brain which will be needed for monitoring of potential side-effects.

View the CMS Statement on FDA Accelerated Approval of Lecanemab.

What are the side effects?

Side effects can include brain swelling and brain bleeds that are usually small. Some patients have also reported headaches, falls, dizziness, vision changes, nausea, diarrhea, seizures, and confusion. Other side effects may include: fever, flu-like symptoms, changes to your heart rate or palpitations, difficulty breathing. There seems to be a higher risk of these side effects in those who have two copies of the E4 variant of the  ApoE gene (a risk gene for Alzheimer’s disease), and we will not be recommending this medication to these patients. The risk of a symptomatic brain bleed also is higher in those on blood thinners, and we will not be recommending this medication for any patient who is on such medications.

Can I receive lecanemab?

Lecanemab is indicated for patients with mild and early stage of cognitive impairment due to Alzheimer’s disease who have evidence of brain plaques by lumbar puncture or amyloid PET scan. Clinicians will prescribe the medication in alignment with strict guidelines. Only specialized clinics will carry this medication.

Are There other FDA-Approved Medications?

There are very safe FDA-approved medications that have been in use for several decades and have been shown to offer symptomatic improvement and may also slow the disease. But these effects, while statistically significant, are very small. Nonetheless, at the Neurobehavior Clinic we routinely use these medications, known as cholinesterase inhibitors. They are donepezil, rivastigmine, and galantamine. These medications can be given in addition to lecanemab.

To learn more, visit the Northwestern Medicine Neurobehavior and Memory Clinic’s website. Talk with your physicians about lecanemab. They will let you know if you are eligible for the medication. They can also explore other treatment options with you.

Last updated: February 2, 2023