Drug Information

Lecanemab (LeqembiTM) is a monoclonal antibody that binds amyloid-β aggregates in the brain. It is delivered as infusions every two weeks. The FDA has fully approval lecanemab for eligible patients with mild cognitive impairment due to Alzheimer’s disease or mild Alzheimer’s disease.


The drug has been studied in patients with mild cognitive impairment due to Alzheimer’s disease or mild Alzheimer’s disease. Its effects in patients without cognitive impairment or moderate-to-severe Alzheimer’s disease are unknown.


The most common side effects are infusion-related reactions (26% vs. 7% in placebo group), bleeding in the brain or brain lining (17% vs. 9% in placebo group), and brain swelling (13% vs. 2% in placebo group). Adverse effects are more common in Alzheimer’s patients who carry the APOE ε4 (APOE4) gene.


In a phase 3 clinical trial, that was conducted at several sites including UCLA, patients treated with lecanemab for 18 months experienced moderately less decline in measures of memory, judgement, and other abilities compared with patients taking placebo.


Lecanemab is currently marketed at $26,500 a year for a person of average weight. Additional costs associated with use of this drug include amyloid biomarker assessments (e.g., amyloid-PET), genetic testing, and serial brain MRIs to monitor safety.

Medicare Coverage

Medicare coverage is available for lecanemab for patients that are enrolled in a registry that is approved by the Centers for Medicare & Medicaid Services (CMS). More information will be added as it becomes available.

Ongoing Clinical Trials

The Easton Center’s Kagan Clinical Trials Program is participating in the open-label extension of Clarity AD, which is currently a single-arm clinical safety study with a 4-year treatment period. This study includes an option for a weekly injection of this drug under the skin instead of infusions every two weeks.


Clinic: Lecanemab is currently not available on the drug formulary at UCLA Health.

For further reading, see Dr. Vossel’s interview about lecanemab in the Daily Mail.