Lecanemab

Lecanemab
Monoclonal antibody
TypeWhole antibody
SourceHumanized
TargetAmyloid beta
Clinical data
Trade namesLeqembi
Other namesBAN2401, lecanemab-irmb
AHFS/Drugs.comMonograph
License data
Routes of
administration
Intravenous
ATC code
Legal status
Legal status
Identifiers
CAS Number
DrugBank
ChemSpider
  • none
UNII
KEGG
Chemical and physical data
FormulaC6544H10088N1744O2032S46
Molar mass147181.62 g·mol−1

Lecanemab, sold under the brand name Leqembi, is a monoclonal antibody medication used for the treatment of Alzheimer's disease. Lecanemab is an amyloid beta-directed antibody. It is given via intravenous infusion to patients with mild cognitive impairment or mild dementia. In clinical trials, it demonstrated modest efficacy in reducing relative cognitive decline compared to placebo. The most common side effects of lecanemab include headache, infusion-related reactions, and amyloid-related imaging abnormalities, a side effect known to occur with the class of antibodies targeting amyloid.

Lecanemab was jointly developed by Eisai, Biogen and BioArctic. It was granted accelerated approval for medical use in the United States in January 2023, and fully approved by the FDA in July 2023. Lecanemab was approved for medical use in South Korea in May 2024, and in Mexico in December 2024.