lecanemab at a glance
Medicine class
Amyloid beta-directed humanised monoclonal antibody
Licensed use
Early Alzheimer’s disease in adults with one or no ApoE4 gene copies, after amyloid pathology is confirmed
Administration
Intravenous infusion under specialist healthcare supervision
Key safety issue
Amyloid-related imaging abnormalities involving brain swelling or bleeding, monitored using MRI
What is lecanemab used for?
The UK licence covers:
Mild cognitive impairment due to Alzheimer’s disease in adults with confirmed amyloid beta pathology who are ApoE4 non-carriers or heterozygotes.
Mild dementia due to Alzheimer’s disease in the same population.
How does lecanemab work?
Lecanemab binds to aggregated amyloid beta, particularly soluble protofibrils, helping clear these abnormal proteins and reduce amyloid plaques. It can slow cognitive and functional decline but does not restore lost function or cure Alzheimer’s disease.
lecanemab preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 100 mg/mL
How to take lecanemab
Healthcare professionals prepare and give lecanemab as a diluted intravenous infusion. It must not be given as an intravenous push or bolus.
Patients are observed for infusion-related or hypersensitivity reactions.
MRI is required before and during treatment to identify amyloid-related imaging abnormalities.
Food does not affect administration because lecanemab is not taken by mouth.
lecanemab side effects
Common or expected effects
- Infusion-related reactions, including fever, chills, body aches, nausea, vomiting, dizziness or breathing symptoms
- Small areas of bleeding or iron deposition in or around the brain on MRI (ARIA-H)
- Headache
- Falls
- Brain swelling or fluid changes on MRI (ARIA-E)
- Rash
- Atrial fibrillation
Get urgent medical advice
- Symptomatic or severe ARIA, which may cause headache, confusion, visual changes, dizziness, nausea, walking difficulty, focal neurological symptoms or seizures
- Larger bleeding within the brain
- Anaphylaxis or other severe hypersensitivity reactions
lecanemab in pregnancy
There are no adequate pregnancy data. Use requires specialist assessment of potential benefit and fetal risk. Effective contraception is advised during treatment and for three months afterwards; anyone who becomes pregnant should contact their prescriber.
lecanemab while breastfeeding
It is not known whether lecanemab enters human milk or affects a breastfed child. The patient and prescriber should decide whether to stop breastfeeding or lecanemab after considering the benefits of each.
lecanemab interactions
Pharmacokinetic interactions are not generally expected, but medicines affecting blood clotting need particular attention.
Anticoagulants, including warfarin and direct oral anticoagulants
Lecanemab should not be started during ongoing anticoagulant treatment because intracerebral bleeding risk may be increased.
Thrombolytic medicines
These may increase severe intracranial bleeding risk. ARIA can mimic an ischaemic stroke, so emergency clinicians must know about lecanemab treatment.
Aspirin and other antiplatelet medicines
Clinical trials found no increase in ARIA or intracerebral haemorrhage, but individual bleeding risk still requires review.
Common questions about lecanemab
Answers are fully visible for fast scanning and source review.
Is lecanemab a cure for Alzheimer’s disease?
No. It can slow decline in selected people with early Alzheimer’s disease but does not reverse established impairment or cure the disease.
Who can receive lecanemab under its UK licence?
Selected adults with confirmed amyloid pathology and mild cognitive impairment or mild dementia due to Alzheimer’s disease who have one or no ApoE4 gene copies.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.