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lecanemab

Leqembi · ATC code N06DX04

Key facts
Active substance
lecanemab
Drug class
Antidementia agent
ATC code
N06DX04
Authorisation
centrally authorised across the EU (EMA)
Dosage forms
LEQEMBI 100 mg/mL concentrate for solution for infusion
Marketing authorisation holder
Eisai GmbH
Information as of
2026-10-27

Key facts

Lecanemab is a monoclonal antibody directed against amyloid beta. It is used in adults with early Alzheimer's disease (mild cognitive impairment or mild dementia) who are ApoE ε4 non-carriers or heterozygotes.

What it is used for

  • Adults with a clinical diagnosis of mild cognitive impairment or mild dementia due to Alzheimer's disease
  • Only in ApoE ε4 non-carriers or heterozygotes with confirmed amyloid pathology; not in homozygotes

Dosing

  • 10 mg/kg body weight as an intravenous infusion once every 2 weeks
  • Before starting: test ApoE ε4 status and confirm amyloid pathology; initiation through a central registration system (controlled access programme)
  • Brain MRI at baseline (within 6 months) and before the 3rd, 5th, 7th and 14th infusions
  • With ARIA, suspend or discontinue dosing depending on symptoms and radiographic severity as set out in the full text
  • Discontinue once the patient progresses to moderate Alzheimer's disease; cognitive assessment approximately every 6 months

Contraindications

  • Hypersensitivity to the active substance or any of the excipients
  • Bleeding disorders not under adequate control
  • Pre-treatment MRI findings of prior intracerebral haemorrhage, more than 4 microhaemorrhages, superficial siderosis, vasogenic oedema or other findings suggestive of cerebral amyloid angiopathy
  • Treatment should not be started in patients on ongoing anticoagulant therapy

Important warnings

  • Amyloid related imaging abnormalities (ARIA-E and ARIA-H), usually early and asymptomatic, rarely serious with seizure or status epilepticus; enhanced vigilance during the first 14 weeks
  • Intracerebral haemorrhages greater than 1 cm, including fatal events; caution in patients with increased bleeding risk
  • Higher ARIA risk in ApoE ε4 homozygotes
  • Hypersensitivity reactions including angioedema, bronchospasm and anaphylaxis; stop the infusion promptly
  • Infusion-related reactions

Side effects

  • Most common in the indicated population: infusion-related reaction (26%), ARIA-H (13%), headache (11%) and ARIA-E (9%)
  • Intracerebral haemorrhage over 1 cm in 0.5% on lecanemab vs 0.1% on placebo; fatal events have been observed
  • Seizures including status epilepticus

Interactions

  • No interaction studies; pharmacokinetic interactions are not expected
  • Anticoagulants or thrombolytic agents may increase the risk of intracerebral haemorrhage

Pregnancy and breastfeeding

  • Pregnancy: no data; not recommended; women of childbearing potential should use effective contraception during treatment and for 2 months after the last dose
  • Breast-feeding: no data; decide between stopping breast-feeding or lecanemab based on benefit and risk

Summary of the official product information, written with AI (Claude, Anthropic) on 2026-10-28. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

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For patients

Package leaflet, verbatim

Package leaflet for patients →

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

EU – centrally authorised (all member states)

  • LeqembiEisai GmbH · EMEA/H/C/005966

Source: European Medicines Agency (EMA), product information

Brand names in 3 more European countries
Iceland
Leqembi
Liechtenstein
Leqembi
Norway
Leqembi

EMA – Article 57 product data (EU/EEA), 2026-10-28

Medelix receives no money from pharmaceutical companies. Brand names are listed alphabetically and without ranking.

Other substances in the same group

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Sources

  1. European Medicines Agency. Leqembi – EPAR, Product Information (OF THE TEXT MM/YYYY Detailed information on this medicinal p). 2026-10-27. https://www.ema.europa.eu/en/documents/product-information/leqembi-epar-product-information_en.pdf
  2. Wikidata (CC0): ATC N06DX.

Editorial: Medelix editorial team · last updated 2026-10-27 · How these pages are made · Report an error

Source: European Medicines Agency (EMA), product information. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.