Drug reference

lecanemab

Anti-amyloid-β monoclonal antibody (Alzheimer's disease) · Anti-dementia

START

10 mg/kg IV every 2 weeks; MRI before dose 5, 7, 14

TYPICAL MAX

10 mg/kg every 2 weeks

STOP IF

Symptomatic ARIA-E/H, severe infusion reaction, or major haemorrhage

WATCH

Serial MRI surveillance for ARIA; APOE4 genotype (homozygotes have higher ARIA risk); anticoagulation status

CDSCO approvedATC N06DX

Renal dose adjustmenteGFR mL/min/1.73m²

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours

ONSET: 6min · infusion start
PEAK: 1h · end infusion
t½: 6d · t½ ~6 d
DURATION: 2w · q2w

EXCRETION

Proteolytic catabolism; not excreted intact

route + CYP

INTERACTIONS

2 major

SEVERE in our sources

PREGNANCY

Not applicable (typically used in older population).

FDA category + note

Top interactionssee all 5 →

AnticoagulantsSevereDatabaseKimi deep-research + Cla
TpaSevereDatabaseKimi deep-research + Cla

Mechanism

Humanised IgG1 monoclonal antibody selectively targeting soluble amyloid-β protofibrils, the most neurotoxic Aβ species; reduces brain amyloid plaque burden and modestly slows clinical decline in early Alzheimer disease.

Indications

Early Alzheimer disease (mild cognitive impairment / mild dementia stage) with confirmed amyloid pathology

Dosing

Adult: 10 mg/kg IV over ~1 h every 2 weeks; can transition to 10 mg/kg every 4 weeks maintenance after 18 months.
Pediatric: Not applicable.
Renal adjustment: No adjustment.
Hepatic adjustment: No adjustment.
Geriatric: Standard adult dose; primary population.
Max dose: 10 mg/kg every 2 weeks

Pharmacokinetics

Onset

Amyloid reduction over months; clinical effect ~18 months

Peak effect

End of infusion (serum)

Duration

~2-week dosing interval

Half-life

~5–7 days

Bioavailability

IV 100%

Protein binding

Not applicable

Metabolism

Proteolytic catabolism

Excretion

Catabolised; not excreted intact

Contraindications

History of severe hypersensitivity (anaphylaxis, angioedema) to lecanemab
Caution: anticoagulation, cerebral microhaemorrhages on MRI

Side effects

Common

Infusion-related reactionsHeadacheFallAtrial fibrillationARIA (asymptomatic, often)

Serious

Amyloid-related imaging abnormalities (ARIA-E oedema / ARIA-H haemorrhage; boxed)
Severe infusion / hypersensitivity reactions
Intracerebral haemorrhage (esp. with anticoagulation; reported fatal cases)
Severe seizures