Anti-amyloid mAbs (lecanemab / donanemab / aducanumab)
Cognitive · Amyloid-beta-targeting monoclonal antibody
Tier D-
Bottom line
Read Off Label grades Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) as D- (2.6/10) based on weak-moderate evidence, low-moderate benefit magnitude, and a high-risk safety profile.
Cochrane 2026 (Nonino et al, n=20342 across 17 RCTs): the entire class produces only trivial cognitive (SMD -0.
Typical use: Lecanemab 10 mg/kg IV q2 weeks; donanemab 700 mg IV q4 weeks for 3 doses then 1400 mg IV q4 weeks — Rx.
What this is
Cochrane 2026 (Nonino et al, n=20342 across 17 RCTs): the entire class produces only trivial cognitive (SMD -0.11) and dementia-severity (SMD -0.12) benefit while consistently increasing ARIA-E. Authors conclude 'successful removal of amyloid does not seem to be associated with clinically meaningful effects' and 'future research should focus on other mechanisms of action.' Costly (~$26K/year for lecanemab); requires APOE genotyping (4/4 homozygotes excluded or carefully monitored due to ARIA risk); MRI surveillance every dose. 2026 regulatory refinements: FDA approved a modified donanemab titration (TRAILBLAZER-ALZ 6) that significantly lowers ARIA-E incidence and severity (most benefit in APOE4 carriers), and accepted a lecanemab subcutaneous maintenance autoinjector (LEQEMBI IQLIK) for weekly home dosing - convenience plus a somewhat improved titration-safety story, though the trivial-clinical-benefit conclusion is unchanged. Indirect comparisons show lecanemab carries lower ARIA risk than donanemab.
Mechanism
Monoclonal antibodies bind aggregated amyloid-beta protein in brain (lecanemab targets soluble protofibrils; donanemab targets pyroglutamate amyloid plaques; aducanumab targets fibrillar Aβ) — drive amyloid clearance via Fc-mediated microglial phagocytosis. First disease-modifying drugs for Alzheimer's based on the amyloid hypothesis
Dose & route
Lecanemab 10 mg/kg IV q2 weeks; donanemab 700 mg IV q4 weeks for 3 doses then 1400 mg IV q4 weeks
Citations
- https://doi.org/10.1002/14651858.CD016297
- https://www.nejm.org/doi/full/10.1056/NEJMoa2212948
- https://jamanetwork.com/journals/jama/fullarticle/2820925
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Common questions
- Does Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) work?
- Read Off Label rates the evidence for Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) as Weak-Moderate and the benefit magnitude as low-moderate, producing an overall grade of D- (2.6/10). Cochrane 2026 (Nonino et al, n=20342 across 17 RCTs): the entire class produces only trivial cognitive (SMD -0.
- Is Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) safe?
- Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) has a high risk profile in published human data. Legal status: Rx (lecanemab/Leqembi FDA-approved Jan 2023; donanemab/Kisunla FDA-approved July 2024; aducanumab/Aduhelm WITHDRAWN by Biogen Jan 2024). This is not medical advice — see the disclaimer.
- What is the typical dose for Anti-amyloid mAbs (lecanemab / donanemab / aducanumab)?
- Lecanemab 10 mg/kg IV q2 weeks; donanemab 700 mg IV q4 weeks for 3 doses then 1400 mg IV q4 weeks
- How does Anti-amyloid mAbs (lecanemab / donanemab / aducanumab) work?
- Monoclonal antibodies bind aggregated amyloid-beta protein in brain (lecanemab targets soluble protofibrils; donanemab targets pyroglutamate amyloid plaques; aducanumab targets fibrillar Aβ) — drive amyloid clearance via Fc-mediated microglial phagocytosis. First disease-modifying drugs for Alzheimer's based on the amyloid hypothesis
This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.