A Study to Confirm Safety and Efficacy of Lecanemab in Participants With Early Alzheimer's Disease

Brief summary

This study will be conducted to evaluate the efficacy of lecanemab in participants with early Alzheimer's disease (EAD) by determining the superiority of lecanemab compared with placebo on the change from baseline in the Clinical Dementia Rating-Sum of Boxes (CDR-SB) at 18 months of treatment in the Core Study. This study will also evaluate the long-term safety and tolerability of lecanemab in participants with EAD in the Extension Phase and whether the long-term effects of lecanemab as measured by the CDR-SB at the end of the Core Study is maintained over time in the Extension Phase. Extension Phase Part B will continue dosing with lecanemab in countries where lecanemab may not be commercially available.

Source: ClinicalTrials.gov (U.S. National Library of Medicine), data processed 2026-10-29T09:00:05; modifications: selected fields only; whitespace normalized; brief summary truncated to 2,000 characters. Not a U.S. Government endorsement.

Trial details

acronym

Clarity AD

status

ACTIVE_NOT_RECRUITING

phase

PHASE3

study type

INTERVENTIONAL

enrollment

1906

sponsor

Eisai Inc.

conditions

Early Alzheimer's Disease

interventions

DRUG: Lecanemab IV; DRUG: Placebo; DRUG: Lecanemab SC

start date

2019-03-27

start date type

ACTUAL

primary completion date

2026-12-31

has results

false

data source

ClinicalTrials.gov

data processed

2026-10-29T09:00:05

modifications

selected fields only; whitespace normalized; brief summary truncated to 2,000 characters