A Postmarketing Study of LEQEMBI in South Korean Participants With Alzheimer's Disease

A 6-Year Postmarketing Safety and Clinical Outcome Study of LEQEMBI® in the Treatment of Alzheimer's Disease Using Real-World Data From South Korean Patients Enrolled Into the South Korean JOint RegistrY for ALZheimer's Treatment and Diagnostics (JOY-ALZ) Registry

The primary purpose of this study is to evaluate safety of LEQEMBI in the real-world clinical setting as reported by events of amyloid-related imaging abnormalities (ARIA)-edema (ARIA-E), ARIA-hemosiderin deposition (ARIA-H), symptomatic ARIA-E, symptomatic ARIA-H, and intracerebral hemorrhage (ICH) greater-than 1 centimeter (cm) in patients treated with LEQEMBI.

Study Overview

• Status: Recruiting
• Conditions: Alzheimer's Disease
• Intervention / Treatment: Other: No Intervention

• Study Type: Observational
• Enrollment (Estimated): 3000

Contacts and Locations

• Study Contact: Name: Eisai Korea Inc. Medical department Serena SoYoun Kwon; Phone Number: +82-2-3451-5533; Email: s-kwon@eisaikorea.com

Study Locations

• United States
  • New Jersey
    • Nutley, New Jersey, United States, 07110
      • Recruiting
      • Eisai Trial Site #1

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients with alzheimer's disease prescribed LEQEMBI based on the approved prescribing information in South Korea and clinical judgement.

Description

Inclusion Criteria:

• Enrolled in JOY-ALZ before the decision to treat with LEQEMBI
• The clinical decision to treat with LEQEMBI has already been made
• Provides written informed consent for the use of medical information to be shared with Eisai Korea Inc.

Exclusion Criteria:

• Currently participating in an interventional clinical study

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
LEQEMBI; Patients with alzheimer's disease treated with LEQEMBI in accordance with the approved prescribing information by a physician in routine clinical practice (postmarketing). Data will be collected from the JOY-ALZ registry.	Other: No Intervention; This is a non-interventional study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Adverse Events of Special Interest (AESIs)	AESI will include ARIA-E, ARIA-H, symptomatic ARIA-E, symptomatic ARIA-H, and ICH greater-than 1 cm.	Up to 6 years
Exposure-adjusted Incidence Rate of AESIs	AESI will include ARIA-E, ARIA-H, symptomatic ARIA-E, symptomatic ARIA-H, and ICH greater-than 1 cm.	Up to 6 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Adverse Events (AEs), Adverse drug reactions (ADRs), Serious Adverse Events (SAEs), Serious Adverse Drug Reactions (SADRs)		Up to 6 years
Exposure-Adjusted Incidence Rate of AEs, ADRs, SAEs, SADRs		Up to 6 years
Incidence of AEs and ADRs That are not Reflected in the Approved Prescribing Information		Up to 6 years
Exposure-Adjusted Incidence Rate of AEs and ADRs That are not Reflected in the Approved Prescribing Information		Up to 6 years
Incidence of ARIA-Related Events by Baseline Characteristics	Baseline characteristics include APOE4 genotype status, baseline magnetic resonance imaging (MRI) findings, prior Alzheimer's disease treatments, and antithrombotic therapy.	Up to 6 years
Exposure-Adjusted Incidence Rate of ARIA-Related Events by Baseline Characteristics	Baseline characteristics include APOE4 genotype status, baseline MRI findings, prior Alzheimer's disease treatments, and antithrombotic therapy.	Up to 6 years
Incidence of AEs by Baseline Characteristics	Baseline characteristics will include age, medical history, comorbidities, and concomitant medications.	Up to 6 years
Exposure-Adjusted Incidence Rate of AEs by Baseline Characteristics	Baseline characteristics will include age, medical history, comorbidities, and concomitant medications.	Up to 6 years

Collaborators and Investigators

• Sponsor: Eisai Korea Inc.

Study record dates

Study Major Dates

• Study Start (Actual): February 24, 2025
• Primary Completion (Estimated): September 30, 2029
• Study Completion (Estimated): September 30, 2029

Study Registration Dates

• First Submitted: January 31, 2025
• First Submitted That Met QC Criteria: January 31, 2025
• First Posted (Actual): February 6, 2025

Study Record Updates

• Last Update Posted (Actual): April 21, 2026
• Last Update Submitted That Met QC Criteria: April 16, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Alzheimer's Disease; ARIA; LEQEMBI
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Mental Disorders; Neurocognitive Disorders; Dementia; Tauopathies; Neurodegenerative Diseases; Alzheimer Disease
• Other Study ID Numbers: BAN2401-M082-503

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Eisai's data sharing commitment and further information on how to request data can be found on our website http://eisaiclinicaltrials.com/.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No