A Postmarketing Study of LEQEMBI in United Kingdom (UK) Participants With Alzheimer's Disease (AD)
Alzheimers Disease
What this study involves
The registry does not currently label this study as recruiting. Ask about its status before planning a screening visit.
- Study type
- Observational
- Phase
- Not applicable / not listed
- Age range
- Not specified - Not specified
- Sex eligible
- All sexes
- Healthy volunteers
- Not accepted
- Participants
- 400 Estimated
These are starting points, not an eligibility decision. The research team must review the full requirements.
About the research
The primary purpose of the study is to describe the incidence and severity of known adverse events (AEs), including Amyloid-Related Imaging Abnormalities Oedema/Effusion (ARIA-E), Amyloid-Related Imaging Abnormalities-Microhemorrhage and Haemosiderin Deposit (ARIA-H), intracerebral hemorrhage greater than (\>) 1 centimeter (cm) in diameter, and anaphylaxis (stratified by apolipoprotein E4 variant \[APOE4\] genotype, concomitant antithrombotic therapy, and comorbid Cerebral Amyloid Angiopathy \[CAA\]), of LEQEMBI in routine clinical practice.
Read the full description
This is a Post-Authorisation Safety Study registry designed to evaluate the safety, benefit-risk profile, drug utilisation, and effectiveness of risk minimisation measures of LEQEMBI in patients with AD in routine clinical practice
The secondary purposes of the study are:
- To describe the benefit-risk profile of LEQEMBI in routine clinical practice across patient subgroups as determined by progression to the next stage of AD (stratified by APOE4 genotype, concomitant antithrombotic therapy, and comorbid CAA).
- To describe previously unknown AEs related to long-term safety of LEQEMBI in routine clinical practice, which were not identified in clinical development, as assessed by serious suspected adverse reactions and adverse reactions leading to discontinuation of LEQEMBI treatment.
- To describe drug utilisation of LEQEMBI and effectiveness of risk minimisation measures in routine clinical practice.
Who may be able to participate?
The list below is the sponsor’s full registry wording. It can include conditions, prior treatment, test results and other requirements. A match in search does not mean you qualify.
Inclusion Criteria:
- The participant (and/or legally authorised representative) has provided written informed consent to participate in the Post-Authorisation Safety Study (PASS) and for use of their protected health information (PHI).
- The participant is registered in the Controlled Access Programme (CAP) and has been prescribed LEQEMBI.
Exclusion Criteria:
-Participation or planning to participate in randomised controlled trials (RCTs) for mild cognitive impairment (MCI) or AD, and patients who have had prior exposure to anti-amyloid monoclonal antibody (mAb) treatment including prior use of lecanemab.
Study population
Participants with AD who are prescribed LEQEMBI by a physician in routine clinical practice in the UK.
Understand screeningTreatment, groups and participation
The registry may describe treatments and study duration without a complete visit calendar. Ask the study team for the exact schedule, procedures, risks, costs and alternatives. Keep your usual care plan unless your treating clinician tells you otherwise.
- Assignment
- Not reported
- Masking
- Not reported
Participants Treated With LEQEMBI
Not reported in this registry record.
Other: No Intervention
No Intervention OTHER
No intervention.
What researchers are measuring
Outcome measures describe what is being studied. They are not proof that a treatment works.
Primary measures
Incidence and Severity of ARIA-E, ARIA-H, Intracerebral Hemorrhage >1 cm in Diameter and Anaphylaxis
Time frame: Up to 3 years
Not reported in this registry record.
Secondary measures
Time to Progression to the Next Stage of Alzheimer's Disease (AD)
Time frame: Up to 3 years
Not reported in this registry record.
Incidence and Severity of Serious Suspected Adverse Reactions and Adverse Reactions Leading to Discontinuation of LEQEMBI Treatment
Time frame: Up to 3 years
Not reported in this registry record.
Drug Utilisation of LEQEMBI Based on Baseline Characteristics
Time frame: Up to 3 years
Baseline demographics will include age/age group, sex, race, ethnicity, clinical disease stage, APOE4 genotypes, diagnosis of AD, baseline magnetic resonance imaging (MRI) findings consistent with a high risk of cerebral amyloid angiopathy (CAA), use of AD treatment, and use of concomitant antithrombotic medications at baseline.
Duration of Treatment
Time frame: Up to 3 years
Drug Utilization of LEQEMBI will be assessed by Duration of Treatment
Incidence of Serious ARIA and ICH
Time frame: Up to 3 years
Incidence of serious ARIA and ICH \>1 cm in diameter will be assessed
Effectiveness of Risk Minimization Measures
Time frame: Up to 3 years
Percentage of participants with use of antithrombotic medications, demonstrating compliance with magnetic resonance imaging (MRI) monitoring schedule, demonstrating compliance with dose suspension or discontinuation, and, physician compliance with the Summary of Product Characteristics (SmPC) and provision of participant with the Patient Alert Card (PAC) and Patient Information Leaflet (PIL).
Review the complete result tables and limitations in the official record.
Open official results ↗Research locations (3)
The overall study status and a local site’s status can differ. Confirm that location’s availability before traveling.
3 locations
Scottish Brain SciencesEdinburgh, United KingdomStatus unknown
Recognition Health LimitedLondon, United KingdomStatus unknown
NeuroclnxMotherwell, United KingdomStatus unknown
Study team and timeline
- Lead sponsor
- Eisai Limited
- Study start
- Dec 30, 2026 Estimated
- Primary completion
- Dec 31, 2031 Estimated
- Study completion
- Dec 31, 2031 Estimated
- First posted
- Aug 24, 2026 Actual
- Last updated
- Nov 10, 2026 Actual
Official study contacts
Official study title
A Prospective Observational Registry Study to Evaluate the Use and Safety of LEQEMBI in Routine Clinical Practice
Ask Wellness Clinical Research
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Source: ClinicalTrials.gov API v2. Information is submitted by sponsors and investigators. NLM does not approve the safety or science of all listed studies. Registry disclaimer.
Retrieved: Nov 12, 2026 · Last registry update: Nov 10, 2026