A Postmarketing Study of LEQEMBI in United Kingdom (UK) Participants With Alzheimer's Disease (AD)

A Prospective Observational Registry Study to Evaluate the Use and Safety of LEQEMBI in Routine Clinical Practice

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.

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.

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.