An observational study in Alzheimer's Disease, sponsored by Eisai Co., Ltd.. Recruiting at 3 sites in Japan. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-01-23.
Sponsored by Eisai Co., Ltd. · Observational
The primary purpose of this study is to investigate the characteristics of amyloid related imaging abnormalities (ARIA) and investigate the treatment continuation status (e.g., continuation, interruption) after the onset of ARIA in routine clinical practice in participants treated with lecanemab.
3,965 studies on the registry are indexed under Alzheimer Disease; 926 are open to participants now.
This study's planned enrollment of 5,000 is above the median of 200 across 814 observational studies indexed under Alzheimer Disease.
Browse Alzheimer Disease studies →Eisai Co., Ltd. is the lead sponsor of 152 studies on the registry; 5 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Participants prescribed lecanemab by a physician in routine clinical practice.
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Exclusion Criteria:
Participants prescribed lecanemab by a physician in routine clinical practice (post-marketing surveillance) will be observed prospectively for up to a maximum of 156 weeks or to the time of discontinuation, whichever occurs first.
Other: No Intervention
This is a non-interventional study.
Number of Participants With Amyloid Related Imaging Abnormality-Oedema/Effusion (ARIA-E) and Amyloid Related Imaging Abnormality-Microhemorrhage and Hemosiderin Deposit, and Cerebellar Microhaemorrhage (ARIA-H)
Time frame: Up to 156 weeks
Number of Participants With Interruption or Discontinuation of Lecanemab After Onset of ARIA
Time frame: Up to 156 weeks
Number of Participants With Infusion Related Reaction
Time frame: Up to 156 weeks
Plan to share: Yes — Eisai's data sharing commitment and further information on how to request data can be found on our website http://eisaiclinicaltrials.com/.
No publications or documents are linked to this record.
Started Feb 2024 (actual). Primary completion is estimated for Dec 2027, 46 months after the start.
Of 41 industry-sponsored observational studies under Alzheimer Disease, half reached primary completion within 34 months of starting (the median), counting those still running; a quarter within 20 and three quarters within 63. This study's planned 46 months is above that.
Counting every sponsor, half of 405 studies reached it within 67 months; a quarter within 35 and three quarters within 171.
How these figures are worked out, and which studies are left out of them.
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