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Find more clinical trials

Lecanemab for People with Early Alzheimer's Disease (Clarity AD)

Start: March 27, 2019
End: September 2027
Enrollment: 1766

What Is This Study About?

This Phase 3 trial will test the effectiveness of the experimental drug Lecanemab as a possible treatment for Alzheimer's disease. Lecanemab is a monoclonal antibody that interferes with the formation of amyloid plaque, a hallmark of Alzheimer's. This 18-month study will test the effectiveness of the study drug in people with MCI or early Alzheimer's disease. Participants will be randomly assigned to an intravenous infusion of either the study drug or a placebo every two weeks for 18 months.

Do I Qualify To Participate in This Study?

Minimum Age: 50 Years

Maximum Age: 90 Years

Must have:

Participants with Mild Cognitive Impairment (MCI) Due to Alzheimer's:

  • Meet the National Institute of Aging-Alzheimer's Association (NIA-AA) core clinical criteria for intermediate likelihood of MCI due to Alzheimer's
  • Have a global Clinical Dementia Rating (CDR) score of 0.5 and CDR Memory Box score of 0.5 or greater
  • Reported history of subjective memory decline with gradual onset and slow progression over the last 1 year 

Participants with Mild Alzheimer's Disease:

  • Meet the NIA-AA core clinical criteria for probable Alzheimer's disease dementia and have a global CDR score of 0.5 to 1 and a CDR Memory Box score of 0.5 or greater

All Participants:

  • Objective impairment in episodic memory as indicated by at least 1 standard deviation below age-adjusted mean in the Wechsler Memory Scale IV-Logical Memory II
  • Positive measure of brain amyloid pathology
  • Mini-Mental State Examination score of 22 to 30
  • Body mass index of 17 to 35
  • If taking Alzheimer's medications, including acetylcholinesterase inhibitors and/or memantine, must be on a stable dose for at least 12 weeks
  • Must have been on stable doses of all other permitted medications for at least 4 weeks
  • Have a study partner who is able to support and spend at least 8 hours each week with the participant
  • Able to provide written informed consent personally or through a legal representative

Must NOT have:

  • Any neurological condition other than Alzheimer's disease that may be contributing to cognitive impairment
  • History of transient ischemic attacks, stroke, or seizures within past year
  • Any psychiatric diagnosis or symptoms, such as hallucinations, major depression, or delusions, that could interfere with study
  • Geriatric Depression Scale score of 8 or greater
  • Inability to undergo magnetic resonance imaging (MRI), including cardiac pacemaker/defibrillator and metal implants
  • Evidence of other significant lesions on brain MRI that could indicate a dementia diagnosis other than Alzheimer's disease
  • Any other unstable or not adequately controlled medical condition, such as a bleeding disorder, cardiac, respiratory, gastrointestinal, or liver disease, or conditions that could affect participant safety or interfere with study assessments
  • Prior exposure to Lecanemab
  • Participation in any clinical studies that included therapeutic monoclonal antibody, protein derived from monoclonal antibody, immunoglobulin therapy, or vaccines in the last 6 months unless documented that the participant was in the placebo group
  • Participation in any clinical studies that included anti-amyloid therapies or chemicals to treat Alzheimer's disease in the last 6 months unless documented that the participant was in the placebo group

If I Qualify, Who Do I Contact?

Contact study personnel listed either under the general study contact or the location nearest you.


Who Is the General Study Contact?

For more information on this trial, contact Eisai Medical Information at 888-274-2378 or

Need Help?

Contact NIA’s Alzheimer’s and related Dementias Education and Referral (ADEAR) Center at 800-438-4380 or email ADEAR.

Where Is This Study Located?

Who Sponsors This Study?

Lead: Eisai Inc.

Collaborator Sponsor

  • Biogen

Source: ID: NCT03887455

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