A Study for Long Term Evaluation of Amyloid Risk and Neurodegeneration


About this study

The purpose of this study is to evaluate the rate of cognitive change in clinically normal older individuals who "screen-failed" for the A4 trial on the basis of their screening PET imaging not demonstrating evidence of elevated amyloid accumulation ( were Aβ negative) but met all other A4 study eligibility criteria. While long term data suggests that older individuals with elevated Aβ burden are at increased risk of cognitive decline, it is important to demonstrate the different rate of clinical decline between Aβe ("Aβ elevated") and Aβne ("Aβ not elevated") individuals.  

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

  • Consented to participate in the A4 study and previously met A4 demographic, cognitive and clinical criteria (e.g., Mini-Mental State Examination (MMSE), Clinical Dementia Ratin (CDR), Logical Memory test, part IIa (LMIIa), medications, medical history)
  • Has a florbetapir PET scan that falls below the Aβ threshold levels required for randomization into the treatment arms of the A4 trial
  • In general, permitted medications should be stable for 8 weeks prior to LEARN visit 1
  • Changes to medications that, in the opinion of the investigator, are not likely to impact LEARN visit 1 assessments are permissible
  • Has a study partner that is willing to participate as a source of information and has at least weekly contact with the subject (contact can be in-person, via telephone or electronic communication)
    • The study partner must have sufficient contact such that the investigator feels the study partner can provide meaningful information about the subject's daily function
  • In the investigator's opinion, is both willing and able to participate in all required procedures for the duration of the study (at least 168 weeks), including adequate literacy in English or Spanish and adequate vision and hearing to complete the required psychometric tests

Exclusion Criteria

  • Is receiving a prescription acetylcholinesterase inhibitor (AChEI) and/or memantine at LEARN visit 1
  • Has current serious or unstable illness including cardiovascular, hepatic, renal, gastroenterologic, respiratory, endocrinologic, neurologic, psychiatric, immunologic, or hematologic disease or other conditions that, in the investigator's opinion, could interfere with the analyses of safety and efficacy in this study
  • Has any contraindications for MRI studies, including claustrophobia, the presence of metal (ferromagnetic) implants, or a cardiac pacemaker that is not compatible with MRI
  • Has a LEARN visit 1 MRI scan with results showing >4 hemosiderin deposits (definite microhemorrhages or areas of superficial siderosis) or any amyloid-related imaging abnormalities - edema/effusions (ARIA-E)
  • Has received any exclusionary medication, including those with significant central nervous system (CNS) anticholinergic effects, within 3 months prior to LEARN visit 1 or initiated at any point after screen
    • A full list of exclusionary medication will be provided in the relevant procedures manual.
  • Is currently enrolled in a clinical trial involving an investigational product or non-approved use of a drug or device, or concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study
    • Participation in observational studies may be permitted upon review of the observational study protocol and approval by the Project Director or one of the ADCS Medical Monitors
  • For subjects participating in the optional Lumbar Puncture,  all of the above plus
    • Current use of anticoagulants, such as warfarin or dabigatran

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Jacksonville, Fla.

Mayo Clinic principal investigator

Neill Graff Radford, M.D.

Closed for enrollment

Contact information:

Memory Disorder Clinic - FL


Rochester, Minn.

Mayo Clinic principal investigator

David Knopman, M.D.

Closed for enrollment

Contact information:

Alzheimer’s Disease Research Center

(507) 284-1324

More information


Publications are currently not available

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