Longitudinal Evaluation of Amyloid Risk and Neurodegeneration – the LEARN Study
About the Learn Study
The LEARN study is a multicenter, observational study will that will evaluate the rate of cognitive change in approximately 500 clinically normal older individuals who “screen-fail” for the A4 trial on the basis of their screening PET imaging not demonstrating evidence of elevated amyloid accumulation (Aβ negative) but meet all other A4 study eligibility criteria. This study will leverage the A4 infrastructure and maximize the data acquired in screening a large number of well-characterized older adults for the A4 trial.
The LEARN observational cohort will provide a critical comparison group for the A4 placebo arm, and future trials in preclinical AD. Although accumulating longitudinal data suggest that older individuals with elevated Aβ burden are at increased risk of cognitive decline, it is important to demonstrate a differential rate of clinical decline between Aβe (“Aβ elevated”) and Aβne (“Aβ not elevated”) individuals on a standardized set of clinical outcomes. Over 2000 well-characterized, highly motivated older volunteers will “screen fail” for the A4 trial. The LEARN study will follow 500 of these individuals, matched as closely as possible to the two treatment arms, in this observation cohort. The LEARN study may selectively recruit from a specific range of SUVr that fall below the threshold for “elevated amyloid” in order to support analyses of the relationship of baseline SUVr to subsequent cognitive change and amyloid accumulation. The observational cohort will be followed for 384 weeks with identical clinical/cognitive testing performed every 24 weeks, running parallel to the A4 treatment study and open label extension.
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 240 weeks), including adequate literacy in English or Spanish and adequate vision and hearing to complete the required psychometric tests.