HAI Book 2025 - Flipbook - Page 503
Molina-Henry, Doris
Racial and ethnicity differences in plasma biomarker eligibility prior to
amyloid PET imaging in the AHEAD 3-45 Study
Doris Molina-Henry1,8, Rema Raman1,8, Andy Liu1,8, Oliver Langford1,8, Joel Braunstein2, Shobha
Dhadda3, Michael Irrizary3, Joshua Grill4,5,8, Keith Johnson6,7,8, Robert Rissman1,8, Paul Aisen1,8,
Reisa A Sperling6,7,8, AHEAD 3-45 Study Team8
Alzheimer’s Therapeutic Research Institute, University of Southern California, San Diego, CA, US
C2N Diagnostics, St. Louis, MO, US
3
Eisai Inc., Nutley, NJ, US
4
Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA, US
5
University of California Irvine, Irvine, CA, US
6
Massachusetts General Hospital, Harvard Medical School, Boston, MA, US
7
Brigham and Women’s Hospital, Boston, MA, US
8
Alzheimer’s Clinical Trials Consortium, https://www.actcinfo.org/, US
1
2
The AHEAD 3-45 Study utilized a shared screening algorithm to enroll cognitively unimpaired individuals into two
sister trials (A3 and A45) testing targeted dosing of lecanemab based on screening amyloid PET. A major goal of
the AHEAD Study recruitment process was to improve the inclusion of racial and ethnic under-represented
groups (RE-URG). A plasma screening algorithm was introduced as the first step to minimize potential bias in
cognitive and clinical eligibility criteria that disproportionately exclude these groups prior to PET.
We assigned participants in North America to mutually exclusive groups based on self-reported race and
ethnicity: Hispanic Black (HB), Hispanic White (HW), Non-Hispanic Asian (NHA), Non-Hispanic Black (NHB) and
Non-Hispanic White (NHW). A plasma algorithm utilized C2N mass spectrometry for Ab 42/40 and
phosphorylated-tau 217 (p-tau217)/non-phosphorylated-tau (np-tau) ratio, and included age and APOE.
Participants who were
20CL) rates were similar (Figure
1C).
RE-URG showed lower rates of plasma biomarker eligibility, with evidence of an age delay in accumulation
compared to NHW, particularly among APOE e4 carriers. Among plasma eligible participants, PET eligibility rates
were similar across groups, suggesting that the same plasma prediction algorithms were appropriately applied
across race and ethnic groups. These findings support prior evidence suggesting that prevalence of amyloid
pathology may be lower in some RE-URG.
HAI2025 - 503
