New Blood Biomarkers Reveal Variations in Alzheimer's Disease Trial Eligibility Across Diverse Populations

Recent research utilizing advanced blood biomarkers has shed light on discrepancies in Alzheimer's disease trial eligibility among different racial and ethnic groups. The study, led by scientists from the Keck School of Medicine of USC, focused on the use of the novel blood test p-tau217, which more precisely detects early Alzheimer’s-related changes in the brain. Elevated amyloid levels in the brain, a hallmark of Alzheimer's, are typically necessary for participation in clinical trials targeting the disease.

The findings indicate that individuals from African American, Hispanic, and Asian populations are less likely to exhibit elevated p-tau217 levels, which correspond to amyloid accumulation, compared to non-Hispanic white individuals. This discrepancy suggests that these underrepresented groups might be less frequently identified as eligible for amyloid-targeting treatments, such as the drug lecanemab, which aims to clear amyloid from the brain.

The study analyzed data from over 6,400 adults aged 55 to 80 across 75 sites nationwide, comparing blood test results and PET scan data. Interestingly, while blood tests showed lower levels of amyloid in certain populations, PET scans confirmed that the same individuals might still exhibit amyloid buildup. This raises important questions about the progression of Alzheimer's in diverse groups and whether amyloid is the primary driver of the disease in all populations.

Furthermore, the research points to potential variations in disease development, emphasizing the need for tailored approaches in diagnosis and treatment. The underrepresentation of high-risk groups in trials highlights the importance of considering sociodemographic and genetic factors in future Alzheimer's research.

The findings have significant implications for expanding participation in prevention trials and developing inclusive therapies. As blood-based biomarkers like p-tau217 become more widespread, they offer a less invasive and more accessible method for early diagnosis and risk assessment. The ongoing exploration aims to understand why some populations show lower amyloid levels and to determine other factors that may influence dementia risk.

Future studies plan to include a broader international cohort, collecting longitudinal data on various blood markers to better understand preventive strategies and disease trajectories in diverse populations. This effort will be crucial in addressing health disparities and ensuring that Alzheimer's treatments are effective for all demographic groups.

Source: https://medicalxpress.com/news/2025-09-blood-biomarkers-alzheimer-disease-trial.html