Developments in Blood Biomarker Testing for Alzheimer Disease, Discussion with Anthony Sireci, MD

Nino Sireci, MD, senior vice president for clinical biomarkers, laboratories, and diagnostics, at Eli Lilly, discussed advances and clinical implications of blood-based biomarker testing for Alzheimer disease. Over the past decade, biomarker development has progressed from cerebrospinal fluid (CSF) assays for amyloid-β and tau to blood-based phosphorylated tau measurements, culminating in recent US Food and Drug Administration approval of plasma Aβ42/40 assays.¹ These advances, along with guidelines and favorable testing reimbursement structures, have positioned blood biomarkers as a practical diagnostic tool, he said.

Sireci emphasized that, while positron emission tomography and CSF testing remain standard currently, they are invasive, costly, and logistically complex. Blood biomarkers offer a less invasive, scalable option that may shorten the average 3-year delay patients face in receiving an Alzheimer disease diagnosis.² Currently recommended for use in secondary care (eg, neurology or memory clinics), blood assays may ultimately facilitate triage in primary care by helping physicians determine which patients with cognitive impairment should be referred for confirmatory testing and specialty care.

Despite strong analytic performance relative to amyloid positron emission tomography, adoption is still limited. Sireci highlighted the need for physician and patient education and broader advocacy to ensure appropriate access. Lessons from oncology biomarker implementation underscore the importance of routine integration into clinical care. Ultimately, earlier and more efficient diagnosis using blood biomarkers may improve patient outcomes by enabling timely initiation of disease-modifying therapies, lifestyle interventions, and comprehensive care planning, Sireci noted.

Dr Sireci is the senior vice president for clinical biomarkers, laboratories, and diagnostics at Eli Lilly and Company. He is highly involved in Alzheimer diagnostics and a driving force behind Lilly’s pioneering work in blood biomarker testing and early detection

References

1. FDA clears first blood test used in diagnosing Alzheimer’s disease. US Food and Drug Administration. Press release. May 16, 2025. Accessed September 26, 2025. https://www.fda.gov/news-events/press-announcements/fda-clears-first-blood-test-used-diagnosing-alzheimers-disease

2. Pelc C. Dementia may take 3.5 years to diagnose after symptoms begin, but why? Medical News Today. July 30, 2025. Accessed September 26, 2025. https://www.medicalnewstoday.com/articles/dementia-takes-3-5-years-diagnosis-after-symptoms-begin-but-why