The first blood test for Alzheimer’s has been given the green light in the United States, paving the way for earlier treatment with newly approved drugs that slow the progression of the devastating neurological disease.
The test, developed by Fujirebio Diagnostics, measures the ratio of two proteins in the blood. The ratio is correlated with amyloid plaques in the brain – a hallmark of Alzheimer’s that, until now, has been detected only through brain scans or spinal fluid analysis.
“Alzheimer’s disease affects more people than breast cancer and prostate cancer combined,” said US Food and Drug Administration (FDA) Commissioner Marty Makary.
There are currently two FDA-approved treatments for Alzheimer’s: lecanemab and donanemab, which target amyloid plaque and have been shown to modestly slow cognitive decline, though they do not cure the disease.
Advocates for the intravenous antibody therapies, including many neurologists, say they can offer patients a few additional months of independence, and are likely to be more effective if started earlier in the disease’s course.
In clinical studies, the blood test produced results largely in line with positron emission tomography (PET) brain scans and spinal fluid analysis.
“This clearance is an important step for Alzheimer’s diagnosis, making it easier and potentially more accessible for US patients earlier in the disease,” said Michelle Tarver of the FDA’s Centre for Devices and Radiological Health.
The test is authorised for use in clinical settings for patients showing signs of cognitive decline, and results must be interpreted alongside other clinical information.
See more from MedicalBrief archives:
A prognostic Alzheimer’s disease blood test in the symptom-free stage — 6-year study
New blood test shows ‘remarkable’ promise in the diagnosis of Alzheimer’s