A path has opened to check for Alzheimer's disease with a simple blood test at neighborhood clinics. With Alzheimer's testing, which had previously required brain imaging or cerebrospinal fluid tests, now possible with blood, diagnostic access is expected to improve.
Reuters reported on the 24th (local time) that the U.S. Food and Drug Administration (FDA) approved Elecsys Phospho-Tau 217 (pTau217), an Alzheimer's blood test co-developed by Roche Diagnostics, a subsidiary of Switzerland's Roche, and Eli Lilly and Company. The test was approved in Europe in May and in Japan this month, and has now been cleared in the United States.
Alzheimer's disease is a representative degenerative brain disorder that occurs when amyloid-beta and tau proteins abnormally accumulate in the brain.
Elecsys pTau217 is an in vitro diagnostic test that measures phosphorylated tau protein in the blood to determine whether amyloid plaques have accumulated in the brain. Based on the results, it can distinguish patients with a high likelihood of Alzheimer's disease from those with a low likelihood and be used to identify who needs additional positron emission tomography (PET) or cerebrospinal fluid testing.
Until now, PET scans or cerebrospinal fluid tests were mainly used to check for amyloid-beta accumulation. The testing expense was high and the procedures were complicated, placing a heavy burden on patients.
By contrast, Elecsys pTau217 can be performed with a relatively simple blood draw. It can be used in primary care settings and is available for patients 55 and older with cognitive decline symptoms.
Roche described it as "the first FDA-authorized single biomarker blood test to aid in confirming and ruling out amyloid pathology in both primary care and specialized settings."
Alzheimer's disease is the most common degenerative brain disorder that causes dementia. It develops gradually, with cognitive functions, including memory, declining progressively. There is currently no fundamental cure, but as treatments that slow symptom progression are developed, the importance of early diagnosis is growing.
Neurologist Gerard Brochu of Indiana University said, "The existing approach was hard for many patients to access, but as biomarker testing advances, access to Alzheimer's testing is expanding."