Blood test boosts diagnostic accuracy for Alzheimer’s by calculating amyloid probability

C₂N Diagnostics released the PrecivityAD2 blood test, which uses positron emission tomography scans and cerebrospinal fluid tests to assist in accurate diagnosis for those presenting with signs or symptoms of Alzheimer’s disease.

According to a company release, in a clinical validation study involving two independent cohorts of 583 patients with cognitive impairment using amyloid positron emission tomography (PET) as a reference, the PrecivityAD2 blood test achieved 0.94 area under the curve and 88% diagnostic accuracy.

The mechanism for PrecivityAD2’s accuracy simultaneously quantifies specific plasma amyloid beta and tau peptide concentrations to calculate ratios for biomarkers A42/40 and p-tau217/np-tau217, which are combined into an algorithm that calculates an Amyloid Probability Score 2, per the release. That score, a numerical value ranging from 0 to 100, determines whether a patient is positive (high likelihood) or negative (low likelihood) for the presence of brain amyloid plaques by amyloid PET scan.

Both the PrecivityAD2 and PrecivityAD blood tests are intended for use in patients aged 55 and older who present with signs or symptoms of either mild cognitive impairment or dementia who are being evaluated for AD or dementia.

“We believe the PrecivityAD2 test represents the next generation in blood biomarker tests and will help establish a new standard in Alzheimer’s disease diagnosis,” Joel Braunstein, MD, MBA, president and CEO of C₂N Diagnostics, stated in the release. “We believe the test addresses a major unmet need for an accurate, safe, noninvasive, and accessible alternative to amyloid PET scans and lumbar punctures.”