C2N Diagnostics’ study results show that blood biomarkers included in the Precivity blood test help increase the accuracy of amyloid positron emission tomography (PET) classification in pre-clinical Alzheimer's disease.

The study was published in the Alzheimer’s Association journal, Alzheimer’s & Dementia. The study collected the biomarker data for the clinical trial for Eisai and Biogen’s Leqembi (lecanemab).

The biomarkers under evaluation included the well-established amyloid plaque biomarker, Aβ42/Aβ40, and tau protein biomarkers p-tau217, np-tau217, p-tau181, and np-tau181. Tau is a microtubule-associated protein that plays a key role in Alzheimer’s disease pathology.

There are currently 76 active Alzheimer’s in vitro diagnostic (IVD devices) in development, with ten devices currently undergoing clinical trials, as per GlobalData analysis.

“The cost and burden for researchers and research volunteers for studies into Alzheimer’s disease continues to rise. Any opportunity to streamline the recruitment and enrolment process is helpful given this scenario,” said C2N’s CEO and president Dr Joel Braunstein.

“The blood biomarkers with the highest performance in the study are the biomarkers highlighted in the Precivity blood tests, demonstrating the application of these biomarkers for important research purposes. In addition, healthcare specialists are currently using these biomarkers in our Precivity blood tests to help in the clinical evaluation of patients aged 55 years and older with concerns of cognitive impairment.”

The study evaluated 1,080 baseline plasma samples from the participants who were recruited and screened for enrolment into the Phase III Leqembi trial (NCT04468659). Of all the participants, 340 had positive PET scan findings (defined as Centiloid scale > 20, a standardised amyloid PET measurement).

For the evaluated biomarker, plasma p-tau217/np-tau217 had the highest accuracy followed Aβ42/Aβ40 and p-tau181/np-tau181 for identifying amyloid PET status. Each of the biomarker ratios for the p-tau217, Aβ42, and p-tau181 were more robust in identifying amyloid PET status, compared to their individual absolute concentration values.

The researchers wrote that “including plasma p-tau217/np-tau217, along with Aβ42/Aβ40 in predictive algorithms, may streamline screening preclinical individuals into anti-amyloid clinical trials”.