B-025 Evaluation of Bias Between Alzheimer’s Disease Blood-Based Biomarkers Assays and Their Concordance With Amyloid-PET on the Fujirebio Lumipulse and Quanterix Simoa Platforms

Abstract Background Blood-based biomarkers (BBBs) are a growing area of study for improving Alzheimer’s disease (AD) clinical evaluation. BBBs have been demonstrated to correlate with AD CSF as well neuroimaging results assessment amyloid pathology. Currently may be used screening tool patient selection in trials, and alongside more characterized like amyloid-PET markers evaluation individuals presenting cognitive impairment. A comparative several assays was performed assess bias between two platforms, correlation Methods The included 146 plasma samples from 112 cognitively normal (CN), 34 mild impairment (MCI) or dementia individuals. Plasma Aβ42, Aβ40, pTau181 concentrations were obtained using the Fujirebio Lumipulse Quanterix Simoa immunoassays. Assay comparison Aβ42/Aβ40 ratio, pTau181, pTau181/Aβ42 ratio Passing-Bablok regression slopes obtained. Amyloid-PET Pittsburg Compound B, standard uptake value (SUVR) 1.48 classify status. In CN group, 69 negative, 43 positive. MCI/AD 8 negative 26 Spearman’s rank coefficient (rho) determine each SUVRs. Results Between (y) (x) assays, measured Aβ42 Aβ40 showed large y = 5.23x − 14.25, 4.42x 264.87, respectively. moderate strong observed rho values 0.641 (P < 0.0001), 0.498 corrected this 0.96x + 0.03 0.509 0.0001). little methods 0.92x 0.48, 0.592 However, driven mostly by differences 0.27x 0.04 0.574 assay correlated SUVR yielded coefficients AB42/40 −0.219 0.079), 0.380 0.466 −0.551 0.370 0.391 Conclusion This demonstrates that some differ significantly manufacturers. Little determinations evaluated platforms; however, significant ratio. platform stronger SUVR, while better similar SUVR. Bias preclude generalization performance platforms.