Plasma P‐tau217 for detecting amyloid clearance after donanemab in Alzheimer's disease
Emily C. Collins, Ming Lu, Rose Beck, James Hendrix, Michael E. Hodsdon, Oskar HanssonAbstract
INTRODUCTION
This analysis of the phase 3 TRAILBLAZER‐ALZ 2 trial examined whether plasma tau protein phosphorylated at threonine 217 (p‐tau217) level can reliably monitor treatment‐related amyloid clearance (TRAC) after donanemab treatment in early symptomatic Alzheimer's disease (AD).
METHODS
Amyloid positron emission tomography (PET) and plasma p‐tau217 levels were assessed at baseline and longitudinally during study treatment. The diagnostic performance of p‐tau217 in detecting post‐treatment TRAC (< 24.1 Centiloids [CL]) was evaluated by receiver operating characteristic (ROC) analysis.
RESULTS
Plasma p‐tau217 showed suboptimal performance in detecting TRAC by PET in donanemab‐treated participants ( N = 830), with an area under the ROC curve of 0.61 at 52 weeks.
DISCUSSION
Despite reductions in plasma p‐tau217 with donanemab treatment, this biomarker cannot currently be used to accurately detect TRAC by PET (< 24.1 CL) in individuals with early symptomatic AD.