Spatial patterns of amyloid clearance after donanemab: A preliminary 12‐month real‐world amyloid PET study in Japanese patients with early Alzheimer's disease
Yuki Kujuro, Marina Saito, Manami Maruko, Emi Qian, Hidefumi Koh, Hitoshi Katai, Hidenori HattoriAbstract
Introduction
The regional pattern of amyloid clearance during donanemab treatment in routine practice is poorly characterized.
Methods
We analyzed amyloid positron emission tomography (Centiloid, regional standardized uptake value ratio, visual reads) at baseline and 12 months in 18 donanemab‐treated patients with early Alzheimer's disease.
Results
Clearance was near‐complete (removal 96%; 72% visually negative, i.e., full treatment‐related amyloid clearance), although lower in the 2 early‐onset (78%) than the 16 late‐onset patients (98%). Higher baseline burden and older age predicted greater clearance ( r = 0.88, P < .001; r = 0.60, P = .009, respectively). This held regionally ( r = 0.82–0.91, all P < .001), with the posterior cingulate and precuneus clearing first. Clearance was independent of medial temporal atrophy and unrelated to 12‐month cognitive change.
Discussion
Donanemab cleared regional amyloid in proportion to its baseline distribution, with deposition‐heavy regions clearing first and the temporal cortex retaining residual signal, independent of neurodegenerative stage and unrelated to short‐term cognition.