History repeats itself: A new trivializing term for a potentially life-threatening side effect of antibody Alzheimer's disease therapy.

The term "amyloid-removal-related pseudo-atrophy" has recently been proposed for the accelerated brain volume loss caused by anti-Alzheimer's antibody therapies, although most trials seem to neglect it. As with 'amyloid-related imaging abnormalities' (ARIAs), this is downplaying yet another side effect of passive antibody therapy that cannot be justified until its impact on brain function is fully understood. ARIAs and accelerated volume loss are likely due to antibody-induced brain tissue damage, making amyloid-PET imaging an unreliable indicator of amyloid removal. Therefore, approval of antibody therapy based on presumed amyloid removal should be suspended until this looming possibility has been fully investigated.