Brain HealthNew Alzheimer's Antibody Shows Fewer Blood Vessel Bindings Than Lecanemab
Amyloid-targeting antibodies are a cornerstone of emerging Alzheimer's treatment, but a serious side effect called ARIA — involving brain swelling or bleeding — limits their use. Researchers compared lecanemab (FDA-approved) and ACU193 (sabirnetug, in clinical trials) by applying both antibodies to mouse brain tissue and measuring where each one binds. Lecanemab bound more extensively to cortical plaques and cerebellar blood vessels than ACU193, and covered a larger portion of total amyloid signal. Since vascular binding is thought to trigger ARIA, ACU193's lower vascular attachment may translate to a better safety profile. The study also found that tissue fixation time significantly affected how antibodies interact with amyloid, highlighting how lab protocol choices can influence results. These findings offer a molecular-level explanation for why different Alzheimer's antibodies carry different ARIA risks in patients.
