Symptomatic lobar intracerebral hemorrhage during extended lecanemab treatment: A case report
Year: 2026
Type: article
Study design: Case Report
Abstract: Lecanemab is an anti-amyloid-β protofibril antibody that slows cognitive decline in early Alzheimer's disease. Although amyloid-related imaging abnormalities (ARIA) occur predominantly early in treatment, reports of hemorrhagic events during extended treatment beyond 18 months remain limited. A 77-year-old woman completed a standard 1.5-year lecanemab regimen without ARIA on surveillance MRIs. The day after her 42nd infusion, she acutely developed confusion and incomprehensible speech. MRI revealed a 2.5-cm left parietal subcortical hemorrhage. This case highlights that symptomatic lobar hemorrhage may occur even during extended lecanemab therapy, underscoring the importance of continued safety monitoring during extended treatment.
Institutions: Nippon Life Hospital, The University of Osaka
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: diamond
Award: G5212376297
OpenAlex ID: W7212033338