The FDA has approved a new subcutaneous formulation of Eisai and Biogen's Alzheimer’s drug Leqembi, marking an incremental step in the effort to compete with existing treatments like Eli Lilly's Kisunla. Meanwhile, Prothena reported Phase 1 data for its amyloid-targeting candidate PRX012, noting a high incidence of ARIA-E events which raises safety concerns. These developments underscore ongoing advancements and challenges in Alzheimer’s therapeutic pipelines.