MAPT and Mental deterioration: In January 2023, the FDA approved Lecanemab (Leqembi), another monoclonal antibody developed by Eisai and Biogen, as it has been shown to slow cognitive decline in a robust Phase II clinical trial and decrease amyloid and tau accumulation in patients' brains, with much less incidence of brain swelling or bleeding compared to Aducanumab (van Dyck et al. 2022; Larkin 2023; Reardon 2023).