BACE1 and Alzheimer disease: Unfortunately, BACE1 inhibitors that have undergone advanced phases of clinical trials to date in mild-to-moderate and early/prodromal AD populations have been halted due to futility and/or side effects including signs of mild cognitive worsening at the higher dosage (McDade et al., 2021; Bazzari and Bazzari, 2022; Coimbra et al., 2024; Naidu et al., 2025).