BACE1 and Alzheimer disease: Drugs that reduce Aβ levels, including γ-secretase inhibitors/modulators, BACE-1 inhibitors that reduce Aβ production, and active/passive immune agents that prevent Aβ aggregation or promote Aβ clearance (e.g., antibodies to Aβ protein), did not improve cognitive function in patients with AD in clinical trials (Huang et al., 2020).