Used primarily in the field of medical research, lanabecestat is a beta-secretase (BACE1) inhibitor investigated for treating neurodegenerative diseases, particularly Alzheimer's disease. It aims to reduce amyloid-beta peptide production, implicated in disease progression. Phase 2/3 clinical trials assessed its ability to slow cognitive decline, but development was discontinued in 2018 by AstraZeneca and Eli Lilly due to lack of efficacy and adverse effects including cognitive worsening. It remains available for research into amyloid-related conditions.