LY2886721 is a potent and selective inhibitor of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), which plays a key role in the production of amyloid-beta peptides. These peptides are central to the formation of amyloid plaques found in the brains of Alzheimer's disease patients. By inhibiting BACE1, LY2886721 was developed to reduce amyloid-beta levels, aiming to slow or modify the progression of Alzheimer's disease. It has been investigated in clinical trials as a potential therapeutic agent for early-stage Alzheimer's, particularly to assess its impact on biomarkers related to amyloid pathology. Despite promising preclinical results, development was discontinued due to safety concerns observed in later stages of clinical testing. Nonetheless, it remains a significant compound in the study of BACE1 inhibitors and their role in neurodegenerative disease research.