BAY 76-7171

BAY 76-7171 is a small molecule inhibitor of glycogen synthase kinase 3 (GSK-3), targeting both the alpha (GSK-3α) and beta (GSK-3β) isoforms. Developed by Bayer, the compound was primarily investigated for its potential in treating neurodegenerative and psychiatric disorders, most notably Alzheimer's disease and bipolar disorder. GSK-3 plays a critical role in the phosphorylation of tau protein; therefore, its inhibition is hypothesized to reduce the formation of neurofibrillary tangles, a hallmark of Alzheimer's pathology. Additionally, GSK-3 inhibition mimics some effects of lithium, suggesting utility in mood stabilization. Clinical development for these indications has largely been discontinued following early-phase evaluations.