Additional Study Information: This study is for patients with Alzheimer's Disease. Alzheimers disease is a disorder characterized by progressive loss of memory, thinking, and behavior. An earlier study in patients having mild to moderate Alzheimers disease has demonstrated more pronounced benefit of treatment with azeliragon among participants with mild disease than among participants with moderate disease The purpose of this study is to learn how well azeliragon works and how safe study medication is compared to placebo in participants having mild Alzheimers disease. A placebo is an inactive material that looks like the study medication but does not contain any active study medication. Researchers use a placebo to see if the study medication works better or is safer than not taking anything.