About 380 males and females aged 55 to 90 years with psychosis associated with Alzheimer's disease will take part in this worldwide study. This study will be conducted at up to 100 sites in the United States, Canada, France, Germany, Spain and others in approximately 10 countries. The study will test KarXT, a combination of 2 study drugs, xanomeline tartrate and trospium chloride. Xanomeline tartrate stimulates the muscarinic receptors (a receptor in the nervous system) that is involved in cognitive and neurobehavioral functions. Stimulation of these receptors has been shown to effect changes in cognitive performance and promote antipsychotic activity. Trospium chloride is a muscarinic inhibitor that is expected to reduce the negative peripheral (outside the brain) muscarinic side effects of xanomeline tartrate without reducing its intended therapeutic effects in the brain.
The goal of this study is to assess whether KarXT helps in relapse prevention in people with psychosis associated with AD as compared to placebo, see how safe and well accepted KarXT is in people with psychosis associated with AD as compared to placebo, and check what the body does to KarXT and how long does it stay in the body (pharmacokinetics) as compared to placebo.