This study is for adults who have schizophrenia, a mental health condition that can cause people to see or hear things that aren't there. The study will test if a new medicine called NBI-1117568 helps improve symptoms better than a placebo (a pill with no real medicine). To join, you need to stay in the hospital for the whole study because it's important to watch how the medicine works. You can't take certain other medicines, especially those for schizophrenia, during the study. If you're allergic to NBI-1117568's ingredients or have serious health issues, you can't join. People with a history of substance abuse, except for nicotine or caffeine, or who might harm themselves or others, also cannot participate. The study makes sure everyone is safe and follows the rules carefully.

• Duration: You must stay in the hospital for the entire study.
• Medication: You cannot take other schizophrenia medicines during the study.
• Safety: Participants must not have serious health issues or substance abuse problems.