This study tests a medicine called **emraclidine** to see if it's safe for people aged 65-90, including those with Alzheimer's Disease (AD), a condition that affects memory and thinking skills. The study has two parts: Part A for healthy elderly people and Part B for those with AD. Participants will take emraclidine by mouth in multiple doses.

**Key Points to Consider:**

• The study involves multiple visits over a certain period for health checks and monitoring.
• Participants may receive compensation for their time and travel expenses.
• Potential risks include side effects from the medication, and not all volunteers may be eligible if they have certain health conditions or history.

To join, participants must meet specific health criteria, such as being within a certain weight range and not having certain mental health issues. They should also not have a history of substance abuse or certain other medical conditions. It's important that participants give informed consent, meaning they understand and agree to the study's requirements.