Study Overview: This research is looking at the safety and how well an investigational medication works for people with early Alzheimer's Disease (AD) or mild cognitive impairment (MCI) caused by AD. The study aims to see if the investigational medication can slow down memory and thinking problems.

Study Details: You will need to visit the study site several times over a period of time. The study includes a placebo-controlled period and a long-term extension period to check the long-term effects of the investigational medication.

• Time Commitment: Multiple visits over a long period.
• Eligibility: You need to have memory changes for more than 6 months and meet other health criteria.
• Important Considerations: You should not have other serious health conditions, recent stroke, or substance abuse issues.

Note: Participants must be willing to undergo genetic testing and have a study partner who knows them well. Doctors will assess if you qualify.