Longitudinal Evaluation of [18F]GTP1 as a PET Radioligand for Imaging Tau in the Brain of Participants With Alzheimer's Disease Compared to Healthy Participants

Inclusion Criteria

• •For All Participants:
• •\- Availability of a study partner who, in the investigator's judgment, has frequent and sufficient contact with the participant and is able to provide accurate information regarding the participant's cognitive and functional abilities, agrees to accompany the participant and provide information at visits
• •For Healthy Participants:
• •Healthy with no clinically relevant finding on physical examination at screening and upon reporting for the Baseline \[18F\]GTP1 imaging visit
• •Have no cognitive complaint
• •Have a Clinical Dementia Rating Scale (CDR) global score = 0
• •Have a Mini-Mental State Examination (MMSE) score of 28-30
• •For Participants With a Diagnosis of AD:
• •Participants with mild or moderate AD must meet National Institute on Aging - Alzheimer's Association (NIA-AA) core clinical criteria for probable AD dementia, with an amnestic presentation
• •Participants with prodromal AD must meet NIA-AA core clinical criteria for mild cognitive impairment (MCI)
• •Have screening \[18F\]florbetapir PET imaging demonstrating amyloid binding based on qualitative visual read