Evaluation of [18F]MNI-777 PET as a Marker of Tau Pathology in Subjects With Tauopathies Compared to Healthy Subjects

Inclusion Criteria:

For all subjects:

- Written informed consent or assent is obtained.

- Willing and able to cooperate with study procedures.

- For females, non-child bearing potential or negative urine pregnancy test on day of
[18F]MNI-777 injection.

Alzheimer Disease subjects:

- The participant is 50 years or older.

- Participants have a clinical diagnosis of Alzheimer's disease based on National
Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease
and Related Disorders Association (NINCDS/ADRDA) criteria (McKann, 1984)

- Modified Hachinski Ischemia Scale score of ≤ 4.

Parkinson's Disease subjects:

- The participant is 30 years or older.

- Participants have a clinical diagnosis of PD based on the UK Brain Bank Criteria
(Hughes, et al., 1982).

- The duration of diagnosis of PD is <20 years prior to the imaging visit

- PD subjects must be on stable doses of medications for a period of at least 30 days
prior to the imaging visit.

- Treatment with dopamine replacement therapies or other symptomatic therapies for PD
is permitted; however, subjects must be on a stable dose of medications 30 days prior
to the imaging visit.

Progressive Supranuclear Palsy subjects:

- The participant is 30 years or older.

- Participants have a clinical diagnosis of PSP based on National Institute of
Neurological Disorders and Stroke/ (NINDS) and the Society for PSP (SPSP) criteria
(Litvan, et al. 1996).

Chronic Traumatic Encephalopathy subjects:

- The participant is 18 years or older.

- Subjects with a diagnosis of probable CTE based on a prior history of repetitive
brain trauma and at least one concussion, and a current mood disorder (depression,
apathy, irritability, suicidal ideation), cognitive symptoms (memory loss, impaired
executive function) or behavioral symptoms (disinhibition, aggression and increased
violence) (Jordan, 2013).

Frontal Temporal Dementia/Pick's disease subjects:

- The participant is 50 years or older.

- Participants have a clinical diagnosis of FTD based on consensus for clinical
diagnosis of frontotemporal dementia (Neary, et al., 1998)

Healthy Control subjects:

- The participant is 18 - 85 years old.

- Negative history of neurological or psychiatric illness based on evaluation by a
research physician.

- MMSE score must be 29 or above.

Exclusion Criteria:

All subjects will be excluded from participation for the following reasons:

- The subject has a clinically significant abnormal laboratory value and/or clinically
significant unstable medical or psychiatric illness.

- The subject has any disorder that may interfere with drug absorption distribution,
metabolism, or excretion (including gastrointestinal surgery).

- The subject has evidence of a structural lesion on MRI that may interfere with
interpretation of PET imaging.

- The subject has evidence of clinically significant gastrointestinal, cardiovascular,
hepatic, renal, hematological, neoplastic, endocrine, neurological, immunodeficiency,
pulmonary, or other disorder or disease.

- The subject has participated in another clinical study within the previous 30 days.

- Pregnancy or women who are nursing or breastfeeding