Brain Imaging Study in Subjects With Alzheimer Disease in Comparison to Healthy Subjects

The overall research questions to be addressed by this protocol are as follows:

- To assess the dynamic uptake and washout of (123I) MNI-168, a potential imaging
biomarker for β-amyloid burden in brain, using single photon emission computed
tomography (SPECT) in Alzheimer's (AD) subjects and similarly aged and gender matched
healthy controls.

- To perform blood metabolite characterization of (123I) MNI-168 in healthy and AD
subjects to determine the metabolic fate and nature of metabolites in assessment of
(123I) MNI-168 as a single photon computed tomography (SPECT) brain imaging agent.

- To acquire initial safety data following injection of (123I) MNI-168.

- Obtain test/retest reproducibility information in AD subjects with (123I) MNI-168 based
on initial studies.

Inclusion Criteria:

- Subjects who have a clinical diagnosis of AD will be recruited for this study

- The participant is 50 years or older

- Written informed consent is obtained

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

- Subjects will have a clinical dementia rating (CDR) assessment score of ≥ 0.5 and <
2.0

- Modified Hachinski Ischemia Scale score of ≤ 4

- For females, non-child bearing potential or negative urine and blood pregnancy test on
day of 123-I MNI-168 injection

Exclusion Criteria:

- The subject has signs or symptoms of another neurodegenerative disease including
Parkinson's disease, diffuse Lewy body dementia, or history of significant
cerebrovascular disease

- The subject has 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 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

- Clinically significant MRI evidence of vascular disease or alternative neurologic
disorder

- Pregnancy