Evaluation of [123I] MNI-308 and SPECT as a Marker of Beta-amyloid Protein Deposition in AD Subjects Compared to HC

General Design and Methods. The underlying goal of this study is to assess 123-I MNI-308 SPECT imaging as a tool to detect ß-amyloid deposition in the brain of AD research participants and age- and gender-matched healthy subjects. All study procedures will be conducted at the Institute for Neurodegenerative Disorders (IND) and Molecular NeuroImaging (MNI) in New Haven, CT. Approximately 10 patients with Alzheimers disease (AD) and 6 healthy controls (within +/- 2 years) will be recruited to participate in this study. Healthy controls will be examined to ensure that there is no evidence of neurodegenerative changes including cognitive decline. An interval of at least 14 days will lapse between dosing in the first four AD subjects. This is intended to provide a longer period for AE assessments. Once complete, absent any serious adverse events in these initial AD subjects, dosing may commence with the remainder of the subjects, including healthy controls. Informed consent will be obtained for all subjects. All subjects will undergo a screening evaluation including baseline clinical laboratory testing, a baseline physical and neurological evaluation and baseline cognitive evaluations. Subjects will be asked to undergo a bolus injection of 123-I MNI-308. Subjects will undergo serial SPECT imaging scans and serial venous plasma sampling for measurement of 123-I MNI-308 in plasma (both protein bound and free) over a period of up to 8 hours. The imaging analyses will be performed by an image-processing specialist who will remain masked to the procedures employed with each imaging acquisition. The primary imaging outcome measure will be the brain regional distribution volumes expressed as a brain tissue to plasma ratio of the radioligand, 123-I MNI-308. Time to the peak uptake and amplitude of the peak uptake will be evaluated for all brain regions and the results for the AD patients and controls will be compared.