A Phase 0, Open Label, Multi-Center, Exploratory and Safety Study of [F-18]T808

You may be eligible if

• Low Probability for AD Participants (Group 1)
• Participant is of any race/gender/ethnicity who has reached his or her 55th birthday at the time of informed consent.
• Participant provides written informed consent Participant is capable of complying with study procedures
• Participant is capable of communicating with study personnel
• Participant understands and speaks English
• Participant has at least an 8th Grade education
• In the Investigator"s opinion, participant has a low probability of being currently positive for AD as determined by a Mini Mental State Examination (MMSE ≥ 28) defined in APPENDIX VI of XXX protocol
• Participant has no significant hepatic or renal disease as defined by previous medical history and lab results are within the following ranges: Total bilirubin within 2x institutional upper limits of normal AST (SGOT) ≤ 2.5 x institutional upper limits of normal ALT (SGPT) ≤ 2.5 x institutional upper limits of normal Creatinine ≤ 2x institutional upper limits of normal BUN within 2x institutional upper limits of normal
• High Probability for AD Participants (Group 2)
• Participant is of any race/gender/ethnicity who has reached his or her 55th birthday at the time of informed consent.
• Participant or participant"s legally acceptable representative provides written informed consent Participant is capable of complying with study procedures
• Participant is capable of communicating with study personnel
• Participant understands and speaks English
• Participant has at least an 8th Grade education In the Investigator"s opinion, \*participant has a high probability of being currently positive for AD that is determined by a Mini Mental State Examination (MMSE \< 17) defined in APPENDIX VI of XXX protocol
• Participant has no significant hepatic or renal disease as defined by previous medical history, and lab results are within the following ranges: Total bilirubin within 2x institutional upper limits of normal AST (SGOT) ≤ 2.5 x institutional upper limits of normal ALT (SGPT) ≤ 2.5 x institutional upper limits of normal Creatinine ≤ 2x institutional upper limits of normal BUN within 2x institutional upper limits of normal