A Double-Blind, Placebo-Controlled, Dose Ranging Study of Xanamem® in Healthy Elderly Volunteers

1. Male or female aged 50 to 80

2. Body mass index 17.5 to < 35 kg/m2, inclusive at the time of screening

3. Mini-Mental State Score of ≥ 25 points at screening

4. Must provide written informed consent

1. Abnormalities in vital signs at screening or baseline

2. Clinically significant abnormal hematology or biochemistry values, as determined by the investigator at screening and/or baseline.

3. Previous clinically significant systemic illness or infection within the past 4 weeks prior to screening or baseline, as determined by the investigator

4. Clinically significant ECG abnormalities

5. Use of tobacco- or nicotine-containing products in the past month or unwillingness to abstain during study participation

6. Participation in another clinical study of a drug or device

7. Known allergy to the study drug (Xanamem®) or any of the excipients

8. Subjects who are likely to be unable to comply with the study schedule and/ or subjects with an inability to communicate well with the investigator

9. Positive testing for human immunodeficiency virus (HIV), hepatitis B surface antigen, or hepatitis C antibodies at screening

10. Subjects with a history of drug abuse or addiction in the past 5 years.

11. Evidence of alcohol abuse (defined as greater than 21 standard units per week for males and greater than 14 standard units per week for females)