Study Evaluating Effects of SAM-531 on Sleep Electroencephalogram (EEG) and Quantitative Wake EEG in Healthy Subjects

• Healthy
• Adult

• Drug: SAM-531
  
  dosage form : 0.5 mg and 5 mg capsules 3 different single doses : 1 mg, 3mg and 10 mg of SAM-531
• Other: placebo
  
  placebo
• Drug: Donepezil
  
  dosage form: 5 mg encapsulated tablets one single dose of 5 mg.

• Experimental: 1
  
  Intervention: Drug: SAM-531
• Placebo Comparator: 2
  
  Intervention: Other: placebo
• Active Comparator: 3
  
  Intervention: Drug: Donepezil

Inclusion Criteria:

• Men or women of non-childbearing potential aged 18 to 50 years inclusive on study day 1.
• Body mass index in the range of 18 to 30 kg/m2 and body weight greater than or equal to 50 kg.
• Healthy as determined by the investigator on the basis of medical history, physical examination, clinical laboratory test results, vital sign measurements, and 12-lead electrocardiogram.

Exclusion Criteria:

• Any significant cardiovascular, hepatic, renal, respiratory, gastrointestinal, endocrine, immunologic, dermatologic, neurologic, hematologic, neurologic, or psychiatric disease.
• Clinically significant abnormal standard EEG at screening.
• Consumption of any caffeine-containing products or alcoholic beverages within 48 hours before study day 1.