To assess the safety and tolerability of ascending single oral doses of SAM-315, an investigational drug, in healthy adult subjects. To obtain a preliminary pharmacokinetic (PK) and pharmacodynamic (PD) profiles of SAM-315 in healthy subjects and to evaluate the effect of a high-fat meal on the PK of SAM-315, an investigation drug, administered to healthy adult subjects.

Inclusion criteria:

• Men and women of nonchildbearing potential aged 18 to 45 years
• Body mass index in the range of 18 to 30 kg/m2 and body weight ≥50 kg.
• Healthy as determined by the investigator on the basis of medical history, physical examination, clinical laboratory test results, vital signs, and digital 12-lead electrocardiogram (ECG). Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine levels must be within the upper limit of normal for eligibility.

Exclusion criteria:

• Any significant cardiovascular, hepatic, renal, respiratory, gastrointestinal, endocrine, immunologic, dermatologic, hematologic, neurologic, or psychiatric disease.
• Any clinically important deviation from normal limits in physical examination, vital signs, digital 12-lead ECGs, or clinical laboratory test results.
• Consumption of any caffeine-containing products (e.g., coffee, tea, chocolate, or soda) or alcoholic beverages within 48 hours and, grapefruit, grapefruit-containing products is prohibited 72 hours before study day 1.