The purpose of this study is to evaluate the safety and tolerability of multiple ascending doses of ORM-12741.

The purpose is to evaluate the safety, tolerability and pharmacokinetics of escalating multiple doses of ORM-12741 in healthy volunteers.

Inclusion Criteria:

• Good general health ascertained by detailed medical history and physical examinations.
• Males between 18 and 45 years (inclusive).
• Body mass index (BMI) between 18-30 kg/m2 inclusive (BMI = weight/height2).
• Weight 55-100 kg (inclusive).

Exclusion Criteria:

• Evidence of clinically significant cardiovascular, renal, hepatic, haematological, gastro-intestinal, pulmonary, metabolic-endocrine, neurological, urogenital or psychiatric disease as judged by the investigator.
• Any condition requiring regular concomitant medication including herbal products or likely to need any concomitant medication during the study.
• Susceptibility to severe allergic reactions.
• Regular consumption of more than 14 units of alcohol per week (1 unit = 4 cl spirits, about 13 g of alcohol).
• Current use of nicotine-containing products more than 5 cigarettes or equivalent/day.
• Inability to refrain from using nicotine-containing products during the stay at the study centre.
• Inability to refrain from consuming caffeine-containing beverages during the stay at the study centre e.g. propensity in getting headache when refraining from caffeine-containing beverages.
• Blood donation or loss of significant amount of blood within 3 months prior to the screening visit.
• Abnormal finding in ECG, vital signs, laboratory tests or physical examination.
• Intake of an investigational compound within 3 months prior to the start of this study or earlier participation in a clinical study with ORM-12741