Safety and Tolerability Study With Single Ascending Doses of ORM-12741

Inclusion Criteria: * Good general health ascertained by detailed medical history and physical examinations * Males between 18 and 45 years * Body mass index (BMI) between 18-30 kg/m2 * Weight 55-90 kg Exclusion Criteria: * Evidence of clinically significant cardiovascular, renal, hepatic, haematological, gastro-intestinal, pulmonary, metabolic-endocrine, neurological, urogenital or psychiatric disease * Any condition requiring regular concomitant treatment including herbal products or likely to need any concomitant treatment during the study * Susceptibility to severe allergic reactions * Regular consumption of more than 14 units of alcohol per week * Current use of nicotine-containing products more than 5 cigarettes or equivalent/day * Inability to refrain from using nicotine-containing products during the stay in the study centre * Inability to refrain from consuming caffeine-containing beverages during the stay in the study centre * 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 * Participation in a drug study within 3 months prior to the start of this study