The study is testing a new study drug in healthy normal weight Japanese and Caucasian participants after a single dose. The aim of this study is to see if the new medicine is safe and how it works in the participants body. Oral monlunabant is a new medicine which cannot be prescribed by doctors but has previously been tested in humans. The participant will either get monlunabant or placebo or a combination of both. Which treatment the participant get is decided by chance. The study will last for about 49 days in total.

Inclusion Criteria:

• Male.
• Age 18-55 years (both inclusive) at the time of signing the informed consent.
• Considered eligible based on the medical history, physical examination, and the results of vital signs, electrocardiogram and clinical laboratory tests performed during the screening visit, as judged by the investigator.
• For Japanese participants, both parents of Japanese descent and both paternal and maternal grandparents of Japanese descent.
• For Caucasian participants, self-reported European descent or white Latin-American descent.
• BMI 18.5-24.9 kg/m^2 (both inclusive) at screening.

Exclusion Criteria:

• Known or suspected hypersensitivity to study intervention(s) or related products.
• Previous randomisation in this study.
• Previous rescreening for this study.
• History of Major Depressive Disorder within the last 2 years from screening.
• Presence or history of any psychiatric disorders (e.g., schizophrenia, bipolar disorder, eating disorders, depression, and anxiety) as judged by the investigator.
• Suicidal ideation corresponding to type 4 or 5 or suicidal behaviour on the Columbia-Suicide Severity Rating Scale (C-SSRS) as assessed at screening or any history of suicidal attempts.
• A Patient Health Questionnaire 9 (PHQ-9) score greater than 9 as assessed at screening.

According to the Novo Nordisk disclosure commitment on novonordisk-trials.com

Sponsor staff involved in the clinical trial is masked according to company standard procedures