This is a study to assess the food effect of TS-142 preliminary market formulation tablet in healthy subjects

Inclusion Criteria:

1. Japanese male who are aged 18 years or older but less than 40 years at the time of informed consent
2. Body Mass Index (BMI) of 18.5 or more and less than 25.0 at the screening test
3. Subjects who are judged by the investigators as an eligible for the clinical trial participation based on the screening tests and the tests conducted at treatment period 1.

Other protocol defined inclusion criteria could apply.

Exclusion Criteria:

1. Subjects who are judged to have any disease by the principal investigator or sub-investigator and are not considered healthy
2. Subjects who have any unsuitable medical history for participation in this study, including respiratory, cardiovascular, gastrointestinal, hepatic, renal, urological, endocrinological, metabolic, hematologic, immunologic, dermatological, neurological, or psychiatric diseases
3. Subjects who have any medical histories including sleep-associated symptoms, narcolepsy-like symptoms, suicidal ideation, or suicidal attempts

Other protocol defined exclusion criteria could apply.