A Study to Investigate Safety and Tolerability, Pharmacokinetics and Pharmacodynamics of JNJ-55375515 in Healthy Male Participants

A 2-Part, Randomized, Placebo-controlled, Double-blind, Single Ascending Dose Study to Investigate Safety and Tolerability, Pharmacokinetics and Pharmacodynamics of JNJ-55375515 in Healthy Male Subjects

The purpose of this study is to assess safety and tolerability of day-time and night-time dosing of JNJ-55375515 in healthy male participants.

Inclusion Criteria:

• Body Mass Index (BMI) between 18 and 30 kilogram / square meter (kg/m^2) inclusive (BMI=weight/height^2)
• Participant must be healthy based on clinical laboratory tests performed at screening. If the results of the serum chemistry panel, hematology, coagulation or urinalysis are outside the normal reference ranges, retesting of an abnormal lab value (s) that may lead to exclusion will be allowed once during the screening phase. It is expected that laboratory values will generally be within the normal range for the laboratory, though minor deviations, which are not considered to be of clinical significance to the investigator, are acceptable
• Participant must be healthy based on physical and neurological examination, medical history, vital signs, and 12-lead Electrocardiography (ECG) [including QTcF less than or equal to (<=) 450 millisecond (msec)] performed at screening, admission to the clinical unit and pre dose on Day 1 of Period 1. Abnormalities, which are not considered to be of clinical significance by the investigator, are acceptable. The presence of Left Bundle Branch Block (LBBB), AV Block (second degree or higher), or a permanent pacemaker or implantable cardioverter defibrillator [ICD] will lead to exclusion
• Non-smoker (not smoked for 3 months prior to screening)
• During the study and for a minimum of 1 spermatogenesis cycle (defined as approximately 90 days) after receiving the last dose of study drug, in addition to the highly effective method of contraception, a man who is sexually active with a woman of childbearing potential must agree to use a barrier method of contraception (for example, condom with spermicidal foam/gel/film/cream/suppository); who is sexually active with a woman who is pregnant must use a condom; must agree not to donate sperm

Exclusion Criteria:

• History of or current significant medical illness including (but not limited to psychotic, bipolar, major depressive, or anxiety disorder)
• Cardiac arrhythmias or other cardiac disease, hematological disease, lipid abnormalities, respiratory disease, diabetes mellitus, renal or hepatic insufficiency, thyroid disease, Parkinson's disease, infection, or any other illness that the Investigator considers should exclude the participant
• Serology positive for hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV) antibodies or human immunodeficiency virus (HIV) antibodies
• Participant has a history of or current vestibular disease including (but not limited to) Meniere's disease, benign paroxysmal positional vertigo (BPPV), vestibular neuronitis, vestibular schwannoma or vestibular migraine
• Only for part 2: Has a current diagnosis or history of narcolepsy, central sleep apnea, sleep related hypoventilation, circadian rhythm sleep-wake disorders, substance/medication induced sleep disorder or parasomnias (non-rapid eye movement sleep arousal disorders, nightmare disorder, rapid eye movement sleep behavior disorder); obstructive sleep apnea/hypopnea (apnea/hypopnea index greater than (>)10) or restless legs syndrome (periodic leg movements with arousal index >15); night-shift worker or significantly shifted diurnal activity pattern (it is expected that eligible participant normally wake up between 6:00 am - 8:00 am and go to bed between 10:00 pm - 12:00 am); usual bedtime outside of 10:00 pm and 12:00 am and taking, on average, less than 6 hours or more than 9 hours of bed rest