A Study to Investigate the Safety, Tolerability, and Pharmacokinetics of JNJ-55308942 in Healthy Male and Female Participants

A Double-Blind, Placebo-Controlled, Randomized Single and Multiple Ascending Dose Study to Investigate the Safety, Tolerability, and Pharmacokinetics of JNJ-55308942 in Healthy Male and Female Subjects

The purpose of this study is to assess the safety, tolerability, and pharmacokinetics (PK) of JNJ-55308942 in healthy participants after administration of single and multiple oral doses.

Inclusion Criteria:

• Participant must have a body mass index (BMI) between 18.0 and 30.0 kilogram per meter square (kg/m^2) (BMI = weight [kg] / height [m]^2), and a body weight of not less than 50 kilogram (kg)
• Participant must be healthy on the basis of physical examination, neurological examination, medical history, vital signs, and 12 lead (electrocardiogram) ECG, and peripheral capillary oxygen saturation [(SpO2) greater than or equal to (>=) 97 percent] performed at Screening and Day -1
• Participant must be healthy on the basis of clinical laboratory tests performed at Screening and Day -1. If the results of the serum chemistry panel, coagulation, hematology, or urinalysis are outside the normal reference ranges, the participant may be included only if the investigator judges the abnormalities or deviations from normal to be not clinically significant. This determination must be recorded in the participant's source documents and initialed by the investigator
• Female participants must not be of childbearing potential by fulfilling 1 of the criteria: a) be over 45 years of age with no menses for 12 months without an alternative medical cause, with screening follicle stimulating hormone (FSH) levels of greater than (>) 40 International Unit per Liter (IU/L) or milli-International Unit per milliliter (mIU/mL). b) be permanently surgically sterile. Permanent surgical sterilization methods include hysterectomy, bilateral salpingectomy, bilateral tubal occlusion/ligation procedures, and bilateral oophorectomy. Documentation of FSH levels is not required in the case of surgical sterility
• Female participants must have a negative serum pregnancy (Beta -human chorionic gonadotropin [Beta -hCG]) test at screening and a negative urine pregnancy test on Day -1

Exclusion Criteria:

• Participant has current, or history of, clinically significant medical illness including, but not limited to, liver or renal insufficiency, significant cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, hematologic, rheumatologic, psychiatric, or metabolic disturbances
• Participant has a history of abnormal bleeding or clotting, or disorder of fibrinogen (example, dysfibrinogenemia, hypofibrinogenemia)
• Participant has history of malignancy within 5 years before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix, or malignancy that in the opinion of the Investigator, with concurrence with the Sponsor's medical monitor, is considered cured with minimal risk of recurrence)
• Participant has received an investigational drug (including investigational vaccines) or used an invasive investigational medical device within 1 month or within a period of less than 10 times the drug's half-life, whichever is longer, before the planned first dose of study drug, or is currently enrolled in another investigational study
• Participant has a history of drug or alcohol abuse according to Diagnostic and Statistical Manual of Mental Disorders (5th edition) (DSM-V) criteria within 5 years before Screening or positive test result(s) for alcohol or drugs of abuse (including barbiturates, opiates, cocaine, cannabinoids, amphetamines, ecstasy, phencyclidine, tricyclic antidepressants, and benzodiazepines) at Screening