A Study of Orally Administered JNJ-440 to Evaluate the Safety, Tolerability, and Pharmacokinetics After Single Ascending Doses Including Food Effect Evaluation; After Multi-Day Dosing in Healthy Participants; and After Multiple (Ascending) Doses in Participants With Chronic Hepatitis B

The purpose of this study is to evaluate the safety and tolerability of JNJ-440 in healthy and Chronic Hepatitis B (CHB) participants after single and multiple doses; and to evaluate the pharmacokinetic (PK) of JNJ-440 in healthy participants and in CHB participants following single and multiple dose regimens, administered alone (healthy participants and CHB participants).


Eligibility Criteria:
Inclusion Criteria:

Inclusion Criteria for Healthy Participants:

* Female participants (except for postmenopausal women) must have a negative pregnancy test at screening and on Day -1
* Participants must have a body mass index (BMI; weight in kilogram \[kg\] divided by the square of height in meters) of 18.0 to 30.0 kilogram per meter square (kg/m\^2), extremes included
* Participants must agree not to donate blood during the study and for at least 1 month after the completion of study drug administration

Inclusion Criteria for Participants with Chronic Hepatitis B (CHB):

* Participant must have CHB infection documented by: (a) Serum hepatitis B surface antigen (HBsAg) positive at screening and at least 6 months prior to screening; (b) Serum antibody immunoglobulin M (IgM) anti-HBc antibody negative at screening
* Participants must currently not be receiving any CHB treatment at screening, that is, have never received treatment with hepatitis B virus (HBV) antiviral medicines, nucleos(t)ide analog (NAs), interferon (IFN) products, or investigational anti-HBV agents, OR Have not been on treatment with HBV antiviral medicines, NAs, or IFN products within 6 months prior to baseline (first intake of study drugs)

Exclusion Criteria:

Exclusion Criteria for Healthy Participants:

* Participants with a past history of cardiac arrhythmias (example, extrasystoli, tachycardia at rest), history of risk factors for Torsade de Pointes syndrome (example, hypokalemia, family history of long QT Syndrome) or history or other clinical evidence of significant or unstable cardiac disease (example, angina, congestive heart failure, myocardial infarction, diastolic dysfunction, significant arrhythmia, coronary heart disease, and/or clinically significant electrocardiogram \[ECG\] abnormalities), moderate to severe valvular disease or uncontrolled hypertension at screening. Any evidence of heart block or bundle branch block is also exclusionary
* Participants with any history of confirmed clinically significant skin disease such as, but not limited to, dermatitis, eczema, drug rash, psoriasis, food allergy, and urticarial
* Participants with a history of confirmed clinically significant drug allergy such as, but not limited to, sulfonamides and penicillins, or drug allergy witnessed in previous studies with experimental drugs

Exclusion Criteria for Participants with CHB:

* Participant with positivity of anti-HBs antibodies
* Participants with current hepatitis D virus (HDV) infection (confirmed by HDV antibody) at screening