A Study of JNJ 73763989+JNJ 56136379+Nucleos(t)Ide Analog (NA) Regimen Compared to NA Alone in e Antigen Negative Virologically Suppressed Participants With Chronic Hepatitis B Virus Infection

A Randomized, Double Blind, Placebo-controlled Phase 2b Study to Evaluate Efficacy, Pharmacokinetics, and Safety of 48-week Study Intervention With JNJ 73763989+JNJ 56136379+Nucleos(t)Ide Analog (NA) Regimen Compared to NA Alone in e Antigen Negative Virologically Suppressed Participants With Chronic Hepatitis B Virus Infection

The purpose of this study is to evaluate the efficacy of 48-week study intervention with JNJ-73763989+JNJ-56136379+nucleos(t)ide analog (NA) regimen compared to NA alone assessed by HBsAg levels. This study is part of HepB Wings Platform Trial (PLATFORMPAHPB2001).

Hepatitis B virus (HBV) is a small deoxyribonucleic acid (DNA) virus that infects the liver and can cause either acute or chronic infection. It consists of a so-called nucleocapsid in which viral DNA is packed with hepatitis B core protein (HBc) and membranous envelope containing hepatitis B surface antigen (HBsAg). Chronic HBV infection may lead to serious illnesses like cirrhosis and hepatocellular carcinoma (HCC). Oral treatment with NAs is effective at suppressing viral DNA formation and lowering virus concentration in blood to levels below lower limit of quantification (LLOQ). JNJ-73763989 is a liver-targeted antiviral therapeutic for subcutaneous injection designed to treat chronic HBV infection via ribonucleic acid interference mechanism but rarely lead to functional cure defined as sustained loss of HBs Ag and HBV DNA in serum. JNJ-56136379 is an orally administered capsid assembly modulator that is being developed for treatment of chronic HBV infection. The aim of study is to evaluate efficacy of 48-week study intervention with JNJ-3989+JNJ-6379+NA regimen compared to NA alone, assessed by HBsAg seroclearance at Week 72 (i.e., 24 weeks after completion of all study interventions at Week 48) without restarting NA treatment in HBeAg negative virologically suppressed chronic hepatitis B (CHB) infected participants who received NA treatment for at least 2 years prior to screening. The study will be 2.3 years and will be conducted in 3 phases: a screening phase (4 weeks), a study intervention phase (48 weeks), and a follow-up phase (48 weeks). Safety will be evaluated by AEs including AEs of special interest to any of the study interventions, clinical laboratory tests, ECGs, vital signs, and physical examinations.

Inclusion Criteria:

• Medically stable based on physical examination, medical history, vital signs, electrocardiogram (ECG) at screening
• Chronic hepatitis B virus (HBV) infection with documentation at least 6 months prior to screening
• Hepatitis B e (antigen) (HBeAg)-negative on stable nucleotide analogue (NA) treatment for at least 24 months prior to screening
• Hepatitis B surface antigen (HBsAg) greater than (>) 100 International Units per Milliliter (IU/mL) at screening
• Body mass index (BMI) between 18.0 and 35 kilogram per meter square (kg/m^2), extremes included
• Highly effective contraceptive measures in place for female participants of childbearing potential or male participants with female partners of childbearing potential
• Liver fibrosis stage 0-2 (Metavir) or Fibroscan less than (<) 9 Kilopascal (kPa) at screening

Exclusion Criteria:

• Evidence of infection with hepatitis A, C, D or E virus infection or evidence of human immunodeficiency, virus type 1 (HIV-1) or HIV-2 infection at screening
• History or evidence of clinical signs/symptoms of hepatic decompensation including but not limited to: portal hypertension, ascites, hepatic encephalopathy, esophageal varices or any laboratory abnormalities indicating a reduced liver function as defined in the protocol
• Evidence of liver disease of non-HBV etiology
• History or signs of cirrhosis or portal hypertension (nodules, no smooth liver contour, no normal portal vein, spleen size ≥12 cm) or signs of hepatocellular carcinoma (HCC)
• Significant laboratory abnormalities as defined in the protocol at screening
• Participants with a history of malignancy within 5 years before screening
• Abnormal sinus rhythm or ECG parameters at screening as defined in the protocol
• History of or current cardiac arrhythmia or history or clinical evidence of significant or unstable cardiac disease
• Participants with any current or previous illness for which, in the opinion of the investigator and/or sponsor, participation would not be in the best interest of the participant
• History of or current clinically significant skin disease or drug rash
• Known allergies, hypersensitivity, or intolerance to JNJ-73763989 and JNJ-56136379 or their excipients or to placebo content
• Contraindications to the use of entecavir (ETV), tenofovir disoproxil fumarate (TDF), or tenofovir alafenamide (TAF) per local prescribing information
• Participants who have taken any therapies disallowed per protocol