Study To Evaluate Safety and Efficacy of Vesatolimod for the Treatment of Chronic Hepatitis B Virus in Virally-Suppressed Participants
Condition: Chronic Hepatitis B
MeSH terms: Hepatitis A; Hepatitis B; Hepatitis B, Chronic; Hepatitis; Hepatitis, Chronic
Intervention: Vesatolimod; Placebo
Intervention description: Vesatolimod tablet administered orally; Placebo to match vesatolimod tablet administered orally
Intervention MeSH terms: Vesatolimod
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Sequential Assignment
Masking: Double (Participant, Care Provider)
Enrollment: 162.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: No
Keywords: Hepatitis B; HBV; GS-9620; TLR-7 Agonist

Summary:

      The primary objectives of this study are to evaluate the safety, tolerability, and efficacy
      of vesatolimod in participants with chronic hepatitis B (CHB) infection currently being
      treated with oral antivirals (OAV).

      Participants will be randomized in 3 sequential cohorts (Cohorts A, B, and C). Within each
      cohort, participants will be randomized in a 1:3:3:3 ratio to placebo or one of the doses of
      vesatolimod (1, 2, or 4 mg).
    

Eligibility criteria:

        Key Inclusion Criteria:

          -  Must have the ability to understand and sign a written informed consent form; consent
             must be obtained prior to initiation of study procedures

          -  Documented evidence of CHB infection (eg, hepatitis B surface antigen [HBsAg] positive
             for more than 6 months) with detectable HBsAg levels at screening

          -  Have been on approved HBV OAV treatment for ≥ 1 year prior to screening, with HBV DNA
             below lower limit of quantitation (LLOQ), measured at least once, 6 or more months
             prior to screening, and HBV DNA < 20 IU/mL at screening

          -  Currently taking an approved HBV OAV (tenofovir, entecavir, adefovir, lamivudine, or
             telbivudine, either as single agents or in combination) with no change in regimen for
             3 months prior to screening

          -  Willing to provide blood sample for toll-like receptor 7 (TLR-7) and interleukin 28 B
             (IL28B) single-nucleotide polymorphism (SNP) assessment

          -  Must be willing and able to comply with all study requirements

        Key Exclusion Criteria:

          -  Extensive bridging fibrosis or cirrhosis

          -  Laboratory parameters not within defined thresholds for neutropenia, anemia,
             thrombocytopenia, leukopenia, or other evidence of inadequate liver function

          -  Coinfection with hepatitis C virus (HCV), HIV, or hepatitis D virus (HDV)

          -  Evidence of hepatocellular carcinoma

          -  Malignancy within 5 years prior to screening, with the exception of specific cancers
             that are cured by surgical resection (basal cell skin cancer, etc.). Participants
             under evaluation for possible malignancy are not eligible.

          -  Significant cardiovascular, pulmonary, or neurological disease

          -  Any of the following conditions that may worsen in response to interferon (IFN):

               -  Autoimmune disease (eg, lupus erythematosus, rheumatoid arthritis, inflammatory
                  bowel disease, sarcoidosis, moderate or severe psoriasis)

               -  Poorly controlled diabetes mellitus

               -  Significant psychiatric disorders

               -  Thyroid disorder (unless controlled under treatment)

               -  Significant pulmonary diseases (eg, chronic obstructive pulmonary disease)

               -  Retinal disease

               -  Immunodeficiency disorders

          -  Received solid organ or bone marrow transplant

          -  Received prolonged therapy with immunomodulators (eg, corticosteroids) or biologics
             (eg, monoclonal Ab, interferon) within 3 months of screening

          -  Use of another investigational agents within 3 months of screening

          -  Current alcohol or substance abuse judged by the investigator to potentially interfere
             with compliance

          -  Females who are pregnant or may wish to become pregnant during the study

        Note: Other protocol defined Inclusion/Exclusion criteria may apply.