Study of HBV Therapeutic Vaccines GS-2829 and GS-6779 in Healthy Participants and Participants... (2024)

Overview

The goal of this clinical study is to learn more about GS-2829 and GS-6779 in healthy participants and participants with CHB.

Full Title of Study: “A Phase 1a/1b Study to Evaluate the Safety and Tolerability of Repeated Doses of Nonreplicating Arenavirus Vector Therapeutic Vaccines GS-2829 and GS-6779 in Healthy Participants and Participants With Chronic Hepatitis B (CHB)”

Study Type

• Study Type: Interventional
• Study Design
  • Allocation: Randomized
  • Intervention Model: Parallel Assignment
  • Primary Purpose: Treatment
  • Masking: Double (Participant, Investigator)
• Study Primary Completion Date: January 2025

Interventions

• Biological: GS-2829
  • Administered intramuscularly
• Biological: GS-6779
  • Administered intramuscularly
• Biological: Placebo for GS-2829
  • Administered intramuscularly
• Biological: Placebo for GS-6779
  • Administered intramuscularly

Arms, Groups and Cohorts

• Experimental: Cohort 1: GS-2829 Dose A or Placebo
  • Healthy participants will receive GS-2829 Dose A or placebo for GS-2829.
• Experimental: Cohort 2: GS-6779 Dose B or Placebo
  • Healthy participants will receive GS-6779 Dose B or placebo for GS-6779.
• Experimental: Cohort 3: GS-2829 Dose A or Placebo + GS-6779 Dose B or Placebo
  • Healthy participants will receive GS-2829 Dose A or placebo for GS-2829 and GS-6779 Dose B or placebo for GS-6779.
• Experimental: Cohort 4: GS-2829 Dose C or Placebo + GS-6779 Dose D or Placebo
  • Healthy participants will receive GS-2829 Dose C or placebo for GS-2829 and GS-6779 Dose D or placebo for GS-6779.
• Experimental: Cohort 5: GS-2829 Dose A or Placebo + GS-6779 Dose B or Placebo
  • Participants with Chronic Hepatitis B (CHB) who are virally suppressed will receive GS-2829 Dose A or placebo for GS-2829 and GS-6779 Dose B or placebo for GS-6779.
• Experimental: Cohort 6: GS-2829 Dose C or Placebo + GS-6779 Dose D or Placebo
  • Participants with Chronic Hepatitis B (CHB) who are virally suppressed will receive GS-2829 Dose C or placebo for GS-2829 and GS-6779 Dose D or placebo for GS-6779.
• Experimental: Cohort 7: GS-2829 Dose C or Placebo + GS-6779 Dose D or Placebo
  • Participants with CHB who are virally suppressed will receive GS-2829 Dose C or placebo for GS-2829 and GS-6779 Dose D or placebo for GS-6779.
• Experimental: Cohort 8: GS-2829 Dose C or Placebo + GS-6779 Dose D or Placebo
  • Healthy participants will receive GS-2829 Dose C or placebo for GS-2829 and GS-6779 Dose D or placebo for GS-6779.

Clinical Trial Outcome Measures

Primary Measures

• Percentage of Participants With Treatment-emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)
  • Time Frame: First dose date to end of study followed up to 24 weeks post last dose (Up to Day 225 for Cohorts 1 and 2; Up to Day 309 for Cohorts 3-8)
• Percentage of Participants With Treatment-emergent Laboratory Abnormalities
  • Time Frame: First dose date to end of study followed up to 24 weeks post last dose (Up to Day 225 for Cohorts 1 and 2; Up to Day 309 for Cohorts 3-8)

Secondary Measures

• Proportion of Participants With Vaccine-induced Immune Response
  • Time Frame: First dose date to end of study followed up to 24 weeks post last dose (Up to Day 225 for Cohorts 1 and 2; Up to Day 309 for Cohorts 3-8)
• Magnitude of Vaccine-Induced Immune Responses as Measured by T-Cell Levels (T-Cell Responses to HBV)
  • Time Frame: First dose date to end of study followed up to 24 weeks post last dose (Up to Day 225 for Cohorts 1 and 2; Up to Day 309 for Cohorts 3-8)

Participating in This Clinical Trial

Key Inclusion Criteria:

Phase 1a and 1b:

• Body mass index (BMI) of ≤ 32.0 kg/m^2. – Non-diabetic without impaired glucose tolerance. – No evidence of cardiac disease based on 12 lead ECG. Phase 1a (Healthy Individuals) only: – Aged 18 through 60 years. – No history of Hepatitis B infection with a negative Hepatitis B virus (HBV) core Antibody. Phase 1b (Virally suppressed CHB individuals): – Aged 18 through 65 years. – Documented CHB and HBsAg ≤ 5000 IU/mL at screening. – No evidence of advanced fibrosis by Fibroscan (defined as Fibroscan < 9 kPa within 6 months of screening). – Diagnosed with chronic hepatitis B on suppressive oral antiviral for ≥ 6 months. Key Exclusion Criteria:

Phase 1a and 1b:

• Use of any systemic antibiotics within 30 days of screening. – Receipt of any HBV vaccine within 12 months of screening visit or planning HBV vaccination during the study period. – Receipt of any investigational product within 3 months or vaccine within 3 months of screening (with the exception of influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines, which if needed, should be administered at least 14 days before or after an investigational product administration). – Receipt of immunoglobulin or other blood products within 3 months of screening. – Positive serum pregnancy test at screening or positive urine pregnancy on Day 1. – Have been treated with systemic steroids, immunosuppressant therapies, or chemotherapeutic agents within 3 months prior to screening or is expected to receive these agents during the study (eg, corticosteroids, immunoglobulins, other immune or cytokine-based therapies). – Participation in any other clinical study (including observational studies) without prior approval from the sponsor is prohibited while participating in the study. Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 65 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

• Lead Sponsor
  • Gilead Sciences
• Provider of Information About this Clinical Study
  • Sponsor
• Overall Official(s)
  • Gilead Study Director, Study Director, Gilead Sciences