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Study of GS-4321 in Healthy Participants and Participants With Chronic Hepatitis Delta Virus

Not Applicable
Recruiting
Conditions
Chronic Hepatitis Delta
Interventions
Drug: GS-4321
Drug: GS-4321 Placebo
Registration Number
NCT07096193
Lead Sponsor
Gilead Sciences
Brief Summary

The goals of this clinical study are to first learn more about safety and dosing of the study drug GS-4321 in healthy participants. The study will then learn about the safety and effectiveness of GS-4321 in participants with chronic hepatitis delta (CHD).

The primary objective of Phase 1 of this study to evaluate the safety, tolerability and Pharmacokinetics (PK) of the escalating single doses of GS-4321 administered in healthy participants.

The primary objective of Phase 2 of this study is to evaluate the efficacy and safety of the multiple escalating doses of GS-4321 in participants with CHD.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
80
Inclusion Criteria

Part A:

  • Participants assigned male or female at birth who are of childbearing potential and engage in heterosexual intercourse must agree to use protocol-specified method(s) of contraception.
  • Have a body mass index (BMI) of ≤ 30.0 kg/m2 at screening and at admission.

Part B:

  • Participants assigned male or female at birth who are of childbearing potential and engage in heterosexual intercourse must agree to use protocol-specified method(s) of contraception.
  • Chronic hepatitis delta (CHD) for ≥ 6 months prior to screening, documented by prior medical history.
  • Must be receiving a commercially available nucleoside/nucleotide analogue for the treatment of hepatitis B virus (HBV) infection at enrollment.
  • Hepatitis delta virus ribonucleic acid (HDV RNA ) > 100 IU/mL at screening.
  • Alanine aminotransferase (ALT) level > 1 × Upper limit of normal (ULN), but < 10 × ULN at screening.

Key

Exclusion Criteria

Part A:

  • Positive serum or urine pregnancy test.
  • Participants with plans to breastfeed during the study period.

Part B:

  • Positive serum or urine pregnancy test.
  • Participants with plans to breastfeed during the study period.
  • Current or previous clinically decompensated liver disease, including coagulopathy, hepatic encephalopathy, and esophageal varices hemorrhage due to HDV or HBV.
  • Child-Turcotte-Pugh (CTP)-B or -C or a CTP score of ≥ 7.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SEQUENTIAL
Arm && Interventions
GroupInterventionDescription
Phase 1: GS-4321GS-4321Participants will receive single escalating doses of GS-4321.
Phase 1: PlaceboGS-4321 PlaceboParticipants will receive placebo to match the single escalating doses of GS-4321
Phase 2: GS-4321GS-4321Participants will receive multiple escalating doses of GS-4321 up to 96 weeks.
Primary Outcome Measures
NameTimeMethod
Phase 1 and 2: Percentage of Participants With Treatment-emergent Adverse EventsPhase 1: First dose up to 40 weeks; Phase 2: First dose up to 96 Weeks plus 48 weeks of posttreatment follow-up
Phase 1 and 2: Percentage of Participants With Treatment-emergent Serious Adverse EventsPhase 1: First dose up to 40 weeks; Phase 2: First dose up to 96 Weeks plus 48 weeks of posttreatment follow-up
Phase 1 and 2: Percentage of Participants Experiencing Treatment-emergent Clinical Laboratory AbnormalitiesPhase 1: First dose up to 40 weeks; Phase 2: First dose up to 96 Weeks plus 48 weeks of posttreatment follow-up
Phase 1: Serum Pharmacokinetic (PK) parameter; AUClast of GS-4321First dose up to 24 Weeks

AUClast is defined as the area under the concentration versus time curve from time zero to the last quantifiable concentration.

Phase 1: Serum PK Parameter: AUCinfFirst dose up to 24 Weeks

AUCinf is defined as the area under the concentration versus time curve extrapolated to infinite time.

Phase 1: Serum PK Parameter: CmaxFirst dose up to 24 Weeks

Cmax is defined as the maximum observed concentration of drug.

Phase 1: Serum PK Parameter: TmaxFirst dose up to 24 Weeks

Tmax is defined as the time (observed time point) of Cmax.

Phase 1: Serum PK Parameter: t1/2First dose up to 24 Weeks
Phase 2: Proportion of Participants with Combined ResponseUp to 96 Weeks

Combined Response is defined as undetectable hepatitis delta virus (HDV) RNA or ≥ 2 log10 decrease in HDV RNA from baseline and alanine aminotransferase (ALT) normalization (ALT \< upper limit of normal (ULN)).

Secondary Outcome Measures
NameTimeMethod
Phase 1: Proportion of Participants who Develop Antidrug Antibody (ADAs) After Administration of a Single Dose of GS-4321 and ADA Titer CharacterizationFirst dose up to 24 Weeks

ADA Titer characterization will include proportion of participants with ADA incidence, prevalence, persistence, and transience .

Phase 2: Serum PK Parameters AUCtau of GS-4321Up to 96 weeks
Phase 2: Serum PK Parameters Cmax of GS-4321Up to 96 Weeks
Phase 2: Serum PK Parameters Tmax of GS-4321Up to 96 Weeks
Phase 2: Serum PK Parameters Ctrough of GS-4321Up to 96 Weeks
Phase 2: Proportion of Participants With Undetectable HDV RNA or ≥ 2 log10 Decrease in HDV RNA From Baseline and ALT Normalization (ALT < ULN).Weeks 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, and 96
Phase 2: Change From Baseline in HDV RNA at Weeks 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, and 96Baseline, Weeks 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, and 96
Phase 2: Proportion of Participants With Undetectable HDV RNAWeeks 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, and 96
Phase 2: Change From Baseline in Liver Stiffness by Elastography at Weeks 24, 48, and 96Weeks 24, 48, and 96
Phase 2: Proportion of Participants with ALT NormalizationWeeks 4, 8, 12, 16, 20, 24, 36, 60, 72, 84, and 96
Phase 2: Proportion of Participants who Develop ADAs After Administration of Multiple Doses of GS-4321 and ADA Titer CharacterizationFirst dose up to 96 Weeks

ADA Titer characterization will include proportion of participants with ADA incidence, prevalence, persistence, and transience .

Phase 2: Characterize if Emergent Variants are Associated With Reduced Susceptibility to GS-4321 in Vitro and Virologic Failure in Participants With CHDFirst dose up to 96 Weeks

Trial Locations

Locations (1)

Investigative Site

🇺🇸

Anaheim, California, United States

Investigative Site
🇺🇸Anaheim, California, United States

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