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

Gilead Sciences

Status and phase: Enrolling; Phase 2; Phase 1

Conditions: Chronic Hepatitis Delta

Treatments: Drug: GS-4321 Placebo; Drug: GS-4321

Study type: Interventional

Funder types: Industry

Identifiers

NCT07096193

2025-522729-36 (Other Identifier)

GS-US-567-6968

Details and patient eligibility

About

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 is 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.

Enrollment: 107 estimated patients

Sex: All

Ages: 18 to 70 years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Key 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 entecavir, TAF, or TDF for the treatment of hepatitis B virus (HBV) infection at or prior to enrollment. Coformulation as part of a fixed-dose combination for the treatment of HIV is permitted.
• Non-cirrhotic or compensated cirrhosis.
• 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.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Sequential Assignment

Masking: Double Blind

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107 participants in 3 patient groups, including a placebo group

Phase 1: GS-4321

Experimental group

Description:

Participants will receive single escalating doses of GS-4321.

Treatment:

Drug: GS-4321

Drug: GS-4321

Phase 1: Placebo

Placebo Comparator group

Description:

Participants will receive placebo to match the single escalating doses of GS-4321

Treatment:

Drug: GS-4321 Placebo

Phase 2: GS-4321

Experimental group

Description:

Participants will receive multiple escalating doses of GS-4321 up to 96 weeks.

Treatment:

Drug: GS-4321

Drug: GS-4321