A Study to Assess the Safety, Tolerability, and Pharmacokinetics of GIGA-2339 in Participants With Chronic Hepatitis B Virus Infection

Phase 1

Recruiting

• Conditions: Hepatitis B Virus Infection
• Interventions: Drug: GIGA-2339; Drug: Placebo

• Registration Number: NCT07024641
• Lead Sponsor: GigaGen, Inc.

Brief Summary

The primary purpose of this study is to assess the safety and tolerability of single and multiple intravenous (IV) doses of GIGA-2339 in participants with chronic Hepatitis B Virus (HBV) infection.

Detailed Description

Not available

Study Timeline

• Study Start: 2024-11-13
• Study First Submitted: 2025-04-30
• Study First Submitted QC: 2025-06-09
• Study First Posted: 2025-06-17
• Status Verified: 2025-08
• Last Update Submitted: 2025-08-14
• Last Update Posted: 2025-08-19
• Primary Completion: 2027-09
• Study Completion: 2027-09-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 48

Inclusion Criteria

• Hepatitis B envelope antigen (HBeAg) negative chronic HBV infection for ≥ 6 months, defined as presence of Hepatitis B surface antigen (HBsAg) in serum for ≥ 6 months.
• Serum HBsAg concentration between ≥ 100 international units per milliliter (IU/mL) and 2000 IU/mL at screening.
• Currently on stable dose of nucleot(s)ide analogues (NAs) (≥ 6 months) and expected to continue while in study.
• Serum HBV deoxyribonucleic acid (DNA) concentration ≤ 50 IU/mL at screening.
• Male participants must refrain from donating spermatozoa and agree to use highly effective contraception.
• Female participants must not be pregnant, or breastfeeding; either should not be a woman of childbearing potential (WOCBP) or if WOCBP should use highly effective contraceptive methods.

Key

Exclusion Criteria

• Positive for co-infection with hepatitis C virus (HCV), human immunodeficiency virus (HIV), hepatitis D virus (HDV) at screening.
• Participants that weigh less than 50 kilograms (kg) and/or have a body mass index (BMI) less than 18.5.
• History of documented liver cirrhosis at screening. Patients under liver cirrhosis evaluation at screening will not be eligible until cirrhosis is ruled out.
• Liver stiffness > 8 kilopascal (kPa) at screening.
• History of chronic liver disease from another cause, immune complex disease, or autoimmune diseases that in the opinion of the investigator would preclude participation.
• Family history of hepatocellular carcinoma (HCC).
• Alpha fetoprotein > 20 nanograms per milliliter (ng/mL).
• Presence of a liver imaging reporting and data system (LI-RADS) 4 or 5 liver lesion on imaging 12 months prior to Screening OR, LI-RADS-US findings of US-3 grade on imaging 12 months prior to Screening, OR LIRADS-US grade 3 done prior to the D1 infusion visit, if prior LI-RADS or LI-RADS-US results are not available at Screening.
• History of hematopoietic stem cell transplant or solid organ transplant.
• Receipt of anti-HBV monoclonal antibody (mAb) therapy of any kind in the past (including hepatitis B immunoglobulin [HBIG]).
• History of cardiovascular disease (e.g., coronary artery disease, cardiomyopathy, congestive heart failure, family history of congenital long QT syndrome).
• Malignancy diagnosed and/or treated within 5 years prior to Screening, and/or with ongoing treatment for malignancy, with the exception of localized non-metastatic basal cell or squamous cell carcinoma of the skin or in-situ carcinoma of the cervix excised with curative intent.
• Participants requiring anti-coagulation therapies (for example warfarin, Factor Xa inhibitors, or anti-platelet agents like clopidogrel).
• Male participants with a corrected QT interval using Fridericia's formula (QTcF) > 450 milliseconds (msec) and female participants with QTcF > 470 msec on ECG recorded at screening. Participants with evidence of intraventricular conduction delay, defined as QRS interval greater than 110 msec, will be excluded if the QTcF is > 500 msec for both males and females.
• Known hypersensitivity to any GIGA-2339 excipients or any confirmed significant allergic reactions (urticaria or anaphylaxis) against any drug, or multiple drug allergies (nonactive hay fever is acceptable), or a history of drug or other allergy that, in the opinion of the Investigator, contraindicates participation.
• Received or will receive live-attenuated virus vaccinations such as measles, mumps, rubella or varicella within 4 weeks before and up to three months after administration of investigational product (IP).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SEQUENTIAL

Arm && Interventions

Group	Intervention	Description
Part 1: Single Ascending Dose (SAD)	GIGA-2339	Participants will receive a single IV infusion of either GIGA-2339 or placebo in ascending doses on Day 1.
Part 1: Single Ascending Dose (SAD)	Placebo	Participants will receive a single IV infusion of either GIGA-2339 or placebo in ascending doses on Day 1.
Part 2: Multiple Ascending Dose (MAD)	GIGA-2339	Participants will receive multiple IV infusions of either GIGA-2339 or placebo, once every 4 weeks, at a dose determined in Part 1.
Part 2: Multiple Ascending Dose (MAD)	Placebo	Participants will receive multiple IV infusions of either GIGA-2339 or placebo, once every 4 weeks, at a dose determined in Part 1.

Primary Outcome Measures

Name	Time	Method
SAD and MAD: Number of Participants With Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)	SAD: Up to Day 105; MAD: Up to Day 245

Secondary Outcome Measures

Name	Time	Method
MAD: AUC Versus Time Curve During the Dosing Interval (AUC0-tau) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 245
MAD: Accumulation Ratio Cmax (ARCmax) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 245
MAD: Accumulation Ratio AUC (ARAUCs) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 245
SAD and MAD: Maximum Serum Concentration (Cmax) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
SAD and MAD: Area Under the Concentration Time Curve (AUC) from 0 to the Last Quantifiable Concentration (AUC0-t) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
SAD: AUC From 0 to Infinity (AUC0-∞) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 105
SAD: Dose Normalized Maximum Serum Concentration (DN_Cmax). of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 105
SAD: Dose Normalized AUC From 0 to the Last Quantifiable Concentration (DN_AUC0-t) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 105
SAD: Dose Normalized AUC From 0 to Infinity (DN_AUC0-∞) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 105
SAD and MAD: Time to Obtain Maximum Concentration (Tmax) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
SAD and MAD: Terminal Half-Life (t1/2) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
SAD and MAD: Volume of Distribution (Vz) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
SAD and MAD: Systemic Clearance (CL) of GIGA-2339	SAD: Pre-dose and at multiple timepoints post-dose up to Day 105; MAD: Pre-dose and at multiple timepoints post-dose up to Day 245
MAD: Serum Concentration at the End of the Dosing Interval (Ctrough) of GIGA-2339	Pre-dose and at multiple timepoints post-dose up to Day 245

Trial Locations

Locations (2)

Grifols Investigative site; 🇺🇸 Richmond, Virginia, United States

Grifols Investigative Site; 🇺🇸 Lenexa, Kansas, United States