ACT201 Injection in Healthy Participants and Participants With Chronic Hepatitis B (CHB)

A Single-Center, Randomized, Double-Blind, Placebo-Controlled, Dose-Escalation Phase I Clinical Trial to Evaluate the Safety, Tolerability, Pharmacokinetics, Preliminary Efficacy, Drug Concentration-QTc Relationship, and Immunogenicity Profiles of Single and Multiple Doses of ACT201 Injection in Healthy Participants and Participants With Chronic Hepatitis B

This is a single-center, randomized, double-blind, placebo-controlled Phase I clinical trial consisting of two parts. Part 1 includes single ascending dose (SAD) and multiple ascending dose (MAD) cohorts conducted in healthy participants. Part 2 is a multiple ascending dose (MAD) trial enrolling HBeAg-negative chronic hepatitis B (CHB) participants with suppressed HBV DNA under stable nucleos(t)ide analog (NA) therapy.

Study Overview

• Status: Recruiting
• Conditions: Chronic Hepaititis B
• Intervention / Treatment: Drug: ACT201 Injection; Drug: ACT201 Injection Placebo

• Study Type: Interventional
• Enrollment (Estimated): 72
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Jing Zhang, Ph.D.; Phone Number: 021-52887926; Email: Zhangj_fudan@163.com
• Study Contact Backup: Name: Wenhong Zhang, Ph.D.; Phone Number: 18121186602; Email: zhangwenhong@fudan.edu.cn

Study Locations

• China
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China
      • Recruiting
      • Huashan Hospital, Fudan University
      • Contact: Jing Zhang, Ph.D.; Phone Number: 021-52887926; Email: Zhangj_fudan@163.com
      • Contact: Wenhong Zhang, Ph.D.; Phone Number: 18121186602; Email: zhangwenhong@fudan.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Part 1:

• Participants fully understand the purpose, nature and methods of the trial as well as potential adverse events, voluntarily participate in this trial and provide written informed consent;
• Aged between 18 and 55 years old (inclusive) at the time of informed consent, male or female;
• Body mass index meets specified criteria;
• Physical examination, vital signs, laboratory tests, electrocardiogram and imaging examinations at screening are normal or abnormalities are considered clinically insignificant;
• Participants (including their partners) are willing to use effective contraceptive measures from screening through 6 months after the last administration of investigational product, with no plans for pregnancy, sperm donation or oocyte donation.

Part 2:

• Participants fully understand the purpose, nature and methods of the trial as well as potential adverse events, voluntarily participate in this trial and provide written informed consent;
• Aged between 18 and 65 years old (inclusive) at the time of informed consent, male or female;
• Body mass index meets specified criteria;
• HBsAg-positive or HBV DNA-positive for at least 6 months, or previous liver biopsy confirming chronic HBV infection;
• Receiving stable nucleos(t)ide analogue (NA) therapy at screening, with no planned changes to NA regimen during the trial;
• Serum ALT ≤ 2 × ULN at screening; HBeAg, HBV DNA and HBsAg levels meet protocol-specified criteria;
• Participants (including their partners) are willing to use effective contraceptive measures from screening through 6 months after the last administration of investigational product, with no plans for pregnancy, sperm donation or oocyte donation.

Exclusion Criteria:

Part 1:

• Known or suspected hypersensitivity to ACT201 or its excipients; or participants with allergic diathesis (multiple drug and food allergies judged clinically significant by the Investigator).
• History of clinically significant diseases involving cardiovascular, hematologic and lymphatic, urinary, endocrine, immune, psychiatric, or nervous systems (e.g., epilepsy).
• Vital signs or laboratory examinations at screening meet the exclusion cut-off values specified in the protocol.
• Use of any prescription drugs, over-the-counter medications, vitamin products or herbal medicines within 2 weeks prior to the first dose (topical medications with local effects are excluded).
• Positive HBsAg, hepatitis B core antibody, hepatitis C antibody, human immunodeficiency virus antibody, or Treponema pallidum antibody at screening.
• QTcF interval (QT corrected by Fridericia's formula) > 450 ms at screening.
• Daily cigarette consumption exceeding 5 cigarettes within 3 months before screening.
• History of drug abuse or illicit drug use within 1 year before screening, or positive urine drug screen at screening.
• History of alcohol abuse within 6 months before screening (14 alcohol units per week: 1 unit = 285 mL beer with ~3.5% alcohol, or 25 mL spirits with ~40% alcohol, or 100 mL wine with ~10% alcohol), or positive breath alcohol test at screening.
• Vaccination administered within 1 month before screening, or planned vaccination during the trial period.
• Blood loss or blood donation ≥ 400 mL within 3 months before screening (menstrual bleeding in female participants excluded), or planned blood donation during the trial period.
• Female participants who are breastfeeding or have a positive serum pregnancy test at screening.
• Participation in any clinical trial with an investigational medicinal product/investigational device within 3 months before screening or within 5 half-lives (whichever is longer).
• Any other condition deemed unsuitable for trial participation by the Investigator.

Part 2：

• Major trauma or major surgery within 3 months before screening; or planned surgery during the trial period that may impair trial compliance or safety assessment as assessed by the Investigator.
• Uncontrolled and clinically significant abnormalities other than chronic HBV infection, such as acute cerebrovascular disease, severe or unstable cardiac disease, uncontrolled diabetes, uncontrolled hypertension, uncontrolled dyslipidemia, etc.
• History of other clinically significant liver diseases.
• History of liver cirrhosis or progressive liver fibrosis; or liver stiffness measurement (LSM) ≥ 8.5 kPa at screening.
• Alpha-fetoprotein > 50 ng/mL, or imaging suggestive of possible malignant hepatic lesions.
• Past or current manifestations of hepatic decompensation.
• History of extrahepatic diseases potentially related to HBV immune status.
• History of vasculitis; or signs/symptoms suggestive of underlying vasculitis; or past/current other diseases potentially associated with vasculitic disorders.
• Active infection requiring systemic antiviral or antibacterial treatment at screening, excluding HBV infection.
• History of malignant tumors within 5 years before screening, except for specific curable cancers resected surgically.
• Prior solid organ or bone marrow transplantation.
• Use of systemic immunosuppressants within 3 months before the first dose of investigational product [short-term (≤7 days) glucocorticoids for prophylaxis or treatment of non-autoimmune diseases excluded]; use of immunomodulators or cytotoxic agents within 6 months before the first dose of investigational product.
• Receipt of any oligonucleotide or small interfering RNA (siRNA) therapy within 12 months before the first dose of investigational product.
• Coexisting indication for anticoagulant therapy or anticipated requirement for anticoagulation during the trial.
• Any of the following laboratory results at screening, or other clinically significant abnormalities rendering the participant unsuitable for trial participation:

Platelet count < 125 × 10^9/L Absolute neutrophil count < 1.5 × 10^9/L Hemoglobin < 100 g/L Total bilirubin > 1.25 × ULN Serum albumin < 35 g/L Estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m^2 (calculated using the CKD-EPI formula) Prothrombin time international normalized ratio (INR) > 1.25 Positive hepatitis C antibody, human immunodeficiency virus antibody, or Treponema pallidum antibody

• QTcF interval (QT corrected by Fridericia's formula) > 450 ms at screening, or other clinically significant electrocardiogram abnormalities identified at screening.
• Known or suspected hypersensitivity to ACT201 or its excipients; or participants with allergic diathesis (multiple drug and food allergies judged clinically significant by the Investigator).
• Daily cigarette consumption exceeding 5 cigarettes within 3 months before screening.
• History of drug abuse or illicit drug use within 1 year before screening, or positive urine drug screen at screening.
• History of alcohol abuse within 6 months before screening, or positive breath alcohol test at screening.
• Vaccination administered within 1 month before screening, or planned vaccination during the trial period.
• Blood loss or blood donation ≥ 400 mL within 3 months before screening (menstrual bleeding in female participants excluded), or planned blood donation during the trial period.
• Female participants who are breastfeeding or have a positive serum pregnancy test at screening.
• Participation in any clinical trial with an investigational medicinal product/investigational device within 3 months before screening or within 5 half-lives (whichever is longer).
• Any other condition deemed unsuitable for trial participation by the Investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ACT201 Injection group	Drug: ACT201 Injection; Part 1 SAD (Single Ascending Dose): Single-dose subcutaneous injection per assigned dose group. Part 1 MAD (Multiple Ascending Dose) and Part 2: Subcutaneous injection per assigned dose group; treatment duration shall follow the study protocol.
Placebo Comparator: ACT201 Injection Placebo	Drug: ACT201 Injection Placebo; Part 1 SAD (Single Ascending Dose): Single-dose subcutaneous injection administered per assigned dose group. Part 1 MAD (Multiple Ascending Dose) and Part 2: Subcutaneous injection administered per assigned dose group; the treatment duration shall comply with the study protocol.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety: number of participants with adverse event (AE), serious adverse events (SAE) and clinically significant examination results.	Assessments include vital signs, physical examinations, laboratory tests, and 12-lead electrocardiograms (ECGs).	throughout the full study period,an average of 4 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Plasma drug concentrations in healthy participants and participants withCHB	throughout the full study period,an average of 4 months
Area Under the Concentration-Time Curve from time zero to the last measurable concentration（AUC₀-ₜ）	throughout the full study period,an average of 4 months
Area Under the Concentration-Time Curve from time zero to infinity（AUC₀-∞）	throughout the full study period,an average of 4 months
Apparent Volume of Distribution（Vd/F）	throughout the full study period,an average of 4 months
First-order Elimination Rate Constant(Kel)	throughout the full study period,an average of 4 months
Elimination Half-life(t₁/₂)	throughout the full study period,an average of 4 months
Mean Residence Time(MRT)	throughout the full study period,an average of 4 months
Apparent Clearance(CL/F)	throughout the full study period,an average of 4 months
Minimum Plasma Concentration at Steady State(Cₘᵢₙ,ₛₛ)	throughout the full study period,an average of 4 months
Maximum Plasma Concentration at Steady State(Cₘₐₓ,ₛₛ)	throughout the full study period,an average of 4 months
Average Plasma Concentration at Steady State(Cₐᵥ,ₛₛ)	throughout the full study period,an average of 4 months
Area Under the Concentration-Time Curve over one dosing interval at steady state(AUC₀-τ)	throughout the full study period,an average of 4 months
Degree of Fluctuation (DF)	throughout the full study period,an average of 4 months
Accumulation Factor (Rac)	throughout the full study period,an average of 4 months
Urinary Concentration	throughout the full study period,an average of 4 months
Cumulative Amount Excreted in Urine	throughout the full study period,an average of 4 months
Cumulative Percentage of Dose Excreted in Urine	throughout the full study period,an average of 4 months
Renal Clearance(CL)	throughout the full study period,an average of 4 months
HBsAg and HBsAb levels and changes from baseline among participants with CHB	throughout the full study period,an average of 4 months
HBsAg seroclearance rate among participants with CHB	throughout the full study period,an average of 4 months
HBsAg seroconversion rate among participants with CHB	throughout the full study period,an average of 4 months
Placebo-corrected baseline-adjusted ΔQTc (ΔΔQTc) among healthy participants	throughout the full study period,an average of 4 months
Anti-drug antibody (ADA) positive rate among healthy participants and participants with CHB	throughout the full study period,an average of 4 months
Antibody titers among healthy participants and participants with CHB	throughout the full study period,an average of 4 months

Collaborators and Investigators

• Sponsor: Xiamen Amoytop Biotech Co., Ltd.
• Collaborators: Huashan Hospital
• Investigators: Principal Investigator: Jing Zhang, Ph.D., Huashan Hospital; Principal Investigator: Wenhong Zhang, Ph.D., Huashan Hospital

Study record dates

Study Major Dates

• Study Start (Actual): August 6, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): April 1, 2027

Study Registration Dates

• First Submitted: July 20, 2026
• First Submitted That Met QC Criteria: July 29, 2026
• First Posted (Actual): August 3, 2026

Study Record Updates

• Last Update Posted (Actual): August 17, 2026
• Last Update Submitted That Met QC Criteria: August 14, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Chronic Hepaititis B; ACT201 Injection
• Other Study ID Numbers: ACT201-4-1-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No