A Study to Evaluate the Safety of BG-A3004 in Healthy Participants and Patients With Immune-Mediated Skin Diseases

A Phase 1, Randomized, Double-Blind, Placebo Controlled, First-in-Human Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Pharmacodynamics of BG-A3004 in Healthy Participants and Patients With Immune-Mediated Skin Diseases

This is the first-in-human study of BG-A3004. The study will evaluate the safety, tolerability, pharmacokinetics (PK), immunogenicity, and pharmacodynamics (PD) of BG-A3004 after single and multiple doses administered in different dose levels in healthy participants (Part A) and patients with immune-mediated skin diseases (Part B), respectively.

Study details include:

• The study duration will be approximately 3 years.
• The treatment duration will be 1 dose for Part A and 4 doses for Part B.
• Safety follow-up period is 168 days after the last dose

Study Overview

• Status: Recruiting
• Conditions: Skin Diseases
• Intervention / Treatment: Biological: BG-A3004; Biological: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 98
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Study Director; Phone Number: +1-877-828-5568; Email: clinicaltrials@beonemed.com

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100034
      • Recruiting
      • Peking University First Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria

• Evidence of a personally signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study.
• Female participants of childbearing potential must be willing to use a highly effective method of birth control and refrain from egg donation for the duration of the study and for 180 days after the last dose of study drug. They must also have a negative urine pregnancy test at baseline before first dose of study drug.
• Nonsterile male participants must be willing to use a highly effective method of birth control and refrain from sperm donation for the duration of the study and for 180 days after the last dose of study drug.

Part A (SAD) specific Inclusion criteria

• Healthy participants as determined by medical evaluation, including medical history, physical examination, laboratory tests, and cardiac monitoring.
• must be 18 to 55 years of age, inclusive, at the time of signing the informed consent.
• Body mass index (BMI) of 19 to 28 kg/m^2

Part B (MAD) specific inclusion criteria:

• Must be 18 to 60 years of age, inclusive, at the time of signing the informed consent.
• Body mass index (BMI) of 18 to 32 kg/m^2
• Patients with alopecia areata (AA), clinical diagnosis of AA with no other etiology of hair loss. Severity of Alopecia Tool (SALT) ≥ 25 and < 95 at screening and randomization.
• Patients with cutaneous lichen planus (CLP), clinical and histological features of LP with predominant cutaneous involvement. Investigator's Global Assessment (IGA) score of 3 or 4 at screening and randomization.
• Patients with nonsegmental vitiligo (NSV), documented clinical diagnosis of NSV for at least 3 months. Facial-Vitiligo Area Scoring Index (F-VASI) ≥ 0.5 and Total body-VASI ≥ 3 at screening and randomization.

Exclusion Criteria:

• Participants who have a history of severe allergic reactions or hypersensitivity to the active ingredient and excipients of the study drug or drugs of the same class.
• Participants who are unable to comply with the requirements of the protocol, unless the written approval of the medical monitor has been obtained before informed consent.
• Participants with any malignancy ≤ 5 years before randomization, except for any locally recurring cancer that has been treated curatively
• Participants who were administered a live vaccine ≤ 28 days before randomization.
• Female participants who are pregnant or are breastfeeding.
• History of Tuberculosis or active, latent, or inadequately treated infection
• A known history of a primary immunodeficiency or an underlying condition such as HIV infection or splenectomy that predispose the participant to infections.
• Known infection with hepatitis B virus [presence of hepatitis B surface antigen (HBsAg) or hepatitis B core antibody( HBcAb)], or presence of hepatitis C virus antibody (HCV Ab)
• Have a history of any lymphoproliferative disorder (such as Epstein Barr Virus-related lymphoproliferative disorder, as reported in some participants on other immunosuppressive drugs), history of lymphoma, leukemia, myeloproliferative disorders, multiple myeloma, or signs and symptoms suggestive of current lymphatic disease.
• Have an active infection or a history of infection within 6 months before the first dose of study drug that required hospitalization, or parenteral antimicrobial therapy, or have a history of opportunistic infection or a chronic or recurrent infectious disease that, in the opinion of the investigator, makes them unsuitable for this study.
• Have or have had symptomatic herpes zoster or herpes simplex within 12 weeks, more than 1 episode of local herpes zoster, or a history (single episode) of disseminated zoster.
• Acute disease state (e.g., asthma attack, nausea, vomiting, fever, or diarrhea) within 7 days prior to the first dose of study drug.

Part B(MAD) specific exclusion criteria:

• Previous use of any Janus Kinase (JAK) inhibitor for any disease indication at any time.
• Treatment with systemic immunomodulatory medications within 4 weeks or 5 half-lives (if known), whichever is longer prior to randomization, including immunosuppressants (e.g., methotrexate, cyclosporine, azathioprine); corticosteroids administered orally, intravenously, or intramuscularly; chloroquine derivatives; and oral phosphodiesterase-4 (PDE4) inhibitors (e.g., apremilast).
• Phototherapy (UV or laser therapy) or cryotherapy within 4 weeks prior to randomization.
• For AA patients, AA that affects more than scalp hair, e.g., eyebrow, eyelash, body hair.
• For CLP patients, Patients whose LP is a predominantly bullous variant.
• For NSV patients, Participants who have no pigmented hair within any of the vitiligo areas on the face.

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

Study Plan

How is the study designed?

Design Details

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

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A: Single Ascending Doses (SAD) of BG-A3004; Sequential cohorts of increasing dose levels of BG-A3004 will be evaluated after a single dose in healthy participants.	Biological: BG-A3004; Administered subcutaneously
Experimental: Part B: Multiple Ascending Doses (MAD) of BG-A3004; Sequential cohorts of increasing dose levels of BG-A3004 will be evaluated after multiple doses in participants with immune-mediated skin diseases.	Biological: BG-A3004; Administered subcutaneously
Placebo Comparator: SAD Placebo; Sequential cohorts of healthy participants will receive a single dose of matching placebo.	Biological: Placebo; Administered subcutaneously
Placebo Comparator: MAD Placebo; Sequential cohorts of participants with immune-mediated skin diseases will receive multiple doses of matching placebo.	Biological: Placebo; Administered subcutaneously

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part A (SAD) and Part B (MAD): Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs)	Number of participants with treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs), including clinically significant abnormalities from laboratory tests, vital signs and electrocardiogram results	up to 24 weeks for Part A and 36 weeks for Part B

Secondary Outcome Measures

Outcome Measure	Time Frame
Part A (SAD) and Part B (MAD): Maximum observed serum concentration of BG-3004 (Cmax)	up to 24 weeks for Part A and 36 weeks for Part B
Part A (SAD) and Part B (MAD): Area under the curve (AUC) of BG-3004	up to 24 weeks for Part A and 36 weeks for Part B
Part A (SAD) and Part B (MAD): Half-life of BG-3004 (t1/2)	up to 24 weeks for Part A and 36 weeks for Part B
Part A (SAD) and Part B (MAD): Number of Participants with Antidrug Antibodies (ADAs) against BG-A3004	up to 24 weeks for Part A and 36 weeks for Part B
Part B (MAD): Trough concentration (Ctrough) of BG-3004	up to 36 weeks

Collaborators and Investigators

• Sponsor: BeOne Medicines
• Investigators: Study Director: Study Director, BeOne Medicine

Study record dates

Study Major Dates

• Study Start (Actual): March 19, 2026
• Primary Completion (Estimated): August 8, 2028
• Study Completion (Estimated): August 8, 2028

Study Registration Dates

• First Submitted: February 9, 2026
• First Submitted That Met QC Criteria: February 9, 2026
• First Posted (Actual): February 17, 2026

Study Record Updates

• Last Update Posted (Actual): March 23, 2026
• Last Update Submitted That Met QC Criteria: March 20, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Skin and Connective Tissue Diseases; Skin Diseases
• Other Study ID Numbers: BG-A3004-101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

IPD Plan Description

BeOne shares data on completed studies responsibly and provides qualified scientific and medical researchers access to data and supporting documentation for clinical trials in dossiers for medicines and indications after submission and approval in the United States, China, and Europe. Clinical trials supporting subsequent local approvals, new indications, or combination products are eligible for sharing once corresponding regulatory approvals are achieved.

BeOne shares data only when permitted by applicable data privacy and security laws and regulations, when it is feasible to do so without compromising the privacy of study participants, and other considerations.

Qualified researchers with appropriate competencies who are engaged in novel scientific research may submit a request for participant-level data with a research proposal for BeOne review. Research teams must include a biostatistician and sign a Data Sharing Agreement prior to receiving access to clinical trial data.

• IPD Sharing Time Frame: See plan description
• IPD Sharing Access Criteria: See plan description
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; CSR

Drug and device information, study documents

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