NCT07235384

Brief Summary

This is a phase 1/1b randomized, double blind, placebo-controlled, single dose escalation (SAD) and multiple dose escalation (MAD) study to evaluate the safety, tolerability, and pharmacokinetics (PK) of ZL-1503 in healthy volunteers and participants with moderate to severe atopic dermatitis (AD)

Trial Health

80
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
84

participants targeted

Target at P75+ for phase_1

Timeline
15mo left

Started Dec 2025

Typical duration for phase_1

Geographic Reach
3 countries

12 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress41%
Dec 2025Dec 2027

First Submitted

Initial submission to the registry

November 14, 2025

Completed
5 days until next milestone

First Posted

Study publicly available on registry

November 19, 2025

Completed
12 days until next milestone

Study Start

First participant enrolled

December 1, 2025

Completed
2.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 28, 2027

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 28, 2027

Last Updated

August 7, 2026

Status Verified

December 1, 2025

Enrollment Period

2.1 years

First QC Date

November 14, 2025

Last Update Submit

August 6, 2026

Conditions

Keywords

Atopic Dermatitis

Outcome Measures

Primary Outcomes (5)

  • Number of participants with adverse events (AEs)

    Up to 48 weeks after last intervention

  • Number of participants with serious adverse events (SAEs)

    Up to 48 weeks after last intervention

  • Number of participants with clinical laboratory abnormalities

    Up to 48 weeks after last intervention

  • Number of participants with vital sign abnormalities

    Up to 48 weeks after last intervention

  • Number of participants with electrocardiogram (ECG) abnormalities

    Up to 48 weeks after last intervention

Study Arms (2)

ZL-1503: Participants will receive single ascending doses of ZL-1503

EXPERIMENTAL

Part A: Single Ascending Dose (SAD)

Drug: ZL-1503Drug: Placebo

ZL-1503: Participants will receive multiple ascending doses of ZL-1503

EXPERIMENTAL

Part B: Multiple Ascending Dose (MAD)

Drug: ZL-1503Drug: Placebo

Interventions

Healthy volunteers will receive ZL-1503.

ZL-1503: Participants will receive single ascending doses of ZL-1503

Healthy volunteers will receive placebo.

ZL-1503: Participants will receive single ascending doses of ZL-1503

Eligibility Criteria

Age18 Years - 65 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Part A:
  • Healthy male and female volunteers, 18-65 years of age
  • Body mass index (BMI) between ≥ 18.5 and \< 32.5 kg/m2
  • Negative pregnancy tests for women of childbearing potential.
  • Part B:
  • years of age;
  • BMI between ≥18.5 and \<40.0 kg/m2
  • Have a diagnosis of AD at least 12 months prior to Day 1;
  • Moderate-to-severe AD at Screening and Baseline visit, defined as:
  • Eczema Area and Severity Index (EASI) score ≥ 16;
  • Affected Body Surface Area (BSA)≥ 10%;
  • vIGA-AD™ score ≥ 3
  • History of an inadequate response to treatment with topical medications
  • Average peak pruritus numeric rating scale (PP-NRS) score ≥4 in the 7 days before randomization.
  • Negative pregnancy tests for women of childbearing potential.

You may not qualify if:

  • Part A and B:
  • Significant health issues, such as positive tests for human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), active tuberculosis, immunodeficiencies or autoimmune diseases.
  • History of major metabolic, liver, kidney, hematologic or other significant disorders.
  • Abnormal Electrocardiogram (ECG) findings
  • Clinically relevant abnormal lab results, including low blood counts, or abnormal liver and kidney function.
  • History of drug abuse or addiction within 6 months prior to screening
  • Current smoker or use of any nicotine or tobacco containing products within the last 6 months prior to dosing.
  • Donated \>500mL blood within 2 months of dosing.
  • For Part B only:
  • Presence of dermatologic conditions and/or comorbidities that might confound the diagnosis of AD and/or might interfere with study assessments.
  • Uncontrolled chronic disease that might require bursts of oral corticosteroids.
  • Any other sound medical, psychiatric, and/or social reason as determined by the investigator.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (12)

Veracity Clinical Research

Woolloongabba, Queensland, Australia

RECRUITING

Skin Health Institute

Carlton, Victoria, Australia

RECRUITING

Peking University Third Hospital

Beijing, Beijing Municipality, China

RECRUITING

Shandong Provincial Dermatology Hospital

Jinan, Shandong, China

RECRUITING

Shanghai Skin Disease Hospital

Shanghai, Shanghai Municipality, China

RECRUITING

Hangzhou First People's Hospital

Hangzhou, Zhejiang, China

RECRUITING

Aotearoa Clinical Trials

Auckland, Auckland, New Zealand

RECRUITING

Momentum Auckland

Takapuna, Auckland, New Zealand

RECRUITING

Momentum Hamilton

Hamilton, Hamilton, New Zealand

RECRUITING

Momentum Palmerston North

Palmerston North, Mananwatu, New Zealand

RECRUITING

Momentum Hutt Valley

Upper Hutt, Wellington Region, New Zealand

RECRUITING

Momentum Kapiti

Waikanae, Wellington Region, New Zealand

RECRUITING

MeSH Terms

Conditions

Dermatitis, Atopic

Condition Hierarchy (Ancestors)

Skin Diseases, GeneticGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and AbnormalitiesDermatitisSkin DiseasesSkin and Connective Tissue DiseasesSkin Diseases, EczematousHypersensitivity, ImmediateHypersensitivityImmune System Diseases

Central Study Contacts

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

November 14, 2025

First Posted

November 19, 2025

Study Start

December 1, 2025

Primary Completion (Estimated)

December 28, 2027

Study Completion (Estimated)

December 28, 2027

Last Updated

August 7, 2026

Record last verified: 2025-12

Data Sharing

IPD Sharing
Will not share

Locations