A Study to Evaluate the Efficacy and Safety of AK139 in Patients With Moderate-to-severe Atopic Dermatitis

A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group, Multicenter Phase II Clinical Trial to Evaluate the Efficacy and Safety of AK139 in Patients With Moderate to Severe Atopic Dermatitis

This is a randomized, double-blind phase II clinical study to evaluate the efficacy and safety of AK139 in the treatment of patients with moderate-to-severe atopic dermatitis.

Study Overview

• Status: Not yet recruiting
• Conditions: Moderate-to-Severe Atopic Dermatitis
• Intervention / Treatment: Biological: AK139 and placebo; Biological: AK139 and placebo; Biological: AK139 and placebo; Biological: AK139 and placebo; Biological: AK139; Biological: AK139; Biological: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 168
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Guoqin Wang; Phone Number: +86 (0760) 8987 3999; Email: global.trials@akesobio.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Able to understand the study and voluntarily sign the ICF.
2. Atopic dermatitis (AD) diagnosed at least 6 months before screening.
3. Eczema Area and Severity Index (EASI) score ≥16, Investigator's Global Assessment (IGA) score ≥3, and Body surface area (BSA) involvement ≥10% at both screening and baseline.
4. A weekly average of daily Peak Pruritus Numerical Rating Scale (P-NRS) score ≥4 at baseline.
5. Inadequate response or intolerance to prior topical therapy for AD.
6. The patients agree to use highly effective contraception methods from the moment of signing of the ICF to 90 days after the last dose of the investigational product.

Exclusion Criteria:

1. Acute onset of AD within the first 4 weeks of randomization.
2. Received systemic corticosteroids, immunosuppressive/immunomodulatory drugs, phototherapy or other systemic therapies used for AD within the 4 weeks before randomization.
3. Received treatment with other clinical research drugs (non-biological agents) within the first 4 weeks or 5 half-lives of randomization (whichever is longer)
4. Received or planned to receive live vaccine treatment within the 12 weeks before randomization or during the study period.
5. Received allergen specific immunotherapy within the 12 weeks before randomization.
6. Have a history of allergies to any component of AK139 and/or severe allergic reactions to monoclonal antibodies.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

7

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Part 2: Placebo	Biological: Placebo; Placebo-subcutaneous injection
Experimental: Part 1: AK139 regimen 1	Biological: AK139 and placebo; AK139 plus placebo regimen 1-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 3-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 5-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 6-subcutaneous injection.
Experimental: Part 1: AK139 regimen 2	Biological: AK139; AK139 regimen 2-subcutaneous injection.; Biological: AK139; AK139 regimen 4-subcutaneous injection.
Experimental: Part 1: AK139 regimen 3	Biological: AK139 and placebo; AK139 plus placebo regimen 1-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 3-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 5-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 6-subcutaneous injection.
Experimental: Part 1: AK139 regimen 4	Biological: AK139; AK139 regimen 2-subcutaneous injection.; Biological: AK139; AK139 regimen 4-subcutaneous injection.
Experimental: Part 2: AK139 regimen 5	Biological: AK139 and placebo; AK139 plus placebo regimen 1-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 3-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 5-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 6-subcutaneous injection.
Experimental: Part 2: AK139 regimen 6	Biological: AK139 and placebo; AK139 plus placebo regimen 1-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 3-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 5-subcutaneous injection.; Biological: AK139 and placebo; AK139 plus placebo regimen 6-subcutaneous injection.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Incidence and severity grading of Adverse Events (AE)(applicable to Part 1)	Up to Week 16 (applicable to the Q4W dosing group); Up to Week 8 (applicable to the Q2W dosing group).
Percentage of patients who achieved Eczema Area and Severity Index (EASI)-75 (applicable to Part 2)	at week 16

Secondary Outcome Measures

Outcome Measure	Time Frame
Percentage of patients achieving an IGA score of 0 or 1 at each visit, with a reduction of ≥2 points from baseline	Up to Week 24
Percentage change in affected Body Surface Area (BSA)	Up to week 24
Percentage change of Peak Pruritus Numerical Rating Scale (P-NRS) scores	Up to week 24
Percentage changes in the Dermatology Life Quality Index (DLQI) score	Up to week 24

Collaborators and Investigators

• Sponsor: Akeso

Study record dates

Study Major Dates

• Study Start (Estimated): April 7, 2026
• Primary Completion (Estimated): November 1, 2027
• Study Completion (Estimated): January 10, 2028

Study Registration Dates

• First Submitted: March 25, 2026
• First Submitted That Met QC Criteria: March 25, 2026
• First Posted (Actual): March 30, 2026

Study Record Updates

• Last Update Posted (Actual): March 30, 2026
• Last Update Submitted That Met QC Criteria: March 25, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: AK139-205

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