Study of Multiple Ascending Doses (MAD) of M5542 in Participants With Moderate and Severe Eczema

A Phase 1b, Open Label Study Without Comparator to Evaluate the Safety, Tolerability, and Pharmacokinetics of Multiple Ascending Doses (MAD) of M5542 in Patients With Eczema

The main purpose of this study is to evaluate the safety and tolerability of multiple ascending dose (MAD) of M5542 in participants with Eczema.

Study Overview

• Status: Not yet recruiting
• Conditions: Eczema
• Intervention / Treatment: Biological: M5542

• Study Type: Interventional
• Enrollment (Estimated): 56
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Communication Center; Phone Number: +49 6151 72 5200; Email: service@emdgroup.com

Study Locations

• Germany
  • Darmstadt, Germany
    • Research Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Confirmed diagnosis of eczema with an onset of symptoms at least 6 months prior to Screening
• Topical treatments provide inadequate control for at least 4 consecutive weeks within 1 year of the first dose, or documented reason why they were medically inadvisable (for example [e.g.] important side effects or safety risks)
• Other protocol defined inclusion criteria could apply

Exclusion Criteria:

• Any uncontrolled medical conditions, other than eczema that in the opinion of the Investigator, put the participant at unacceptable risk, or will likely interfere with study assessments or data integrity. Other medical conditions should be stable at the time of Screening and be expected to remain stable for the duration of the study
• Other than eczema, the presence of a significant skin morbidity that will influence the Investigator's ability to assess the diagnosis of eczema and/or severity of disease (for example (e.g.) psoriasis, confirmed or suspected cutaneous T cell lymphoma, autoimmune bullous disease, fixed drug reaction, and Stevens Johnson Syndrome, other)
• History of malignancies, or current malignancies (except for fully resected non melanoma skin cancer, and in situ cervical carcinoma) within the past 5 years
• Known history of, or suspected, significant current or any past history of tuberculosis or non tuberculous mycobacterial infections (including a positive QuantiFERON® Tuberculosis Gold blood test within 4 weeks prior to or at the time of Screening)
• Other protocol defined exclusion criteria could apply

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: M5542	Biological: M5542; Participants will receive loading dose of M5542 followed by maintenance doses as determined by the Safety Monitoring Committee (SMC).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Number of Participants with Treatment-emergent Adverse Events (TEAEs), Serious Adverse Events (SAEs), Adverse Events of Special Interest (AESIs) and AEs Leading to Study Intervention Discontinuation	From Day 1 (Baseline) up to end of Safety Follow-Up (Week 29)
Number of Participants with Clinically Significant Changes from Baseline in Safety Laboratory Assessments	From Day 1 (Baseline) up to end of Safety Follow-Up (Week 29)
Number of Participants with Clinically Significant Changes from Baseline in 12-Lead Electrocardiograms (ECGs)	From Day 1 (Baseline) up to end of Safety Follow-Up (Week 29)
Number of Participants with Clinically Significant Changes from Baseline in Vital Signs	From Day 1 (Baseline) up to end of Safety Follow-Up (Week 29)

Secondary Outcome Measures

Outcome Measure	Time Frame
Pharmacokinetic (PK) Serum Concentrations of M5542	Pre-dose on Days 1, 15, 43 and 113; 72 hours post-dose on Day 8; 24 hours post-dose on Day 120; 48 hours post-dose on Day 127; 72 hours post-dose on Days 141, 176 and 197

Collaborators and Investigators

• Sponsor: Merck Healthcare KGaA, Darmstadt, Germany, an affiliate of Merck KGaA, Darmstadt, Germany
• Investigators: Study Director: Medical Responsible, Merck Healthcare KGaA, Darmstadt, Germany, an affiliate of Merck KGaA, Darmstadt, Germany

Publications and helpful links

Helpful Links

• <p>Trial Awareness and Transparency website</p>
• <p>Medical Information Location Map - Med Info Contacts</p>

Study record dates

Study Major Dates

• Study Start (Estimated): December 20, 2026
• Primary Completion (Estimated): August 14, 2028
• Study Completion (Estimated): August 14, 2028

Study Registration Dates

• First Submitted: November 5, 2026
• First Submitted That Met QC Criteria: November 5, 2026
• First Posted (Actual): November 12, 2026

Study Record Updates

• Last Update Posted (Actual): November 12, 2026
• Last Update Submitted That Met QC Criteria: November 5, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Multiple ascending dose (MAD); Cytotoxic t-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig); OX40 ligand (OX40L)
• Additional Relevant MeSH Terms: Skin Diseases; Skin Diseases, Eczematous; Dermatitis; Skin and Connective Tissue Diseases; Eczema
• Other Study ID Numbers: MS554201_0011; 2026-526029-16-00 (Other Identifier: EU CT number)

Plan for Individual participant data (IPD)

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

IPD Plan Description

IPD will not be shared for Phase I interventional or observational studies. Further information on how to request data can be found on our website bit.ly/IPD21.

Drug and device information, study documents

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