A Phase 1 Study of GTX-B001 in Healthy Subjects and Patients With Chronic Inducible Urticaria

NCT07181369 | Recruiting Phase 1

• 2 other identifiers: GRN-GTXB001-0012025-522126-13-00
• Study Type: interventional
• Target: 72
• Locations: 1 country
• Sites: 2

Brief Summary

This is a first-in-human study aimed at determining the safety of a single dose of GTX-B001 in healthy participants and in people with chronic inducible urticaria.

Conditions

Healthy Subjects; Cold Urticaria; Symptomatic Dermographism; Chronic Inducible Urticaria

Keywords

Urticaria; Skin diseases; Mast cells; Bispecific antibody; GTX-B001; Infusion; Single Ascending Dose; Healthy subjects; Safety; Pharmacokinetics; Pharmacodynamics; Cold urticaria; Intravenous; symptomatic dermographism

Outcome Measures

Primary Outcomes (1)

• Safety as assessed by the incidence and severity of adverse events (Parts A and B)

  Safety and tolerability of a single intravenous infusion of GTX-B001 as assessed by the percentage of subjects at each dose level with Grade 2 or higher adverse events as assessed by the Common Terminology Criteria for Adverse Events (CTCAE).

  Day 1 to Day 85

Secondary Outcomes (1)

• GTX-B001 pharmacokinetics (Parts A and B)

  Day 1 to Day 85

Other Outcomes (10)

• GTX-B001 pharmacodynamics (Parts A and B)

  Day 1 to Day 85

• GTX-B001 pharmacodynamics in skin (Part B)

  Day 1 to Day 29

• Evaluation of immunogenicity (Parts A and B)

  Day 1 to Day 85

Study Arms (4)

Part A (HV) - GTX-B001

EXPERIMENTAL

Healthy participants will receive a single dose of GTX-B001

Drug: GTX-B001

Part A (HV) - Normal Saline

PLACEBO COMPARATOR

Healthy participants assigned to receive placebo will receive a single dose of normal saline

Drug: Normal Saline

Part B (ColdU/SD) - GTX-B001

EXPERIMENTAL

Patients with cold urticaria or symptomatic dermographism will receive a single dose of GTX-B001

Drug: GTX-B001

Part B (ColdU/SD) - Normal Saline

PLACEBO COMPARATOR

Patients with cold urticaria or symptomatic dermographism assigned to receive placebo will receive a single dose of normal saline

Drug: Normal Saline

Interventions

GTX-B001 DRUG

Single infusion of one of up to five dosages of GTX-B001

Also known as: ALY-301

Part A (HV) - GTX-B001; Part B (ColdU/SD) - GTX-B001

Normal Saline DRUG

Single infusion of normal saline

Part A (HV) - Normal Saline; Part B (ColdU/SD) - Normal Saline

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• The subject is between 18 and 55 years of age (both inclusive) at the date of screening.
• The subject is in good general health based on the medical history, physical examination and the results of vital signs, electrocardiogram and clinical laboratory, as judged by the investigator.
• The subject is between 18 and 75 years of age (both inclusive) at the date of screening
• A history of signs and/or symptoms of ColdU or SD experienced ≥ 3 months prior to screening.
• For ColdU patients, a positive provocation test during screening and baseline, using the TempTest® device.
• For SD patients, a positive provocation test with at least 3 pins during screening and baseline, using the FricTest® device.
• Inadequate control of ColdU or SD by second generation H1-antihistamine (sgAH) as defined as the presence of itch and hives following a trigger (e.g. cold or scratching, respectively) within the last 6 weeks prior to screening in spite of use of a sgAH.
• A Urticaria Control Test (UCT) score of \< 12 at screening.

You may not qualify if:

• Presence of any clinically significant illness, such as cardiovascular, neurologic, pulmonary, hepatic, renal, metabolic, gastrointestinal, urologic, immunologic, or endocrine disease or disorder that would interfere with the patient's safety or the interpretation of trial results in the judgment of the investigator.
• Treatment with an investigational drug or intervention for any condition within three months of screening, or concurrent participation in another clinical trial in which an investigational drug is administered.
• Treatment with immunomodulating therapy (e.g., intravenous or intramuscular immunoglobulins, systemic corticosteroids, cyclosporine, methotrexate, dapsone, cyclophosphamide, tacrolimus, mycophenolate mofetil, hydroxychloroquine, infliximab, adalimumab, etanercept, etc.) within 4 weeks (or 5 half-lives, whichever is longer) prior to screening.
• Use of any monoclonal antibody or therapeutic protein within 4 weeks (or 5 half-lives, whichever is longer) prior to screening.
• History of anaphylaxis, autoimmune disorders requiring more than topical medication, or asthma requiring regular use of inhaled medication within the past 5 years, unless, in the opinion of the Investigator, the condition is not considered clinically significant and is unlikely to affect subject safety or study outcomes.
• Additionally for Part B:
• Disease with symptoms of urticaria or angioedema other than Chronic Urticaria (CU), for example urticaria vasculitis, erythema multiforme, mastocytosis, or drug-induced urticaria. Patients with concomitant Chronic Spontaneous Urticaria (CSU) or other forms of Chronic Inducible Urticaria (CIndU) are eligible provided that symptoms at screening are consistent with ColdU or SD and that ColdU or SD is the dominant form of CU.
• Any other skin disease associated with chronic itching that might influence in the investigators' opinion of the study evaluations and results, e.g., atopic dermatitis, bullous pemphigoid, dermatitis herpetiformis, or psoriasis.
• Receipt of any biologic therapy for urticaria control (e.g. omalizumab, dupilumab, ligelizumab, etc.) within three months of screening (whether on-label or off-label).

Sponsors & Collaborators

• Granular Therapeutics Limited: lead

Study Sites (2)

Charité Research Organization gmbh

Berlin, Germany

RECRUITING

Fraunhofer Institute For Translational Medicine And Pharmacology

Berlin, Germany

NOT YET RECRUITING

MeSH Terms

Conditions

Cold Urticaria; Familial dermographism; Chronic Inducible Urticaria; Urticaria; Skin Diseases

Interventions

Saline Solution

Condition Hierarchy (Ancestors)

Skin Diseases, Vascular; Skin and Connective Tissue Diseases; Hypersensitivity, Immediate; Hypersensitivity; Immune System Diseases; Chronic Urticaria; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Crystalloid Solutions; Isotonic Solutions; Solutions; Pharmaceutical Preparations

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Single Ascending Dose

Study Record Dates

• First Submitted: September 12, 2025
• First Posted: September 18, 2025
• Study Start: October 6, 2025
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): August 1, 2027
• Last Updated: January 30, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

DE (2)