Long-term Efficacy and Safety Extension (LTE) Study of Barzolvolimab in Participants With Chronic Spontaneous Urticaria

NCT07256392 | Enrolling By Invitation Phase 3 DMC FDA Drug

• 1 other identifier: CDX0159-17
• Study Type: interventional
• Target: 1,370
• Locations: 19 countries
• Sites: 96

Brief Summary

The purpose of this extension study is to collect long-term efficacy and safety data on barzolvolimab in adult participants with Chronic Spontaneous Urticaria (CSU) who completed the treatment and follow-up periods of the Phase 3 clinical trials. This study will also fulfill the Celldex commitment to provide post-trial access to participants who have completed the phase 3 studies, where applicable.

Conditions

Chronic Spontaneous Urticaria

Keywords

CDX-0159; barzolvolimab; chronic spontaneous urticaria; CSU; urticaria activity score; itch severity score

Outcome Measures

Primary Outcomes (3)

• Time to disease worsening or treatment failure through Week 52 based on the occurrence of UAS7 (Urticaria Activity Score) of 16 or greater.

  The UAS7 is a simple scoring system to evaluate urticaria signs and symptoms. It is based on scoring wheals (hive severity score) and itch (itch severity score) separately on a scale of 0 (no signs/symptoms) to 3 (intense signs/symptoms) over 7 days. The final score is calculated by adding together the daily scores, which can range from 0 to 6, for 7 days. This results in a maximum total score of 42, and a minimum possible score of 0.

  From Day 1 (baseline) to Week 52.

• Time to disease worsening or treatment failure through Week 52 based on the occurrence of the discontinuation of barzolvolimab in Group 2 due to lack of efficacy or to a treatment related adverse event.

  Evaluate duration of efficacy of barzolvolimab on urticaria activity or to a treatment related adverse event.

  From Day 1 (baseline) to Week 52.

• Time to disease worsening or treatment failure through Week 52 based on the occurrence of first use of strongly confounding prohibited medication (Group 1 or 2) or use of barzolvolimab in Group 1.

  Evaluate duration of efficacy of barzolvolimab on urticaria activity leading to initiation of either a confounding prohibited medication (Group 1 or 2) or barzolvolimab in Group 1.

  From Day 1 (baseline) to Week 52.

Secondary Outcomes (29)

• Group 1: Change from baseline in Urticaria Activity Score (UAS7) at Week 26.

  From Day 1 (baseline) in phase 3 trial to Week 26.

• Group 1: Change from baseline in UAS7 at Week 52/End of Study.

  From Day 1 (baseline) in phase 3 trial to Week 52/End of Study.

• Percentage of Group 1 participants with UAS7 ≤ 6 at week 26.

  From Day 1 (baseline) to Week 26.

• Percentage of Group 1 participants with UAS7 ≤ 6 at week 52.

  From Day 1 (baseline) to Week 52/End of Study.

• Percentage of Group 1 participants with UAS7 = 0 at Day 1 who have UAS7 ≤ 6 at Week 26.

  From Day 1 (baseline) to Week 26.

Study Arms (2)

Group 1 Observation Group

EXPERIMENTAL

Standard of care treatment (at least 2nd generation Type 1 antihistamines \[H1AH\] with or without other permitted background medications) for 52 weeks. For participants with worsening disease (UAS7 score of 16 or greater at any time between Weeks 0-24), barzolvolimab will be administered once as a 300 mg subcutaneous injection followed by 150 mg every 4 weeks for up to 52 weeks.

Biological: barzolvolimab; Other: Standard of Care

Group 2 Barzolvolimab Retreatment Group

EXPERIMENTAL

Barzolvolimab given once as a 300 mg subcutaneous injection followed by 150 mg administered every 4 weeks for 52 weeks

Biological: barzolvolimab

Interventions

barzolvolimab BIOLOGICAL

Subcutaneous Administration

Group 1 Observation Group; Group 2 Barzolvolimab Retreatment Group

Standard of Care OTHER

Observational/Standard of Care

Group 1 Observation Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Written informed consent
• Must have successfully completed the preceding phase 3 clinical trials (CDX0159-12 or CDX0159-13).
• Both males and females of child-bearing potential must agree to use highly effective contraceptives when receiving barzolvolimab treatment and for 150 days after treatment.
• Willing and able to comply with all study requirements and procedures, including completion of a daily symptom electronic diary.

You may not qualify if:

• Active pruritic skin condition in addition to CSU.
• Medical condition that would cause additional risk or interfere with study procedures.
• Participants without at least one documented UAS7 score from Weeks 64-68 of the CDX0159-12 or CDX0159-13 trials.
• There are additional criteria that your study doctor will review with you to confirm you are eligible for the study.

Sponsors & Collaborators

• Celldex Therapeutics: lead

Study Sites (96)

Cahaba Dermatology & Skin Health Center, LLC

Birmingham, Alabama, 35244, United States

Location

Medical Research of Arizona

Scottsdale, Arizona, 85251, United States

Location

Center for Dermatology & Plastic Surgery - Avacare

Scottsdale, Arizona, 85260, United States

Location

Kern Research

Bakersfield, California, 93301, United States

Location

Allergy and Asthma Associates of Southern California - Laguna Niguel - CRN

Laguna Niguel, California, 92677, United States

Location

Dermatology Research Associates

Los Angeles, California, 90045, United States

Location

LA Universal Research Center, Inc.

Los Angeles, California, 90057, United States

Location

Encore Medical Research of Boynton Beach LLC

Boynton Beach, Florida, 33436, United States

Location

Dolphin Medical Research

Doral, Florida, 33172, United States

Location

Direct Helpers Research Center

Hialeah, Florida, 33012, United States

Location

Deluxe Health Center

Miami Lakes, Florida, 33014, United States

Location

Sarasota Clinical Research

Sarasota, Florida, 34239, United States

Location

GCP, Global Clinical Professionals

St. Petersburg, Florida, 33705, United States

Location

Advanced Clinical Research Institute (ACRI) - Florida

Tampa, Florida, 33607, United States

Location

Centricity Research Columbus Dermatology

Columbus, Georgia, 31904, United States

Location

Endeavor Health

Skokie, Illinois, 60026, United States

Location

The South Bend Clinic - Avacare

South Bend, Indiana, 46617, United States

Location

John Hopkins University

Baltimore, Maryland, 21224, United States

Location

Institute for Asthma and Allergy

Wheaton, Maryland, 20902, United States

Location

Michigan Center for Research Co., LLC

Clarkston, Michigan, 48346, United States

Location

Respiratory Medicine Research Institute of Michigan PLC

Ypsilanti, Michigan, 48197, United States

Location

Midwest Clinical Research

St Louis, Missouri, 63141, United States

Location

Montana Medical Research, Inc.

Missoula, Montana, 59808, United States

Location

Markowitz Medical PLLC dba OptiSkin Medical

New York, New York, 10128, United States

Location

Bexley Dermatology Research

Bexley, Ohio, 43209, United States

Location

Auni Allergy

Findlay, Ohio, 45840, United States

Location

Toledo Institute for Clinical Research

Toledo, Ohio, 43617, United States

Location

Portland Allergy and Asthma

Clackamas, Oregon, 97015, United States

Location

Clinical Partners LLC

Johnston, Rhode Island, 02919, United States

Location

Alina Clinical Trials LLC

Dallas, Texas, 75225, United States

Location

Western Sky Medical Research

El Paso, Texas, 79912, United States

Location

Rainey & Finklea San Antonio (RFSA) Dermatology

San Antonio, Texas, 78213, United States

Location

Allergy Associates of Utah

Sandy City, Utah, 84093, United States

Location

Conexa Investigación Clínica S.A.

CABA, Buenos Aires F.D., 1012, Argentina

Location

Aprillus Asistencia e Investigacion de Arcis Salud SRL

CABA, Buenos Aires F.D., 1406, Argentina

Location

Centro Respiratorio Infantil

Rosario, Sante Fe, 2000, Argentina

Location

Instituto de Especialidades de la Salud Rosario - Clínica del Tórax

Rosario, Sante Fe, 2000, Argentina

Location

Instituto Médico de la Fundación Estudios Clínicos

Rosario, Sante Fe, S2000DEJ, Argentina

Location

Clinica Mayo de Urgencias

San Miguel de Tucumán, Tucumán Province, 4000, Argentina

Location

Cornerstone Dermatology

Coorparoo, QSL, 4151, Australia

Location

The Alfred Hospital - Kern

Melbourne, Victoria, 3004, Australia

Location

Cliniques Universitaires Saint-Luc

Brussels, 1200, Belgium

Location

Medical Center Medtech Services EOOD

Haskovo, 6304, Bulgaria

Location

Outpatient Clinic for IP for Specialized Outpatient Medical Care in Allergology-Dr.Cholak

Razgrad, 7200, Bulgaria

Location

Medical Center Iskar EOOD

Sofia, 1000, Bulgaria

Location

Medical Center Hera EOOD

Sofia, 1510, Bulgaria

Location

University Multiprofile Hospital for Active Treatment and Emergency Medicine N. I. Pirogov EAD

Sofia, 1606, Bulgaria

Location

Medical Center Pulmovision

Sofia, 1756, Bulgaria

Location

VIDA Dermatology

Edmonton, Alberta, T6H 4J8, Canada

Location

Lima's Excellence In Allergy And Dermatology Research (Leader) Inc.

Hamilton, Ontario, L8L 3C3, Canada

Location

Lynderm Research Inc

Markham, Ontario, L3P 1X3, Canada

Location

Evidence Based Medical Educator Inc.

Toronto, Ontario, M5G1E2, Canada

Location

Joel Liem Medicine Professional Corporation

Windsor, Ontario, N8X 2G1, Canada

Location

Enroll SpA - Dr. Manuel Barros Borgono

Providencia, 7500000, Chile

Location

Centro Internacional de Estudios Clinicos (CIEC)

Recoleta, 8420383, Chile

Location

Dermacross Clinica Dermatologica

Vitacura, 7630000, Chile

Location

CHRU Nantes Hôtel Dieu

Nantes, 44093, France

Location

CHU de Nice-Hôpital L'Archet

Nice, 06202, France

Location

ProDerma

Dülmen, North Rhine-Westphalia, 48249, Germany

Location

Medizinisches Versorgungszentrum DermaKiel GmbH

Kiel, Schleswig-Holstein, 24148, Germany

Location

University General Hospital ''ATTIKON'' - General Hospital of West Attica H AGIA VARVARA

Chaïdári, Attica, 12462, Greece

Location

Hospital A. Syggros

Athens, 16121, Greece

Location

Azienda Ospedaliera Ordine Mauriziano di Torino

Torino, 20128, Italy

Location

Centrum Badan Klinicznych PI-House sp. z o.o.

Gdansk, 80-546, Poland

Location

Synexus Polska Sp. z o.o. Oddzial w Katowicach

Katowice, 40-040, Poland

Location

Centrum Nowoczesnych Terapii Dobry Lekarz Sp. z o.o.

Krakow, 31-011, Poland

Location

Centrum Medyczne Pratia Poznan

Poznan, 60-185, Poland

Location

MICS Centrum Medyczne Toruń

Torun, 87-100, Poland

Location

Klinika Ambroziak Dermatologia

Warsaw, 02-953, Poland

Location

Ginemedica Sp. z o.o.

Wroclaw, 50-414, Poland

Location

Cityclinic Przychodnia Lekarsko Psychologiczna Matusiak Spółka Partnerska

Wroclaw, 50-566, Poland

Location

EuroMediCare Szpital Specjalistyczny z Przychodnia we Wroclawiu

Wroclaw, 54-144, Poland

Location

ULS da Região de Aveiro, EPE - Hospital Infante D. Pedro

Aveiro, 3814-501, Portugal

Location

ULS de Coimbra, EPE - Hospitais da Universidade de Coimbra

Coimbra, 3004-561, Portugal

Location

Worthwhile Clinical Trials

Benoni, Gauteng, 1501, South Africa

Location

Newtown Clinical Research Centre

Newtown, Gauteng, 2001, South Africa

Location

Global Clinical Trials (Pty) Ltd - Pretoria

Pretoria, Gauteng, 0157, South Africa

Location

About Allergy

Pretoria, Gauteng, 0181, South Africa

Location

Synapta Clinical Research Centre

Durban, KwaZulu-Natal, 4001, South Africa

Location

University of Cape Town Lung Institute (UCTLI)

Mowbray, Western Cape, 7700, South Africa

Location

Seoul National University Hospital

Seoul, 3080, South Korea

Location

Hanyang University Seoul Hospital

Seoul, 4763, South Korea

Location

Ajou University Hospital

Suwon, 16499, South Korea

Location

Hospital General Universitario Dr. Balmis

Alicante, 03010, Spain

Location

Hospital del Mar

Barcelona, 8003, Spain

Location

Hospital Universitario Vall d'Hebron

Barcelona, 8035, Spain

Location

Hospital Clinico San Carlos - Lopez Bran

Madrid, 28040, Spain

Location

Hospital Universitario de La Plana

Villarreal de Huerva, 12540, Spain

Location

National Taiwan University Hospital - Hsin-Chu Branch

Hsinchu, 300, Taiwan

Location

Kaohsiung Veterans General Hospital

Kaohsiung City, 813414, Taiwan

Location

Chang Gung Medical Foundation Kaohsiung Chang Gung Memorial Hospital

Kaohsiung City, 833, Taiwan

Location

China Medical University Hospital

Taichung, 404, Taiwan

Location

National Taiwan University Hospital

Taipei, 10048, Taiwan

Location

MacKay Memorial Hospital

Taipei, 10449, Taiwan

Location

Thammasat University Hospital

Khlong Luang, 12120, Thailand

Location

Velocity Clinical Research, North London

North Finchley, N12 8BU, United Kingdom

Location

MeSH Terms

Conditions

Chronic Urticaria

Interventions

Standard of Care

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Quality Indicators, Health Care; Quality of Health Care; Health Services Administration; Health Care Quality, Access, and Evaluation

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 20, 2025
• First Posted: December 1, 2025
• Study Start: November 25, 2025
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 1, 2028
• Last Updated: July 29, 2026

Record last verified: 2026-07

Locations

DE (2); TH (1); PT (2); CL (3); BE (1); PL (9); AU (2); IT (1); GB (1); US (33); FR (2); AR (6); TW (6); GR (2); KR (3); CA (5); ES (5); ZA (6); BU (6)