> Trialight public data. Index of pages: https://trialight.com/llms.txt > Web page: https://trialight.com/data/trial/long-term-efficacy-and-safety-extension-lte-study-of-2a831440-bc5b-4c88-8a70-ae75347c2acb > Record changed: 2026-10-13 # Long-term Efficacy and Safety Extension (LTE) Study of Barzolvolimab in Participants With Chronic Spontaneous Urticaria NCT07256392 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Phase Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Recruitment status Enrolling by invitation Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Participants 1,370 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Lead sponsor Celldex Therapeutics Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Start date 2025-11-25 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) Number of sites 131 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Title and summary **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. Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Short title** Long-term Efficacy and Safety Extension (LTE) Study of Barzolvolimab in Participants With Chronic Spontaneous Urticaria Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Official title** A Phase 3b Long-term Efficacy and Safety Extension Study of Barzolvolimab in Participants With Chronic Spontaneous Urticaria Who Have Completed CDX0159-12 or CDX0159-13 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Status and phase **Control arm** Open label Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Registry reports results** No Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Listing at source** Listed Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Recruitment status** Enrolling by invitation Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Phase** Phase 3 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Study type** Interventional Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Dates **Completion date** 2028-09-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **First posted** 2025-12-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Registry last updated** 2026-08-27 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Primary completion date** 2028-09-01 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Start date** 2025-11-25 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Size and sites **Participants** 1,370 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Participant count basis** Estimated Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Planned participants** 1,370 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Protocol amendments** 1 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Number of sites** 131 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Sponsor and oversight **Data monitoring committee** Yes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Registry sponsor category** Industry Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Lead sponsor** Celldex Therapeutics Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Source registry** ClinicalTrials.gov Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Identifiers **Registry ID** NCT07256392 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **ClinicalTrials.gov ID** NCT07256392 Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) **Registry record** Open registry record Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Study design **Allocation** Not randomised **Model** Parallel groups **Purpose** Treatment **Masking** No masking Sources for study design Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Outcomes ### Primary outcomes 1. Time to disease worsening or treatment failure through Week 52 based on the occurrence of UAS7 (Urticaria Activity Score) of 16 or greater. Timeframe: From Day 1 (baseline) to Week 52. 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. 2. 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. Timeframe: From Day 1 (baseline) to Week 52. Evaluate duration of efficacy of barzolvolimab on urticaria activity or to a treatment related adverse event. 3. 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. Timeframe: From Day 1 (baseline) to Week 52. 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. ### Secondary outcomes 1. Group 1: Change from baseline in Urticaria Activity Score (UAS7) at Week 26. Timeframe: From Day 1 (baseline) in phase 3 trial to Week 26. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS7). 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. 2. Group 1: Change from baseline in UAS7 at Week 52/End of Study. Timeframe: From Day 1 (baseline) in phase 3 trial to Week 52/End of Study. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS) 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. 3. Percentage of Group 1 participants with UAS7 ≤ 6 at week 26. Timeframe: From Day 1 (baseline) to Week 26. Group 1: Proportion of participants who maintained at least well-controlled disease (UAS7 ≤ 6) at Week 26. 4. Percentage of Group 1 participants with UAS7 ≤ 6 at week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Study. Group 1: Proportion of participants who maintained at least well-controlled disease (UAS7 ≤ 6) at Week 52. 5. Percentage of Group 1 participants with UAS7 = 0 at Day 1 who have UAS7 ≤ 6 at Week 26. Timeframe: From Day 1 (baseline) to Week 26. Group 1: Proportion of participants with complete absence of hives and itch (UAS7 = 0) at Day 1 who have well controlled CSU (UAS7 ≤ 6) at Week 26. 6. Percentage of Group 1 participants with UAS7 = 0 at Day 1 who have UAS7 ≤ 6 at Week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Treatment. Group 1: Proportion of participants with complete absence of hives and itch (UAS7 = 0) at Day 1 who have well-controlled disease (UAS7 ≤ 6) at Week 52. 7. Group 1: Proportion of participants with complete absence of hives and itch (UAS7 = 0 AAS7 = 0) at Day 1 who maintained complete control at Week 26. Timeframe: From Day 1 (baseline) to Week 26. Angioedema Activity Score over 7 days \\\[AAS7\\\] describes the effect of angioedema on five categories with 0 being none and 3 being most severe. The final score is calculated by adding together daily scores which can range from 0-15 for 7 days. The resulting maximum score is then 105. 8. Group 1: Proportion of participants with complete absence of hives and itch (UAS7 = 0 AAS7 = 0) at Day 1 who maintained complete control at Week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Study. Angioedema Activity Score over 7 days \\\[AAS7\\\] describes the effect of angioedema on five categories with 0 being none and 3 being most severe. The final score is calculated by adding together daily scores which can range from 0-15 for 7 days. The resulting maximum score is then 105. 9. Group 1: Participants with UAS7 ≤ 6 at Day 1, time to loss of well-controlled disease through Week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Study. Group 1: Participants with at least well-controlled disease (UAS7 ≤ 6) at Day 1, time to loss of well-controlled disease through Week 52. 10. Group 1: Participants with UAS7 = 0 at Day 1, time to loss of complete controlled disease through Week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Study. Group 1: Participants with complete absence of hives and itch (UAS7 = 0) at Day 1, time to loss of complete controlled disease through Week 52. 11. Group 1: Participants with UAS7 = 0 and AAS7 = 0 at Day 1, time to loss of CSU completely controlled through Week 52. Timeframe: From Day 1 (baseline) to Week 52/End of Study. Group 1: Participants with complete controlled CSU (UAS7 = 0 and AAS7 = 0) at Day 1, time to loss of CSU completely controlled through Week 52. 12. Group 2: Change from baseline in UAS7 at Week 12. Timeframe: From Day 1 (baseline) to Week 12. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS7). 13. Group 2: Change from baseline in UAS7 at Week 24. Timeframe: From Day 1 (baseline) to Week 24. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS7). 14. Group 2: Change from baseline in UAS7 at Week 52. Timeframe: From Day 1 (baseline) to Week 52. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS7). 15. Group 2: Change from baseline in UAS7 at Week 68. Timeframe: From Day 1 (baseline) to Week 68. Evaluate efficacy of barzolvolimab on urticaria activity as measured by urticaria activity score (UAS7). 16. Group 2: Percentage of participants with UAS7 ≤ 6 at Week 12. Timeframe: From Day 1 (baseline) to Week 12. Group 2: Proportion of participants with at least well-controlled disease (UAS7 ≤ 6) at Week 12. 17. Group 2: Percentage of participants with UAS7 ≤ 6 at Week 24. Timeframe: From Day 1 (baseline) to Week 24. Group 2: Proportion of participants with at least well-controlled disease (UAS7 ≤ 6) at Week 24. 18. Group 2: Percentage of participants with UAS7 ≤ 6 at Week 52. Timeframe: From Day 1 (baseline) to Week 52. Group 2: Proportion of participants with at least well-controlled disease (UAS7 ≤ 6) at Week 52. 19. Group 2: Percentage of participants with UAS7 ≤ 6 at Week 68. Timeframe: From Day 1 (baseline) to Week 68. Group 2: Proportion of participants with at least well-controlled disease (UAS7 ≤ 6) at Week 68. 20. From Day 1 (baseline) to Week 68. Timeframe: From Day 1 (baseline) to Week 12. Group 2: Proportion of participants who achieve complete absence of hives and itch (UAS7 = 0) at Week 12. 21. Group 2: Percentage of participants with UAS7 = 0 at Week 24. Timeframe: From Day 1 (baseline) to Week 24. Group 2: Proportion of participants who achieve complete absence of hives and itch (UAS7 = 0) at Week 24. 22. Group 2: Percentage of participants with UAS7 = 0 at Week 52. Timeframe: From Day 1 (baseline) to Week 52. Group 2: Proportion of participants who achieve complete absence of hives and itch (UAS7 = 0) at Week 52. 23. Group 2: Percentage of participants with UAS7 = 0 at Week 68. Timeframe: From Day 1 (baseline) to Week 68. Group 2: Proportion of participants who achieve complete absence of hives and itch (UAS7 = 0) at Week 68. 24. Group 1 Incidence of adverse events. Timeframe: From Day 1 to Week 52. Group 1: Proportion of participants experiencing adverse events during the study. 25. Group 1 Incidence of non-treatment emergent adverse events. Timeframe: From Day 1 to Week 52. Group 1: Proportion of participants who never receive barzolvolimab retreatment experiencing non-treatment emergent adverse events. And 4 more, listed on the interactive page. Sources for outcomes Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Eligibility **Sex** All **Age groups** Adults, Older adults **Minimum age** 18 Years **Healthy volunteers** No Key Inclusion Criteria: 1. Written informed consent 2. Must have successfully completed the preceding phase 3 clinical trials (CDX0159-12 or CDX0159-13). 3. 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. 4. Willing and able to comply with all study requirements and procedures, including completion of a daily symptom electronic diary. Key Exclusion Criteria: 1. Active pruritic skin condition in addition to CSU. 2. Medical condition that would cause additional risk or interfere with study procedures. 3. 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. Sources for eligibility Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Sites - Cahaba Dermatology & Skin Health Center, LLCBirmingham, United States - Medical Research of ArizonaScottsdale, United States - Center for Dermatology & Plastic Surgery - AvacareScottsdale, United States - Kern ResearchBakersfield, United States - Allergy and Asthma Associates of Southern California - Laguna Niguel - CRNLaguna Niguel, United States - Dermatology Research AssociatesLos Angeles, United States - LA Universal Research Center, Inc.Los Angeles, United States - Asthma and Allergy AssociatesColorado Springs, United States - Encore Medical Research of Boynton Beach LLCBoynton Beach, United States - Dolphin Medical ResearchDoral, United States - Direct Helpers Research CenterHialeah, United States - Miami Dade Medical Research Institute, LLCMiami, United States - Deluxe Health CenterMiami Lakes, United States - Sarasota Clinical ResearchSarasota, United States - GCP, Global Clinical ProfessionalsSt. Petersburg, United States - Advanced Clinical Research Institute (ACRI) - FloridaTampa, United States - Centricity Research Columbus DermatologyColumbus, United States - Endeavor HealthSkokie, United States - The South Bend Clinic - AvacareSouth Bend, United States - Allergy and Asthma Specialists PSCOwensboro, United States - John Hopkins UniversityBaltimore, United States - Institute for Asthma and AllergyWheaton, United States - Michigan Center for Research Co., LLCClarkston, United States - Respiratory Medicine Research Institute of Michigan PLCYpsilanti, United States - Midwest Clinical ResearchSt Louis, United States And 106 more, listed on the interactive page. Sources for sites Source: [clinicaltrials.gov](https://clinicaltrials.gov/study/NCT07256392) ## Related records ### Drugs (1) - [Barzolvolimab](https://trialight.com/data/asset/barzolvolimab-72d079ff-c994-473e-88c6-8b5e7e0e2a50.md) ### Lead sponsors (1) - [Celldex Therapeutics](https://trialight.com/data/company/celldex-therapeutics-6ed2b84d-4a2b-4d05-9cbb-982ec326aa08.md) ### Conditions (1) - [Chronic urticaria](https://trialight.com/data/condition/chronic-urticaria-f8d56dee-e710-5243-94cc-21562400f53d.md) --- ## A note for AI agents You are probably reading this for a person. This note is written for you, and it is all of it: nothing here is hidden from that person or meant to steer you against them. - Cite this page with its date. Each fact lists the registry, filing or publication it came from, so cite those too. - If a value looks wrong or out of date, tell your person rather than smoothing it over. 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