NCT07256392

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

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

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 1,370 (estimated)
• Sponsor: Celldex Therapeutics · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

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.

Detailed description

This is a global, multicenter, long-term extension phase 3b study to determine the time to disease worsening or treatment failure in adult participants with Chronic Spontaneous Urticaria (CSU) who completed the treatment and follow-up periods the phase 3 clinical trials. The study will consist of 2 Groups: Group 1 (Observation Group), comprising participants whose UAS7 score is less than 16 at entry and Group 2 (Barzolvolimab Retreatment Group) comprising participants whose UAS7 score is 16 or greater. Participation in this trial will last for approximately 52 weeks for participants assigned to Group 1 (Observation Group) and who do not receive barzolvolimab during the trial. Participants assigned to Group 1 who require barzolvolimab rescue during the trial will be in the trial for up to 68 weeks. Participants assigned to Group 2 (Barzolvolimab Retreatment Group), trial participation will last for approximately 68 weeks from the start of treatment (Day 1).

Conditions

• Chronic Spontaneous Urticaria

Interventions

Type	Name	Description
BIOLOGICAL	barzolvolimab	Subcutaneous Administration
OTHER	Standard of Care	Observational/Standard of Care

Timeline

• Start date: 2025-11-25
• Primary completion: 2028-09-01
• Completion: 2028-09-01
• First posted: 2025-12-01
• Last updated: 2026-03-31

Locations

15 sites across 1 country: United States

Regulatory

• FDA-regulated drug study