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.
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
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).