Celldex Therapeutics, Inc. announced that patient enrollment has been completed in the Company's Phase 2 clinical study of barzolvolimab for the treatment of the two most common forms of chronic inducible urticaria (CIndU)--cold urticaria (ColdU) and symptomatic dermatographism (SD). CIndU is characterized by the occurrence of hives or wheals that have an attributable trigger associated with them--temperatures below skin temperature in ColdU and scratching/rubbing of the skin in SD.ast cell activation is known to be a critical driver in ColdU and SD. Barzolvolimab is a humanized monoclonal antibody that specifically binds the receptor tyrosine kinase KIT with high specificity and potently inhibits its activity, which is required for mast cell function and survival.

In February 2024, the Company presented positive 12 week primary endpoint results from its ongoing Phase 2 study of barzolvolIMab in the most common form of chronic urticaria--chronic spontaneous urticaria (CSU). The randomized, double-blind, placebo-controlled, parallel group Phase 2 study is evaluating the efficacy and safety profile of multiple dose regimens of barzolvolimab in patients with CIndU who remain symptomatic despite antihistamine therapy, to determine the optimal dosing strategy. 196 patients in 2 cohorts (differentiated by CIndU subtype) including 97 patients with ColdU and 99 patients with SD were randomly assigned on a 1:1:1 ratio to receive subcutaneous injections of barzolvolimab at 150 mg every 4 weeks, 300 mg every 8 weeks or placebo during a 20-week treatment phase.

Patients then enter a follow-up phase for an additional 24 weeks. The primary endpoint of the study is the percentage of patients with a negative provocation test at Week 12 (using TempTest® for ColdU and FricTest® for SD). Secondary endpoints include safety and other assessments of clinical activity including CTT (critical temperature threshold), CFT (critical friction threshold) and WI-NRS (worst itch numeric rating scale).