Celldex presents 12-week results from Barzolvolimab Phase 2 study in CSU

Celldex Therapeutics announced positive 12-week results from the company’s Phase 2 clinical trial of barzolvolimab in patients with moderate to severe chronic spontaneous urticaria, or CSU, refractory to antihistamines, including patients with biologic-refractory disease. The studies will continue dosing patients until week 52. 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. CSU is characterized by the occurrence of hives or wheals for 6 weeks or longer without identifiable specific triggers or causes. Treatment options for patients with CSU are limited and there are no approved therapies for patients who are not adequately controlled by omalizumab. Data from the 208 patients randomized in the study showed that barzolvolimab achieved the primary efficacy endpoint, with a statistically significant mean change from baseline to week 12 in UAS7, or weekly urticaria activity score, compared to placebo at all dose levels. Secondary and exploratory endpoints in the study were also achieved at week 12 and strongly support the primary endpoint results, including changes in ISS7, or weekly itch severity score, and HSS7, or weekly hives severity score, and responder analyses. Importantly, barzolvolimab demonstrated rapid, durable and clinically meaningful responses in patients with moderate to severe CSU refractory to antihistamines, including patients with prior omalizumab treatment. Demographics and baseline disease characteristics were well balanced across treatment groups. The majority of patients on study had severe disease. Barzolvolimab demonstrated strong improvement in UAS7 independent of omalizumab status at Week 12. Approximately 20% of enrolled patients received prior treatment with omalizumab and more than half of these patients had omalizumab-refractory disease. These patients experienced a similar clinical benefit as the overall treated population within their individual dosing groups consistent with the barzolvolimab mechanism of action. Barzolvolimab was well tolerated with a favorable safety profile.