Celldex Therapeutics (CLDX) H.C. Wainwright 4th Annual Inflammatory Skin Disease Virtual Conference summary

Key clinical insights and data

• Barzolvolimab, an anti-KIT monoclonal antibody, targets mast cells directly, offering a novel mechanism compared to competitors that target IgE or cytokines like IL-4/IL-13.

• Phase II studies in CSU and inducible urticaria showed rapid, profound, and durable symptom relief, with up to 70% complete response at 52 weeks and 41% off-therapy response at seven months.

• Statistically significant benefits were observed in cold urticaria and symptomatic dermographism, including improved provocation test results and quality of life.

• Durability of response is notable, with patients maintaining milder disease after stopping therapy and regaining full response upon retreatment.

• Tryptase levels, a marker of mast cell burden, normalized in patients, supporting biological disease modification.

Phase III program and endpoints

• Phase III CSU study enrolled 1,900 patients, including omalizumab-refractory cases, with two dosing regimens and a six-month placebo control.

• Primary endpoint is mean change in Urticaria Activity Score 7 (UAS7), with the study powered to detect a 10-point difference.

• High complete response rates and efficacy in bio-refractory populations are key benchmarks for success.

• Enrollment completed faster than competitors, reflecting unmet need and strong physician interest.

Commercial and market outlook

• Chronic urticaria advanced therapies market projected to reach $12 billion globally, with significant growth potential as diagnosis and treatment rates improve.

• Barzolvolimab is positioned for both first-line advanced therapy (severe, antihistamine-refractory patients) and as a preferred second-line option for those failing other advanced therapies.

• Differentiation lies in high complete response rates, deepening and durable responses, and efficacy in angioedema and bio-refractory patients.

• Off-drug durability offers unique payer and utilization advantages.