Positive Phase II Barzolvolimab Data

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 a Phase II chronic spontaneous urticaria (CSU) study (52 week analysis) and a Phase II chronic inducible urticaria (CIndU) study (12 week analysis), barzolvolimab demonstrated rapid and sustained improvement in urticaria control and greatly reduced disease impact on quality of life, as measured by the Urticaria Control Test (UCT) and Dermatology Life Quality Index  (DLQI). The data were presented by Martin Metz, M.D., Deputy Director, Head of Translational Research at Charité - Universitätsmedizin Berlin in poster presentations  as part of the American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting 2025.

“Patients suffering with chronic urticaria have symptoms which severely impact their daily lives for years or even decades—often with devastating impacts on their quality of life—and treatment options are very limited,” said Martin Metz, MD, Deputy Director, Head of Translational Research at Charité - Universitätsmedizin Berlin. “Barzolvolimab has demonstrated its potential to completely change the treatment paradigm and enable patients to live normally again. We are especially excited to see these meaningful improvements consistently across patients with both CSU and CIndU in large clinical studies.”

The quality of life impairment that patients with CSU experience have been well studied and shown to impact many aspects of life including daily activities, work performance, sleep quality, social functioning and relationships, and mental health, which can manifest as depression, anxiety and suicidal ideation. A recent multi-national patient survey found that the majority of patients report a moderate to high impact from CSU on their daily life. Current clinical guidelines recommend complete disease control as the goal of treatment, and several published analyses have shown that patients have minimal or no impact on their quality of life when they are able to achieve complete disease control^,

Phase II CSU trial disease control and quality of life measurements (52 week analysis)

• i . Up to 71% of patients with CSU achieved complete response (UAS7 = 0) at Week 52
• ii.  Rapid and sustained improvement in urticaria control (UCT) and quality of life (DLQI) observed in patients with CSU refractory to antihistamines
• iii. Up to 82% of patients reported that CSU symptoms no longer had an impact on their quality of life at Week 52
• iv. Up to 95% of patients reported meaningful improvement in quality of life based on DLQI at Week 52
• v.  Up to 82% of patients reported well-controlled urticaria based on UCT, and approximately half of patients reported complete control at Week 52

Phase II CIndU trial disease control and quality of life measurements (12 week analysis)

• i.  Up to 53% of patients with ColdU and 58% of patients with SD achieved complete response (negative provocation test)
• ii. Marked and rapid improvement in urticaria control (UCT) and quality of life (DLQI) in patients with ColdU and SD; sustained through the 12-week period
• iii. Up to 60% of patients reported that CIndU symptoms no longer had an impact on their quality of life at Week 12
• v. Up to 69% of patients reported well-controlled urticaria based on UCT at Week 12

About Chronic Spontaneous Urticaria (CSU); CSU is characterized by the occurrence of hives or wheals for 6 weeks or longer without identifiable specific triggers or causes. The activation of the mast cells in the skin (release of histamines, leukotrienes, chemokines) results in episodes of itchy hives, swelling and inflammation of the skin that can go on for years or even decades. Current therapies provide symptomatic relief only in some patients.

About Chronic Inducible Urticaria (CIndU); CIndU is characterized by the occurrence of hives or wheals that have an attributable trigger associated with them. ColdU symptoms include itching, burning wheals/hives and angioedema when skin is exposed to cold temperatures. SD symptoms include the development of wheals in response to stroking, scratching or rubbing of the skin. For these diseases, mast cell activation leading to release of soluble mediators is thought to be the driving mechanism leading to the wheals and other symptoms. There are currently no approved therapies for chronic inducible urticarias other than antihistamines and patients attempt to manage symptoms associated with their disease through avoidance of triggers.