Barzolvolimab Demonstrates Long-Term Efficacy for Chronic Urticaria

Barzolvolimab, a novel treatment for chronic spontaneous urticaria (CSU), has shown sustained efficacy and significant improvements in patient quality of life (QoL) over a period of up to 76 weeks post-treatment, according to recent findings presented at the European Academy of Allergy and Clinical Immunology Congress 2025. This persistent therapeutic response highlights barzolvolimab's potential as a transformative treatment option for patients suffering from this debilitating condition.

Chronic spontaneous urticaria is characterized by unpredictable, itchy hives or angioedema lasting longer than six weeks, affecting over 80% of patients for more than a year. Approximately 40% of CSU patients report significant reductions in their quality of life due to this condition (Santoro, 2025). Novel therapies, including barzolvolimab, have emerged as promising solutions, particularly for those patients who are refractory to conventional treatments such as antihistamines.

The mechanism of action of barzolvolimab involves the inhibition of the receptor tyrosine kinase KIT, essential for mast cell survival and function. In prior clinical trials, including a phase 2 study, barzolvolimab demonstrated a statistically significant improvement in the Urticaria Activity Score over 7 days (UAS7) compared to placebo, particularly at 12 weeks (Celldex, 2024). The recent data revealed even deeper responses in UAS7 scores at 76 weeks, with a mean change of –20.42 for patients receiving 150 mg every four weeks and –21.10 for those on 300 mg every eight weeks.

At the 76-week mark, approximately 41% of patients in the 150 mg group and 35% in the 300 mg group achieved a complete response, defined as no itch or hives (UAS7 = 0). Furthermore, 56% of patients treated with 150 mg and 47% of those on 300 mg reported well-controlled disease status (UAS7 ≤ 6), indicating significant therapeutic benefit.

Quality of life improvements were measured using the Dermatology Life Quality Index, which evidenced that 48% of patients on the 150 mg regimen and 40% on the 300 mg regimen reported no impact from CSU on their daily lives by week 76. Such outcomes are particularly noteworthy as clinical guidelines emphasize the importance of achieving a complete response to optimize QoL in CSU patients (Metz et al., 2025).

Dr. Martin Metz, lead investigator of the study and Professor in the Department of Dermatology and Allergy at Charité Universitätsmedizin, stated, "Barzolvolimab provided meaningful clinical benefit to more than 90% of the patients on study, including those with severe disease refractory to omalizumab, and demonstrated a level of sustained complete response after the completion of active therapy that is unprecedented in CSU" (Celldex, 2025).

In terms of safety, barzolvolimab exhibited a favorable profile, with adverse events predominantly classified as grade 1, mechanism-related, and reversible. No new safety signals emerged during the follow-up period, and previously reported neutropenia events resolved rapidly without an association with increased infection rates. Patients’ neutrophil counts returned to baseline levels after treatment cessation, further supporting the drug's tolerability (Metz et al., 2025).

The implications of these findings are significant for the future of CSU treatment. As more patients are diagnosed with chronic spontaneous urticaria, the demand for effective, long-lasting treatments increases. Barzolvolimab's efficacy and safety profile positions it as a leading candidate for patients who have not responded adequately to existing therapies. The ongoing research into its long-term effects could redefine treatment protocols and improve the quality of life for countless individuals suffering from this condition.

In conclusion, the long-term efficacy of barzolvolimab in chronic spontaneous urticaria not only demonstrates its potential as a groundbreaking treatment but also underscores the importance of continued innovation in therapeutic options for this challenging condition. Future studies will be essential in fully understanding the long-term outcomes and broader applicability of this promising therapy.