Novartis Phase III Data Shows Long-Term Efficacy and Safety of Oral Remibrutinib in Chronic Urticaria

A recent study by Novartis has unveiled promising data regarding the long-term efficacy and safety of remibrutinib, a Bruton’s tyrosine kinase (BTK) inhibitor, for treating chronic spontaneous urticaria (CSU). This condition, characterized by persistent, itchy hives and swelling, affects individuals who do not respond adequately to second-generation H1-antihistamines. The findings from the Phase III REMIX-1 and REMIX-2 studies were presented at the 2024 European Academy of Allergy and Clinical Immunology Congress in Valencia, Spain.

Remibrutinib has demonstrated rapid and sustained symptom relief in patients with CSU. Improvements in weekly urticaria activity scores (UAS7) were noticeable as early as week one and maintained for up to 52 weeks. The data highlighted significant reductions in itch severity (ISS7) and hive severity (HSS7) scores compared to placebo, confirming the drug's efficacy observed at week 12 and extending it to week 24. At this point, patients on placebo switched to remibrutinib and experienced similar rapid and sustained symptom relief through the end of the study period.

Professor Martin Metz of Charité – Universitätsmedizin Berlin emphasized the importance of this treatment, noting that many CSU patients fail to find lasting relief with high doses of antihistamines, severely impacting their daily lives. Remibrutinib works by blocking the BTK pathway, thereby inhibiting histamine release, which is responsible for the symptoms of CSU.

The study also reported that almost half of the patients treated with remibrutinib were completely free of itch and hives by week 52. The safety profile of the drug was favorable and consistent throughout the treatment duration, with balanced liver function tests and comparable adverse event (AE) rates between the remibrutinib and placebo groups. Serious AEs and treatment discontinuations due to AEs were comparable, with no increase in exposure-adjusted rates over the long term. Liver transaminase elevations were noted to be asymptomatic, transient, and reversible.

Tonya Winders, President and CEO of the Global Allergy and Airways Patient Platform, highlighted the distressing nature of CSU due to its unpredictability and the debilitating symptoms that affect various body parts. She welcomed the advancement in research that remibrutinib represents, offering hope for effective management of CSU symptoms.

Additionally, Novartis plans to submit remibrutinib for regulatory approval in CSU starting in the second half of 2024. The company is also exploring the drug's potential in treating other immune-mediated conditions, including hidradenitis suppurativa, food allergies, chronic inducible urticaria, and multiple sclerosis. In a Phase II study, remibrutinib met its primary endpoint for hidradenitis suppurativa, showing its potential across various conditions.

Remibrutinib represents a significant advancement in the treatment of CSU, offering a well-tolerated, effective oral therapy option. It complements the existing Novartis immunology portfolio, which includes Xolair® (omalizumab), the first injectable biologic for CSU. The REMIX-1 and REMIX-2 studies confirm remibrutinib's efficacy and safety, establishing it as a promising first-in-class treatment option for patients with CSU inadequately controlled by antihistamines.

In conclusion, remibrutinib has the potential to transform the management of CSU and other immune-mediated conditions, providing patients with a new and effective treatment option. The upcoming regulatory submissions and ongoing research in various indications underscore Novartis's commitment to addressing unmet clinical needs in immunology.