Patients with chronic spontaneous urticaria (CSU) who have found little relief with existing treatments, a novel drug called Remibrutinib (LOU064) has shown fast and sustained disease control, says the study in Journal of Allergy and Clinical Immunology. Remibrutinib, an oral, highly selective Bruton's tyrosine kinase inhibitor (BTKi), is currently in phase 3 development for CSU, offering hope to those who remain symptomatic despite second-generation H1-antihistamines.


In a phase 2b extension study, patients who previously participated in the core study and still had a weekly Urticaria Activity Score (UAS7) of 16 or higher received Remibrutinib at a dose of 100 mg twice daily for 52 weeks. The primary goal was to evaluate the long-term safety and tolerability of the drug. Key efficacy measures included changes in UAS7 and the proportion of patients achieving a complete response (UAS7=0) and well-controlled disease (UAS7≤6) at week 4 and over the 52-week period.
Out of 230 patients, 194 entered the treatment phase, receiving at least one dose of Remibrutinib. The safety profile of Remibrutinib remained consistent with that observed in the core study. Most treatment-related adverse events were mild to moderate and not linked to the drug. The most common adverse events involved infections (30.9%), skin and subcutaneous issues (26.8%), and gastrointestinal problems (16.5%).
At both week 4 and 52, there was a significant reduction in UAS7 from baseline, with a mean change of -17.6±13.40 at week 4 and -21.8±10.70 at week 52. Furthermore, 28.2% of patients achieved a UAS7 of 0 at week 4, rising to 55.8% at week 52. Notably, 52.7% of patients had their disease well-controlled (UAS7≤6) at week 4, increasing to 68.0% at week 52.

The results indicate that Remibrutinib offers a consistent safety profile and fast, sustained efficacy for up to 52 weeks in CSU patients inadequately controlled with H1-antihistamines. Further research and clinical trials will be necessary to confirm these promising findings and potentially provide a breakthrough treatment option for those with chronic spontaneous urticaria.
Reference:
Jain, V., Giménez-Arnau, A., Hayama, K., Reich, A., Carr, W., Tillinghast, J., Dahale, S., Lheritier, K., Walsh, P., Zharkov, A., Hugot, S., & Haemmerle, S. (2023). Remibrutinib demonstrates favorable safety profile and sustained efficacy in chronic spontaneous urticaria over 52 weeks. In Journal of Allergy and Clinical Immunology. Elsevier BV. https://doi.org/10.1016/j.jaci.2023.10.007