Remibrutinib demonstrates favorable safety profile and sustained efficacy in chronic spontaneous urticaria over 52 weeks

Remibrutinib (LOU064), an oral, highly selective Bruton tyrosine kinase inhibitor, offers fast disease control in patients with chronic spontaneous urticaria (CSU) who remain symptomatic despite treatment with second-generation H1 antihistamines. It is currently in phase 3 development for CSU.We sought to evaluate long-term safety and efficacy of remibrutinib in patients with CSU inadequately controlled with H1 antihistamines.In this phase 2b extension study, patients who completed the core study and had a weekly Urticaria Activity Score (UAS7) ≥16 at the beginning of the extension study received remibrutinib 100 mg twice daily for 52 weeks. The primary objective was to assess long-term safety and tolerability. Key efficacy end points included change from baseline in UAS7 and proportion of patients with complete response to treatment (UAS7 = 0) and well-controlled disease (UAS7 ≤6) at week 4 and over 52 weeks.Overall, 84.3% (194/230) of patients entered the treatment period and received ≥1 doses of remibrutinib. The overall safety profile of remibrutinib was comparable between the extension and core studies. Most treatment-emergent adverse events were mild to moderate and considered unrelated to remibrutinib by investigators. The 3 most common treatment-emergent adverse events by system organ class were infections (30.9%), skin and subcutaneous tissue (26.8%), and gastrointestinal disorders (16.5%). At week 4 and 52, mean ± SD change from baseline in UAS7 was -17.6 ± 13.40 and -21.8 ± 10.70; UAS7 = 0 (as observed) was achieved in 28.2% and 55.8% and UAS7 ≤6 (as observed) was achieved in 52.7% and 68.0% of patients, respectively.Remibrutinib demonstrated a consistent favorable safety profile with fast and sustained efficacy for up to 52 weeks in patients with CSU.