Remibrutinib Improves Chronic Spontaneous Urticaria in Patients Irrespective of Previous Anti-IgE Treatment: Results From a Phase 2b Study

To explore the effect of remibrutinib (LOU064), a novel oral Bruton's Tyrosine Kinase inhibitor, in chronic spontaneous urticaria (CSU) patients with or without previous anti-IgE treatment for CSU. In this Phase 2b study (NCT03926611), 311 CSU patients were equally randomized to receive remibrutinib 10 mg once daily (qd) / 35 mg qd / 100 mg qd / 10 mg twice daily (bid) / 25 mg bid / 100 mg bid or placebo for 12 weeks. Outcomes included change in weekly Urticaria Activity Score (UAS7) from baseline and rate of patients achieving UAS7=0 and UAS7≤6 at Week 12, with or without previous anti-IgE treatment. At baseline, 27% (84/311) of patients had a history of previous anti-IgE treatment. At Week 12, no consistent difference in UAS7 change from baseline was observed between subgroups with or without previous anti-IgE treatment: remibrutinib 10 mg qd: −21.1 and −20.6; remibrutinib 35 mg qd: −25.2 and −19.0; remibrutinib 100 mg qd: −7.7 and −18.8; remibrutinib 10 mg bid: −14.8 and −20.5; remibrutinib 25 mg bid: −25.8 and −18.7; and remibrutinib 100 mg bid: −26.2 and −18.1; and placebo: −2.8 and −9.7. Similarly, no different trends were observed in subgroups with and without previous anti-IgE treatment in terms of proportion of patients achieving UAS7=0 and UAS7≤6, across remibrutinib doses and placebo, at Week 12. Remibrutinib (all doses) showed improvement in UAS7 and achievement of UAS7=0 and UAS7≤6 irrespective of previous anti-IgE treatment. Larger studies are required to confirm the findings of this Phase 2b study.