Remibrutinib, a highly selective, oral Bruton's tyrosine kinase inhibitor, showed a favourable safety profile and sustained efficacy in patients with chronic spontaneous urticaria (CSU) in REMIX-1/-2 phase 3 studies.

We report weekly Angioedema Activity Score (AAS7) response data from pooled REMIX-1/-2 studies.

REMIX-1/-2 are identical, double-blind, placebo-controlled phase 3 studies of remibrutinib in patients with CSU remaining symptomatic despite treatment with second-generation H1-antihistamines. Patients were randomised 2:1 to add-on oral remibrutinib 25 mg bid or placebo for 24 weeks, followed by open-label remibrutinib 25 mg bid for 28 weeks for all patients. All received background second-generation H1-AH medication. This analysis evaluated AAS7 response in patients with AAS7 score > 0 at baseline (BL).

At BL, 374/606 patients in the remibrutinib arm and 169/306 in placebo arm reported angioedema, with mean BL AAS7 of 43.3 and 39.1, respectively. Among these patients, a higher proportion in the remibrutinib arm achieved AAS7 = 0 (no angioedema) response vs placebo as early as week 1 (38.9% vs 20.2%). After transitioning placebo patients to remibrutinib at week 24, the proportion of patients with AAS7 = 0 increased as early as week 25, and the effect was sustained up to week 52, with 82.4% achieving AAS7 = 0 in both remibrutinib arm and placebo-remibrutinib transitioned patients. Mean change from BL (CFB) AAS7 also improved more with remibrutinib vs placebo at all time points up to week 24; at week 24, mean CFB in AAS7 was −36.4 for remibrutinib vs −24.2 for placebo; at week 52, mean CFB was −34.9 for remibrutinib and −32.5 for placebo-remibrutinib transitioned patients. Remibrutinib also showed greater reduction in weekly UAS7 vs placebo, as early as week 1 (−13.1 vs −3.4), and was sustained up to week 52 (−24.3 for remibrutinib and −24.4 in placebo-remibrutinib transitioned patients).

In patients with angioedema at BL, remibrutinib showed fast improvements in angioedema activity, achieving higher AAS7 = 0 response rates vs placebo as early as week 1, with effects sustained up to week 52 in 82% of patients.