Remibrutinib improves sleep, daily activities in patients with CSU

Treatment with remibrutinib, an oral, highly selective Bruton’s tyrosine kinase inhibitor, improved sleep and daily activities in patients with chronic spontaneous urticaria (CSU), according to two phase III REMIX-1 and -2 studies presented at AAD 2025.

“The symptoms of CSU can be debilitating and adversely affect patients’ sleep and daily activities. Reduction in disease activity has been shown to alleviate sleep and daily activity interference,” said Dr Robert Snyder from Riverchase Dermatology, Pembroke Pines, Florida, US.

The researchers conducted two identical, multicentre, phase III studies involving 470 (REMIX-1) and 455 patients (REMIX-2) with CSU. These patients were randomized 2:1 to receive either remibrutinib 25 mg twice daily (n=313 for REMIX-1 and n=300 for REMIX-2) or placebo (n=157 and n=155, respectively) for a 24-week double-blind treatment period, followed by a 28-week open-label treatment period. At week 24, all placebo recipients were switched to remibrutinib (placebo-transitioned remibrutinib arm). [AAD 2025, abstract 62278]

The weekly Sleep Interference Score (SIS7) and Activity Interference Score (AIS7) were used to determine the effect of remibrutinib on sleep and daily activities in this patient population.

In terms of sleep outcome, a higher percentage of patients treated with remibrutinib had zero sleep interference (SIS7=0) at week 24 (58.9 percent in REMIX-1 and 58.2 percent in REMIX-2 vs 44.2 percent and 41.2 percent in the two respective placebo arms).

By week 52, 60.6 percent and 64.7 percent of patients who received remibrutinib in REMIX-1 and REMIX-2, respectively, achieved an SIS7 score of zero.

“There was a rapid response in terms of differentiating the improvement in sleep deprivation between remibrutinib and placebo as early as week 1, with progressive improvement through week 24, and a high level of response of no impact [of CSU] on sleep and daily activity, which is what we strived for with treatment, that was maintained through week 52,” said Snyder.

In terms of daily activities, more than half of the participants in the remibrutinib group achieved a complete absence of activity interference or no impact of CSU on daily activities (AIS7=0) at week 24 relative to the placebo group in both studies (REMIX-1: 55.8 percent vs 42.1 percent and REMIX-2: 53.4 percent vs 32.8 percent).

Patients who transitioned to remibrutinib from placebo and those who received remibrutinib initially had similar improvements in terms of achieving AIS7=0 at week 52 (57 percent vs 62.5 percent [REMIX-1] and 62.8 percent vs 60.7 percent [REMIX-2]).

“In both REMIX studies, remibrutinib treatment led to a complete absence of sleep and daily activity interference in a greater proportion of patients at week 24. These effects were maintained through week 52,” said Snyder.

“Remibrutinib has the potential to become an effective oral treatment option for patients with CSU that may improve aspects of their well-being such as sleep and daily activities,” he added.