Remibrutinib Shows Promise for Chronic Spontaneous Urticaria in Phase 3 Trials

Remibrutinib, an investigational, highly selective Bruton tyrosine kinase (BTK) inhibitor, showed promising results in the treatment of chronic spontaneous urticaria (CSU) in the phase 3 REMIX-1 and REMIX-2 studies, according to a press release from Novartis. The findings were presented as a late-breaking abstract at the 2023 American College of Allergy, Asthma & Immunology annual meeting.

CSU, which is characterized by chronic hives that last 6 weeks or longer, is typically due to underlying internal causes and is treated with antihistamines. In patients whose disease does not respond to antihistamines, even at high doses, injectable biologic therapies can be effective—but data suggest that most patients who are eligible do not receive them.

Urticaria symptoms | Image credit: suriya - stock.adobe.com

In the REMIX-1 and REMIX-2 studies, remibrutinib met all primary and secondary end points and showed superiority compared with a placebo at week 12. Patients treated with remibrutinib experienced favorable outcomes regarding weekly urticaria activity based on the Urticaria Activity Score 7 (UAS7), itch based on the Itch Severity Score 7, and hives based on the Hives Severity Score 7.

“These findings could be significant for the millions of people who suffer from CSU and are still symptomatic,” Marcus Maurer, MD, professor of dermatology and allergy and executive director of the Institute of Allergology at Charité – Universitätsmedizin in Berlin and codirector of allergy and immunology at the Fraunhofer Institute for Translational Medicine and Pharmacology, said in a statement. “Living with CSU can be very distressing, often impacting many aspects of people’s lives such as sleep and ability to work. Having another option that could potentially provide effective relief as early as 2 weeks after trying antihistamines alone could be transformative for these patients.”

Well-controlled disease, defined as a UAS7 scored of 6 or lower, was seen in significantly more patients treated with remibrutinib. Disease control occurred as early as week 2 and was persistent through week 12. About one-third of the remibrutinib cohort experienced a complete absence of itch and hives by week 12.

Regarding safety, pooled analyses of the studies showed a well-tolerated, favorable safety profile. The rate of adverse events (AEs) with remibrutinib was similar to the placebo group (64.0% and 64.7%, respectively). Infections occurred in 32.8% of the remibrutinib cohort vs 34.0% in the placebo cohort. Liver function test abnormalities were also comparable, and liver transaminase elevations were similar across groups, and they were asymptomatic and reversible.

Patients in the REMIX-1 and REMIX-2 trials will be followed through week 52 of treatment and will be given the option to continue in an extension trial.

“Patients with CSU have limited treatment options and many patients do not respond to antihistamines even at higher than approved doses, leaving them with uncontrolled symptoms and potential side effects such as drowsiness,” Angelika Jahreis, MD, PhD, FAAD, global head of development in immunology at Novartis, said in a statement. “We are committed to developing new therapies for patients with immuno-dermatologic disorders and are excited about the prospect to provide a potential new option for patients with CSU who suffer from relentless itch and a life filled with limitations. These data show that remibrutinib, an oral BTK [inhibitor], provided significant symptom improvement as early as week 2 and sustained up to week 12.”

Reference

Novartis data show potential of remibrutinib as an oral treatment for chronic spontaneous urticaria providing significant symptom improvement as early as Week 2. News release. Novartis. November 9, 2023. Accessed November 15, 2023. https://www.novartis.com/news/media-releases/novartis-data-show-potential-remibrutinib-oral-treatment-chronic-spontaneous-urticaria-providing-significant-symptom-improvement-early-week-2