The US Food and Drug Administration approved remibrutinib (Rhapsido), for adults with chronic spontaneous urticaria who remain symptomatic despite H1-antihistamine therapy.
The oral therapy, taken twice daily, was evaluated in the phase 3 REMIX-1 (NCT05030311) and REMIX-2 (NCT05032157) randomized, placebo-controlled trials. At Week 12, remibrutinib produced statistically significant improvements from baseline versus placebo across multiple endpoints: Itch Severity Score over 7 days (ISS7), Hives Severity Score over 7 days (HSS7), and weekly Urticaria Activity Score (UAS7). More patients achieved well-controlled disease (UAS7 of 6 or less) beginning at Week 2 and continuing through Week 12 versus placebo. About one-third of patients had complete absence of itch and hives at Week 12.
“Remibrutinib represents a new way of treating CSU. By blocking the activity of BTK, remibrutinib stops a key pathway of the immune response in CSU. This is an exciting new option that has the potential to help a broad range of patients get fast relief,” said Mark Lebwohl, MD, of the Icahn School of Medicine at Mount Sinai, who served on the REMIX trial steering committee.
Remibrutinib targets BTK activation in mast cells and basophils following immune activation via allergic (IgE) or autoimmune (IgG) pathways. Once activated, BTK triggers release of histamine and other proinflammatory mediators that drive the characteristic red, swollen, itchy hives of this mast cell–driven condition.
“The approval of remibrutinib is an important development in CSU care. It quickly reduces symptoms, offering patients control of the hives and itching that they experience on a daily basis,” said Giselle Mosnaim, MD, MS, of the University of Chicago Pritzker School of Medicine and Endeavor Health, a REMIX investigator. “This is significant because it expands beyond existing injectable treatments and gives patients an oral option that can easily be incorporated into their daily lives.”
Safety: No laboratory monitoring is required. The most common adverse events, occurring in at least 3% of patients, were nasopharyngitis, bleeding, headache, nausea, and abdominal pain.
Regulatory and pipeline: Novartis has submitted applications in multiple regions, including the European Union, Japan, and China (priority review in China), and is investigating remibrutinib in chronic inducible urticaria, hidradenitis suppurativa, and food allergy.
Source: Novartis
