Omalizumab has been shown to be a very effective drug in chronic spontaneous urticaria (CSU) improving patients' quality of life.1 Phase III clinical trials ASTERIA I/II and GLACIAL showed respectively 58.8-52.4% of patients achieving a twice daily average Urticaria Activity Score 7 (UAS7td)≤6 at week 12.2 Outside of clinical trials, the response varies between 77-83%.3 However, some patients do not achieve well-controlled activity of the disease with the licensed dose of omalizumab (300mg/4 weeks). This article is protected by copyright. All rights reserved.