Efficacy and Safety of Omalizumab Against Chronic Spontaneous Urticaria: Real-world Study from China.

Background: Omalizumab is an effective treatment for chronic spontaneous urticaria (CSU) patients aged >12 years, but its efficacy in patients aged <12 years has not been fully docu-mented. We evaluated the therapeutic efficacy and safety of omalizumab in Chinese CSU popu-lation across all age groups.Objectives: To assess the efficacy and safety of omalizumab treatment against CSU in China.Methods: This study was a retrospective and observational study, and the clinical data of CSU patients treated with omalizumab from October 2018 to August 2021 were collected and analyzed.Results: We enrolled 235 patients in this study, and 54.0% (n = 127/235) of patients were female. All patients received at least three injections of omalizumab treatment, and the mean treatment duration was 3.4 +/- 1.0 months. At the end of week-12, 98.7% (n = 232/235) of patients responded to omalizumab, among which 91.1% (n = 214/235) achieved a complete response (CR). An excellent response to omalizumab treatment was observed across all ages. All patients aged <12 years (n = 26) achieved a CR at the end of week-12, and clinical improvement was maintained until treatment cessation. Eighty-seven patients received 3-9 -month follow-up after the end of treatment, with a mean duration of 5.7 +/- 2.0 months, and 17.2% (n = 15/87) patients experienced recurrence after discontinuing treatment. No factors associated with therapeutic response and recurrence to omalizumab treatment were found in this study. Conclusion: Omalizumab is a safe and efficacious therapy for CSU patients, including those aged <12 years. We recommend addition of omalizumab to the treatment regimen in CSU patients under 12 years of age.Trial registration number: This study was registered in Chinese Clinical Trial Registry (www. chictr.org.cn, Registration number: ChiCTR2200056599).