Safety and effectiveness of omalizumab for the treatment of chronic urticaria in pediatric patients

Background: Evidence on safety and effectiveness of omalizumab for treatment of chronic urticaria in pediatric patients is scarce and limited to case reports. In particular, drug survival of omalizumab has not yet been investigated, which is a key element in the evaluation of its clinical performance. The aim of this study was to investigate safety, effectiveness, and drug survival rates of omalizumab in a daily practice cohort of pediatric patients with chronic urticaria (CU). Methods: This is a multicenter study including all pediatric patients from an academic center (Wilhelmina Children's Hospital) and a general center (Diakonessenhuis Hospital) in the Netherlands, who started omalizumab treatment before the age of 18 years. Data on safety, effectiveness, time to discontinuation, and reasons for discontinuation of treatment were assessed. Drug survival of omalizumab was estimated using the Kaplan-Meier survival analysis. Results: A total of 38 patients, who started treatment between January 2014 and January 2020, were included. Most patients (68.4%) used omalizumab without reporting any side effects and a complete or good response to treatment was achieved in 76.3% of patients. The 1- and 2-year drug survival rates were 62% and 50%, respectively, with well-controlled disease activity as the most frequent reason for discontinuation in 69.2% of patients, followed by ineffectiveness in 23.1% and side effects in 7.7% of patients. Conclusions: This study demonstrates high safety and effectiveness of omalizumab treatment in pediatric patients with CU, which will aid clinical decision making and management of expectations when choosing omalizumab treatment for pediatric patients with CU.