Efficacy and Safety of Omalizumab for Chronic Spontaneous Urticaria: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Omalizumab has been proposed as a possible effective treatment of chronic spontaneous urticaria (CSU). Study Question: We aimed to access the efficacy and safety of omalizumab in the treatment of CSU based on qualified, randomized controlled trials (RCTs). Data Sources: PubMed, the Cochrane library, and Embase databases. Study Design: Computerized search by index words was performed to identify qualified RCTs, and relevant literature sources were also searched. Result: Nine RCTs were included in the meta-analysis with 1612 patients in the omalizumab group and 1251 patients in the placebo group. Compared with the placebo group, omalizumab significantly decreased the weekly itch score after therapy [Weighted Mean Difference (WMD), -3.94; 95% confidence interval (CI), -4.64 to -3.24], the weekly hive score (WMD, -5.27; 95% CI, -6.17 to -4.38), the dermatology life quality index (DLQI; WMD, -3.58; 95% CI, -4.66 to -2.50), and the urticaria activity score over 7 days (UAS7; WMD, -9.51; 95% CI, -10.94 to -8.08). There was no significant difference in the incidence of adverse events (AE) [relative risk (RR), 1.01; 95% CI, 0.91-1.12], serious AE (RR, 0.85; 95% CI, 0.57-1.27), and severe AE (RR, 0.83; 95% CI, 0.60-1.14) between the 2 groups. Compared with the placebo, omalizumab significantly decreased the weekly itch score and weekly hive score after therapy in patients receiving 75, 150, and 300 mg omalizumab, respectively. DLQI was significantly reduced in patients receiving 150 and 300 mg of omalizumab, respectively. In all the subgroup of UAS7, omalizumab significantly decreased the score compared with the placebo. Only patients receiving 600-mg omalizumab had a significantly higher AE incidence versus placebo. There was no significant difference in serious and severe AE between the 2 groups. Conclusion: Omalizumab caused a significantly greater reduction in weekly itch score, weekly hive score, DLQI, and UAS7 in CSU patients than the placebo. However, high-quality, multicenter RCTs with a larger sample size are needed to confirm the safety of omalizumab, and whether AEs are caused by omalizumab or other factors.