Efficacy and safety of omalizumab in Japanese and Korean patients with refractory chronic spontaneous urticaria

Background Many patients with chronic spontaneous/idiopathic urticaria (CSU/CIU) do not respond adequately to treatment with non-sedating H1 antihistamines (H1AH). There are limited studies on use of omalizumab as add-on therapy for treatment of CSU in an Asian population. Objective The POLARIS study (NCT02329223), representing the first randomized, double-blind, placebo-controlled phase III trial of omalizumab for CSU in an Eastern Asian population, evaluated efficacy and safety of omalizumab as add-on therapy for treatment of CSU. Methods This 26-week multicenter (41 Japanese/Korean sites) study enrolled patients (12–75 years) who were symptomatic despite H1AH treatment. Eligible participants (N = 218) were randomized 1:1:1 to receive three subcutaneous injections of omalizumab 300 mg, 150 mg, or placebo every 4 weeks, followed by 12 weeks of follow-up. Primary outcome was change from baseline to Week 12 (Wk12) in weekly itch severity score (ISS7). Safety was assessed through the summary of adverse events (AEs). Results Baseline demographics and disease characteristics were generally well balanced across treatment groups. At Wk12, statistically significant decreases from baseline were observed in ISS7 with omalizumab vs placebo (mean changes −10.22, −8.80, and −6.51 for omalizumab 300 mg, 150 mg and placebo; p < 0.001 and p = 0.006 vs placebo, respectively). Overall AE incidence was similar across treatment groups (54.8%, 57.7%, and 55.4% in omalizumab 300 mg, 150 mg, and placebo groups, respectively); nasopharyngitis was the most frequently reported AE in all treatment arms. Conclusion The POLARIS study demonstrates that omalizumab is an efficacious and well-tolerated add-on therapy in Japanese and Korean H1AH-refractory patients with CSU.