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 300mg, 150mg, 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 300mg, 150mg 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 300mg, 150mg, 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.