Original articleInterventionsReal-life experiences with omalizumab for the treatment of chronic urticaria

BackgroundEvidence has shown that omalizumab, a subcutaneous anti-IgE monoclonal antibody, is highly effective for the treatment of chronic urticaria.ObjectiveTo evaluate omalizumab 150 mg/month in severe, difficult-to-treat, chronic urticaria in a real-life setting.MethodsThis prospective open-label study evaluated of 150 mg of omalizumab in severe urticaria defined by a 7-day urticaria activity score (UAS-7) higher than 30, a history of oral glucocorticoid use, and by suboptimal response to previous treatments. Two subgroups of patients at different centers (Toronto and Quebec City, Canada) were included. The primary efficacy evaluation was a change in UAS-7 from baseline. A quantitative medication score assessed the use of other anti-urticarial medications.ResultsSixty-eight patients were included: 61 with chronic spontaneous urticaria, 6 with cold urticaria, and 1 with urticarial vasculitis. Patients were followed for up to 25 months. In Toronto, mean UAS-7 decreased from 32.2 at baseline to 5.7 after the last omalizumab treatment. Seventy-nine percent achieved complete remission during omalizumab therapy (UAS-7 0) and 6 (18%) showed improvement but never achieved complete remission. The most common maintenance dosing intervals were 1 to 3 months. In Quebec City, from baseline to 18 months, mean UAS-7 decreased from 24.4 to 2.2 and the quantitative medication score decreased from 13.3 to 3.0. All 6 patients with cold urticaria became symptom free, with a significant decrease of their cold stimulation tolerance test.ConclusionOmalizumab 150 mg was effective in difficult to treat patients with severe, chronic urticaria refractory to recommended treatments who usually required prednisone. Omalizumab induced a long-lasting positive response and was well tolerated without side effects.