A Phase III, Multicenter, Randomized, Double-blind, Placebo-controlled Safety Study of Xolair (Omalizumab) in Patients With Chronic Idiopathic Urticaria (CIU) Who Remain Symptomatic Despite Treatment With H1 Antihistamines, H2 Blockers, and/or Leukotriene Receptor Antagonists

The study is a global Phase III, multicenter, randomized, double-blind, placebo controlled, parallel-group study to evaluate the safety and efficacy of omalizumab administered subcutaneously as an add-on therapy for the treatment of adolescent and adult patients aged 12-75 who have been diagnosed with chronic idiopathic urticaria (CIU) who remain symptomatic despite standard-dosed H1 antihistamine treatment (including doses up to 4 times above the approved dose level), H2 blockers, and/or leukotriene receptor antagonists (LTRA).