Since the anti-IgE therapeutic concept was conceived in 1987, the lead product, omalizumab, a humanized antibody with a unique set of binding specificities, has been studied in more than 50 Phase II and III clinical trials in various allergic indications.
　　 Omalizumab (trade name Xolair) has been approved in the USA, EU, Taiwan and many other countries for treating patients 12 years and older with severe allergic asthma. Xolair has also been approved in EU in 2009 for treating patients 6 to 11 years old with severe allergic asthma. Omalizumab has been shown to be efficacious for treating allergic rhinitis in many organized, corporate-sponsored, placebo-controlled Phase II and III trails. Xolair has been shown to be efficacious in treating atopic dermatitis and urticaria in about 10 case series studies covering over 50 patients. In several major trials, Xolair has been shown to reduce the anaphylaxis risks and enhance the efficacy of allergen-based desensitization immunotherapy. More than 100,000 patients with severe allergic asthma, whose symptoms cannot be controlled even with high doses of corticosteroids, have been treated with omalizumab. In Taiwan, Xolair was approved for treating patients 12 years and older with severe allergic asthma in 2007 and a payment policy was issued by the Health Insurance Bureau in 2008. A few hundred patients with severe allergic asthma have been treated with Xolair in major medical centers with response rates estimated to be over 80%. In Taiwan, a small number of patients with severe atopic dermatitis have also been treated with Xolair in off-label uses with generally good results.

　　In this presentation, the “Skewed Antigen Exposure Theory” for explaining the increase of allergic disease in modern societies will be introduced. In the main body of the talk, the rationale for designing the anti-IgE drug, the structural basis for the unique set of binding specificity of anti-IgE, the main pharmacological effects of the anti-IgE drug, and the clinical indications in which anti-IgE has been tried, and the combination of anti-IgE and immunotherapy as a new therapeutic approach will be discussed.