The role of IgE in allergen-induced inflammation and the potential for intervention with a humanized monoclonal anti-IgE antibody.

IgE plays a key role in allergic reactions, particularly the early phase response. A humanized monoclonal anti-IgE antibody (omalizumab) that prevents IgE from binding to receptors on mast cells and basophils is undergoing clinical trials in a number of allergic diseases. Following intravenous or subcutaneous administration in humans, omalizumab has a long plasma elimination half-life (1± 4 weeks) and decreases free IgE levels in serum. Omalizumab is well tolerated and shows promise in the treatment of asthma and seasonal allergic rhinitis.