Treating atopic asthma with the anti-IgE monoclonal antibody.

Omalizumab is a nonanaphylactogenic humanized murine monoclonal antibody which binds to circulating immunoglobulin (Ig)E but does not bind to IgE bound to inflammatory cells because in this case the epitope on IgE against which omalizumab is directed is already attached to cell receptors and is masked. By binding to free circulating IgE omalizumab prevents the allergic and asthmatic responses that are mediated by the interaction of IgE with high affinity and low affinity receptors on a variety of cell types. To support entry into therapy of human allergic diseases a series of safety and efficacy studies have been conducted with omalizumab in subjects affected by atopic asthma and these trials revealed that omalizumab is well tolerated, resulting in a dose-dependent decrease in serum free IgE levels. Omalizumab exhibited a prolonged pharmacological effect without inducing anaphylaxis, blunted the early- and late-phase responses to inhaled allergen, reduced the symptoms of asthma improving lung function and quality of life and reduced corticosteroid use.