Learning objectives: To familiarize the practitioner with a novel (monoclonal anti-immunoglobulin [Ig]E antibody) form of therapy for allergic airways disease. To understand the relevance of IgE as a therapeutic target. To appreciate the concepts behind the design of the molecule. To learn how anti-IgE was used in clinical trials. To anticipate the likely effects (efficacy and safety) in clinical use in patients with allergic asthma and with allergic rhinitis. To characterize the types of patients who might benefit from this therapy.
Data sources: Published data for preclinical and clinical studies.
Results: Omalizumab is a nonimmunogenic, nonanaphylactogenic monoclonal anti-IgE antibody. In clinical use, omalizumab reduces levels of serum-free IgE. Given subcutaneously in patients with moderate-severe allergic asthma, omalizumab reduced exacerbations compared with placebo, and at the same time it allowed inhaled corticosteroids to be reduced or withdrawn. In patients with allergic rhinitis, omalizumab reduced the severity of symptoms and rescue antihistamine usage versus placebo. In both settings, quality of life was improved with active treatment relative to placebo. The drug seems safe and well tolerated.
Conclusion: As the first clinical anti-IgE agent, omalizumab is an interesting new addition to the currently available therapies for allergic airways disease. The benefits demonstrated underline the importance of IgE in these conditions. The use of anti-IgE in other IgE-mediated allergic diseases warrants further research.