Bronchial asthma is a chronic inflammatory disease of the airways which is recognized as a highly prevalent health problem in both the developed and the developing world, with significant human and economic consequences.Allergy is acknowledged as a major risk factor for asthma. The pathogenetic aspects of allergic asthma are characterized by airway inflammation with infiltration of mast cells, basophils, eosinophils, monocytes and T helper type 2 lymphocytes, along with the isotype switching of B cells to generate immunoglobulins of the immunoglobulin E (IgE) class. Increased asthma severity is not only associated with recurrent hospitalization and increased mortality but also with higher social costs.Inhaled corticosteroids are the standard anti-inflammatory medication and are effective for most asthma patients, but there is a substantial number of asthmatics who remain symptomatic even after receiving treatment with inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists (beta(2)-agonists), and sometimes are in need of systemic corticosteroids to control the disease. These patients account for about 50% of the healthcare costs of asthma.New treatment options more specifically targeting the pathophysiologic events causing development of asthma are therefore required in these patients.A novel therapeutic approach to asthma and other allergic respiratory diseases involves interference with the action of IgE and prevention of subsequent IgE-mediated responses.Omalizumab is a humanized recombinant monoclonal anti-IgE antibody developed for the treatment of allergic diseases, with clear efficacy in adolescent and adult patients with moderate-to-severe allergic asthma. This non-anaphylactogenic anti-IgE antibody inhibits IgE functions by blocking free serum IgE and inhibiting their binding to cellular receptors. Omalizumab therapy is well tolerated and significantly improves symptoms and disease control, and reduces asthma exacerbations and the need to use high dosages of inhaled corticosteroids. Moreover, omalizumab improves quality of life of patients with severe persistent allergic asthma that is inadequately controlled by currently available asthma medications. In conclusion, omalizumab may fulfill an important need in patients with moderate-to-severe asthma inadequately controlled with inhaled corticosteroids +beta(2)-agonists.