Xolair is the first humanized monoclonal antibody for the treatment of moderate to severe persistent allergic asthma and the first approved therapy designed to target the antibody IgE, a key underlying cause of the symptoms of allergy related asthma. Asthma is a chronic inflammatory airway disease caused by a reversible narrowing of the airways due to external stimuli. Xolair is indicated for adults and adolescents (12 years of age and above) with moderate to severe persistent asthma who have a positive skin test or in vitro reactivity to a perennial aeroallergen and whose symptoms are inadequately controlled with inhaled corticosteroids. Xolair is marketed in the United States by Genentech and in the rest of the world by Novartis.
How Xolair Works
Xolair binds to the Cepsilon3 domain of IgE. In some patients, when allergens enter the body, IgE antibodies are produced and circulate in the blood. IgE circulating in the blood binds to mast cells, which contain inflammatory chemicals (histamine, leukotrienes, others). Upon re-exposure to an allergen, IgE on the mast cell cross-links and triggers mast cells to release these chemicals. This chemical release triggers the inflammation, bronchial constriction and coughing associated with allergic asthma. Xolair is designed to bind to the circulating IgE antibodies in the blood, decreasing the amount of IgE antibodies available to bind to mast cells.
Xolair was approved for adult moderate-to-severe persistent allergic asthma in July 2003 in the US and in July 2005 in the EU.