El omalizumab para la urticaria crónica espontánea - segunda línea

Omalizumab (Xolair) is intended to be used as second line therapy for the treatment of chronic spontaneous urticaria (CSU) that is refractory to H1 antihistamines. If licensed, it would provide an alternative treatment option beyond antihistamines, the only licensed treatment for CSU. Omalizumab is a recombinant, human monoclonal antibody that selectively binds to human immunoglobulin E (IgE) preventing binding to high affinity receptors on the surface of mast cells and basophils, thus reducing receptor expression and the release of inflammatory mediators. It is currently licensed as add-on therapy to improve asthma control in patients with severe, persistent allergic asthma who have a positive skin test or in vitro reactivity to a perennial aeroallergen. In the UK, approximately 15% of people experience urticaria at some time in their lives, with a chronic urticaria point prevalence of 1-5 per 1,000. CSU symptoms may be short-lived, resolving completely after a few months; however symptoms can persist for more than 10 years. Patients with chronic urticaria often have a severely impaired quality of life, with negative effects on sleep, daily activities, school or work life, and social interactions. Treatment options for CSU refractory to antihistamines include leukotriene receptor antagonists (i.e. montelukast, zafirlukast), dapsone and immunomodulatory medication (i.e. cyclosporin A, sulfasalazine, hydroxychloroquine, methotrexate, azathioprine, mycophenolate mofetil intravenous immunoglobulin, corticosteroids). Omalizumab is currently in phase III clinical trials comparing its effect on weekly itch scores against treatment with placebo. The trials are expected to complete in June 2013.