What is omalizumab and how does it work?
Omalizumab is an antibody that attacks a patient’s circulating IgE antibody, the antibody that is elevated in many patients with asthma, and which is partly responsible for the initial phase of the allergic response leading to swelling of the airways and wheeze. By binding IgE, omalizumab prevents IgE from attaching to cells that, when they encounter allergens, release substances (including histamine) which recruit other cells, causing more inflammation in the windpipes. Since asthma symptoms are caused by different factors that contribute to inflammation in the airways, omalizumab only treats a part of the inflammation in asthma, so is not a ‘magic bullet’. Nevertheless, it is a novel approach to treating asthma since no other medication ‘attacks’ this mechanism in asthma. Who should be considered for omalizumab? Typically, omalizumab is considered for patients who have documented allergies to specific allergens in the environment, (such as tree pollens or house dust mites), since the
