Omalizumab

Omalizumab (Xolair) is a medication originally designed to reduce sensitivity to allergens and is used for treating chronic idiopathic urticaria and allergic asthma.

It is a monoclonal antibody that binds to free immunoglobulin E (IgE) in the blood and interstitial fluid and to membrane-bound form of IgE (mIgE) on the surface of mIgE-expressing B cells. It inhibits the binding of IgE to FcεRI on mast cells and basophils by binding to an antigenic epitope on IgE that overlaps with the site to which FcεRI binds. In this sense, it is a potent mast cell stabilizer.