A monoclonal antibody that blocks IgE (omalizumab) is now used in the treatment of selected patients with severe asthma. It is expensive, so patients must be selected carefully for a trial of therapy.
More potent anti-IgE antibodies that may have a broader spectrum of effects are in development.
Allergens bind to a low-affinity IgE receptor (FcεRII, CD23) as well as the high-affinity receptor FcεRI on several immune cells, including T- and B-lymphocytes. An anti-CD23 antibody (lumiliximab) is well tolerated and reduces IgE concentrations in patients with mild asthma, but its clinical efficacy has not been reported.