Mepolizumab

Mepolizumab (trade name Nucala) is a humanized monoclonal antibody used for the treatment of severe eosinophilic asthma. It recognizes and blocks interleukin-5 (IL-5), a signalling protein of the immune system. Mepolizumab (trade name Nucala) is a humanized monoclonal antibody used for the treatment of severe eosinophilic asthma. It recognizes and blocks interleukin-5 (IL-5), a signalling protein of the immune system. Mepolizumab is approved by the U.S. Food and Drug Administration (FDA) for the maintenance treatment of severe asthma in patients aged 12 years or older and with an eosinophilic phenotype in combination with other medicines used to treat asthma.In Europe it is approved as an add-on treatment for severe refractory eosinophilic asthma in adult patients. In studies, mepolizumab cut the necessity for hospitalisation due to asthma exacerbations in half, as compared to placebo. In December of 2017 the U.S. Food and Drug Administration expanded mepolizumab's use to treat adult patients with eosinophilic granulomatosis with polyangiitis (EGPA), which is a rare autoimmune condition that can cause vasculitis. Common side effects in clinical trials included headache (19% of patients under mepolizumab treatment versus 18% under placebo), reactions at the site of injection (8% versus 3%), infections of the urinary tract (3% versus 2%) and the lower respiratory tract, eczema and muscle spasms (both 3% versus <1%). Single doses of 15 times the usual therapeutic dose have been tolerated in studies without significant side effects. No interaction studies have been conducted. As with other monoclonal antibodies, the interaction potential is considered to be low. Mepolizumab binds to IL-5 and prevents it from binding to its receptor, more specifically the interleukin 5 receptor alpha subunit, on the surface of eosinophil white blood cells. While eosinophils play a role in inflammation associated with asthma, the exact mechanism of mepolizumab is unknown. After subcutaneous injection, mepolizumab has an estimated bioavailability of 80% and reaches highest blood plasma concentrations after four to eight days. Like other antibodies, it is degraded by proteolytic enzymes. Its biological half-life is 20 days on average, ranging from 16 to 22 days in different individuals.