GlaxoSmithKline has filed regulatory submissions in the US and Europe for mepolizumab, a new biologic for treating asthma. The company is seeking approval for the drug as a maintenance treatment for patients with severe eosinophilic asthma, identified by a blood eosinophil count of at least 150 cells per microliter at the start of treatment or 300 cells per microliter in the past 12 months.

The submissions are a biologics license application to the US Food and Drug Administrationas an add-on maintenance treatment for severe eosinophilic asthma in patients aged 12 years and older with a history of exacerbations and a marketing authorization application to the European Medicines Agency as an add-on treatment for severe eosinophilic asthma in adult patients with a history of exacerbations and/or dependency on systemic corticosteroids.

Regulatory filings in other countries are planned during the course of 2014 and 2015. Mepolizumab is not currently approved for use anywhere in the world.

Mepolizumab is a monoclonal antibody that is delivered in a 100-mg dose via subcutaneous injection every four weeks. It is an investigational humanized IgG₁ monoclonal antibody specific for IL-5, which binds to IL-5, stopping it from binding to its receptor on the surface of eosinophils. Inhibiting IL-5 binding in this way reduces blood, tissue, and sputum eosinophil levels. Mepolizumab is also being investigated in eosinophilic chronic obstructive pulmonary disease and eosinophilic granulomatosis with polyangiitis. 

Source: GlaxoSmithKline