Impact statement for respiratory
We have demonstrated that eosinophilic airway inflammation is a readily identifiable and important treatable aspect in patients with severe asthma and COPD and that specific inhibition of this process with mepolizumab (anti-IL-5) is associated with important clinical benefits in patients with this pattern of airway inflammation. Mepolizumab has recently been approved for use in severe eosinophilic asthma, the first entirely new class of treatment for 20 years. This work has been the catalyst for the successful clinical development of six other biological agents targeting eosinophilic inflammation in airways disease; it has led to a new paradigm for the assessment and treatment of airways disease where treatment is directed against biomarkers of eosinophilic inflammation rather than unrelated measures of symptoms and lung function. An important example has been our recognition of the peripheral blood eosinophil count as a biomarker of the long-term response to inhaled corticosteroid treatment in patients with COPD. Use of this biomarker has resulted in better targeting of one of the most costly treatments used in primary care and the development of clear criteria for the use of dual bronchodilator therapy. It is now recommended by guideline groups.