Targeted therapy for chronic respiratory disease: a new paradigm.

Targeted therapy has emerged as a highly effective treatment approach for chronic respiratory diseases. Many of these conditions have dismal outcomes; however, targeted therapy shows great results for the subgroup who respond. This represents a new way to approach these conditions and offers great promise as a future treatment direction. In severe eosinophilic asthma, therapy that targets the interleukin-5 pathway with monoclonal antibodies leads to a 50% reduction in asthma exacerbations in previously refractory disease. In cystic fibrosis, lung function improves with therapy that targets specific molecular abnormalities in the cystic fibrosis transmembrane conductance regulator to increase the probability that this chloride channel is open. In lung cancer, specifically adenocarcinoma with epidermal growth factor receptor (EGFR) mutation and overexpression of EGFR tyrosine kinase, therapy that inhibits EGFR tyrosine kinase gives better outcomes than conventional chemotherapy.