Heterogeneity of response to asthma controller therapy: clinical implications

Purpose of review Patients with asthma exhibit heterogeneous responses to all classes of asthma medication. This review examines clinical characteristics, biomarkers of inflammation, and genetic Polymorphisms associated with treatment responsiveness in studies of adults and children with asthma, with an emphasis on inhaled corticosteroids and leukotriene modifiers. Recent findings Recent clinical studies extended previous observations of associations between biomarkers of allergic inflammation and responsiveness to inhaled corticosteroids, and between cigarette smoke exposure and responsiveness to montelukast. Pharmacogenetic studies revealed associations between treatment response and genetic variations in CRHR1, as well as a number of genes encoding proteins involved in the absorption, production, and action of the cysteinyl leukotrienes. Very few studies have attempted to test the ability of these phenotypic and genotypic associations to predict treatment responsiveness. Summary Additional prospective studies of sufficient size, quality, and ethnic diversity are needed to determine how best to incorporate information about genetic variations, clinical characteristics, and biomarkers into decisions about asthma therapy for individual patients.