Targeted biologic therapy for asthma.

BackgroundAsthma is a common and potentially serious condition affecting 300 million people worldwide. For many years, we have relied on a one-size-fits-all approach to its management, using corticosteroids and bronchodilators for all symptomatic patients. However, with more recent advances, it has become clear that asthma is a heterogeneous condition with multiple different underlying pathways. Understanding the different subtypes will be a key to giving us the ability to intervene in a targeted way to personalize care for patients with asthma.Sources of dataKey published literature, guidelines and trials from clinicaltrials.gov.Areas of agreementThe most widely studied of these subtypes is T2 high eosinophilic asthma, for which there are an increasing number of biologic therapies available. T2 high asthma is associated with the cytokines interleukin (IL)-4, IL-5 and IL-13, for each of which biologics have been developed.Areas of controversyIt is currently unclear which of the available biologics provides superior efficacy. It is also unclear how to select which biologic for which patient.Growing pointsHead-to-head trials of the available T2 biologics will be important to determine superiority, and a suggested order for trialling biologics. Going further than this, we would like to see further analyses of available biologics to allow us to predict responders from non-responders in advance of administering therapy.Areas timely for developing researchNon-eosinophilic T2 low asthma is an area that is under-researched and for which there are few treatments available. It is likely that there are different subtypes in this category of asthma and unravelling what these are will be crucial to developing effective treatments.