[Severe asthma and biological therapies]

Severe asthma is a relatively common, chronic, heterogeneous inflammatory disease affecting around 4-10% of all asthmatics. Most of these have uncontrolled eosinophilic asthma, the treatment of which accounts for >50% of healthcare costs attributed to the disease. Management of severe asthma requires a thorough investigation to exclude comorbidities and determine the underlying type of inflammation and resulting asthma phenotype, so that suitable treatments can be chosen. Systematic assessment and evaluation of treatment must then be performed every 3-6 months. Severe asthma is mostly driven by type 2 inflammation, and we now have several specific biological therapies targeting this inflammation, yet some patients remain poorly controlled due to the heterogenous nature of this disease with its many sub-phenotypes. Therefore, research must determine which clinical and patient reported outcomes as well as biomarkers best reflect response to therapy and thus should be monitored in the clinic.