To establish the advantages of novel asthma medicines or treatments, their impact on important clinical outcomes should be evaluated. Symptoms, rescue medicine requirements, and pulmonary function tests have been the most commonly utilized outcomes, although others such as quality of life, exacerbations, and impairment of activities have also been recognized as relevant. Improvements in our understanding of the underlying processes of asthma have resulted in the creation of new sets of outcomes, including inflammatory indicators and a fast-growing number of biomarkers, which must now be validated and evaluated for clinical use. Many studies have examined induced sputum cell differentials or FENO not only to phenotype asthma but also as therapy effectiveness indicators. Periostin is regarded as a marker of TH2-induced airway inflammation and a predictor of responsiveness to medicines such as anti-IL13 and omalizumab, however, such prediction remains poor at the individual level.

There is a need to create novel disease activity indicators with prognostic value in terms of the advantages of new therapies.