IL5 and asthma: Tezepelumab has already successfully completed phase II and III clinical trials, with results indicating a reduction in rates of asthma exacerbations, improved FEV1, and a reduction of T2 inflammatory biomarkers such as IL-5, IL-13 periostin, and IgE in both T2 high and T2 low individuals with severe asthma, and without an increase in adverse effects over those of placebo (157–162, 166).