The first 18 months of tezepelumab in real-life practice: Characteristics of patients commenced and efficacy in a nationwide, complete cohort of patients with severe asthma

<bold>Background:</bold> Tezepelumab holds significant potential in the treatment of severe asthma owing to its upstream target in the inflammatory cascade and could be an appropriate choice of biologic for many different patient groups. <bold>Aims:</bold> In this study, we aimed to characterise the patients prescribed tezepelumab and its efficacy during the first 18 months of the drug being available in a nationwide, complete cohort of patients with severe asthma. <bold>Methods:</bold> In this prospective observational study, we used data from the Danish Severe Asthma Register (DSAR). We categorised patients according to their previous treatment as either Bionaive or Switchers and investigated effects in asthma-related outcomes after 12 months of treatment. <bold>Results:</bold> Of the 216 patients initiated on tezepelumab during its first 18 months in clinical practice, 141 (65 %) were switchers. Bionaive patients had a median blood eosinophil count of 0.20 cells x 109/L and fractional exhaled nitric oxide (FeNO) of 18 ppb. After 12 months of treatment, both bionaive patients and switchers showed significant improvements in exacerbations, maintenance oral corticosteroid use and symptoms and 79% of patients in both groups achieved a clinical response to treatment. Surprisingly, switchers experienced superior improvement in lung function. <bold>Conclusions:</bold> Most patients initiating tezepelumab during its first 18 months in clinical practice were switchers, and the bionaive patients initiated had relatively low type-2 inflammatory biomarkers, highlighting the complexity of patients on tezepelumab. However, 79 % of patients in both groups achieved a clinical response to treatment.