DETACT sEvere asThmAtiC paTients - a Pilot Study

Inclusion Criteria: All patients who: * are ≥18 years of age * have a recorded clinical diagnosis of asthma (ICD-10 Code: J45) * meet the requirements for treatment of severe T2-high asthma for Dupilumab defined as: * FeNO \> 25 ppB * two measurements of at least 250 eosinophils /µl in the blood OR one measurement of blood eosinophils at least 250 cells/µl during reduction of OCS dosing if treated with oral corticosteroids and/or one measurement of sputum ≥ 2% or BAL eosinophils ≥ 1% * have a history of treatment with monoclonal antibodies for asthma if a wash out period of 2 half-lives or 1 month (whatever is longer) has passed Exclusion Criteria: Patients who: * are pregnant as determined by a ß-HCG test * have severe anatomic variations or deviations that do not allow bronchoscopy * suffer from additional others confounding underlying lung disorder including but not limited to: Bronchiectasis, chronic obstructive pulmonary disorder (COPD), pulmonary fibrosis, emphysema, Cystic fibrosis, any known parasitic infections and lung cancer. * show pulmonary conditions with symptoms of asthma and blood eosinophilia, including but not limited to: Churg-Strauss syndrome, allergic bronchopulmonary aspergillosis, hypereosinophilic syndrome * suffer from a mental condition rendering the subject unable to understand the nature, scope and possible consequences of the study, * have clinically meaningful comorbidity as determined by the evaluating committee, * experience of an asthma exacerbation within 4 weeks prior to the first main visit * immune disorder and/or immunosuppressive treatment (e.g. cyclosporine), ongoing biological treatment of asthma (e.g., mepolizumab, omalizumab, benralizumab) or last biological treatment 2 half-lives or 1 month before the first main visit * have a history of drug and alcohol abuses * are currently smoking or are former smokers for less than 6 months with \>10 pack years