Longitudinal Phenotyping and Endotyping Study in Adult Patients With Mild, Moderate, or Severe Asthma

Inclusion Criteria: 1. Male or Female patients aged ≥ 18 years and older who have signed an Informed Consent form. 2. All patients who attend the hVIVO respiratory site clinics who have a clinical diagnosis of asthma/any of the following: * Positive response to methacholine challenge test (AHR), or * Positive response to a bronchodilator responsiveness test, or * Peak Flow variability (i.e. highest - lowest PEF over the day/mean value of the two, × 100) \> 20%, or * Documented response (defined as ΔFEV1 ≥ 12% and ≥ 200 mL) after a cycle (e.g., 4 weeks) of regular maintenance anti-asthma treatment, or * physician diagnosis of current asthma. 3. In the PI/investigator(s) opinion, will be able to follow the study requirements. Exclusion Criteria: 1. Asthma patients who are not attending hVIVO respiratory site clinics. 2. Patients whose primary respiratory diagnosis (i.e. the condition causing most of their respiratory symptoms) is not asthma (however, a co-diagnosis of another respiratory disease such as COPD, bronchiectasis or interstitial lung disease together with asthma will be accepted) 3. Females who: 1. Are breastfeeding, or 2. Have a positive pregnancy test at any point during screening 4. Patients who, in the opinion of the physician, are unlikely to complete the 5 years of follow-up, e.g. poor literacy, substance abuse, life threatening comorbidities. 5. Contraindications for lung function testing, e.g., hemoptysis of unknown origin, history of pulmonary hypertension, previous pneumothorax, unstable cardiovascular status (severe heart failure, or ischemic heart disease), aneurysms (thoracic, abdominal or cerebral), recent eye surgery (e.g., cataract), recent thoracic or abdominal surgery. 6. Patients with lifetime history of anaphylaxis and/or a lifetime history of severe allergic reaction