Background and study aims: The purpose of this research registry is to understand how asthma varies from person to person and monitor changes that may occur over time. The effects that asthma has on the body will be assessed, by looking at different causes/triggers of flare-ups/exacerbations, asthma symptoms, and how inflammation of the airways may affect respiratory health over time. The information obtained from this study will allow hVIVO to better understand respiratory disease progression and outcomes in asthma patients. Who can participate: Male or Female patients aged ≥ 18 years who are attending the hVIVO respiratory site clinics and have a clinical diagnosis of asthma. What does the study involve: The study will consist of a baseline clinic visit to confirm suitability and assess participants' asthma followed by approximately 5 annual clinic visits and follow-up phone calls, as necessary. Intermediate home self-assessments will also be scheduled for halfway between each annual clinic visit. Upon experiencing cold-like symptoms, participants will be asked to complete a at home self-nasal and throat swab as well as symptom, medication, and lung function home diary cards. What are the possible benefits and risks of participating: Taking part will not improve participants' health, although participants might benefit from a general health check at Screening as well as additional health checks and assessments of participants' inhaler technique during the conduct of the study. There may be unexpected and unforeseen risks related to the study procedures. When attending for clinic visits, assessment will be performed by appropriately trained and qualified staff. Participants will be monitored for any procedure related symptoms such as, pain or bruising at the site where blood is drawn. Discomfort, sneezing, watery eyes, irritated nose, or nose bleeding during nasal sample collection. Light-headedness, dizziness, fatigue, coughing, shortness of breath, headaches, chest discomfort, throat irritation and itching during lung function testing. Skin irritation and allergic reactions from skin prick testing. Should participants experience any of these symptoms, trained staff will be on hand to provide the appropriate medical treatment. The Methacholine bronchial challenge test is also likely to cause asthma symptoms such as wheezing, shortness of breath, and chest tightness. In rare cases, the test can cause severe bronchospasm. After the test or if the bronchospasm is severe, the technician will give the participant medication to inhale that will open the airways. If the participant experiences any asthma exacerbation as a result of the methacholine test, the exacerbation management guidelines will be used to assess the participant and guide treatment. Only participants that are not contraindicated for a methacholine test will have this performed. For the at home assessments, participants will receive proper training on how to perform these during screening visit and as needed during each clinic follow-up visit. Any abnormalities identified during the study will be communicated to the participant, as well as to the participant's GP or a specialist if necessary. Where is the study run from: hVIVO Services Limited - UK. Please see Participating Centres listed above for address. When is the study starting and how long is it expected to run for: The study began enrolling participants from 08th August 2025 and is unending, with an initial cohort of 235 expected to last approximately 5 years for each participant. Who is funding the study: hVIVO Services Limited Who is the main contact: Alex Mann - projectadmin@hvivo.com