 Subjects will be given an electronic peak flow recorder, symptoms diary and action plan for change in baseline symptoms. Participants will be asked to contact the clinic when they feel there has been a decline in asthma control and before they take rescue treatment, a clinic visit will be arranged. At this visit, all participants will have full medical assessment and clinical management based on detailed medical history, clinical findings and lung function measurement. Blood will be taken as part of this clinical assessment as outlined in the schedule of study procedures including biobanking of samples for whole blood gene expression, serum, plasma, sputum and urine. These samples will be stored for validation of additional biomarkers, aligned with the RASP-UK Refractory Asthma Stratification Programme-UK biomarker corticosteroid optimisation study. 