PRISTINE - Personalised Approach to Improve aSThma prescrIbing iN childrEn

Asthma is one of the most common chronic diseases affecting children in the UK. Poorly controlled asthma manifests with chronic cough, wheeze and shortness of breath which in-turn has a significant negative impact on a child's quality of life, interfering with sleep, impairing exercise ability and resulting in frequent school absences and hospital admissions. Management of paediatric asthma in the UK is directed by the British Thoracic Society (BTS) Guidelines, which recommend a stepwise (one to five) treatment plan. Step three of the management guideline for children aged 5-12 years of age recommends the addition of the preventer inhaled medication, including long-acting β2 agonists such as salmeterol. However, there is a wide variation in response to this medication with approximately one in seven people, with a specific genetic change, found to have an increase in asthma symptoms in association with the use of thisiss medication. A related medicine, formoterol, is used less commonly in children with asthma. In this study, the investigators will aim to identify children with asthma whose symptoms are poorly controlled on inhaled long-acting beta2 agonists. Via a simple saliva test, the investigators will identify the presence or absence of the specific genetic change potentally influencing the effectiveness of treatment with salmeterol or related longacting beta2 agonists thus enabling the investigators to recommend either salmeterol or an alternative medication for the treatment plan such as montelukast. The investigators will randomise the patients into two groups; to receive "personalised care" where the choice of controller medication would be based on the child's gene test results and predicted response to long-acting beta2 agonists, or "standard care" following the BTS guidelines at the clinician's discretion without knowledge of the gene test results. The investigators aim to measure whether this individualized approach to asthma prescribing results in im