START CARE: a protocol for a randomised controlled trial of step-wise budesonide-formoterol reliever-based treatment in children.

Background: Asthma is the most common chronic childhood respiratory condition globally. Inhaled corticosteroid (ICS)-formoterol reliever-based regimens reduce the risk of asthma exacerbations compared with conventional short-acting ß2-agonist (SABA) reliever-based regimens in adults and adolescents. The current limited evidence for anti-inflammatory reliever therapy in children means it is unknown whether these findings are also applicable to children. High-quality randomised controlled trials (RCTs) are needed. Objective: The study aim is to determine the efficacy and safety of budesonide-formoterol reliever alone or maintenance and reliever therapy (MART) compared with standard therapy: budesonide or budesonide-formoterol maintenance, both with terbutaline reliever, in children aged 5 to 11 years with mild, moderate and severe asthma. Methods: A 52-week, multicentre, open-label, parallel group, phase III, two-sided superiority RCT will recruit 400 children aged 5 to 11 years with asthma. Participants will be randomised 1:1 to either budesonide-formoterol 100/6 µg Turbuhaler reliever alone or MART; or budesonide or budesonide-formoterol Turbuhaler maintenance, with terbutaline Turbuhaler reliever. The primary outcome is moderate and severe asthma exacerbations as rate per participant per year. Secondary outcomes are asthma control, lung function, exhaled nitric oxide and treatment step change. Assessment of Turbuhaler technique and cost-effectiveness analysis are also planned. Conclusion: This will be the first RCT to compare the efficacy and safety of a step-wise budesonide-formoterol reliever alone or MART regimen with conventional inhaled ICS or ICS-long-acting ß-agonist maintenance plus SABA reliever in children. The results will provide a much-needed evidence base for the treatment of asthma in children.