Turner, Steve, Cotton, Seonaidh, Wood, Jessica, Bell, Victoria, Raja, Edwin Amalraj, Scott, Neil W., Morgan, Heather, Lawrie, Louisa, Emele, David, Kennedy, Charlotte, Scotland, Graham, Fielding, Shona, MacLennan, Graeme, Norrie, John, Forrest, Mark, Gaillard, Erol A., de Jongste, Johan, Pijnenburg, Marielle, Thomas, Mike, Price, David, Turner, Steve, Cotton, Seonaidh, Wood, Jessica, Bell, Victoria, Raja, Edwin Amalraj, Scott, Neil W., Morgan, Heather, Lawrie, Louisa, Emele, David, Kennedy, Charlotte, Scotland, Graham, Fielding, Shona, MacLennan, Graeme, Norrie, John, Forrest, Mark, Gaillard, Erol A., de Jongste, Johan, Pijnenburg, Marielle, Thomas, Mike, and Price, David
Background: The benefit of fractional exhaled nitric oxide (FeNO) in guiding asthma treatment is uncertain. We evaluated the efficacy of adding FeNO to symptom-guided treatment in children with asthma versus only symptom-guided treatment. Methods: RAACENO was a multicentre, parallel, randomised, controlled, phase 3 trial done in 35 secondary care centres and 17 primary care recruitment sites (only seven primary care sites managed to recruit patients) in the UK. Patients with a confirmed asthma diagnosis, aged 6–15 years, prescribed inhaled corticosteroids, and who received a course of oral corticosteroids for at least one asthma exacerbation during the 12 months before recruitment were included. Participants were randomly assigned to either FeNO plus symptom-guided treatment (intervention) or symptom-guided treatment alone (standard care) using a 24 h in-house, web-based randomisation system. Participants and the clinical and research teams were not masked to the group allocation. A web-based algorithm gave treatment recommendations based on the Asthma Control Test (ACT) or Childhood ACT (CACT) score; current asthma treatment; adherence to study treatment in the past 3 months; and use of FeNO (in the intervention group). Follow-up occurred at 3-month intervals for 12 months. The primary outcome was any asthma exacerbation treated with oral corticosteroids in the 12 months after randomisation, assessed in the intention-to-treat population. This study is registered with the International Standard Randomised Controlled Trial Registry, ISRCTN67875351. Findings: Between June 22, 2017, and Aug 8, 2019, 535 children were assessed for eligibility, 20 were ineligible and six were excluded post-randomisation. 509 children were recruited and at baseline, the mean age of participants was 10·1 years (SD 2·6), and 308 (60·5%) were male. The median FeNO was 21 ppb (IQR 10–48), mean predicted FEV1 was 89·6% (SD 18·0), and median daily dose of inhaled corticosteroids w