Asthma control with ICS-formoterol reliever versus maintenance ICS and SABA reliever therapy: a post hoc analysis of two randomised controlled trials

Background: In randomised controlled trials, as-needed inhaled corticosteroid (ICS)-formoterol reliever therapy reduces severe exacerbation risk compared with maintenance ICS plus short-acting beta2-agonist (SABA) reliever in adolescent and adult asthma, but results in slightly worse control of asthma symptoms, as measured by mean Asthma Control Questionnaire-5 (ACQ-5) score. Objective: To assess the levels and changes in asthma control for as-needed budesonide-formoterol versus maintenance budesonide plus SABA in post hoc analyses from the Novel START and PRACTICAL clinical trials. Methods: The number and proportion of participants at study end in each ACQ-5 category ('well-controlled', 'partly controlled' or 'inadequately controlled' symptoms), and in each responder category based on the minimal clinically important difference for ACQ-5 of 0.5 (improved, no change and worse) with as-needed budesonide-formoterol and maintenance budesonide plus SABA treatment were calculated. Results: With last observation carried forwards, 189/214 (88.3%) and 354/434 (81.6%) of patients in the budesonide-formoterol group had 'well-controlled' or 'partly controlled' symptoms at the end of the study, vs 183/214 (85.5%) and 358/431 (83.1%) in the budesonide maintenance group, for Novel START and PRACTICAL, respectively. The proportion of patients whose symptom control was either improved or unchanged from baseline was 190/214 (88.8%) and 368/434 (84.8%) for budesonide-formoterol, vs 185/214 (86.4%) and 376/431 (87.2%) for maintenance budesonide, in Novel START and PRACTICAL respectively. Conclusions: There were no clinically important differences in the proportions of patients with 'well-controlled' or 'partly controlled' asthma symptoms, or proportions who improved or maintained their level of control, with as-needed budesonide-formoterol versus maintenance budesonide plus SABA.