Switching patients from other inhaled corticosteroid devices to the Easyhaler(®): historical, matched-cohort study of real-life asthma patients

PURPOSE: To investigate the clinical and cost effectiveness of switching real-life asthma patients from other types of inhalers to the Easyhaler(®) (EH) for the administration of inhaled corticosteroids (ICS). PATIENTS AND METHODS: Historical, matched-cohort study of 1,958 asthma patients (children and adults) treated in UK primary-care practices, using data obtained from the Optimum Patient Care Research Database and Clinical Practice Research Datalink. Other inhalers (OH) included pressurized metered-dose inhalers, breath-actuated inhalers, and dry-powder inhalers, delivering beclomethasone, budesonide, fluticasone, or ciclesonide. Patients remaining on OH unchanged (same drug, dosage, and device; n=979) were matched 1:1 with those switched to the EH (beclomethasone or budesonide) at the same or lower ICS dosage (n=979), based on age, sex, year of index patient review/switch, most recent ICS drug, dosage, and device, and the number of severe exacerbations and average daily short-acting β(2) agonist (SABA) dosage in the preceding year. Clinical outcomes and health care costs were compared between groups for 12 months before and after the switch. Co-primary clinical outcomes were: 1) risk domain asthma control (RDAC) – no asthma-related hospitalization, acute oral steroid use, or lower respiratory tract infection (LRTI); 2) exacerbation rate (American Thoracic Society [ATS] definition) – where exacerbation is asthma-related hospitalization or acute oral steroid use; 3) exacerbation rate (clinical definition) – where exacerbation is ATS exacerbation or LRTI; and 4) overall asthma control (OAC) – RDAC plus average salbutamol-equivalent SABA dosage ≤200 μg/day. Non-inferiority (at least equivalence) of EH was tested against OH for the four co-primary outcomes in order (hierarchical approach) by comparing the difference in proportions of patients [EH-OH] achieving asthma control or having no exacerbations in the outcome year, using a limit of 10% difference. RESULTS: Non-inferiority was shown for the EH for all four co-primary outcomes. There were no significant differences between groups for RDAC or exacerbation rates, but EH patients were significantly more likely to achieve OAC (adjusted odds ratio [95% confidence interval]: 1.26 [1.05, 1.52]), as significantly more EH than OH patients had an average SABA dosage of ≤200 μg/day (52% versus 47%, respectively; P<0.001). Mean asthma-related health care costs increased from baseline to outcome years in both groups, but SABA costs increased significantly more in OH than EH patients (mean difference £5.5/patient/year) and consultation costs decreased significantly more in EH than OH patients (mean difference £13.5/patient/year). CONCLUSION: Typical asthma patients may be switched from other ICS devices to the Easyhaler(®) with no reduction in clinical effectiveness or increase in cost.