Systemic Activity of Inhaled Hydrofluoroalkane-134a Metered Dose Inhaler with Beclomethasone Dipropionate in Children with Asthma

Abstract

Inhaled beclomethasone dipropionate (BDP) with the propellant hydrofluororoalkane-134a (HFA) has been designed to be equivalent in terms of safety to chlorofluorocarbon (CFC)- formulated metered dose inhalers (MDI). The purpose of this study was to assess whether inhaled BDP HFA MDI 100 µg b.i.d. was equivalent to BDP CFC MDI 100 µg b.i.d in terms of effects on short-term lower leg growth rate (LLGR) in children with asthma. Secondary aims were to assess effects on measures of hypothalamic-pituitary-adrenal (HPA) function. Seventeen boys and 13 girls with a mean age of 9.3 years were studied in a randomized double- blind cross over trial with three active, a run-in, and two wash-out periods, each of 2 weeks duration. Interventions were BDP HFA 100 µg, BDP CFC 100 µg, and BDP CFC 200 µg b.i.d delivered by the Volumatic™ spacer device. LLGR as measured by knemometry, 24-hour urine-free cortisol (UFC)/creatinine, and total cortisol metabolites (TCM)/creatinine were assessed. Mean (SD) LLGRs during run in and BDP HFA 100 µg, BDP CFC 100 µg, and 200 µg b.i.d. were 0.45 (0.44), 0.29 (0.24), 0.33 (0.26), and 0.31 (0.22) mm/week. The mean difference in LLGR between BDP HFA 100 µg and BDP CFC 100 µg b.i.d. was 0.02 mm/week with a one-sided 97.5% confidence interval lower end for the difference of 0.15 mm/week, thus, above the predefined noninferiority margin of –0.20 mm/week. UFC/creatinine and TCM/creatinine data showed no consistent variations. The systemic activity of BDP HFA 100 is equivalent to CFC 100 µg b.i.d., and children can be switched to the new HFA formulation without any risk of enhanced adverse systemic effects. (Pediatr Asthma Allergy Immunol 2006; 19[3]:172–179).