ABSTRACT. Objective. To assess the long-term safety of hydrofluoroalkane 134a (HFA)-beclomethasone dipropionate (BDP) extrafine aerosol administered by the Autohaler compared with chlorofluorocarbon (CFC)-BDP administered by a press-and-breathe metered-dose inhaler (pMDI) and spacer (؉S) in the treatment of children with asthma.Methods. This 12-month, open-label, randomized, multicenter study enrolled 300 children who were aged 5 to 11 years and had well-controlled asthma on inhaled CFC-BDP or budesonide; 256 patients were using doses within the recommended range (200 -400 g) and were analyzed separately. Patients were randomized in a 1:3 ratio to continue on CFC-BDP؉S at approximately the same dose as they were using before study entry or switch to HFA-BDP at half the daily dose.Results. Asthma control was well maintained in the HFA-BDP group as evidenced by lung function tests and asthma symptoms compared with CFC-BDP؉S at approximately twice the dose. There were no significant differences between the HFA-BDP 100 to 200 g and CFC-BDP؉S 200 to 400 g treatment groups in mean change from baseline in height (5.23 cm vs 5.66 cm at month 12, respectively) or mean growth velocity from day 1 to month 12 (5.27 cm/y vs 5.71 cm/y, respectively). There were no significant differences between groups in adrenal function tests or markers of bone metabolism.Conclusions. In this long-term study in children with asthma, extrafine HFA-BDP provided long-term maintenance of asthma control at approximately half the dose compared with CFC-BDP؉S. There were no clinically meaningful differences between HFA-BDP extrafine aerosol and conventional CFC-BDP؉S with regard to growth or other systemic effects. Pediatrics 2002;109(6). URL: http://www.pediatrics.org/cgi/content/full/109/6/ e92; children, asthma, inhaled corticosteroid, CFC-free, hydrofluoroalkane-134a beclomethasone dipropionate, growth.ABBREVIATIONS. BDP, beclomethasone dipropionate; CFC, chlorofluorocarbon; HFA, hydrofluoroalkane; pMDI, press-andbreath metered-dose inhaler; ϩS, plus spacer; FEV 1 , forced expiratory volume in 1 second; PEF, peak expiratory flow; PICP, carboxy propeptide of procollagen type 1; 1-CTP, 1-collagen telopeptide; ACTH, adrenocorticotrophic hormone; UFC, urinary free cortisol; EPX, eosinophilic protein X; CI, confidence interval.