['Asthma guidelines recommend prescription of inhaled corticosteroids at a reduced dosage in children compared to older patients in order to minimize the systemic exposure and risk of unwanted side effects. In children, pressurized metered dose inhalers (pMDI) are recommended in combination with a valved holding chamber (VHC) to overcome the problem of coordinating inhalation with actuation. However, the influence of age and body size on the systemic exposure of drugs to be administered via a pMDI with VHC is still not fully elucidated. Therefore, we aimed to compare the systemic exposure to the active ingredients of a fixed combination of beclometasone-dipropionate/formoterol-fumarate administered via pMDI with VHC in children, adolescents and adults.', 'The pharmacokinetics of formoterol and beclometasone-17-monopropionate (active metabolite of beclometasone-dipropionate) was evaluated over 8\xa0h from three studies, each performed in a different age and body size group. Children (7-11 years, n\xa0=\xa020), adolescents (12-17 years, n\xa0=\xa029) and adults (≥18 years, n\xa0=\xa024) received a single dose of beclometasone/formoterol (children: 200\xa0μg/24\xa0μg, adolescents and adults: 400\xa0μg/24\xa0μg) via pMDI with AeroChamber Plus™.', 'The systemic exposure in children in comparison to adolescents was equivalent for formoterol while it was halved for beclometasone-17-monopropionate in accordance with the halved dose of beclometasone administered in children (90% CIs within 0.8-1.25 for formoterol and 0.4-0.625 for beclometasone-17-monopropionate). The systemic exposure to beclometasone-17-monopropionate and formoterol was equivalent between adolescents and adults.'] Is the systemic exposure to inhaled beclometasone/formoterol pMDI with valved holding chamber independent of age and body size?