BackgroundIntranasal corticosteroids are the mainstay of allergic rhinitis (AR) treatment. Their potential to suppress the hypothalamic-pituitary-adrenal axis should be evaluated, especially after long-term daily use in children. ObjectiveTo evaluate the effects of treatment with non-aqueous beclomethasone dipropionate (BDP) nasal aerosol on hypothalamic-pituitary-adrenal axis function in children with perennial AR. MethodsIn this double-blinded, placebo-controlled, parallel-group study, patients (6–11 years old) with perennial AR were randomized (2:1) to BDP nasal aerosol at 80 μg/day (n = 67) or placebo (n = 32). The primary end point was change from baseline in 24-hour serum cortisol (SC) weighted mean for BDP nasal aerosol and placebo after 6 weeks of treatment, which was analyzed in the per-protocol population. ResultsThe per-protocol population included 97 patients (BDP nasal aerosol, n = 66; placebo, n = 31). Baseline geometric mean SC weighted mean values were similar in the 80-μg/day BDP nasal aerosol and placebo groups (5.97 and 6.47 μg/dL, respectively). After 6 weeks’ treatment, geometric mean values were 6.19 and 7.13 μg/dL, respectively, with no decrease from baseline in either group. Geometric mean SC ratio of BDP nasal aerosol at 80 μg/day to placebo was 0.91 (95% confidence interval 0.81–1.03), indicating predefined noninferiority. SC concentration-time profiles were similar for the placebo and 80-μg/day BDP nasal aerosol groups at baseline and week 6. BDP nasal aerosol at 80 μg/day was generally well tolerated. ConclusionIn pediatric patients with perennial AR, 24-hour SC profiles were comparable for BDP nasal aerosol and placebo, indicating that once-daily BDP nasal aerosol treatment did not significantly affect hypothalamic-pituitary-adrenal axis function. Trial RegistrationClinicalTrials.gov; NCT01697956.