0796 Safety and efficacy of the combination of atomoxetine and oxybutynin for OSA treatment in children with Down Syndrome

Abstract Introduction Children with Down syndrome (DS) are at very high risk for obstructive sleep apnea (OSA), a prevalence of OSA 50-79%. Current treatments children DS have limited effectiveness, as positive airway pressure therapy is poorly tolerated and adenotonsillectomy not curative in most DS. The combination atomoxetine oxybutynin (ato-oxy) promising treatment adults. Ato-oxy has been shown to improve upper hypotonia, key feature DS, thus it may be particularly effective Methods We performed randomized, double-blind, crossover pilot trial examining the short-term efficacy ato-oxy 15 aged 6 17 years OSA. Participants received 4 weeks low dose (0.5 mg/kg 5 mg oxybutynin) well (1.2 random order. underwent polysomnography parent-reported health-related quality life assessment using OSA-18 baseline end each dosing period. primary study endpoint was reduction apnea-hypopnea index (oAHI) from baseline. Paired t-tests were used compare ato-oxy. Results participants qualified randomization 11 had complete data all points. Baseline oAHI 7.4 ± 3.7 (mean standard deviation), 3.6 3.3 (p=0.001 vs baseline) 3.9 2.8 (p=0.003 baseline). There no differences architecture or efficiency between either total score 51.5 18.5 baseline; improved 44.6 17.0 (p=0.09) 4-weeks ato-oxy; 45.5 15.7 (p=0.37) high-dose therapy. common adverse effects irritability fatigue, these generally mild. Conclusion Support (if any) Funding provided by NIH (HL151254 HD109777) Lumind-IDSC foundation.