TUESDAY, May 26, 2026 (HealthDay News) -- For patients with obstructive sleep apnea (OSA) unable to use positive airway pressure (PAP), AD109 (investigational fixed-dose oral combination of aroxybutynin 2.5 mg/atomoxetine 75 mg) improves airway obstruction and oxygenation at 26 weeks, according to research published online May 18 in the American Journal of Respiratory and Critical Care Medicine to coincide with the American Thoracic Society 2026 International Conference, held from May 15 to 20 in Orlando, Florida.
Patrick J. Strollo Jr., M.D., from the Veteran Affairs Pittsburgh Healthcare System, and colleagues examined the efficacy and safety of AD109 over six months in a diverse OSA population who were intolerant to or refused PAP in a randomized, double-blind, 26-week parallel arm trial of AD109 versus placebo. Change from baseline to week 26 in apnea-hypopnea index (AHI) was examined as the primary efficacy end point.
A total of 646 eligible participants were randomly assigned to AD109 or placebo. At baseline, the median AHI was 19.6 events/hour, with 35, 42, and 23 percent mild, moderate, and severe OSA, respectively. The researchers found that the mean AHI treatment difference was −4.0 events/hour at week 26, representing a model-estimated 44.1 versus 17.6 percent decrease from baseline. Improvements in the oxygen desaturation index and hypoxic burden were seen with AD109 versus placebo at week 26, but no significant difference was seen for the Patient-Reported Outcomes Measurement Information System-Fatigue T score. Overall, 21.2 and 3.1 percent of participants receiving AD109 and placebo, respectively, discontinued therapy due to adverse events. Dry mouth, nausea, insomnia, and urinary hesitation were the most common adverse events with AD109. There were no serious treatment-related adverse events reported.
"These results provide encouraging evidence that targeting neuromuscular dysfunction can translate into meaningful clinical outcomes, aligning with our evolving understanding of the disease biology," Strollo said in a statement.
Several authors disclosed ties to the biopharmaceutical and medical device industries.
