Apnimed firms up filing plans for oral sleep apnoea drug after second pivotal study win

Apnimed followed up the first Phase III success for its obstructive sleep apnoea (OSA) therapy AD109 with a second win, announcing Wednesday that the late-stage LunAIRo study has also achieved its primary endpoint. The positive readout solidifies the company's plans to file for FDA approval of the oral once-daily anti-apneic neuromuscular modulator in early 2026.

"With two large Phase III studies now demonstrating a consistent and significant efficacy profile for AD109, we are closer to delivering the first oral pharmacotherapy for…OSA," remarked CEO Larry Miller. In May, Apnimed reported that the six-month SynAIRgy study had achieved its primary endpoint, with AD109 demonstrating a mean 55.6% reduction from baseline in the apnoea-hypopnea index (AHI) at 26 weeks.

The 12-month LunAIRo trial enrolled 660 adults with mild, moderate and severe OSA who are intolerant of or currently refuse continuous positive airway pressure therapy. Apnimed noted that those recruited represent a real-world OSA population. Participants were randomised to receive AD109 — a fixed-dose combination of the antimuscarinic aroxybutynin and the selective norepinephrine reuptake inhibitor atomoxetine — or placebo, with the primary endpoint assessed at 26 weeks.

According to top-line results, AD109 demonstrated clinically meaningful and statistically significant reductions in airway obstruction, with the therapy achieving a mean reduction in AHI of 46.8% from baseline at week 26, versus 6.8% for placebo. The AHI reduction remained significant at the end of the study at week 51, the company said.

Results for secondary and exploratory endpoints showed meaningful improvements in oxygenation, whilst AD109 improved OSA disease severity for 45% of participants at week 26, and 47.5% at week 51. In addition, AD109 achieved OSA complete disease control for 22.9% of patients at week 26, and 22.5% at week 51.

AD109 was also generally well tolerated in the trial, with no drug-related serious adverse events, Apnimed said. Further findings from both the LunAIRo and SynAIRgy studies are set to be presented at a medical congress later this year.