Clinical study

Sleep apnoea: coming soon: a pill that works while you sleep

The experimental drug reduced episodes of breathlessness by 56% and improved oxygenation. Now approaching Fda approval application

by Francesca Cerati

28 May 2025

3' min read

Key points

A concrete hope: the AD109 pill
How the pill works
And the side effects?
Next steps

3' min read

During the Covid-19 pandemic, many people heard about Cpap, that mask that helps to breathe by pushing air into the lungs, often used in intensive care units. But sleep apnoea sufferers know it for an entirely different reason: it has been the standard therapy for years, although often uncomfortable, cumbersome and difficult to endure in the long term. Now, however, a new discovery could change everything. A simple pill to be taken before going to sleep is proving to be a real and effective alternative.

A concrete hope: the AD109 pill

The pill in question is called AD109 and is currently in advanced clinical trials. The results just announced by the American biotech company Apnimed, which developed the drug, are very promising. In a six-month phase 3 clinical trial involving 646 adults with mild to severe obstructive sleep apnoea (OSA), those taking the drug had on average 56% fewer episodes in which breathing stopped or became too shallow during the night. Even more surprising: 22% of participants achieved almost complete control of the disease, with fewer than five episodes per hour, a result usually only achieved with very effective treatments.

How the pill works

But how does this pill work? AD109 is a combination of two already known active ingredients: atomoxetine, which has been used for years to treat Adhd, and aroxibutinine, a new version of a drug used against overactive bladder. Atomoxetine increases levels of norepinephrine, a neurotransmitter that helps keep throat muscles active during sleep, preventing them from collapsing. Aroxibutinin, on the other hand, blocks an inhibitory mechanism, allowing the genioglossus muscle - which lies at the base of the tongue and is crucial for keeping the airways open - to remain tonic during sleep. Together, the two drugs act on the neuromuscular cause of airway collapse, the real underlying problem of obstructive apnoea.

Unlike CPAP, which requires a mask attached to a machine that blows air into the throat to keep it open, AD109 is taken by mouth, once a day. This means it could represent a real revolution, especially for all those people who cannot tolerate CPAP or who use it intermittently. In the clinical study, in addition to the reduction in apnoea, researchers also observed an improvement in oxygenation during sleep, i.e. fewer dangerous drops in blood oxygen levels, which are associated with cardiovascular problems.

And the side effects?

So far, the drug has been well tolerated: no serious side effects have been reported. However, some experts, such as Dr Sigrid Veasey of the University of Pennsylvania, emphasise the importance of carefully monitoring possible side effects related to atomoxetine, which can slightly increase blood pressure and affect sleep quality. Dr. Najib Ayas, of the University of British Columbia, also points out that we do not yet know whether the pill improves patients' perceived symptoms, such as daytime sleepiness, or only measurable data in tests. And, of course, six months of observation is not enough to know whether AD109 will reduce the long-term risks of apnoea, such as heart attack, stroke or cognitive impairment.

However, there is much enthusiasm among experts. Dr Klar Yaggi, director of the sleep medicine programme at Yale University, speaks of exciting results and says that we are entering a new, more personalised phase of sleep medicine. No longer a one-size-fits-all approach, such as CPAP for every patient, but targeted therapies based on individual characteristics, and AD109 could be an important step in this direction.

A useful comparison is with tirzepatide, the injectable drug approved by the FDA in 2024 for obesity-related apnoea. But tirzepatide only works for those with excess weight, and its benefits come after months, as weight is lost. AD109, on the other hand, has been shown to be effective in the first few weeks, even in normal-weight people, and at all levels of apnoea severity.

Next steps

The next steps will be crucial. Apnimed will present complete data from the first clinical study this autumn and plans to complete a second study by the end of 2025. If all goes well, it will seek official approval from the FDA in early 2026.

Obstructive sleep apnoea is a serious but still underestimated disorder. It manifests itself as snoring, frequent awakenings, night-time suffocation and, over time, can increase the risk of hypertension, heart attack, stroke, diabetes and depression. Until now, treatment options were limited and often uncomfortable. But today, finally, a pill could change the rules of the game.