Oral orforglipron eased sleep apnoea in two year-long phase 3 trials

A once-daily pill in the GLP-1 class reduced the severity of obstructive sleep apnoea in adults with obesity, in two year-long phase 3 trials published in JAMA [s1]. Orforglipron is an oral drug rather than an injection, which is part of why its results draw attention. But the effect was measured against placebo in a selected population, the drug is not approved for sleep apnoea, and gastrointestinal side effects were common — so the finding is best read as evidence of promise, not a settled treatment.

Why a weight drug is being tested for apnoea

Obstructive sleep apnoea (OSA) is the repeated collapse of the upper airway during sleep, and excess weight is one of its strongest drivers. Losing weight has long been known to ease it, which is the logic behind testing drugs that cause weight loss. Orforglipron is an oral GLP-1 receptor agonist; most drugs in this family are injected, so a tablet that works would be a practical shift. The question these trials set out to answer was narrow and specific: does it reduce apnoea itself, not just weight?

What the trials did

The researchers ran two 52-week, phase 3, double-blind, placebo-controlled randomised trials at 66 sites across the US, Argentina, Brazil, China, the Czech Republic, Germany, Japan, Mexico and Taiwan [s1]. Adults with moderate-to-severe OSA and a body-mass index of 27 or higher were enrolled between 11 November 2024 and 23 July 2025, with final follow-up on 30 July 2026 [s1]. The two trials differed in one important way: trial 1 enrolled people not using positive airway pressure (PAP) therapy, while trial 2 enrolled people who were [s1]. The programme is registered as NCT06649045 [s2].

Participants were randomised one-to-one to once-daily orforglipron, at a maximum tolerated dose equivalent to a 9, 14.5 or 17.2 mg tablet, or to placebo [s1]. The primary endpoint was the change in the apnoea–hypopnoea index (AHI) — the number of breathing interruptions per hour of sleep, the standard measure of OSA severity — from the start to week 52 [s1].

Trial 1 randomised 363 patients (mean age 48.4 years, mean BMI 37.4, mean AHI 50.7 events an hour) and trial 2 randomised 349 (mean age 51.1, mean BMI 38.6, mean AHI 57.6) [s1]. Both groups therefore began with, on average, severe apnoea.

What they found

In trial 1, the AHI fell by a mean of 17.8 events an hour on orforglipron versus 4.5 on placebo — a difference of 13.2 (95% confidence interval −17.7 to −8.7) [s1]. In trial 2, among people already using PAP, it fell by 17.3 on the drug versus 5.3 on placebo, a difference of 12.0 (−17.1 to −6.9) [s1]. Both differences were statistically significant [s1]. Of seven ranked secondary endpoints, six favoured orforglipron [s1].

The main downside was tolerability. Gastrointestinal events were the most common side effect, reported by 68.0% of orforglipron patients versus 37.4% on placebo in trial 1, and by 70.6% versus 36.6% in trial 2 [s1] — roughly twice as many as on placebo, consistent with the known profile of GLP-1 drugs.

How to read it

The improvement is real and measured by the right yardstick: AHI, not a proxy. But a few things keep it in proportion. The participants had obesity and, on average, severe apnoea, so the results speak to that group rather than to everyone with OSA. Even after a mean drop of around 17 events an hour, many participants starting above 50 would still have had apnoea in the moderate range — a meaningful reduction is not the same as a cure, and the trials measured breathing during sleep rather than long-term outcomes such as cardiovascular events. The two-to-one rate of gastrointestinal side effects also matters for whether people can stay on a drug for the months it takes to benefit.

Crucially, orforglipron is not approved for obstructive sleep apnoea, and these results — sponsored and part of a wider development programme for the drug — describe what happened in controlled trials, not established practice [s1]. The authors frame the findings as evidence for the drug's "potential use" in this setting [s1].

What to watch

The open questions are whether regulators accept AHI reduction as a basis for an OSA indication for an oral drug, how the benefit compares with PAP and with injectable weight drugs already being studied for apnoea, and whether the breathing improvements translate into the outcomes patients care about — daytime function and cardiovascular risk — over longer follow-up. For now, the headline is that a pill, not just an injection, moved the needle on sleep apnoea in two large trials [s1].

This article describes clinical-trial results and is not medical advice. Anyone with sleep apnoea should discuss treatment, including whether to continue PAP, with their own clinician.