Eli Lilly and Company has announced positive topline results from the SURMOUNT-OSA Phase III clinical trials, indicating that its tirzepatide therapy has the potential to reduce the severity of sleep apnoea in adults with obstructive sleep apnoea (OSA) and obesity.

The multicentre, double-blind, randomised, parallel, placebo-master protocol SURMOUNT-OSA compared the safety and efficacy of tirzepatide versus placebo over 52 weeks.

SURMOUNT-OSA included two studies targeting different patient groups with moderate-to-severe OSA and obesity.

Study one involved patients who were unable or unwilling to use positive airway pressure (PAP) therapy while study two included those who were on and planned to remain on PAP therapy throughout the trial.

The trials enrolled a total of 469 participants across nine countries, including the US, Australia, Brazil, China, Czechia, Germany, Japan, Mexico, and Taiwan.

The primary objective of the studies was to demonstrate tirzepatide's superiority in change in the apnea-hypopnea index (AHI) from baseline at 52 weeks versus placebo.

Results from study one showed that treatment with tirzepatide offered a mean AHI reduction from baseline of 27.4 events per hour, significantly more than the 4.8 events per hour reduction seen with a placebo.

Additionally, tirzepatide resulted in a mean decline in body weight of 18.1% from baseline, versus 1.3% for placebo.

In study two, tirzepatide also demonstrated a significant mean AHI reduction from the baseline of 30.4 events per hour, compared to six events per hour for the placebo.

Furthermore, the therapy offered a mean reduction in body weight of 20.1% from baseline, as against 2.3% for placebo.

The safety profile of the treatment in the SURMOUNT-OSA studies was in line with that of prior SURMOUNT and SURPASS trials.

The most commonly reported adverse events were gastrointestinal-related and were generally mild to moderate in severity.

A glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, tirzepatide is an approved treatment for chronic weight management.

Eli Lilly product development senior vice-president Jeff Emmick said: “OSA impacts 80 million adults in the US, with more than 20 million living with moderate-to-severe OSA. However, 85% of OSA cases go undiagnosed and therefore untreated.

“Addressing this unmet need head-on is critical, and while there are pharmaceutical treatments for the excessive sleepiness associated with OSA, tirzepatide has the potential to be the first pharmaceutical treatment for the underlying disease.”

The latest development comes after the company commenced Phase III clinical trials of oral medication, orforglipron, for weight loss, in India.