Tirzepatide Versus Positive Airway Pressure for the Treatment of Obstructive Sleep Apnoea: A Randomised Comparative Effectiveness Trial

When used, continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA), a condition that is mainly caused by overweight and obesity. However, CPAP is plagued by poor adherence and high rates of discontinued use leaving most patients undertreated and at risk of serious health complications. This study aims to test whether new effective weight loss pharmacotherapy is superior to CPAP for alleviating OSA and improving health outcomes.

Inclusion Criteria: * Females and Males aged ≥ 18 years at the time of signing informed consent * Moderate-severe OSA defined as an AHI ≥ 15/hr determined from a Type 1 or 2 sleep study conducted within the previous 12 months with a clinician recommendation for CPAP therapy. * Moderate overweight or obesity defined as BMI ≥ 27 kg/m2. (Adjusted to BMI ≥ 25 kg/m2 for Asian populations as per WHO guidelines (WHO Expert Consultation (2004)) * No contraindication to tirzepatide use as per Australian Product Information * Home internet access to enable cloud storage of SleepTracker-AI in-home BDI. * Fluent English literacy and able to provide informed consent. Exclusion Criteria: OSA or other respiratory related criteria: * Respiratory failure including obesity hypoventilation syndrome (OHS) or daytime hypercapnia or moderate-severe chronic obstructive pulmonary disease (COPD) with FEV1/FVC ratio\50% respiratory events with Cheyne-Stokes Respiration (CSR) or Central Sleep Apnoea (CSA) * Relative or absolute contraindication to CPAP including chronic cranial injury; recurrent pneumothorax; indication for oral-pharyngeal surgery, significant craniofacial abnormalities that may affect breathing, or are unwilling to use CPAP * Any previous or planned surgery for OSA or major ear, nose or throat surgery, including tonsillectomy and adenoidectomy that still may affect breathing (NB: Inclusion of a participant with more minor ear, nose or throat surgery (for example, deviated septum) will be at the investigator's discretion) Glycaemia related criteria: * HbA1c ≥ 48 mmol/mol (6.5%) at screening * Type 1 or type 2 diabetes mellitus * Treatment with glucose-lowering agent(s) within 90 days before screening * Treatment with a GLP-1 receptor agonist within 90 days before screening Obesity related criteria: * A self-reported change in body weight \>5 kg or \>5% within 90 days before baseline * Treatment with medication for the indication of obesity within 90 days before baseline and/or currently enrolled in a weight loss program Other criteria: * Pregnancy/breast feeding or planning a pregnancy during the trial period * Relative or absolute contraindication to tirzepatide including needle phobia