An interventional study of Bilevel in OSA COPD Overlap Syndrome, sponsored by University of British Columbia. Not yet recruiting. Open to participants aged 41 Years and older. Per ClinicalTrials.gov, last updated 2026-10-23.
Sponsored by University of British Columbia · Not applicable, Interventional, and Treatment
This pilot study compares two positive airway pressure strategies for patients with both COPD and obstructive sleep apnea (overlap syndrome) who retain excess carbon dioxide. Thirty-two patients will be randomly assigned to either CPAP or high-intensity bilevel ventilation (BiPAP) for 12 months. The primary outcome is change in carbon dioxide levels. Secondary outcomes will be to evaluate the feasibility of conducting a larger multi-centre trial to guide treatment for this underserved population and other measures including sleep quality, respiratory symptoms, quality of life, treatment adherence, side effects, and safety.
Purpose: This pilot randomized controlled trial (RCT) compares two ventilation strategies delivered via bilevel positive airway pressure (BiPAP) in patients with chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) overlap syndrome (OVS) with chronic stable hypercapnia. The two strategies are an OSA-targeted approach (low pressure support, functionally equivalent to continuous positive airway pressure [CPAP]) and a high-intensity ventilation approach (high pressure support targeting correction of alveolar hypoventilation).
Justification: Co-existence of COPD and OSA, termed overlap syndrome (OVS), is estimated to affect 1% of the general population, and approximately 40% of these patients develop chronic stable hypercapnia, which is associated with overall poor prognosis. OVS patients have significantly higher overall and cardiovascular mortality than patients with COPD or OSA alone. Despite the high prevalence and poor prognosis of OVS, limited research has been done to optimize therapy. In particular, OVS patients have been systematically excluded from clinical trials for both COPD and obesity hypoventilation syndrome (OHS) populations. Clinicians are currently left to extrapolate treatment recommendations for OVS from two related but contradictory evidence bases. The American Thoracic Society (ATS), Canadian Thoracic Society (CTS), and European Respiratory Society (ERS) guidelines for chronic stable hypercapnic COPD recommend non-invasive ventilation (NIV) with high-intensity settings, while ATS guidelines for OHS recommend CPAP for patients with coexisting severe OSA. A direct comparison of ventilation strategies in OVS with chronic stable hypercapnia has been identified as a high research priority by the ATS research statement on OVS. This pilot trial addresses that evidence gap and will inform the design of a future large multi-center RCT.
Hypothesis: Investigators hypothesize that the OSA-targeted and high-intensity ventilation strategies will demonstrate equivalent efficacy in correcting hypercapnia in patients with OVS.
Objectives: The primary objective is determine changes in CO₂ with an OSA-targeted ventilation strategy, with comparison to high-intensity ventilation over a 12-month follow-up period. The secondary objective will be to evaluate feasibility of a larger multi-site RCT. This would include participant recruitment metrics (number of patients screened and enrolled), protocol completion rates (including adherence to data collection instruments), and patient-reported measures such as quality of life (COPD- and sleep-specific questionnaires), NIV side effects, and adherence to therapy (e.g. % of patients fulfilling criteria of >4 hours/night).
Research Design: Investigators will conduct an open-label, parallel-group, single-center, pilot RCT. Patient inclusion criteria: 1) COPD GOLD (Global Initiative for Chronic Obstructive Lung Disease) C or D; 2) FEV1 \< 50% predicted; 3) daytime PvCO2 (venous blood gas) on room air >50 mmHg; 4) OSA with moderate to severe obstructive AHI >=15event/hr based on PSG; 5) BMI >=30 kg/m2 6) Age >=40 years
Two arms (randomization to OSA-targeted vs high-intensity ventilation in a ratio of 1:1) will be compared. A titration polysomnography (PSG) will be conducted with the fitted mask to determine optimal device settings within 4 weeks of the baseline visit. Device data will be reviewed by study physicians initially weekly then monthly to adjust settings as needed to optimize treatment. Follow-up visits will be conducted at 1, 3, 6, and 12 months at the clinic and will include clinical assessment, venous blood gas, questionnaire administration, device adherence review, and adverse event monitoring. Feasibility outcomes including recruitment rate, protocol completion, and treatment adherence will be reported
191 studies on the registry are indexed under Hypercapnia; 36 are open to participants now.
This study's planned enrollment of 32 is below the median of 48 across 144 interventional studies indexed under Hypercapnia.
Browse Hypercapnia studies →University of British Columbia is the lead sponsor of 1,335 studies on the registry; 256 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 1 (17%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria
Bilevel settings optimized to specifically address upper airway obstruction
Device: Bilevel
Higher pressure support targeting increased tidal volume
Device: Bilevel
Bilevel device can be used for ventilation support to address upper airway obstruction, augment tidal volume.
changes in venous carbon dioxide level
Determine changes in venous carbon dioxide value with an OSA-targeted ventilation strategy, with comparison to high-intensity ventilation
Time frame: 12 months
Number of participants screened and enrolled
Number of participants screened for eligibility and number enrolled in the study.
Time frame: 12 months
Severe Respiratory Insufficiency Questionnaire
The Severe Respiratory Insufficiency Questionnaire is scored on a scale of 0 to 100, with higher scores indicating better health-related quality of life.
Time frame: 12 months
Protocol completion rate
Proportion of enrolled participants who completed the study protocol.
Time frame: 12 months
Epworth Sleepiness Scale
The Epworth Sleepiness Scale is scored on a scale of 0 to 24, with higher scores indicating greater daytime sleepiness.
Time frame: 12 months
S3-Non Invasive Ventilation Questionnaire
The total score ranges from 0 to 10, with lower scores indicating greater discomfort associated with non-invasive ventilation device.
Time frame: 12 months
Device adherence
The proportion of participants using the device for more than 4 hours per night.
Time frame: 12 months
No study locations are listed for this record.
Plan to share: No — Individual participant data will not be shared outside of the research team due to considerations regarding participant privacy and confidentiality. Aggregate results will be reported.
Start is estimated for Nov 2026; primary completion for Nov 2028, 24 months later.
Of 58 non-industry interventional studies with no phase under Hypercapnia, half reached primary completion within 21 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 42. This study's planned 24 months is above that.
Counting every sponsor, half of 64 studies reached it within 21 months; a quarter within 7 and three quarters within 34.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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