Pilot study in 15 stable male subjects with severe-to-very severe Chronic Obstructive Pulmonary Disease (COPD) to evaluate the effects of short term use of the Breathe Technologies noninvasive open ventilation (NIOV) system on respiratory mechanics during constant work rate exercise in subjects with severe COPD.

Study was a randomized double-blinded crossover design in which subjects completed a series of exercises at a constant work rate while using 1) Test noninvasive ventilation (NIOV) system powered by compressed air, 2) Test NIOV system powered by 100% oxygen, 3) nasal cannula oxygen, 4) nothing (Control). Subjects were assessed during constant work rate exercise as reflected by exercise duration, isotime oxygenation (SpO2), and isotime dyspnea score (Borg). Exercise sessions took place over 4 visits with each visit lasting approximately 5 hours.

Inclusion Criteria:

• Adult males, ≥ 40 years of age
• Diagnosis of severe COPD (GOLD stage III or IV) defined as having a FEV1 < 50% of predicted and an FEV1/FVC ratio < 70% of predicted
• Ventilatory limitation to exercise, documented by a VE/MVV > 0.85
• SpO2 between 80% and 88% during incremental exercise testing on room air
• Willingness and ability (after training) to exercise on a cycle ergometer
• Willingness and ability to perform all other study related procedures and tasks
• Ability to be properly fitted with the Breathe nasal mask
• Ability to tolerate and be appropriately titrated on the Breathe ventilator (See Appendix E)
• Ability to be properly fitted with an exercise mask
• Fluency in written and spoken English
• Provision of written informed consent

Exclusion Criteria:

• History of acute exacerbation of COPD within 30 days of screening
• History of serious epistaxis within 14 days of screening
• Requirement of > 5 LPM nasal O2 to maintain an SpO2 > 90% while at rest
• History of pneumothorax secondary to lung bullae
• History of intolerance to supplemental oxygen
• Musculoskeletal or other non-pulmonary impairment that limits exercise tolerance
• Inability to achieve an optimal CWR level (4-7 minutes) during Study Visit 1R
• Current participation in another interventional study or participation within 14 days of screening
• Presence of any condition or abnormality that in the opinion of the Principal Investigator may compromise the subject's safety or the quality of the study data

The primary endpoint is difference in endurance between cannula oxygen and NIOV+O2. Assuming 153 sec clinically important difference, 183 sec SD of increase and α=0.05, a sample size of 15 yields 85% power.

Continuously for up to 8 hours on study days in which exercise testing was conducted