The Breathe NIOV™ System will reduce the work of breathing in subjects with chronic respiratory insufficiency who require long-term oxygen therapy (LTOT). The Breathe system will accomplish this by providing oxygen under pressure and augmenting the subject's spontaneous tidal volumes. The combination of efficient oxygen delivery, assisted ventilation, and a comfortable low-profile device, will result in a mean improvement in perceived well-being and ability to perform ADLs, as measured by patient-reported outcome (PRO) instruments.

This will be a prospective, open-label, crossover study in up to 12 stable subjects with chronic respiratory insufficiency who require LTOT. Each subject's standard oxygen therapy will be used as the control treatment and compared to the test ventilator system during selected activities of daily living. Subjects will participate in the study for up to 9 home visits, with Visits 1 and 2 each lasting for approximately 4 hours, and Visits 3-9 lasting approximately 1-2 hours each. Subjects may discontinue study participation at any time.

Inclusion Criteria:

• Adult male and female subjects, 21-80 years of age
• Diagnosis of chronic respiratory insufficiency including COPD and interstitial lung disease
• Requires use of continuous nasal oxygen of at least 2 lpm
• Reports limitation of activity due to fatigue or breathlessness
• Fluent in written and spoken English language
• Ability to be properly fitted with the Breathe nasal mask
• Ability to tolerate and be appropriately titrated on the Breathe ventilator
• Ability to communicate self-assessment of dyspnea, comfort, and fatigue
• Ability and willingness to participate in the study including walking and other activities of daily living
• Ability to provide written informed consent

Exclusion Criteria:

• Recent history of frequent or severe epistaxis
• Symptoms of acute respiratory exacerbation within 48 hours of Study Day 1
• Discharge from the hospital within 30 days of study enrollment
• Subjects, who in the opinion of the Investigator, are not suitable candidates for enrollment or who are unlikely to be able to comply with trial requirements
• Subjects with conditions that, in the Investigator's opinion, contraindicates study participation