Portable Oxygen Concentrator (POC) Versus Standard of Care in Long-COVID: Randomized Crossover Exploratory Pilot Study.

After a 2-week screening/baseline evaluation, participants will be randomized in a 1:1 allocation ratio to one of the following 2 sequences: 1) portable oxygen concentrator (POC) for a first 2-week period followed by standard of care (SOC) for a second 2-week period or 2) SOC for a first 2-week period followed by POC for a second 2-week period. There will be a washout period of one week between the two treatment periods. A total of 10 subjects will be enrolled per sequence.

Inclusion criteria

• Ability and willingness to give written informed consent prior to any study-specific screening procedures and to comply with the requirements of the study
• Male or female, aged ≥ 18 years of age
• Diagnosed with Long-COVID
• Patient self-reported concerns regarding cognitive functioning or recent diagnosis of COVID-19 related cognitive impairment
• MoCA test scores ranging from 13 to 25/30 at screening
• Oxygen saturation SpO2 ≤ 93 % on fingertip pulse oximetry and/or < 60% on brain NIRS, at rest or during effort and/ or 10% relative decrease in brain saturation during exercise as compared to baseline value at screening
• Ability to perform exercise treadmill test at screening
• Tolerability of pulsed oxygen (O2) therapy delivered by POC at screening
• Willingness and ability to wear POC.

Exclusion criteria

• Contraindication to the use of POC including allergy to cannula material
• Pregnancy or planning to become pregnant during the study
• Non-COVID-related cause for cognitive impairment (such as Parkinson's disease, multiple sclerosis, Alzheimer's disease, stroke, brain tumor, or dementia)
• Subjects with respiratory infection at screening or randomization and/or acute bronchitis requiring antibiotics at the time of randomization or expected during the treatment
• Participation in other interventional clinical trial within 30 days of randomization or expect to participate in any other investigational clinical trial during the conduct of this trial
• Subjects who should be excluded in the opinion of the investigator