Effect of Hi-OxSR for the Treatment of Post COVID Condition

NCT06928506 | Recruiting DMC

• 1 other identifier: 21-6203-HiOxSR
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 3

Brief Summary

The RECLAIM study platform will be used to explore whether the use of the Hi-OxSR device improves the symptoms of post covid cognitive dysfunction. Carbon dioxide (CO2) has been proposed as a potential treatment for persistent immune activation as there is evidence that CO2 has antioxidant, anti-inflammatory, and anti-cytokine effects. We conducted a pilot study assessing the open label use of re-breathing CO2 (using Hi-OxSR) twice a day for 14 days, for the treatment of post-COVID cognitive dysfunction. Significant improvements were found in multiple cognitive assessments using TestMyBrain cognitive tests and brain fog (MSNQ) and fatigue scores. This phase 2 clinical trial seeks to build on current findings to determine the optimal effective dose of treatment (i.e. length of use, oxygen concentration, without or without CO2 rebreathing) and the safety of using Hi-OxSR in this patient population.

Conditions

Long COVID; Post COVID-19 Condition; Post Acute Sequelae of COVID-19

Outcome Measures

Primary Outcomes (2)

• Simple reaction time (SRT) task from the TestMyBrain (TMB) Digital Neuropsychology Toolkit On-line survey tool

  TestMyBrain was developed as a tool to collect large, population-based samples for understanding the relationship between cognition, emotion, social functioning, and health. This test will take about 5 minutes to complete and will assess reaction time.

  Baseline/Start of intervention to two months

• Verbal paired associates (VPA) task from the TestMyBrain (TMB) Digital Neuropsychology Toolkit On-line survey tool

  TestMyBrain was developed as a tool to collect large, population-based samples for understanding the relationship between cognition, emotion, social functioning, and health. This test will take about 5 minutes to complete and will assess memory.

  Baseline/Start of intervention to two months

Secondary Outcomes (14)

• All cognitive performance tasks (measured by the TESTMYBRAIN.org (TMB) neuropsychology toolkit

  Baseline/start of intervention to 2 weeks, 1, 2 and 6 months

• Brain Fog Questionnaire

  Baseline/start of intervention to 2 weeks, 1, 2 and 6 months

• Brief Fatigue Inventory

  Baseline/start of intervention to 2 weeks, 1, 2 and 6 months

• Short Form (SF)-36

  Baseline/start of intervention to 2 weeks, 1, 2 and 6 months

• Safety, adverse events and serious adverse events

  Baseline/start of intervention to 6 months

Study Arms (3)

Group 1

EXPERIMENTAL

Use of Hi-OxSR for 30 minutes twice a day at low oxygen flow (0.5-3 liters per minute) for 2 weeks.

Device: Hi-OxSR device

Group 2

EXPERIMENTAL

Use of Hi-OxSR for 30 minutes twice a day at low oxygen flow (0.5-3 liters per minute) for 4 weeks.

Device: Hi-OxSR device

Group 3

ACTIVE COMPARATOR

Use of Hi-Ox for 30 minutes twice a day at high oxygen flow (5 liters per minute) for 2 weeks.

Device: Hi-Ox device

Interventions

Hi-OxSR device DEVICE

The Hi-OxSR device consists of the Hi-Ox mask connected to a portable oxygen concentrator, with added tubing serving as a reservoir for rebreathed exhaled breath.

Group 1; Group 2

Hi-Ox device DEVICE

The Hi-Ox mask is connected to a portable oxygen concentrator.

Group 3

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years;
• Positive COVID-19 test by nasopharyngeal swab RT-PCR (reverse transcription polymerase chain reaction) test, antibody or antigen tests at least 3 months prior to randomization; OR Presumed COVID-19 assessed by the site investigator (no positive COVID-19 test) with acute illness after October 15, 2019.
• Patients should be treated with standard of care therapies (as discussed in the study manual) for at least 4 weeks prior to entry into trial.
• Lingering COVID-19 symptoms beyond 3 months from onset of acute COVID and symptoms have lasted at least 2 months. The onset of COVID is considered the earliest of two dates: the date of positive test or the date of first symptoms;
• Lingering symptoms from COVID-19 present at the time of randomization. "Lingering symptoms of Long COVID" must include self-reported cognitive dysfunction symptoms.
• Female patients of childbearing potential (as assessed by the overseeing Investigator) who are sexually active must agree to practice true abstinence or use effective methods of contraception while on study treatment. Effective methods of contraception must be discussed and approved by the overseeing Investigator.
• Must be able to provide informed consent and both willing and able to comply with study requirements.
• Oxygen saturation on room air ≥92% at screening measured by pulse oximeter.

You may not qualify if:

• Patients who had mechanical ventilation or extracorporeal membrane oxygen (ECMO) for COVID-19;
• Current end-organ failure, organ transplantation, or current hospitalization in acute care hospital;
• Contraindications to all of the study interventions;
• Co-enrolment in another interventional trial (co-enrolment in an observational study is permitted);
• Currently pregnant or breastfeeding.
• Known physician diagnosis of cognitive dysfunction prior to COVID infection
• Use of an investigational drug/device or other interventions within 30 days of screening
• Use of home oxygen (O2) at baseline
• History of pulmonary hypertension
• Interstitial pulmonary fibrosis
• Moderate to severe chronic obstructive pulmonary disease (COPD)
• History of narcolepsy
• Presence of a condition or abnormality that in the opinion of the investigator would compromise the safety of the participant or the quality of the data.

Sponsors & Collaborators

• University Health Network, Toronto: lead

Study Sites (3)

Kaye Edmonton Clinic

Edmonton, Alberta, Canada

NOT YET RECRUITING

University Health Network

Toronto, Ontario, M5G 2C4, Canada

RECRUITING

Centre Hospitalier Universitaire de Sherbrooke

Sherbrooke, Quebec, Canada

NOT YET RECRUITING

MeSH Terms

Conditions

Post-Acute COVID-19 Syndrome

Condition Hierarchy (Ancestors)

COVID-19; Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases; Post-Infectious Disorders; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Angela M Cheung, MD, PhD

  University Health Network, Toronto

  PRINCIPAL INVESTIGATOR

Central Study Contacts

suzanne Cohen

CONTACT

1-866-673-2524; reclaim@uhn.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participants are not be blinded to group allocation, and will know what group they are assigned to. Participants will be masked to the hypothesis of the study.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: RECLAIM is a Canada-wide phase ll/lll, prospective, adaptive randomized controlled platform trial that is intended to study various interventions for the treatment of long COVID. Participants in the Hi-OxSR sub-protocol will be randomized in a 1:1:1 ratio to one of 3 arms.

Study Record Dates

• First Submitted: April 11, 2025
• First Posted: April 15, 2025
• Study Start: August 1, 2025
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2028
• Last Updated: September 15, 2025

Record last verified: 2025-08

Locations

CA (3)