Safety and Efficacy of Hyperbaric Oxygen Therapy for Long COVID Syndrome

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

PHASE2

Total Enrollment

80 participants

Study Classification

INTERVENTIONAL

Study Start Date

2021-09-15

Study Completion Date

2024-06-17

Brief Summary

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Long COVID Syndrome (Long COVID), Post Acute COVID-19 Syndrome (PACS) or Post COVID-19 Syndrome (PCS) is defined as 'signs and symptoms that develop during or following an infection consistent with COVID-19, continue for more than 12 weeks and are not explained by an alternative diagnosis'. 1 in 10 infected individuals may suffer persistent symptoms, and we are facing an emerging problem that will severely affect individuals, health care systems and society for years to come.

We explore hyperbaric oxygen administered in a randomized placebo-controlled clinical trial as a potential treatment for patients suffering from Long COVID.

The overall hypothesis to be evaluated is that hyperbaric oxygen (HBO2) alleviates symptoms associated with Long COVID.

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Detailed Description

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Phase II Clinical Trial

Prospective randomized, placebo-controlled, double blind, phase II, clinical trial, estimated enrolment: 80 subjects Parallel groups Intervention: HBO2: 240 kPa for 90 min, maximum 10 treatments within 6 weeks from randomization

Control: Placebo treatment with 'sham' air breathing at a moderately higher pressure (134 kPa) to simulate hyperbaric chamber treatment, maximum 10 treatments within 6 weeks from randomization

The population will comprise of previously healthy patients (American Society of Anaesthesiologists (ASA) class 1-2 diagnosed with Long COVID (U09.9) by a multidisciplinary team. All patients are assessed with a battery of questionnaires, physical tests, laboratory tests and radiology. After their first assessment, individuals may have further organ specific work up for diagnosis, such as diagnosis of Postural Orthostatic Tachycardia Syndrome (POTS).

Once the patient has been diagnosed with Long COVID, they will be informed and asked to participate in the trial. No study specific procedures will take place before an informed consent form (ICF) has been signed. The patients will be included once they fulfil the inclusion criteria and exhibit none of the exclusion criteria. Some study specific procedures will be performed before inclusion. Eligible subjects will be randomized within two weeks of the planned first treatment. Subjects will be randomized in a 1:1 allocation to HBO2 or placebo (sham treatment). Scheduling of the HBOT will depend on available resources but the first treatment should be given within two weeks after randomization, and a maximum ten treatments should be given within 6 weeks from randomization.

Clinical equipoise: The rationale for 1:1 randomization is that this is a new disease and that it will maximise the statistical power to detect a statistically significant efficacy between treatment groups.

Main efficacy and safety endpoints will be evaluated at three months but the trial will continue for one year after inclusion or until withdrawal. There will also be a four year post-trial follow up of health-economy.

The trial will be conducted in compliance with Good Clinical Practice (GCP), the Declaration of Helsinki and national regulatory requirements.

Conditions

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COVID-19 Post COVID-19 Condition Post COVID-19 Condition, Unspecified Post COVID Condition Post-COVID Syndrome Post-Acute COVID-19 Syndrome

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Randomized, placebo-controlled, double-blind, phase II

Primary Study Purpose

TREATMENT

Blinding Strategy

TRIPLE

Participants Investigators Outcome Assessors

Subjects will be randomized to either active treatment or sham treatment. Assessors will be blinded to treatment group.

Study Groups

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Hyperbaric oxygen treatment

HBO2 240 kPa, 90 min, maximum 10 treatments

Group Type EXPERIMENTAL

Hyperbaric oxygen

Intervention Type DRUG

Hyperbaric oxygen 240 kPa for 90 minutes (with 10 min compression time, 2 air bakes and 10 minutes decompression time).

Sham treatment

Air 134-120 kPa, 90 min, maximum 10 treatments

Group Type PLACEBO_COMPARATOR

Sham treatment

Intervention Type PROCEDURE

Sham treatment 134-120 kPa Air (with 5 min compression time, and 5 min decompression to 120 kPa, two air brakes will be reported to the subjects)

Interventions

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Hyperbaric oxygen

Hyperbaric oxygen 240 kPa for 90 minutes (with 10 min compression time, 2 air bakes and 10 minutes decompression time).

Intervention Type DRUG

Sham treatment

Sham treatment 134-120 kPa Air (with 5 min compression time, and 5 min decompression to 120 kPa, two air brakes will be reported to the subjects)

Intervention Type PROCEDURE

Other Intervention Names

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HBO HBO2 HBOT Placebo

Eligibility Criteria

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Inclusion Criteria

1. Aged 18-60 years
2. Healthy or mild systemic disease (ASA 1-2) prior to COVID-19
3. Symptoms consistent with Long COVID for at least 12 weeks
4. Diagnosed with Long COVID, PACS, PCS (ICD-10 U09.9)
5. Working or studying prior to COVID-19
6. Documented informed consent according to GCP and national regulations

Exclusion Criteria

1. Known pregnancy or positive pregnancy test in women of childbearing age
2. ASA 3 or more from other cause than Long COVID
3. Score above 70 in RAND-36 Role Limitation Physical Health (RP) or Physical Functioning (PF)
4. Diabetes
5. Diagnosed with hypertension prior to COVID-19
6. Contraindication for hyperbaric oxygen treatment according to local guidelines
7. Participation or recent participation in a clinical trial with an investigational product
8. Mental inability, reluctance or language difficulties that result in difficulty understanding the meaning of study participation

Minimum Eligible Age

18 Years

Maximum Eligible Age

60 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Responsible Party

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Anders Kjellberg, MD

ICU Consultant, head of hyperbaric medicine

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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Anders Kjellberg, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Karolinska University Hospital (and Karolinska Insitutet)

Judith Bruchfeld, MD, PhD

Role: STUDY_CHAIR

Karolinska University Hospital (and Karolinska Insitutet)

Malin Nygren-Bonnier, PhD

Role: STUDY_CHAIR

Karolinska University Hospital (and Karolinska Insitutet)

Michael Runold, MD, PhD

Role: STUDY_CHAIR

Karolinska University Hospital (and Karolinska Insitutet)

Marcus Ståhlberg, MD, PhD

Role: STUDY_CHAIR

Karolinska University Hospital (and Karolinska Insitutet)

Peter Lindholm, MD, PhD

Role: STUDY_CHAIR

Karolinska Insitutet

Locations

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Karolinska University Hospital

Stockholm, , Sweden

Site Status

Countries

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Sweden

References

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Venkatesan P. NICE guideline on long COVID. Lancet Respir Med. 2021 Feb;9(2):129. doi: 10.1016/S2213-2600(21)00031-X. Epub 2021 Jan 13. No abstract available.

Reference Type BACKGROUND

PMID: 33453162 (View on PubMed)

Dani M, Dirksen A, Taraborrelli P, Torocastro M, Panagopoulos D, Sutton R, Lim PB. Autonomic dysfunction in 'long COVID': rationale, physiology and management strategies. Clin Med (Lond). 2021 Jan;21(1):e63-e67. doi: 10.7861/clinmed.2020-0896. Epub 2020 Nov 26.

Reference Type BACKGROUND

PMID: 33243837 (View on PubMed)

Kjellberg A, De Maio A, Lindholm P. Can hyperbaric oxygen safely serve as an anti-inflammatory treatment for COVID-19? Med Hypotheses. 2020 Nov;144:110224. doi: 10.1016/j.mehy.2020.110224. Epub 2020 Aug 30.

Reference Type BACKGROUND

PMID: 33254531 (View on PubMed)

Kjellberg A, Abdel-Halim L, Hassler A, El Gharbi S, Al-Ezerjawi S, Bostrom E, Sundberg CJ, Pernow J, Medson K, Kowalski JH, Rodriguez-Wallberg KA, Zheng X, Catrina S, Runold M, Stahlberg M, Bruchfeld J, Nygren-Bonnier M, Lindholm P. Hyperbaric oxygen for treatment of long COVID-19 syndrome (HOT-LoCO): protocol for a randomised, placebo-controlled, double-blind, phase II clinical trial. BMJ Open. 2022 Nov 2;12(11):e061870. doi: 10.1136/bmjopen-2022-061870.

Reference Type BACKGROUND

PMID: 36323462 (View on PubMed)

Kjellberg A, Hassler A, Bostrom E, El Gharbi S, Al-Ezerjawi S, Schening A, Fischer K, Kowalski JH, Rodriguez-Wallberg KA, Bruchfeld J, Stahlberg M, Nygren-Bonnier M, Runold M, Lindholm P. Ten sessions of hyperbaric oxygen versus sham treatment in patients with long covid (HOT-LoCO): a randomised, placebo-controlled, double-blind, phase II trial. BMJ Open. 2025 Apr 14;15(4):e094386. doi: 10.1136/bmjopen-2024-094386.

Reference Type DERIVED

PMID: 40228859 (View on PubMed)

Kjellberg A, Hassler A, Bostrom E, El Gharbi S, Al-Ezerjawi S, Kowalski J, Rodriguez-Wallberg KA, Bruchfeld J, Stahlberg M, Nygren-Bonnier M, Runold M, Lindholm P. Hyperbaric oxygen therapy for long COVID (HOT-LoCO), an interim safety report from a randomised controlled trial. BMC Infect Dis. 2023 Jan 20;23(1):33. doi: 10.1186/s12879-023-08002-8.

Reference Type DERIVED

PMID: 36670365 (View on PubMed)