Hyperbaric Oxygen Therapy for Ulcerative Colitis (HBOT-UC) (HBOT-UC)

January 6, 2026 updated by: Lauren C Balmert, Northwestern University

Hyperbaric Oxygen Therapy for Ulcerative Colitis Patients Hospitalized for Moderate to Severe Flares: A Multi-Center, Randomized, Double-Blind, Sham-Controlled Trial

Chronic intestinal hypoxia and accompanying mucosal inflammation is a hallmark of ulcerative colitis (UC). Hyperbaric oxygen therapy (HBOT) involves breathing 100% oxygen under increased atmospheric pressure to increase tissue oxygenation. Two small prospective randomized controlled trials have demonstrated that the delivery of HBOT to UC patients hospitalized for acute moderate to severe flares results in improved remission rates and avoidance of in-hospital progression to biologics, small molecules, or colectomy. In this larger trial the study aims to confirm the treatment benefits of HBOT for hospitalized UC patients and study the immune-microbe mechanisms underpinning treatment response.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
126

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Alabama
      • Birmingham, Alabama, United States, 35233
        • Recruiting
        • University of Alabama Medicine
        • Contact:
    • California
      • Los Angeles, California, United States, 90024
    • Florida
    • Illinois
      • Lake Forest, Illinois, United States, 60045
    • Kentucky
      • Louisville, Kentucky, United States, 40202
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
    • Minnesota
      • Rochester, Minnesota, United States, 55905
    • New Hampshire
    • New York
      • New York, New York, United States, 10065
        • Active, not recruiting
        • Cornell University Medical Center
      • Syracuse, New York, United States, 13210
        • Recruiting
        • State University of New York Upstate Medical University
        • Contact:
    • Pennsylvania
      • Pittsburgh, Pennsylvania, United States, 15213
        • Recruiting
        • University of Pittsburgh Medical Center
        • Contact:
      • Pittsburgh, Pennsylvania, United States, 15090

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Participants with known or newly diagnosed UC who require hospitalization for an acute moderate to severe flare
  • Age 18-85
  • Able to fully participate in all aspects of the trial
  • Consented and able to receive first HBOT session within first 48 hours of initiation of intravenous steroids
  • Agreement to not participate in another trial for the duration of the active intervention period

Exclusion Criteria:

  • Received hyperbaric oxygen therapy either as part of standard of care or through a clinical trial prior to enrollment
  • Complication requiring urgent surgical intervention
  • Requirement for new start of a biologic or small molecule during the hospitalization prior to randomization and/or anticipated requirement for rescue medical or surgical therapy within 48 hours of randomization
  • Toxic megacolon
  • Inability to receive intravenous steroids
  • Historically failed or been exposed to 4 or more classes of advanced therapeutic options
  • Known or suspected diagnosis of Crohn's colitis, indeterminate colitis, ischemic colitis, radiation colitis, diverticular disease associated with colitis, microscopic colitis or infectious colitis
  • Received any investigational drug within 30 days
  • Clinically significant cardiac, renal, neurological, endocrine, respiratory or hepatic impairment that increases the risk for HBOT toxicity
  • Women who are pregnant or nursing
  • Unwillingness to complete course of HBOT

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Hyperbaric Oxygen Therapy
Participants enrolled in the active intervention group receiving HBOT will undergo compression to 2.4 Atmospheres Absolute (ATA; 100% O2) for 90 minutes with two 5-10 minute "air breaks" (breathing room air at the 2.4 ATA) during the session. This is done once a day for 5 days.
Device: Hyperbaric Oxygen Therapy
Participants enrolled in the active intervention group receiving HBOT will undergo compression to 2.4 Atmospheres Absolute (ATA; 100% O2) for 90 minutes with two 5-10 minute "air breaks" (breathing room air at the 2.4 ATA) during the session. This is done once a day for 5 days.
Sham Comparator: Sham Hyperbaric Air
This control arm will undergo compression to 1.34 ATA for monoplace chambers and 2.4 ATA for multiplace chambers for the full 90-minute session but 21% oxygen instead of 100% oxygen being administered. These participants will also have two 5-10 minute "air breaks" to mimic the treatment protocol. Multiplace sham sessions will have modified air breaks to avoid decompression sickness. This will happen once a day for 5 days.
Other: Sham Hyperbaric Air
This control arm will undergo compression to 1.34 ATA for monoplace chambers and 2.4 ATA for multiplace chambers for the full 90-minute session but 21% oxygen instead of 100% oxygen being administered. These participants will also have two 5-10 minute "air breaks" to mimic the treatment protocol. Multiplace sham sessions will have modified air breaks to avoid decompression sickness. This will happen once a day for 5 days.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Clinical response defined as complete resolution of rectal bleeding and improvement in stool frequency, without need for in-hospital biologics, small molecules, or colectomy by study day 5
Time Frame: Day 5
Proportion of participants achieving clinical response as measured by complete resolution of rectal bleeding (Mayo rectal bleeding sub-score of 0) and improvement in stool frequency (at least 1 point reduction in Mayo stool frequency sub-score), without the need for in-hospital biologics, small molecules, or colectomy, by study day 5.
Day 5

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Serious Infections or Serious Adverse Events
Time Frame: Day 5
Proportion of participants experiencing any serious infections or serious adverse events during intervention period
Day 5
Clinical Response
Time Frame: Day 3
Sum of Mayo rectal bleeding and stool frequency sub-scores (Key secondary endpoint)
Day 3
Change in inflammation, as measured by C-reactive protein
Time Frame: Day 3
Change in inflammation, as measured by C-reactive protein (Key secondary endpoint)
Day 3
Endoscopic response
Time Frame: Day 5
Ulcerative Colitis Endoscopic Index of Severity (UCEIS) (Key secondary endpoint)
Day 5
Steroid-free, colectomy-free, clinical remission
Time Frame: Day 90
Proportion of participants steroid-free, colectomy-free, and with clinical remission (Full Mayo ≤ 2, with no sub-score > 1)
Day 90
Endoscopic Improvement
Time Frame: Day 90
Proportion of participants achieving endoscopic improvement (Mayo endoscopic sub-score of 0 or 1)
Day 90
Endoscopic Remission
Time Frame: Day 90
Proportion of participants achieving Endoscopic remission (Mayo endoscopic sub-score of 0)
Day 90
Mucosal Healing
Time Frame: Day 90
Proportion of participants achieving Mucosal Healing (Endoscopic sub-score 0 or 1 + Geboes histology score ≤ 2)
Day 90
Clinical Remission
Time Frame: Day 5
Proportion of participants achieving clinical remission (Full Mayo ≤ 2, with no sub-score > 1)
Day 5
Colectomy
Time Frame: Day 90; 12 month
Proportion of participants requiring colectomy
Day 90; 12 month
Re-hospitalization for ulcerative colitis flare
Time Frame: 12 months
Proportion of participants with re-hospitalization during the follow-up period for ulcerative colitis flare
12 months
Numeric Urgency Rating Score
Time Frame: Day 3
Score ranges from 0-10 ; higher scores are worse
Day 3

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Northwestern University

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Lauren Balmert Bonner, PhD, Northwestern University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 9, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
September 1, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
September 1, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 1, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 9, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 14, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 8, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 6, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • HBOT-UC
  • 1U01DK134321 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Dataset with National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Repository.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • ICF

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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