Normobaric Oxygen Therapy in Colorectal Cancer Patients (NBO-ONCO)

The Potential of Normobaric Oxygen Therapy to Enhance Erythropoiesis, Reduce Oxidative Stress, and Modulate Immune Function in Colorectal Cancer Patients Undergoing Chemotherapy: Study Protocol for a Prospective, Randomized, Double-Blind, Placebo-Controlled Trial (NBO-ONCO)

Colorectal cancer (CRC) patients undergoing chemotherapy often experience anemia, oxidative stress, and immune suppression, significantly impacting their quality of life and treatment outcomes. Normobaric oxygen (NBO) therapy, which delivers oxygen at atmospheric pressure with elevated oxygen concentration, has shown a potential to enhance erythropoiesis, reduce oxidative stress, and modulate immune function. However, its efficacy in CRC patients remains underexplored. This study aims to evaluate the effects of NBO exposures on (1) supporting erythropoiesis by measuring erythropoietin (EPO) levels and hypoxia-inducible factors (HIF-1α), (2) reducing oxidative stress and improving stress and emotional well-being, and (3) modulating immune function by assessing cytokine profiles. Secondary objectives include assessing the impact of NBO on patient-reported outcome measures (PROMs) such as stress, anxiety, depression, and quality of life. This is a prospective, randomized, double-blind, placebo-controlled clinical trial. A total of 254 CRC patients undergoing chemotherapy will be randomized 1:1 to receive either active NBO therapy (n=127) or placebo NBO therapy (n=127). The intervention consists of 10 NBO sessions over five weeks. Primary outcomes include biomarkers of erythropoiesis, oxidative stress, and immune response. Secondary outcomes assess quality of life and psychological well-being. Data will be collected at baseline, mid-intervention, post-intervention, and during two follow-up visits (3- and 6-months post-intervention). The study hypothesizes that NBO therapy will improve erythropoiesis, reduce oxidative stress, and enhance immune function in CRC patients, leading to improved quality of life and clinical outcomes. Findings from this trial may establish NBO as a novel supportive therapy for CRC patients undergoing chemotherapy.

Study Overview

Status

Not yet recruiting

Detailed Description

The intervention will involve NBO as a supportive treatment for CRC patients undergoing chemotherapy. The NBO protocol consists of regular sessions in a normobaric chamber where patients are exposed to controlled oxygen levels aimed at reducing ox-idative stress, supporting erythropoiesis, and modulating immune function. Patients in the CRC group will undergo 10 NBO sessions across five weeks, with two sessions weekly.

Patient's exposure to NBO conditions in group 1 (aNBO) including: oxygen levels of 32-40% (compared to about 21% in the atmosphere), pressure maintained at 1,500 hPa (about 1,000 hPa outside), carbon dioxide levels between 0.7-1.9% (compared to 0.03% in the atmosphere, and hydrogen levels between 0.5-1% (which is 10 to 20 thousand times higher than in the atmosphere). Exposure time in the NBO chamber will be the standard 2 hours with an additional 20 minutes for preparation and adaptation and 10 minutes for the finalization and decompression period.

Patients' exposure to atmospheric conditions in the same NBO chamber (without normobaric conditions to provide sham-placebo intervention) in group 2 (pNBO): oxygen levels about 21%, pressure maintained at about 1,000 hPa, carbon dioxide levels about o 0.03%, and hydrogen levels about 0.00005% (0.5 parts per million, like in the atmos-phere). The primary comparator in this study is the placebo NBO group (CRC patients; n=127) for CRC patients, which serves to differentiate the specific effects of active NBO from the natural course of treatment without enhanced oxygen exposure.

The patient assessment scheme contains six visits from V0 to V5 with subsequent analytical packages with detailed explanation in 2.8. section. The patient assessment schedule consists of six visits, from V0 to V5, each including specific evaluations and interventions. The study begins with V0 (prequalification/screening), where patient consent is obtained, medical history is collected, and baseline data are recorded. V1 (randomization and pre-test visit) involves the initial assessments, including anemia, stress, immune, genetic markers, and patient-reported outcomes (PROMs). Following this, the first phase of the NBO intervention (sessions 1-5) takes place over five weeks. At V2 (midpoint evaluation), the same set of assessments is repeated to track progress, followed by the second phase of the NBO intervention (sessions 6-10) conducted over the next five weeks. V3 (finalization and post-test visit) marks the completion of the intervention, with a final round of primary and secondary outcome assessments. The study then proceeds with two follow-up visits: V4 (3-months post-NBO) and V5 (6-months post-NBO), where anemia, stress, immune, genetic markers, and PROMs are reassessed to evaluate the long-term effects of the intervention.

Study Type

Interventional

Enrollment (Estimated)

254

Phase

  • 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 Locations

      • Wroclaw, Poland, 50-981
        • 4th Military Clinical Hospital
        • Contact:
        • Contact:
          • Jacek Polański Dr, PhD
        • Contact:
          • Edyta Pawlak Prof., PhD
        • Contact:
          • Beata Freier MD, PhD

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

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • age between 18 and 80 years (participants must be adults)
  • diagnosed with CRC (stage II-IV, scheduled for standard chemotherapy (for study and control groups)
  • baseline hemoglobin levels above 10 g/dL
  • no concurrent hematologic malignancies
  • eastern Cooperative Oncology Group (ECOG) performance status of 0-2 (ensuring participants are ambulatory and capable of self-care)
  • life expectancy of at least 12 months (participants are expected to survive the duration of the study)
  • ability and willingness to comply with all study procedures and schedules (including NBO therapy sessions and follow-up visits)
  • adequate organ function as determined by laboratory tests (liver function tests - ALT, AST), renal function tests (serum creatinine, eGFR)
  • women of childbearing potential must have a negative pregnancy test prior to enrollment and agree to use effective contraception during the study (to ensure safety for potential pregnancies)
  • written informed consent obtained prior to any study-related procedures (participants must understand and agree to all aspects of the study).

Exclusion Criteria:

  • age under 18 years or over 80 years
  • severe cardiovascular or respiratory conditions (e.g., unstable angina, recent myocardial infarction, advanced COPD)
  • severe anemia (hemoglobin <10 g/dL) or any hemolytic disorder that could confound study outcomes
  • uncontrolled diabetes mellitus (e.g., HbA1c >8.0% or poor glycemic control requiring frequent hospitalizations)
  • pregnancy or breastfeeding
  • severe infection or immunocompromised status unrelated to cancer (e.g., advanced HIV infection)
  • current psychiatric or neurological disorders that could interfere with study participation
  • participation in other investigational therapies within the last 30 days; (9) lack of written informed consent for study participation
  • autoimmune or inflammatory conditions (e.g., lupus, rheumatoid arthritis on immunosuppressive therapy) that significantly alter immune responses
  • presence of any contraindication for NBO therapy (e.g., active bleeding, acute infections, inflammation of the optic nerve, epilepsy or seizures, uncontrolled diabetes as noted above, pneumothorax, emphysema, electronic implants).

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: Supportive Care
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: active NBO therapy (n=127)
Patient's exposure to NBO conditions in group 1 (aNBO)
Patient's exposure to NBO conditions in group 1 (aNBO) including: oxygen levels of 32-40% (compared to about 21% in the atmosphere), pressure maintained at 1,500 hPa (about 1,000 hPa outside), carbon dioxide levels between 0.7-1.9% (compared to 0.03% in the atmosphere, and hydrogen levels between 0.5-1% (which is 10 to 20 thousand times higher than in the atmosphere). Exposure time in the NBO chamber will be the standard 2 hours with an additional 20 minutes for preparation and adaptation and 10 minutes for finalization and the decompression period.
Patients' exposure to atmospheric conditions in the same NBO chamber (without normobaric conditions to provide placebo intervention as the study comparator) in group 2 (pNBO): oxygen levels about 21%, pressure maintained at about 1,000 hPa, carbon dioxide levels about o 0.03%, and hydrogen levels about 0.00005% (0.5 parts per million, like in the atmos-phere).
Placebo Comparator: placebo NBO therapy (n=127)
Patients' exposure to atmospheric conditions in the same NBO chamber without normobaric conditions in group 2 (pNBO)
Patient's exposure to NBO conditions in group 1 (aNBO) including: oxygen levels of 32-40% (compared to about 21% in the atmosphere), pressure maintained at 1,500 hPa (about 1,000 hPa outside), carbon dioxide levels between 0.7-1.9% (compared to 0.03% in the atmosphere, and hydrogen levels between 0.5-1% (which is 10 to 20 thousand times higher than in the atmosphere). Exposure time in the NBO chamber will be the standard 2 hours with an additional 20 minutes for preparation and adaptation and 10 minutes for finalization and the decompression period.
Patients' exposure to atmospheric conditions in the same NBO chamber (without normobaric conditions to provide placebo intervention as the study comparator) in group 2 (pNBO): oxygen levels about 21%, pressure maintained at about 1,000 hPa, carbon dioxide levels about o 0.03%, and hydrogen levels about 0.00005% (0.5 parts per million, like in the atmos-phere).

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Erythropoietin (EPO) concentration
Time Frame: From enrollment to the end of 6th month follow-up
Erythropoietin (EPO) concentration [mU/mL] will be measured using a quantitative immunoassay (ELISA) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Hypoxia-inducible factor-1α (HIF-1α)
Time Frame: From enrollment to the end of 6th month follow-up
Hypoxia-inducible factor-1α (HIF-1α) [ng/mL] will be measured using a quantitative immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Reticulocyte count
Time Frame: From enrollment to the end of 6th month follow-up
Reticulocyte count [% of total red blood cells] will be measured using an automated hematology analyzer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Red blood cell (RBC)
Time Frame: From enrollment to the end of 6th month follow-up
Red blood cell (RBC) count [10¹² cells/L] will be measured using 5-part differential blood morphology on an automated hematology analyzer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Hemoglobin concentration (HGB)
Time Frame: From enrollment to the end of 6th month follow-up
Hemoglobin concentration (HGB) [g/dL] will be measured using an automated hematology analyzer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Hematocrit
Time Frame: From enrollment to the end of 6th month follow-up
Hematocrit [%] will be measured using an automated hematology analyzer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Serum creatinine
Time Frame: From enrollment to the end of 6th month follow-up
Serum creatinine [µmol/L] will be measured using an enzymatic assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Estimated glomerular filtration rate (eGFR)
Time Frame: From enrollment to the end of 6th month follow-up
Estimated glomerular filtration rate (eGFR) [mL/min/1.73 m²] will be calculated using the CKD-EPI equation at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Alanine aminotransferase (ALT)
Time Frame: From enrollment to the end of 6th month follow-up
Alanine aminotransferase (ALT) [IU/L] will be measured using an enzymatic assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Aspartate aminotransferase (AST)
Time Frame: From enrollment to the end of 6th month follow-up
Aspartate aminotransferase (AST) [IU/L] will be measured using an enzymatic assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Fasting glucose
Time Frame: From enrollment to the end of 6th month follow-up
Fasting glucose [mmol/L] will be measured using a hexokinase assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Fasting insulin
Time Frame: From enrollment to the end of 6th month follow-up
Fasting insulin [µU/mL] will be measured using an immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Lipid profile
Time Frame: From enrollment to the end of 6th month follow-up
Lipid profile (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides) [mmol/L] will be measured using enzymatic/colorimetric assays at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Iron metabolism (serum iron, total iron-binding capacity [TIBC]
Time Frame: From enrollment to the end of 6th month follow-up
Iron metabolism (serum iron, total iron-binding capacity [TIBC] [µmol/L], ferritin [ng/mL], vitamin B₁₂ [pg/mL]) will be measured using immunoassays at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Serum albumin
Time Frame: From enrollment to the end of 6th month follow-up
Serum albumin [g/L] will be measured using a bromcresol green assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
C-reactive protein (CRP)
Time Frame: From enrollment to the end of 6th month follow-up
C-reactive protein (CRP) [mg/L] will be measured using a high-sensitivity immunoturbidimetric assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Reactive oxygen species (ROS) level
Time Frame: From enrollment to the end of 6th month follow-up]
Reactive oxygen species (ROS) level [relative fluorescence units] will be measured using a chemiluminescence assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up]
Serum cortisol
Time Frame: From enrollment to the end of 6th month follow-up
Serum cortisol [µg/dL] will be measured using a high-sensitivity immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Gamma-aminobutyric acid (GABA)
Time Frame: From enrollment to the end of 6th month follow-up
Gamma-aminobutyric acid (GABA) [µmol/L] will be measured using an enzyme-linked immunosorbent assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Dopamine
Time Frame: From enrollment to the end of 6th month follow-up
Dopamine [ng/mL] will be measured using a competitive immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Serotonin
Time Frame: From enrollment to the end of 6th month follow-up
Serotonin [ng/mL] will be measured using a competitive immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Fibrinogen
Time Frame: From enrollment to the end of 6th month follow-up
Fibrinogen [g/L] will be measured using the Clauss clotting assay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Glycated hemoglobin (HbA₁c)
Time Frame: From enrollment to the end of 6th month follow-up
Glycated hemoglobin (HbA₁c) [%] will be measured using high-performance liquid chromatography at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Dehydroepiandrosterone-sulfate (DHEA-S)
Time Frame: From enrollment to the end of 6th month follow-up
Dehydroepiandrosterone-sulfate (DHEA-S) [µg/dL] will be measured using an immunoassay at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Systolic blood pressure (SBP)
Time Frame: From enrollment to the end of 6th month follow-up
Systolic blood pressure (SBP) [mmHg] will be measured using an automated sphygmomanometer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Diastolic blood pressure (DBP)
Time Frame: From enrollment to the end of 6th month follow-up
Diastolic blood pressure (DBP) [mmHg] will be measured using an automated sphygmomanometer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Heart rate (HR)
Time Frame: From enrollment to the end of 6th month follow-up
Heart rate (HR) [beats per minute] will be measured using an automated sphygmomanometer at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Body mass index (BMI)
Time Frame: From enrollment to the end of 6th month follow-up
Body mass index (BMI) [kg/m²] will be calculated from measured weight and height at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Body surface area (BSA)
Time Frame: From enrollment to the end of 6th month follow-up
Body surface area (BSA) [m²] will be calculated using the Mosteller formula from measured weight and height at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Waist-to-hip ratio (WHR)
Time Frame: From enrollment to the end of 6th month follow-up
Waist-to-hip ratio (WHR) [ratio] will be calculated from measured waist and hip circumferences at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Tumor necrosis factor-α (TNF-α)
Time Frame: From enrollment to the end of 6th month follow-up
Tumor necrosis factor-α (TNF-α) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Interleukin-1β (IL-1β)
Time Frame: From enrollment to the end of 6th month follow-up
Interleukin-1β (IL-1β) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Interleukin-6 (IL-6)
Time Frame: From enrollment to the end of 6th month follow-up
Interleukin-6 (IL-6) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Interleukin-10 (IL-10)
Time Frame: From enrollment to the end of 6th month follow-up
Interleukin-10 (IL-10) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Monocyte chemoattractant protein-1 (MCP-1/CCL2)
Time Frame: From enrollment to the end of 6th month follow-up
Monocyte chemoattractant protein-1 (MCP-1/CCL2) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Macrophage inflammatory protein-1α (MIP-1α/CCL3)
Time Frame: From enrollment to the end of 6th month follow-up
Macrophage inflammatory protein-1α (MIP-1α/CCL3) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Macrophage inflammatory protein-1β (MIP-1β/CCL4)
Time Frame: From enrollment to the end of 6th month follow-up
Macrophage inflammatory protein-1β (MIP-1β/CCL4) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Vascular endothelial growth factor A (VEGF-A)
Time Frame: From enrollment to the end of 6th month follow-up
Vascular endothelial growth factor A (VEGF-A) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Platelet-derived growth factor-BB (PDGF-BB)
Time Frame: From enrollment to the end of 6th month follow-up
Platelet-derived growth factor-BB (PDGF-BB) [pg/mL] will be measured using a multiplex immunoassay (Luminex) at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Stress level (self-assessment)
Time Frame: From enrollment to the end of 6th month follow-up
The Perceived Stress Questionnaire (PSQ-30) is a 30-item self-report instrument designed to assess perceived stress over the previous month. Each item is rated on a 4-point Likert scale (1 = "almost never" to 4 = "usually"), yielding a raw score that can range from 30 (minimum) to 120 (maximum). Higher raw scores indicate greater perceived stress (worse outcome). The PSQ-30 will be administered at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Anxiety and depression levels (self-assessment)
Time Frame: From enrollment to the end of 6th month follow-up
The Hospital Anxiety and Depression Scale (HADS) is a 14-item self-report questionnaire comprising two subscales: HADS-Anxiety (HADS-A) and HADS-Depression (HADS-D). Each subscale contains 7 items scored on a 4-point Likert scale (0 = "not at all" to 3 = "very often"), yielding subscale scores from 0 (minimum) to 21 (maximum). Higher scores indicate greater symptom severity (worse outcome). The HADS total score (sum of HADS-A and HADS-D) ranges from 0 to 42. The HADS will be administered at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up
Quality of live level (self-assessment)
Time Frame: From enrollment to the end of 6th month follow-up
EuroQol Five-Dimension Five-Level questionnaire (EQ-5D-5L) index score [-0.59 to 1.00; higher = better health] will be derived from five domains-mobility, self-care, usual activities, pain/discomfort, and anxiety/depression-each rated on a 5-point scale (1 = no problems to 5 = extreme problems). Health states will be converted to a single index value using the Polish EQ-5D-5L value set. The EQ-5D-5L will be administered at V1, V2, V3, V4, and V5.
From enrollment to the end of 6th month follow-up

Collaborators and Investigators

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

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 (Estimated)

November 1, 2025

Primary Completion (Estimated)

November 1, 2027

Study Completion (Estimated)

November 1, 2028

Study Registration Dates

First Submitted

April 10, 2025

First Submitted That Met QC Criteria

April 23, 2025

First Posted (Actual)

April 27, 2025

Study Record Updates

Last Update Posted (Actual)

April 27, 2025

Last Update Submitted That Met QC Criteria

April 23, 2025

Last Verified

April 1, 2025

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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.

Subscribe