Blood Markers Predict Effect of Normobaric Hypoxia at Rest and During Exercise in Patients With Pulmonary Hypertension (HEXABM)
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ClinicalTrials.gov Identifier: NCT04715113 |
Recruitment Status :
Recruiting
First Posted : January 20, 2021
Last Update Posted : May 20, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hypertension, Pulmonary | Other: Normobaric hypoxia (FiO2 15%) Other: Placebo-ambient air (FiO2 21%) Other: Normobaric hypoxia (FiO2 15%) under Sildenafil Other: Placebo-ambient air (FiO2 21%) under Sildenafil | Not Applicable |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 24 participants |
Allocation: | Randomized |
Intervention Model: | Crossover Assignment |
Masking: | Single (Participant) |
Primary Purpose: | Treatment |
Official Title: | Hemodynamic Effects of Acute Normobaric Hypoxia During Exercise in Patients With Pulmonary Hypertension: Single-center Randomized Controlled Trial |
Actual Study Start Date : | February 1, 2021 |
Estimated Primary Completion Date : | December 31, 2023 |
Estimated Study Completion Date : | December 31, 2024 |

Arm | Intervention/treatment |
---|---|
Experimental: Normobaric hypoxia (FiO2 15%)
Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
|
Other: Normobaric hypoxia (FiO2 15%)
Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise. |
Sham Comparator: Placebo-ambient air (FiO2 21%)
Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
|
Other: Placebo-ambient air (FiO2 21%)
Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise. |
Experimental: Normobaric hypoxia (FiO2 15%) under Sildenafil
Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
|
Other: Normobaric hypoxia (FiO2 15%) under Sildenafil
Inhalation of deoxygenated air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise under Sildenafil. |
Active Comparator: Placebo-ambient air (FiO2 21%) under Sildenafil
Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise.
|
Other: Placebo-ambient air (FiO2 21%) under Sildenafil
Inhalation of room air through an altitude simulator ("Altitrainer"), for approx. 1/2 hour given by a facemask, first at rest and then during exercise under Sildenafil. |
- Serum levels of ferritin [ Time Frame: Baseline ]Analyis of serum levels of ferritin
- Serum levels of transferrin [ Time Frame: Baseline ]Analyis of serum levels of transferrin
- Serum levels of total iron [ Time Frame: Baseline ]Analysis of serum levels of total iron
- Serum levels of erythropoietin [ Time Frame: Baseline ]Analysis of serum levels of erythropoietin
- Serum levels of Erythroferrone [ Time Frame: Baseline ]Analysis of serum levels of erythroferrone
- Serum levels of hepcidin [ Time Frame: Baseline ]Analysis of serum levels of hepcidin
- micro-RNA levels [ Time Frame: Baseline ]Analysis of micro-RNA levels

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Informed consent as documented by signature (Appendix Informed Consent Form)
- PH class I (PAH) or IV (CTEPH) diagnosed according to guidelines: mean pulmonary artery pressure >20 mmHg, pulmonary vascular resistance ≥3 wood units, pulmonary arterial wedge pressure ≤15 mmHg during baseline measures at the diagnostic right-heart catheterization
Exclusion Criteria:
- resting partial pressure of oxygen <8 kilopascal at Zürich altitude on ambient air
- exposure to an altitude >1000 m for ≥3 nights during the last 2 weeks before the study
- inability to follow the procedures of the study
- patients who take nitrates
- other clinically significant concomitant end-stage disease (e.g., renal failure, hepatic dysfunction)

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04715113
Contact: Silvia Ulrich, Prof. Dr. | +41442552220 | silvia.ulrich@usz.ch | |
Contact: Saxer Stéphanie, Dr. | +41442552248 | stephanie.saxer@usz.ch |
Switzerland | |
University Hospital of Zurich | Recruiting |
Zurich, Switzerland, 8091 | |
Contact: Silvia o Ulrich, Prof. Dr. +41442552220 silvia.ulrich@usz.ch |
Principal Investigator: | Silvia Ulrich, Prof. Dr. | UniversityHospital Zurich, Department of Pulmonology |
Responsible Party: | University of Zurich |
ClinicalTrials.gov Identifier: | NCT04715113 |
Other Study ID Numbers: |
2020-02163_A4 |
First Posted: | January 20, 2021 Key Record Dates |
Last Update Posted: | May 20, 2022 |
Last Verified: | May 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | We will share individual participant data after publication of the manuscript. The decision about the platform is ongoing. |
Time Frame: | After publication of the manuscript |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
hypoxia exercise blood markers |
Hypertension, Pulmonary Hypertension Hypoxia Vascular Diseases Cardiovascular Diseases Lung Diseases Respiratory Tract Diseases Signs and Symptoms, Respiratory |
Sildenafil Citrate Vasodilator Agents Phosphodiesterase 5 Inhibitors Phosphodiesterase Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Urological Agents |