Safety of Inhaled Hydrogen Gas Mixtures in Healthy Volunteers

Study Overview
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Brief Summary
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Hydrogen gas may decrease the degree or incidence of brain injury following ischemia. The purpose of this study is to determine the safety and tolerability of inhaled hydrogen gas at the dose exposures required for a clinical efficacy study in healthy adult participants. Participants will breathe a gas mixture that contains a low concentration of hydrogen gas in air through a high flow nasal cannula. Investigators will test for any changes in breathing and neurologic status, as well as lab tests during and following the exposure period.

Detailed Description
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Inhaled hydrogen gas (H2) has been shown to have significant protective effects on ischemic organs. Clinical trials abroad have shown promise that treatment of patients suffering from stroke, cardiac arrest, or heart attacks may benefit from inhaling hydrogen gas during the early recovery period. The purpose of this study is to determine the safety and tolerability of inhaled hydrogen gas at the dose exposures required for a clinical efficacy study in healthy adult volunteers. Study design. Eight (8) healthy adult participants will be recruited from the greater Boston area for this study. Consenting participants will be admitted to the hospital and will undergo a series of screens (questionnaires, examination, tests) to ensure suitability to participate. Eligible and consenting participants will then undergo exposure to 2.4% H2 in medical air via high flow nasal cannula for either 24 (n=2), 48 (n=2) or 72 (n=4) hours. Participants will be screened for adverse effects as follows: vital signs every 8 hours, nursing assessment of symptoms (codified based on the National Cancer Institute's Common Terminology Criteria for Adverse Events, CTCAE) every 8 hours, bedside spirometry daily, mini-mental state exam daily, physician physical exam daily, and serum testing (blood count, chemistry, liver and coagulation profile, venous blood gas) following exposure period.

Official Title
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Safety of Inhaled Hydrogen Gas Mixtures in Healthy Volunteers

Conditions
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Healthy

Intervention / Treatment
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* Drug: Hydrogen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 to 35 Able to remain inpatient for duration of admission (24-72 hours) Exclusion Criteria: History of any chronic illness, including respiratory disorders such as asthma, chronic obstructive pulmonary disease, prior acute lung injury or acute respiratory distress syndrome; Inflammatory disorders, such as lupus erythematosus, inflammatory bowel disease; Heritable disorders, such as trisomy 21, cystic fibrosis; Mitochondrial disorders; Currently smoking cigarettes or have a history of smoking cigarettes; The regular use of prescription medications (except for contraceptive medications) within 30 days of enrollment; Any lifetime inpatient hospitalization for respiratory illness; Pregnancy.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Screening
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Hydrogen exposure<br>The first two patients will be exposed to 2.4% hydrogen gas in medical air via HFNC for 24 hours. The second two patients will be exposed to the same gas for 48 hours. The final 4 patients will be exposed to the same gas for 72 hours. | Drug: Hydrogen<br>* Gas exposure for 24, 48 or 72 hours via high flow nasal cannula.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adverse effects/symptoms | Any adverse effects will be codified according the the NCI CTCAE v5.0 | During inhalation exposure | 
| Adverse effects/symptoms | Any adverse effects will be codified according the the NCI CTCAE v5.0 | 2 hours following end of exposure period | 
| Adverse effects/symptoms | Any adverse effects will be codified according the the NCI CTCAE v5.0 | 24 hours following end of exposure period | 
| Adverse effects/symptoms | Any adverse effects will be codified according the the NCI CTCAE v5.0 | 5 days following end of exposure period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mini-mental state exam | Numerical change in mini mental state exam | 1 hour before end of exposure period | 
| Bedside spirometry | FEV1 | 1 hour before end of exposure period | 
| Bedside spirometry | Forced vital capacity | 1 hour before end of exposure period |