Airway InflammationSmokeysalNCT03851406
Woodsmoke Particulate + Hypertonic Saline
A study testing 5% Hypertonic Saline and No treatment in people with Airway Inflammation, run by University of North Carolina, Chapel Hill at 1 site in United States.
Trial summary
Deployment of military personnel has been associated with increased respiratory illness likely due, in part, to inhalation of unusual particulate matter (PM), such as from burn pits. Inflammation is a key initial response to inhaled particulates. Read more about this study
- Who is it for?
- Ages 18 to 45 yearsHealthy volunteers can take part
- Conditions the study is for
- Airway Inflammation
- What is being tested?
- 5% Hypertonic Saline and No treatment
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 9 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Aug 2019to 12 Sep 2024
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age 18-45 years, inclusive, of both genders
- Negative pregnancy test for females who are not s/p hysterectomy with oophorectomy
- No history of episodic wheezing, chest tightness, or shortness of breath consistent with asthma, or physician-diagnosed asthma.
- forced expiratory volume at one second (FEV1) of at least 80% of predicted and FEV1/forced vital capacity (FVC) ratio of >0.70.
- Oxygen saturation of >93%
- Ability to provide an induced sputum sample.
- Subject must demonstrate a >10% increase in sputum %PMNs 6 hours following inhaled WSP exposure, when compared to baseline sputum (to be completed in a separate protocol #15-1775).
- Proof of vaccination to SARS-CoV-2 based on public health guidelines at time of inclusion
Who cannot join
- Clinical contraindications:
- Any chronic medical condition considered by the PI as a contraindication to the exposure study including significant cardiovascular disease, diabetes, chronic renal disease, chronic thyroid disease, history of chronic infections/immunodeficiency.
- Viral upper respiratory tract infection within 4 weeks of challenge.
- Any acute infection requiring antibiotics within 4 weeks of exposure or fever of unknown origin within 4 weeks of challenge.
- Abnormal physical findings at the baseline visit, including but not limited to abnormalities on auscultation, temperature of 37.8° C, Systolic BP > 150mm Hg or < 85 mm Hg; or Diastolic BP > 90 mm Hg or < 50 mm Hg, or pulse oximetry saturation reading less than 93%.
- Physician diagnosis of asthma
Show all 18Show fewer
- If there is a history of allergic rhinitis, subjects must be asymptomatic of allergic rhinitis at the time of study enrollment.
- Mental illness or history of drug or alcohol abuse that, in the opinion of the investigator, would interfere with the participant's ability to comply with study requirements.
- Medications which may impact the results of the WSP exposure, interfere with any other medications potentially used in the study (to include steroids, beta antagonists, non-steroidal anti-inflammatory agents)
- Cigarette smoking > 1 pack per month
- Unwillingness to use reliable contraception if sexually active (IUD, birth control pills/patch, condoms).
- Use of immunosuppressive or anticoagulant medications including routine use of NSAIDS. Oral contraceptives are acceptable, as are antidepressants and other medications may be permitted if, in the opinion of the investigator, the medication will not interfere with the study procedures or compromise safety and if the dosage has been stable for 1 month.
- Orthopedic injuries or impediments that would preclude bicycle or treadmill exercise.
- Inability to avoid NSAIDS, Multivitamins, Vitamin C or E or herbal supplements.
- Allergy/sensitivity to study drugs or their formulations
- Positive COVID-19 test in the past 90 days.
- Pregnant/lactating women and children (< 18 years as this is age of majority in North Carolina) will also be excluded since the risks associated with WSP exposure to the fetus or child, respectively, are unknown and cannot be justified for this non-therapeutic protocol. Individuals over 45 years of age will not be included due to the increased possibility of co-morbidities and need for prohibited medications.
- Inability or unwillingness of a participant to give written informed consent
Trial locations and contacts
1 site in 1 country.
United States1 site
Center for Environmental Medicine, Asthma and Lung Biology at UNC Chapel Hill
Chapel Hill, North Carolina, 27599
About this study
Official title: Phase I/II Randomized Cross-over Study of Hypertonic Saline on Airway Inflammatory Response to Inhaled Wood Smoke
Deployment of military personnel has been associated with increased respiratory illness likely due, in part, to inhalation of unusual particulate matter (PM), such as from burn pits. Inflammation is a key initial response to inhaled particulates. The investigator has developed a protocol using inhaled wood smoke particles (WSP) as a way to study PM-induced airway inflammation. Exposure to wood smoke particles causes symptoms, even in healthy people, such as eye irritation, cough, shortness of breath, and increased mucous production. The purpose of this research study is to see if a single treatment of inhaled hypertonic saline (HS) can diminish this PM-induced airway inflammation by rapidly clearing the WSP inhaled particles from airway surfaces. The exposure will be 500 ug/m³ of WSP for 2 hours, with intermittent exercise on a bicycle and rest. The wood is burned in a typical wood stove and piped into the chamber.
Read the detailed description
Military deployment is associated with exposure to novel particulate matter (PM), such as from burn pits, aeroallergens, and increased cigarette consumption. War fighters exposed to these inhalational exposures exhibit immediate and chronic respiratory morbidity. For example, military service personnel surveyed in both the Republic of Korea (ROK) and Kabul, Afghanistan reported a general increase in respiratory morbidity, including asthma and chronic bronchitis, associated with their deployment. Air contaminants in the ROK were characterized by elevated levels of both PM 0.5-2.5 and PM 2.5-10. Similarly, exposures in Kabul were characterized by multiple airborne PM exposures, including those from burn pits. Burn pit PM includes metals, bioaerosols, organic by-products, and biomass combustion particles. These findings indicate that inhaled PM is a likely cause of respiratory morbidity in the field.
Inflammation is a key initial response to inhaled particulates. Wood smoke particles (WSP) serve as a model agent to study PM-induced bronchitis. WSP inhalation generates reactive oxidant (and nitrosative) species which cause local injury of airway epithelial cells and release of damage-associated molecular patterns (DAMPs) that activate toll-like receptors (TLR) and interleukin 1 (IL-1)-mediated innate immune responses by resident airway macrophages. Contamination of PM with bioaerosols, which contain lipopolysaccharide (LPS), also activates innate immune responses through toll-like receptor 4 (TLR4) activation of resident airway macrophages. These complementary processes result in recruitment of neutrophils (PMN), which mediate luminal airway inflammation with release of toxic mediators such as neutrophil elastase and myeloperoxidase that promote acute and chronic bronchitis.
Therefore, mitigation of PM-induced airway neutrophilic inflammation should be a key focus in order to reduce the respiratory morbidity of military personnel. The investigators have studied a number of pro-inflammatory inhaled agents, such as nebulized LPS, ozone (O3), and WSP, as models of acute neutrophilic bronchitis against which to test a number of therapeutic agents. To this effect, the investigators have reported that inhaled fluticasone inhibits O3-induced and LPS-induced neutrophilic inflammation, and that parenteral anakinra and oral gamma-tocopherol inhibit neutrophilic responses to inhaled LPS. In addition to agents with inherent anti-inflammatory and anti-oxidant properties, rapid clearance of inhaled particles from airway surfaces is a complementary approach to reduce PM-induced airway inflammation. This can be assessed through the measurement of mucociliary clearance (MCC).
MCC is dependent on airway secretory cells and submucosal glands that produce a mucin-rich fluid layer on the airway surface and ciliated cells that hydrate and propel mucus out of the lung and into the upper airway. Rates of MCC are dependent on ciliary beat frequency, hydration, and the rheologic properties of mucus. In vitro studies have demonstrated that HS, through an osmotic effect on airway surfaces, improved hydration and mucus rheologic properties, and accelerated mucus transport rates. In addition, the data over the last 30 years has shown that inhaled hypertonic saline (HS) plus cough is the most effective method for acutely clearing the bronchial airways of inhaled, deposited particles. The combined effect is greater than either HS or cough alone. In the studies of asthmatics, the investigators examined the ability of a single HS treatment with a coached cough maneuver to acutely clear radiolabeled Tc99m sulfur colloid particles from airways following LPS exposure. Following HS inhalation and cough clearance maneuvers developed to recover sputum samples for analysis, the investigators observed a rapid clearance of >50% of the inhaled radiolabelled particles. The investigators hypothesize that if other pro-inflammatory particles (PMs, burn pit particles) were cleared similarly via HS-induced acceleration of MCC shortly after exposure, there would be reductions in acute PM-induced inflammation. Thus, in this study, the investigators will assess the effectiveness of inhaled 5% HS, a dose well tolerated by asthmatics at baseline and after inhaled LPS/allergen challenges for sputum induction, in mitigating WSP-induced airway neutrophilic inflammation in healthy volunteers. Normal saline 0.9% (NS) is not going to be used as a placebo treatment in this study, as inhalation of NS itself impacts the rheologic properties of mucus and MCC and thus would not be a suitable placebo. The investigators will, therefore, compare treatment with 5% HS to no receiving no treatment following WSP exposure.
- Conditions
- Airway Inflammation
- Being tested
- 5% Hypertonic Saline, No treatment
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
5% Hypertonic SalineDevice
Immediately following exit from the wood smoke chamber, participants will inhale 15 mL of 5% Hypertonic Saline for 15 minutes delivered by Pari neb with a coached cough maneuver.
No treatmentOther
No inhaled treatment will be provided immediately following exit from the wood smoke chamber.
| Study group | Role | What they receive |
|---|---|---|
| 5% Hypertonic Saline, then No Inhaled Treatment | Active comparator | Participants will receive 5% Hypertonic Saline following WSP exposure. After a 2-week washout period, participants will receive no treatment following WSP exposure. Receives: Device: 5% Hypertonic Saline; Other: No treatment |
| No Inhaled Treatment, then 5% Hypertonic Saline | Active comparator | Participants will receive no inhaled treatment following WSP exposure. After a 2-week washout period, participants will receive 5% Hypertonic Saline following WSP exposure. Receives: Device: 5% Hypertonic Saline; Other: No treatment |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change From Baseline to 4 Hours in Sputum Percent Neutrophils
Change in sputum percent neutrophils from baseline to 4 hours post WSP exposure
Measured: Baseline, 4 hours post WSP exposure
Change From Baseline to 24 Hours in Sputum Percent Neutrophils
Change in sputum percent neutrophils from baseline to 24 hours post WSP exposure
Measured: Baseline, 24 hours post WSP exposure
Secondary outcomes (7)
Change in Number of Sputum Neutrophils
Neutrophil numbers/mg compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Number of Sputum Eosinophils
Eosinophil numbers/mg compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Percent Sputum Eosinophils
Percent eosinophils compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-1b
Interleukin-1β via the Mesoscale platform (pg/mL) compared at 4 and 24 hours post-WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-6
Interleukin-6 via Mesoscale platform (pg/mL) compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-8
Interleukin-8 via Mesoscale platform (pg/mL) compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Change in Tumor Necrosis Factor Alpha
Tumor Necrosis Factor Alpha via Mesoscale platform (pg/mL) compared at 4 and 24 hours post WSP exposure with respect to Baseline.
Measured: Baseline, 4 and 24 hours post WSP exposure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Feb 2019
- Study start1 Aug 2019
- Primary completion12 Sep 2024
- Study completion12 Sep 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (23)Papers the sponsor has linked to this study.
- Other trials for Airway InflammationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- To determine the efficacy of nebulized 5% hypertonic saline (HS) (v. no treatment) in mitigating wood smoke particulate (WSP)-induced neutrophilic airway inflammation, assessed via sputum %polymorphonuclear leukocytes (PMNs), in healthy adults 4 hours post WSP exposure.
- Masking
- None (open label)
- Enrolment
- 9 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of North Carolina, Chapel Hill
- Sponsor type
- University, hospital or other
- Collaborators
- United States Department of Defense
- Responsible party
- Sponsor
- Investigators
- Terry Noah, M.D, Principal investigator, UNC Chapel Hill
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03851406
- Sponsor's protocol ID
- 18-1895
- Acronym
- Smokeysal
- Status last verified
- Feb 2025
- First submitted
- 20 Feb 2019
- Last updated
- 8 Aug 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Publications
Pugh MJ, Jaramillo CA, Leung KW, Faverio P, Fleming N, Mortensen E, Amuan ME, Wang CP, Eapen B, Restrepo M, Morris MJ. Increasing Prevalence of Chronic Lung Disease in Veterans of the Wars in Iraq and Afghanistan. Mil Med. 2016 May;181(5):476-81. doi: 10.7205/MILMED-D-15-00035.
PubMed 27136656Korzeniewski K, Nitsch-Osuch A, Konior M, Lass A. Respiratory tract infections in the military environment. Respir Physiol Neurobiol. 2015 Apr;209:76-80. doi: 10.1016/j.resp.2014.09.016. Epub 2014 Sep 30.
PubMed 25278277Baird CP. Review of the Institute of Medicine report: long-term health consequences of exposure to burn pits in Iraq and Afghanistan. US Army Med Dep J. 2012 Jul-Sep:43-7. No abstract available.
PubMed 22815164Gomez JC, Yamada M, Martin JR, Dang H, Brickey WJ, Bergmeier W, Dinauer MC, Doerschuk CM. Mechanisms of interferon-gamma production by neutrophils and its function during Streptococcus pneumoniae pneumonia. Am J Respir Cell Mol Biol. 2015 Mar;52(3):349-64. doi: 10.1165/rcmb.2013-0316OC.
PubMed 25100610Barth SK, Dursa EK, Bossarte R, Schneiderman A. Lifetime Prevalence of Respiratory Diseases and Exposures Among Veterans of Operation Enduring Freedom and Operation Iraqi Freedom Veterans: Results From the National Health Study for a New Generation of U.S. Veterans. J Occup Environ Med. 2016 Dec;58(12):1175-1180. doi: 10.1097/JOM.0000000000000885.
PubMed 27930474Szema AM. Occupational Lung Diseases among Soldiers Deployed to Iraq and Afghanistan. Occup Med Health Aff. 2013;1:10.4172/2329-6879.1000117. doi: 10.4172/2329-6879.1000117.
PubMed 24443711Morris MJ, Lucero PF, Zanders TB, Zacher LL. Diagnosis and management of chronic lung disease in deployed military personnel. Ther Adv Respir Dis. 2013 Aug;7(4):235-45. doi: 10.1177/1753465813481022. Epub 2013 Mar 7.
PubMed 23470637Auerbach A, Hernandez ML. The effect of environmental oxidative stress on airway inflammation. Curr Opin Allergy Clin Immunol. 2012 Apr;12(2):133-9. doi: 10.1097/ACI.0b013e32835113d6.
PubMed 22306553Alexis NE, Brickey WJ, Lay JC, Wang Y, Roubey RA, Ting JP, Peden DB. Development of an inhaled endotoxin challenge protocol for characterizing evoked cell surface phenotype and genomic responses of airway cells in allergic individuals. Ann Allergy Asthma Immunol. 2008 Mar;100(3):206-15. doi: 10.1016/S1081-1206(10)60444-9.
PubMed 18426139Hernandez ML, Harris B, Lay JC, Bromberg PA, Diaz-Sanchez D, Devlin RB, Kleeberger SR, Alexis NE, Peden DB. Comparative airway inflammatory response of normal volunteers to ozone and lipopolysaccharide challenge. Inhal Toxicol. 2010 Jul;22(8):648-56. doi: 10.3109/08958371003610966.
PubMed 20540623Hernandez M, Brickey WJ, Alexis NE, Fry RC, Rager JE, Zhou B, Ting JP, Zhou H, Peden DB. Airway cells from atopic asthmatic patients exposed to ozone display an enhanced innate immune gene profile. J Allergy Clin Immunol. 2012 Jan;129(1):259-61.e1-2. doi: 10.1016/j.jaci.2011.11.007.
PubMed 22196529Alexis NE, Peden DB. Blunting airway eosinophilic inflammation results in a decreased airway neutrophil response to inhaled LPS in patients with atopic asthma: a role for CD14. J Allergy Clin Immunol. 2001 Oct;108(4):577-80. doi: 10.1067/mai.2001.118511.
PubMed 11590384Hernandez ML, Mills K, Almond M, Todoric K, Aleman MM, Zhang H, Zhou H, Peden DB. IL-1 receptor antagonist reduces endotoxin-induced airway inflammation in healthy volunteers. J Allergy Clin Immunol. 2015 Feb;135(2):379-85. doi: 10.1016/j.jaci.2014.07.039. Epub 2014 Sep 5.
PubMed 25195169Hernandez ML, Wagner JG, Kala A, Mills K, Wells HB, Alexis NE, Lay JC, Jiang Q, Zhang H, Zhou H, Peden DB. Vitamin E, gamma-tocopherol, reduces airway neutrophil recruitment after inhaled endotoxin challenge in rats and in healthy volunteers. Free Radic Biol Med. 2013 Jul;60:56-62. doi: 10.1016/j.freeradbiomed.2013.02.001. Epub 2013 Feb 9.
PubMed 23402870Burbank AJ, Duran CG, Pan Y, Burns P, Jones S, Jiang Q, Yang C, Jenkins S, Wells H, Alexis N, Kesimer M, Bennett WD, Zhou H, Peden DB, Hernandez ML. Gamma tocopherol-enriched supplement reduces sputum eosinophilia and endotoxin-induced sputum neutrophilia in volunteers with asthma. J Allergy Clin Immunol. 2018 Apr;141(4):1231-1238.e1. doi: 10.1016/j.jaci.2017.06.029. Epub 2017 Jul 20.
PubMed 28736267
Study at a glance
From the registry record, last updated by the sponsor on 8 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase I/II Randomized Cross-over Study of Hypertonic Saline on Airway Inflammatory Response to Inhaled Wood Smoke
- ClinicalTrials.gov ID
- NCT03851406
- Acronym / sponsor ID
- Smokeysal / 18-1895
- Conditions
- Airway Inflammation
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 9 participants (actual)
- Lead sponsor
- University of North Carolina, Chapel HillUniversity, hospital or other
- Collaborators
- United States Department of Defense
- Study start
- 1 Aug 2019 (actual)
- Primary completion
- 12 Sep 2024 (actual)
- Study completion
- 12 Sep 2024 (actual)
- First posted
- 22 Feb 2019 (actual)
- Results
- Posted 8 Aug 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Deployment of military personnel has been associated with increased respiratory illness likely due, in part, to inhalation of unusual particulate matter (PM), such as from burn pits. Inflammation is a key initial response to inhaled particulates. The investigator has developed a protocol using inhaled wood smoke particles (WSP) as a way to study PM-induced airway inflammation. Exposure to wood smoke particles causes symptoms, even in healthy people, such as eye irritation, cough, shortness of breath, and increased mucous production. The purpose of this research study is to see if a single treatment of inhaled hypertonic saline (HS) can diminish this PM-induced airway inflammation by rapidly clearing the WSP inhaled particles from airway surfaces. The exposure will be 500 ug/m³ of WSP for 2 hours, with intermittent exercise on a bicycle and rest. The wood is burned in a typical wood stove and piped into the chamber.
Detailed description
Military deployment is associated with exposure to novel particulate matter (PM), such as from burn pits, aeroallergens, and increased cigarette consumption. War fighters exposed to these inhalational exposures exhibit immediate and chronic respiratory morbidity. For example, military service personnel surveyed in both the Republic of Korea (ROK) and Kabul, Afghanistan reported a general increase in respiratory morbidity, including asthma and chronic bronchitis, associated with their deployment. Air contaminants in the ROK were characterized by elevated levels of both PM 0.5-2.5 and PM 2.5-10. Similarly, exposures in Kabul were characterized by multiple airborne PM exposures, including those from burn pits. Burn pit PM includes metals, bioaerosols, organic by-products, and biomass combustion particles. These findings indicate that inhaled PM is a likely cause of respiratory morbidity in the field.
Inflammation is a key initial response to inhaled particulates. Wood smoke particles (WSP) serve as a model agent to study PM-induced bronchitis. WSP inhalation generates reactive oxidant (and nitrosative) species which cause local injury of airway epithelial cells and release of damage-associated molecular patterns (DAMPs) that activate toll-like receptors (TLR) and interleukin 1 (IL-1)-mediated innate immune responses by resident airway macrophages. Contamination of PM with bioaerosols, which contain lipopolysaccharide (LPS), also activates innate immune responses through toll-like receptor 4 (TLR4) activation of resident airway macrophages. These complementary processes result in recruitment of neutrophils (PMN), which mediate luminal airway inflammation with release of toxic mediators such as neutrophil elastase and myeloperoxidase that promote acute and chronic bronchitis.
Therefore, mitigation of PM-induced airway neutrophilic inflammation should be a key focus in order to reduce the respiratory morbidity of military personnel. The investigators have studied a number of pro-inflammatory inhaled agents, such as nebulized LPS, ozone (O3), and WSP, as models of acute neutrophilic bronchitis against which to test a number of therapeutic agents. To this effect, the investigators have reported that inhaled fluticasone inhibits O3-induced and LPS-induced neutrophilic inflammation, and that parenteral anakinra and oral gamma-tocopherol inhibit neutrophilic responses to inhaled LPS. In addition to agents with inherent anti-inflammatory and anti-oxidant properties, rapid clearance of inhaled particles from airway surfaces is a complementary approach to reduce PM-induced airway inflammation. This can be assessed through the measurement of mucociliary clearance (MCC).
MCC is dependent on airway secretory cells and submucosal glands that produce a mucin-rich fluid layer on the airway surface and ciliated cells that hydrate and propel mucus out of the lung and into the upper airway. Rates of MCC are dependent on ciliary beat frequency, hydration, and the rheologic properties of mucus. In vitro studies have demonstrated that HS, through an osmotic effect on airway surfaces, improved hydration and mucus rheologic properties, and accelerated mucus transport rates. In addition, the data over the last 30 years has shown that inhaled hypertonic saline (HS) plus cough is the most effective method for acutely clearing the bronchial airways of inhaled, deposited particles. The combined effect is greater than either HS or cough alone. In the studies of asthmatics, the investigators examined the ability of a single HS treatment with a coached cough maneuver to acutely clear radiolabeled Tc99m sulfur colloid particles from airways following LPS exposure. Following HS inhalation and cough clearance maneuvers developed to recover sputum samples for analysis, the investigators observed a rapid clearance of >50% of the inhaled radiolabelled particles. The investigators hypothesize that if other pro-inflammatory particles (PMs, burn pit particles) were cleared similarly via HS-induced acceleration of MCC shortly after exposure, there would be reductions in acute PM-induced inflammation. Thus, in this study, the investigators will assess the effectiveness of inhaled 5% HS, a dose well tolerated by asthmatics at baseline and after inhaled LPS/allergen challenges for sputum induction, in mitigating WSP-induced airway neutrophilic inflammation in healthy volunteers. Normal saline 0.9% (NS) is not going to be used as a placebo treatment in this study, as inhalation of NS itself impacts the rheologic properties of mucus and MCC and thus would not be a suitable placebo. The investigators will, therefore, compare treatment with 5% HS to no receiving no treatment following WSP exposure.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- To determine the efficacy of nebulized 5% hypertonic saline (HS) (v. no treatment) in mitigating wood smoke particulate (WSP)-induced neutrophilic airway inflammation, assessed via sputum %polymorphonuclear leukocytes (PMNs), in healthy adults 4 hours post WSP exposure.
| Arm | Type | Receives |
|---|---|---|
| 5% Hypertonic Saline, then No Inhaled Treatment | Active comparator | Device: 5% Hypertonic Saline, Other: No treatmentParticipants will receive 5% Hypertonic Saline following WSP exposure. After a 2-week washout period, participants will receive no treatment following WSP exposure. |
| No Inhaled Treatment, then 5% Hypertonic Saline | Active comparator | Device: 5% Hypertonic Saline, Other: No treatmentParticipants will receive no inhaled treatment following WSP exposure. After a 2-week washout period, participants will receive 5% Hypertonic Saline following WSP exposure. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (8 listed)
- Age 18-45 years, inclusive, of both genders
- Negative pregnancy test for females who are not s/p hysterectomy with oophorectomy
- No history of episodic wheezing, chest tightness, or shortness of breath consistent with asthma, or physician-diagnosed asthma.
- forced expiratory volume at one second (FEV1) of at least 80% of predicted and FEV1/forced vital capacity (FVC) ratio of >0.70.
- Oxygen saturation of >93%
Key exclusion criteria (18 listed)
- Clinical contraindications:
- Any chronic medical condition considered by the PI as a contraindication to the exposure study including significant cardiovascular disease, diabetes, chronic renal disease, chronic thyroid disease, history of chronic infections/immunodeficiency.
- Viral upper respiratory tract infection within 4 weeks of challenge.
- Any acute infection requiring antibiotics within 4 weeks of exposure or fever of unknown origin within 4 weeks of challenge.
- Abnormal physical findings at the baseline visit, including but not limited to abnormalities on auscultation, temperature of 37.8° C, Systolic BP > 150mm Hg or < 85 mm Hg; or Diastolic BP > 90 mm Hg or < 50 mm Hg, or pulse oximetry saturation reading less than 93%.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| 5% Hypertonic SalineImmediately following exit from the wood smoke chamber, participants will inhale 15 mL of 5% Hypertonic Saline for 15 minutes delivered by Pari neb with a coached cough maneuver. | Device | 5% Hypertonic Saline, then No Inhaled Treatment, No Inhaled Treatment, then 5% Hypertonic Saline |
| No treatmentNo inhaled treatment will be provided immediately following exit from the wood smoke chamber. | Other | 5% Hypertonic Saline, then No Inhaled Treatment, No Inhaled Treatment, then 5% Hypertonic Saline |
Primary outcome
Change From Baseline to 4 Hours in Sputum Percent Neutrophils
Time frame: Baseline, 4 hours post WSP exposure
Change in sputum percent neutrophils from baseline to 4 hours post WSP exposure
Change From Baseline to 24 Hours in Sputum Percent Neutrophils
Time frame: Baseline, 24 hours post WSP exposure
Change in sputum percent neutrophils from baseline to 24 hours post WSP exposure
7 secondary outcomes
Change in Number of Sputum Neutrophils
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Number of Sputum Eosinophils
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Percent Sputum Eosinophils
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-1b
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-6
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Interleukin-8
Time frame: Baseline, 4 and 24 hours post WSP exposure
Change in Tumor Necrosis Factor Alpha
Time frame: Baseline, 4 and 24 hours post WSP exposure
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Aug 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 27136656Pugh MJ, Jaramillo CA, Leung KW, Faverio P, Fleming N, Mortensen E, Amuan ME, Wang CP, Eapen B, Restrepo M, Morris MJ. Increasing Prevalence of Chronic Lung Disease in Veterans of the Wars in Iraq and Afghanistan. Mil Med. 2016 May;181(5):476-81. doi: 10.7205/MILMED-D-15-00035.
- Background: PubMed 25278277Korzeniewski K, Nitsch-Osuch A, Konior M, Lass A. Respiratory tract infections in the military environment. Respir Physiol Neurobiol. 2015 Apr;209:76-80. doi: 10.1016/j.resp.2014.09.016. Epub 2014 Sep 30.
- Background: PubMed 22815164Baird CP. Review of the Institute of Medicine report: long-term health consequences of exposure to burn pits in Iraq and Afghanistan. US Army Med Dep J. 2012 Jul-Sep:43-7. No abstract available.
- Background: PubMed 25100610Gomez JC, Yamada M, Martin JR, Dang H, Brickey WJ, Bergmeier W, Dinauer MC, Doerschuk CM. Mechanisms of interferon-gamma production by neutrophils and its function during Streptococcus pneumoniae pneumonia. Am J Respir Cell Mol Biol. 2015 Mar;52(3):349-64. doi: 10.1165/rcmb.2013-0316OC.
- Background: PubMed 27930474Barth SK, Dursa EK, Bossarte R, Schneiderman A. Lifetime Prevalence of Respiratory Diseases and Exposures Among Veterans of Operation Enduring Freedom and Operation Iraqi Freedom Veterans: Results From the National Health Study for a New Generation of U.S. Veterans. J Occup Environ Med. 2016 Dec;58(12):1175-1180. doi: 10.1097/JOM.0000000000000885.
- Background: PubMed 24443711Szema AM. Occupational Lung Diseases among Soldiers Deployed to Iraq and Afghanistan. Occup Med Health Aff. 2013;1:10.4172/2329-6879.1000117. doi: 10.4172/2329-6879.1000117.
- Background: PubMed 23470637Morris MJ, Lucero PF, Zanders TB, Zacher LL. Diagnosis and management of chronic lung disease in deployed military personnel. Ther Adv Respir Dis. 2013 Aug;7(4):235-45. doi: 10.1177/1753465813481022. Epub 2013 Mar 7.
- Background: PubMed 22306553Auerbach A, Hernandez ML. The effect of environmental oxidative stress on airway inflammation. Curr Opin Allergy Clin Immunol. 2012 Apr;12(2):133-9. doi: 10.1097/ACI.0b013e32835113d6.
- Background: PubMed 18426139Alexis NE, Brickey WJ, Lay JC, Wang Y, Roubey RA, Ting JP, Peden DB. Development of an inhaled endotoxin challenge protocol for characterizing evoked cell surface phenotype and genomic responses of airway cells in allergic individuals. Ann Allergy Asthma Immunol. 2008 Mar;100(3):206-15. doi: 10.1016/S1081-1206(10)60444-9.
- Background: PubMed 20540623Hernandez ML, Harris B, Lay JC, Bromberg PA, Diaz-Sanchez D, Devlin RB, Kleeberger SR, Alexis NE, Peden DB. Comparative airway inflammatory response of normal volunteers to ozone and lipopolysaccharide challenge. Inhal Toxicol. 2010 Jul;22(8):648-56. doi: 10.3109/08958371003610966.
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- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Terry Noah, M.D principal investigator
UNC Chapel Hill
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing 5% Hypertonic Saline and No treatment in people with Airway Inflammation, run by University of North Carolina, Chapel Hill at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 18 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 8 Aug 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change From Baseline to 4 Hours in Sputum Percent Neutrophils (time frame: Baseline, 4 hours post WSP exposure). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03851406, which also lists 23 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Aug 2025; AzTrials last refreshed its copy on 29 Oct 2026.