An observational study in Asthma, sponsored by National Institute of Environmental Health Sciences (NIEHS). Recruiting at 1 site in United States. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by National Institute of Environmental Health Sciences (NIEHS) · Observational
Background:
- Asthma is a serious clinical and public health problem. Researchers want to collect data to better understand how bacteria and other things in the environment can affect people's asthma.
Eligibility:
- Nonsmoking adults age 18 - 60 who have moderate to severe asthma.
Design:
This study will be a prospective, longitudinal, observational, single-center, exploratory, natural history study to collect samples and data that will enable prospective explorations of the interaction between environmental exposures and disease progression over time in moderate-severe atopic asthmatics with persistent disease, and facilitate the formation of mechanistic hypotheses. Environmental and body microbiome samples will be collected and stored from participants for future correlation to effects on asthma symptoms and control.
Samples of blood, urine, DNA, saliva, sputum, stool, and household dust will be collected from approximately 200 participants, as well as quality of life information using asthma symptom questionnaires and, if consented, through the use of home devices. Additionally, samples will be collected from the airways of participants enrolled in the bronchoscopy visit. The samples and survey information collected may be used to explore the microbiological and genetic influences of atopic asthma. Data from the analyses of these samples and survey responses may be evaluated in the context of the environmental exposures, clinical outcomes (symptoms, exacerbations, and quality of life), and response to therapy.
Male and female participants aged 18 to 60 years old with moderate-severe, symptomatic atopic asthma will be enrolled. Participants will be excluded from enrollment if they have a history of chronic obstructive pulmonary disease, cystic fibrosis, non-cystic fibrosis bronchiectasis, pulmonary fibrosis, pulmonary hypertension, emphysema, sarcoidosis, or unstable angina. Additionally, participants will be excluded if they have DVT, pulmonary embolism, class III - IV congestive heart failure, or a malignancy under treatment. Current smokers, and individuals who are allergic to methacholine will not be eligible to enroll. Participants will be enrolled for five years and will receive standard of care asthma therapy as indicated. After the initial screening and baseline visits, participants will return for visits semi-annually and for sick visits as needed. Volunteers participating in the bronchoscopy visit will have an additional single visit after completing the baseline visit.
This cohort of 200 participants will form the basis for future asthma study recruitment, and analysis of collected samples and data. Further expansion of the study beyond five years and 200 participants will be desirable if logistically possible.
4,841 studies on the registry are indexed under Asthma; 600 are open to participants now.
This study's planned enrollment of 400 is above the median of 158 across 1,250 observational studies indexed under Asthma.
Browse Asthma studies →National Institute of Environmental Health Sciences (NIEHS) is the lead sponsor of 183 studies on the registry; 18 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Participants will be recruited from the population at large, including asthmatic participants who visit the CRU for on-going studies. Participants who have successfully completed other CRU studies may be recruited directly for this study. The study will be registered on clinicaltrials.gov. Local public health departments and other clinics may be contacted for help with recruitment of individuals with moderate to severe atopic asthma. In addition, if needed, the study may be advertised in local media outlets.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Participants must meet all of the following criteria for enrollment:
Must have clinical evidence of moderate-severe atopic asthma:
within the past year, and
--*a positive methacholine test confirming diagnosis [provocative concentration causing a 20% fall in (PC20 FEV1) \<16 mg/mL for participants on inhaled and \<8 mg/mL for participants not on inhaled corticosteroids] or postbronchodilator FEV1 with at least 12% or 200 mL increase in FEV1 or forced volume vital capacity (FVC) on bronchodilator challenge, and
--no other diagnosis that could explain symptoms.
If there is documentation of a recent methacholine challenge, those results may be used in lieu of conducting a secondary methacholine challenge.
Access to a vacuum cleaner with a detachable hose component
Bronchoscopy Visit Inclusion Criterion
In addition to the above inclusion criteria, participants must be able to fast for 6 hours (no food or drink, except a small amount of water if needed to take approved medications) prior to the bronchoscopy visit in order to be eligible for enrollment in the bronchoscopy visit.
Exclusion Criteria
Participants meeting any of the following criteria at screening will not be eligible for enrollment or to continue with study visits:
Bronchoscopy Visit Exclusion Criteria
In addition to the above exclusion criteria, participants meeting any of the following criteria will not be eligible for enrollment into the bronchoscopy visit:
The following abnormal lab values (values obtained during clinical assessment):
If a participant is recruited for the Bronchoscopy Visit but does not have current lab values (within 4 weeks), the participant may be asked to return to the CRU for an additional blood draw in order to run the requisite clinical assessments for safety purposes. The participant will be compensated for the additional visit. This is anticipated to be a rare occurrence, as the study team will make all efforts to schedule and complete the bronchoscopy procedure while the lab results are current.
Participants with active bronchospasm on the day of the bronchoscopy will not undergo bronchoscopy.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
study group
controls
The overall goal is to study the natural history of atopic asthma, focusing on moderate to severe asthma. The primary objective is to collect prospective data and samples for future use to better understand the interaction between environmental ...
Results will be evaluated in the context of the environmental exposures, clinical outcomes (symptoms, exacerbations, and quality of life), and response to therapy.
Time frame: End of Study
Plan to share: Undecided — It isn t known yet if there will be a plan to make IPD available
Started Sep 2015 (actual). Primary completion is estimated for Apr 2030, 174 months after the start.
Of 364 non-industry observational studies under Asthma, half reached primary completion within 38 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 97. This study's planned 174 months is above that.
Counting every sponsor, half of 454 studies reached it within 36 months; a quarter within 18 and three quarters within 82.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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