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Range of Neutrophil Response to 20,000 EU of Clinical Center Reference Endotoxin in Otherwise Healthy Smokers

Range of Neutrophil Response to 20,000 EU of Clinical Center Reference Endotoxin in Otherwise Healthy Smokers

Status
Terminated
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00753870
Enrollment
2
Registered
2008-09-17
Start date
2008-08-31
Completion date
2009-12-31
Last updated
2011-04-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy Smokers

Keywords

current, no health problems, no daily cough from smoking

Brief summary

Endotoxin is a component of outdoor air pollution, an air contaminant found in a number of different workplaces, and is even found in homes. The endotoxin used for this study is obtained from the National Institutes of Health, and is called Clinical Center Reference Endotoxin, or CCRE. The purpose of this Phase 1 research study is to identify a dose of inhaled endotoxin that is safe (does not cause prolonged cough, shortness of breath or other problems), but causes changes in sputum cell samples that the scientists can measure. Phase 1 research studies like this one are not intended to be a treatment, but are a scientific investigation. Eventually, with these types of studies we will be able to examine why some people are more sensitive to endotoxin. Scientists at other universities have found that while most people do not have a considerable lung response to endotoxin at doses as high as 60,000 EU (endotoxin units), a few respond to as little as a total dose of 4500 EU. Our study is designed to identify if using a dose of 20,000 EU causes changes in the lung cells but does not cause symptoms in our study subjects. In our previous studies in our lab, using an endotoxin from another source, we have used higher doses (15,000 EUs) in subjects with asthma with no major problems, and we have used 10,000 EUs of CCRE in subjects who are current smokers without seeing any problems.

Detailed description

We are looking for people who currently smoke a minimum of a half a pack of cigarettes each day. You must not have any other health problems, be pregnant or nursing a baby, or actively trying to become pregnant or to father a child.

Interventions

BIOLOGICALCCRE inhalation

20,000 EU CCRE given as a one-time challenge

Sponsors

National Institutes of Health (NIH)
CollaboratorNIH
National Heart, Lung, and Blood Institute (NHLBI)
CollaboratorNIH
University of North Carolina, Chapel Hill
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* current smoker * healthy

Exclusion criteria

* no asthma * no chronic health conditions * no daily cough * not pregnant or nursing a baby * not actively trying to get pregnant or father a child

Design outcomes

Primary

MeasureTime frame
To identify a dose of inhaled CCRE that is well tolerated and that induces measurable increases in neutrophil content of induced sputum that can be employed to screen large populations for susceptibility to the inflammatory effect of inhaled endotoxin.post exposure

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026