NCT04722835 · University of California, San Francisco
Lung Macrophage Populations and Functions in Chronic Obstructive Pulmonary Disease (COPD)-Susceptible Smokers
(Pre-COPD Pilot)
What this study is about
Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous disease that affects only a fraction of those who smoke tobacco. The origin of this variability in susceptibility to develop COPD is unclear, but understanding its underlying biology has important implications for our ability to design suitable preventative and therapeutic strategies for its management.
View original scientific description
Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous disease that affects only a fraction of those who smoke tobacco. The origin of this variability in susceptibility to develop COPD is unclear, but understanding its underlying biology has important implications for our ability to design suitable preventative and therapeutic strategies for its management. This Department of Defense (DOD) discovery research proposes to develop methodologies and generate preliminary data needed to lay the foundation for a large study that would investigate the underlying biological susceptibility of those who smoke tobacco to develop COPD.
Interventions
PROCEDURE
Bronchoscopy with Bronchoalveolar Lavage (BAL)
1. Bronchoscopy w/ (BAL): The bronchoscope will be introduced through mouth and directed into the right middle lobe bronchus for bronchial lavage. The BAL will be performed with two 60-mL aliquots (total of 120 ml) of saline in each of medial and lateral segments of Right Middle Lobe (RML) (total 240 ml lavage). 2. Albuterol Administration: The subjects will inhale 2 puffs of respiratory medication albuterol, then repeat the breathing test. 3. Peak Flow Measurement: Subjects will breathe in fully then out forcefully into the handheld device. 4. Pulmonary Function Test w/ Spirometry: will be used for determination of COPD and its severity. The PFT measures breathing capacity and lung function with different types of breathing maneuvers including flow-volume curve, single breath CO diffusing capacity, and total lung capacity. 5. Blood draw 6. Medical Health and Symptom Questionnaires 7. Physical Exam by study doctor to determine suitability and safety for participation.
Primary outcome measures
Prevalence of macrophage sub-populations in airway lumen.
Time frame: 4 weeks
Number of macrophages measured by flow cytometry.
Functional status of macrophage sub-populations in airway lumen.
Time frame: 4 weeks
Relative percentage of macrophages measured by flow cytometry.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Ages between 40 to 75 years old.
- History of at least 20 pack-years of smoking.
- No diagnosis of COPD or asthma.
- No spirometric evidence of airflow obstruction as determined by FEV1/FVC ratio ≥0.7.
- FEV1 and FVC \>lower limit of normal.
- Less than 1 pack-year history of tobacco smoking and no tobacco use within the past 12 months.
- Subjects will be divided into two groups by their RV/TLC: Normal RV/TLC Group: • Plethysmographic RV/TLC equal or less than lower limit of normal. Abnormal RV/TLC Group: • Plethysmographic RV/TLC higher than lower limit of normal.
Exclusion criteria
- Any history of IV drug use or inhalation of recreational drugs other than marijuana: A- within the past 20 years. B- more than 100 times IV drug usage. C- longer than 1 year usage.
- Marijuana use \>400 joints in lifetime or any within past 6 months.
- Inability to walk briskly, run on treadmill, or pedal on ergometer to perform the study-required exercise level.
- Pregnant/breast feeding.
- Serious and active heart conditions- defined by stable or unstable angina, recent myocardial infarction (within the last 2 years), active congestive heart failure, ischemic cardiomyopathy.
- Liver cirrhosis.
- History of chronic active Hepatitis B or C.
Where
- San Francisco, California
Collaborators
United States Department of Defense
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 4, 2026 · Source of record for eligibility and locations