Functional CT Assessment for Emphysema

Recruiting in Palo Alto (17 mi)

Overseen by Eric A Hoffman, PhD

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 4

Recruiting

Sponsor: Eric A. Hoffman

No Placebo Group

Prior Safety Data

Trial Summary

What is the purpose of this trial?

This study will use dual energy x-ray computed tomography (DECT) to evaluate the relationship between heterogeneous perfusion, hypoxia (low oxygen in inspired gas) and induction of pulmonary vascular dilatation to characterize emphysema susceptibility in a normal smoking population. The investigators will correlate DECT measures of perfusion with lung injury measured by single photon emission computed tomography (SPECT). The investigators will study the effect of pulmonary arterial vasodilation to see if it eliminates indices of persistent lung injury in smokers that are susceptible to emphysema

Research Team

Eric A Hoffman, PhD

Principal Investigator

University of Iowa

Eligibility Criteria

This trial is for current smokers aged 25-65 with specific lung function test results, indicating either normal or mildly impaired lungs. It's not for pregnant/breastfeeding women, those overweight (BMI>32), with heart/kidney/diabetes issues, asthma, severe kidney dysfunction, allergies to certain substances like shellfish or iodine, and those on heart/lung-affecting meds.

Inclusion Criteria

Must be able to give informed consent for self

You must be between 25 and 65 years old.

You must currently be smoking at least half a pack of cigarettes per day, as confirmed by a test for cotinine.

Exclusion Criteria

Pregnant or breastfeeding females

Your kidneys are not filtering blood well, with a rate of 60 cc per minute or less.

If you are taking nitroglycerin or other nitrates, or if you have used certain medications for erectile dysfunction within the last 7 days, you cannot participate. Also, if you are allergic to Sildenafil, you cannot participate.

Treatment Details

Interventions

• Hyperoxia administration study group (Drug)
• Hypoxia administration study group (Drug)
• Sildenafil (Phosphodiesterase-5 (PDE-5) Inhibitor)

Trial Overview The study tests how low oxygen (hypoxia) and high oxygen (hyperoxia) conditions affect blood flow in the lungs using special CT scans. It also looks at whether a drug called Sildenafil can improve signs of lung damage in smokers prone to emphysema by dilating pulmonary arteries.

Participant Groups

Group I: Sildenafil Experimental Treatment 1 Intervention

40 subjects (20M and 20F) will be recruited to study non-contrast imaging at TLC and 20%VC and with contrast using DECT scans to assess perfused blood volume. For the intervention, the subject will be administered 20 mg of sildenafil and then the same scanning will be repeated one hour after sildenafil administration.

Group II: Hypoxia Administration study group Experimental Treatment 1 Intervention

40 subjects will be recruited to study normoxia oxygen compared to hypoxia oxygen. 20M and 20F subjects will be evaluated under normoxia oxygen with low dose non-contrast CT scans at total lung capacity (TLC) and 20% vital capacity (VC) and then with contrast using dual energy CT scans to evaluate heterogeneity of perfused blood volume (PBV). For the intervention, following the normixia scans, hypoxia administration will be administered by breathing an inspired FIO2 of 15% oxygen and the non-contrast and contrast using DECT scans to evaluate heterogeneity of perfused blood volumen will be completed.

Group III: Hyperoxia Administration study group Experimental Treatment 1 Intervention

40 subjects will recruited to study normoxia oxygen scans compared to hyperoxia scans. 20M and 20F subjects will be evaluated under normoxia with low dose non-contrast CT scans at TLC and 20% vital capacity (VC) and then with contrast scans using DECT to evaluate heterogeneity of perfused blood volume (PBV). For the intervention, following the normoxia scans, hyperoxia administration will be administered by breathing an inspired FIO2 of 100% oxygen and the non-contrast and contrast using DECT to evaluate heterogeneity of perfused blood volumen will be completed.

Who Is Running the Clinical Trial?

Eric A. Hoffman

Lead Sponsor

Trials

5

Recruited

620+

National Institutes of Health (NIH)

Collaborator

Trials

2,896

Recruited

8,053,000+

Dr. Jeanne Marrazzo

National Institutes of Health (NIH)

Chief Medical Officer

MD from University of California, Los Angeles

Dr. Jay Bhattacharya

National Institutes of Health (NIH)

Chief Executive Officer

MD, PhD from Stanford University

National Heart, Lung, and Blood Institute (NHLBI)

Collaborator

Trials

3,987

Recruited

47,860,000+

Dr. Gary H. Gibbons

National Heart, Lung, and Blood Institute (NHLBI)

Chief Executive Officer since 2012

MD from Harvard Medical School

Dr. James P. Kiley

National Heart, Lung, and Blood Institute (NHLBI)

Chief Medical Officer since 2011

MD from University of California, San Francisco