PPD Challenge for Tuberculosis
What You Need to Know Before You Apply
What is the purpose of this trial?
This trial aims to understand how lung cells respond when exposed to Tuberculin Purified Protein Derivative (PPD), a test for tuberculosis (TB). Typically, PPD is used in skin tests to check for TB exposure, but in this trial, it will be applied directly in the lung. The trial seeks adults who have been exposed to TB but show no symptoms or those who have never been exposed. Participants will undergo several procedures, including scans and a bronchoscopy, where a tube is inserted into the lungs to collect cells. This research could enhance understanding of the immune response in the lungs. As an Early Phase 1 trial, it focuses on understanding how the treatment works in people, offering participants a chance to contribute to groundbreaking scientific knowledge.
Do I need to stop taking my current medications to join the trial?
Yes, you will need to stop taking certain medications. Specifically, you must suspend the use of anticoagulant therapy (blood thinners) within 7 to 14 days before the bronchoscopy procedure.
What prior data suggests that this method is safe for lung application?
Research has shown that Tuberculin Purified Protein Derivative (PPD) is generally safe when used correctly. This substance is the same one used in skin tests to check for tuberculosis (TB). In these tests, some people might experience minor skin reactions, such as redness or a rash at the injection site. These reactions do not indicate a TB infection.
The safety of PPD is well-documented in its use for skin tests. In this study, PPD is being used in the lungs, which is not the usual method. However, because PPD is well-tolerated in its regular use, it is expected to be safe. The trial is in an early phase, so researchers are focusing on ensuring safety and observing how the body responds to the treatment. Since it's early, detailed safety data for this method isn't available yet, but the trial is designed to collect this information.12345Why are researchers excited about this trial?
Researchers are excited about the PPD Challenge for Tuberculosis trial because it explores a new way to evaluate immune response to TB infection using Tuberculin Purified Protein Derivative (PPD). Unlike standard tuberculosis tests, which include methods like the Mantoux test and IGRA blood tests, this approach focuses on assessing immune reactions to specific TB proteins. This trial aims to better understand how different immune responses correlate with TB infection, potentially leading to more accurate diagnostics and a deeper understanding of the disease's progression.
What evidence suggests that this method is effective for studying immune response to TB?
Research has shown that Tuberculin Purified Protein Derivative (PPD) is often used in skin tests to check for tuberculosis (TB) exposure. In these tests, healthcare providers inject PPD just under the skin to observe any reaction, which helps identify TB exposure. A study with over 6,000 people found that about 22% had a positive reaction, suggesting TB exposure. Another study found that strong reactions to PPD can be linked to a better ability to fight TB bacteria. This suggests that PPD can help the immune system recognize and potentially fight TB bacteria. In this trial, participants will be divided into two groups: one with positive skin test and IGRA results (TST+ IGRA+) and another with negative results (TST- IGRA-), to test how PPD affects immune cell responses in the lungs.678910
Who Is on the Research Team?
Kevin P Fennelly, M.D.
Principal Investigator
National Heart, Lung, and Blood Institute (NHLBI)
Are You a Good Fit for This Trial?
Adults aged 18-64, either exposed to TB without active disease or never exposed. Must be healthy with no significant medical issues like heart, lung, kidney diseases, etc., and agree to use effective contraception if of reproductive potential. Can't join if they need oxygen at rest, have HIV, poor tolerance for bronchoscopy, immunosuppressive conditions or medications usage in the last 6 months including steroids.Inclusion Criteria
Exclusion Criteria
Timeline for a Trial Participant
Screening
Participants are screened for eligibility to participate in the trial
Bronchoscopy and PET-CT Procedures
Participants undergo 3 bronchoscopies and 3 FDG PET-CT scans to evaluate immune response to PPD instillation
Follow-up
Participants are monitored for safety and effectiveness after procedures
What Are the Treatments Tested in This Trial?
Interventions
- Tuberculin Purified Protein Derivative (PPD)
Find a Clinic Near You
Who Is Running the Clinical Trial?
National Heart, Lung, and Blood Institute (NHLBI)
Lead Sponsor