Window Prophylaxis for Pediatric Tuberculosis Prevention Trial
Chile647 participantsStarted 2025-10-27
Plain-language summary
The goal of this cluster-randomized controlled trial is to evaluate the effectiveness of tuberculosis preventive treatment (TPT) administered during the "window period" to prevent new Mycobacterium tuberculosis infections in children and adolescents.
The main question it aims to answer is:
Can immediate TPT reduce the incidence of IGRA conversions in children and adolescents who are household contacts of a newly diagnosed pulmonary tuberculosis patient?
Researchers will compare the incidence of new tuberculosis infections-measured by IGRA conversion at 12 weeks-between participants who receive immediate TPT while still uninfected (baseline IGRA-negative) and those who receive standard care, in which TPT is not offered to IGRA-negative contacts.
Participants will be:
1. Tested for M. tuberculosis infection using the Interferon-Gamma Release Assay (IGRA), specifically the QuantiFERON-TB Gold Plus, at enrollment and after 12 weeks of follow-up.
2. Take weekly isoniazid and rifapentine for 12 weeks if:
1. They are assigned to the intervention arm (regardless of baseline IGRA result), or
2. They are in the control arm and test IGRA-positive at baseline.
Additionally, participants from the control arm who experience an IGRA conversion at 12 weeks (following the primary outcome assessment) will also receive TPT, as per standard of care.
Who can participate
Age range
5 Years – 17 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Household contacts of patient (index case) with a new diagnosis of microbiologically confirmed pulmonary tuberculosis
* Age ≥5 to \<18 years old
Exclusion Criteria:
* Suspected active tuberculosis in initial assessment (clinical or radiological)
* Current pregnancy or breastfeeding
* Immunocompromised
* Allergy or contraindication to isoniazid or rifapentine
* Chronic liver disease or alcohol use disorder
* History of previous treatment for active or latent tuberculosis infection
* Previous tuberculin skin test
* Household contacts of a tuberculosis index patient with a known or suspected drug-resistant M. tuberculosis strain
* Household contacts or a tuberculosis index patient currently living away from home for more than four weeks
* Household contacts of a tuberculosis index patient who have already received more than 15 daily doses of antituberculous treatment
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Incidence of new tuberculosis infections (all IGRA conversions) from enrollment until the end of follow-up in both study arms
Timeframe: At the end of follow-up at 12 weeks (accepted range: ≥ 12 - ≤16 weeks)