Window-period preventive treatment to prevent TB infection in children and adolescents.
Window Prophylaxis for Mycobacterium Tuberculosis Infection Prevention in Child and Adolescent Household Contacts: a Cluster-Randomized Controlled Trial
This trial will try weekly isoniazid plus rifapentine for 12 weeks to see if it prevents TB infection in household contacts aged 5 to 17 years who are IGRA-negative after recent exposure.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 647 (estimated) |
| Ages | 5 Years to 17 Years |
| Sex | All |
| Sponsor | Pontificia Universidad Catolica de Chile Academic / other |
| Locations | 13 sites (Calama, Antofagasta and 12 other locations) |
| Trial ID | NCT07086820 on ClinicalTrials.gov |
What this trial studies
This cluster-randomized controlled trial enrolls household contacts aged 5 to <18 years of microbiologically confirmed pulmonary TB cases and uses baseline and 12-week QuantiFERON-TB Gold Plus IGRA testing to detect new infection. Participants in the intervention arm receive weekly isoniazid and rifapentine for 12 weeks starting during the post-exposure 'window period', while the control arm follows standard care where TPT is not offered to IGRA-negative contacts. The primary outcome is IGRA conversion at 12 weeks, comparing incidence between immediate TPT and standard care clusters. The trial is conducted at regional hospitals in Chile with clinical screening to exclude active TB, pregnancy, immunosuppression, drug-resistant exposure, or contraindications to study drugs.
Who should consider this trial
Good fit: Ideal participants are household contacts aged 5 to <18 years of a newly diagnosed, microbiologically confirmed pulmonary TB case who are IGRA-negative at enrollment and have no contraindications to isoniazid or rifapentine.
Not a fit: Patients who are IGRA-positive at baseline, have suspected active or drug-resistant TB, are immunocompromised, pregnant or breastfeeding, or have prior TB treatment are unlikely to benefit from this prophylaxis approach.
Why it matters
Potential benefit: If successful, window-period TPT could reduce new TB infections in exposed children and adolescents, lowering their future risk of disease and onward transmission.
How similar studies have performed: Smaller trials and observational studies have suggested window-period prophylaxis can reduce TB acquisition in young children, but randomized cluster-level evidence remains limited.
Eligibility criteria
Show full inclusion / exclusion criteria
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
Where this trial is running
Calama, Antofagasta and 12 other locations
- Hospital Dr. Carlos Cisterna — Calama, Antofagasta, Chile (Recruiting)
- Hospital de Coquimbo — Coquimbo, Coquimbo Region, Chile (Not_yet_recruiting)
- Hospital San Juan de Dios de La Serena — La Serena, Coquimbo Region, Chile (Not_yet_recruiting)
- Hospital de Niños Roberto del Río — Independencia, Santiago Metropolitan, Chile (Not_yet_recruiting)
- Hospital Luis Calvo Mackenna — Providencia, Santiago Metropolitan, Chile (Not_yet_recruiting)
- Complejo Asistencial Dr. Sótero Del Río — Puente Alto, Santiago Metropolitan, Chile (Recruiting)
- Hospital CRS El Pino — San Bernardo, Santiago Metropolitan, Chile (Recruiting)
- Hospital Clínico Félix Bulnes — Santiago, Santiago Metropolitan, Chile (Recruiting)
- Hospital Clínico San Borja Arriarán — Santiago, Santiago Metropolitan, Chile (Recruiting)
- Hospital San Juan de Dios de Santiago — Santiago, Santiago Metropolitan, Chile (Not_yet_recruiting)
- Hospital Alto Hospicio — Alto Hospicio, Tarapacá, Chile (Not_yet_recruiting)
- Hospital Claudio Vicuña — San Antonio, Valparaiso, Chile (Not_yet_recruiting)
- Hospital Dr. Gustavo Fricke — Viña del Mar, Valparaiso, Chile (Not_yet_recruiting)
Study contacts
- Study coordinator: María Elvira Balcells, MD
- Email: ebalcells@uc.cl
- Phone: +56 955043508
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.