For Healthcare Professionals

Bacille Calmette Guerin (BCG) Revaccination of Healthy Adolescents for the Prevention of Mycobacterium Tuberculosis Sustained Infection


About the study

The purpose of this study is to demonstrate the efficacy of Bacille Calmette Guerin (BCG) revaccination against sustained Mycobacterium tuberculosis infection versus placebo in previously BCG vaccinated QuantiFERON®-TB Gold Plus Assay (QFT) negative, healthy adolescents.

Who can take part

You may be eligible to participate in the study if you meet the following criteria:


Inclusion Criteria:

  1. Participant between ≥ 10 years and ≤ 18 years on Study Day 1
  2. General good health, confirmed by medical history and physical examination
  3. Vaccinated with Bacille Calmette Guerin (BCG) at least 5 years ago, documented through medical history or by presence of healed BCG scar
  4. Tests QuantiFERON®-TB Gold Plus Assay (QFT) negative at screening.
  5. For female participants: not pregnant and agrees to avoid pregnancy throughout the first 12 months of the study. Women physically capable of pregnancy must agree to use an acceptable method of avoiding pregnancy during this period. Acceptable methods of avoiding pregnancy include sexual abstinence (not engaging in sexual intercourse), a confirmed sterile partner, or at least 2 contraception methods from the following list: male or female condom, diaphragm, intrauterine devices (IUDs), hormonal contraceptive (oral, injection, transdermal patch, or implant).
  6. Agrees to stay in contact with the study site for the duration of the study, provide updated contact information as necessary, and has no current plans to move from the study area for the duration of the study
  7. Capable of giving signed informed consent/assent and completes the written informed consent/assent process.


Exclusion Criteria:

  1. Acute illness on Study Day 1. NOTE: This is a temporary exclusion for which the participant may be re-evaluated
  2. Body temperature ≥37.5 degree Celsius on Study Day 1. NOTE: This is a temporary exclusion for which the participant may be re-evaluated
  3. History or evidence of any clinically significant disease, including severe eczema and severe asthma, or any acute or chronic illness that might affect the safety, immunogenicity, or efficacy of study vaccine in the opinion of the investigator
  4. Any current medical, psychiatric, occupational, or substance abuse problems that, in the opinion of the investigator, will make it unlikely that the participant will comply with the protocol
  5. History of autoimmune disease
  6. History or evidence of active tuberculosis (TB) disease
  7. History or laboratory evidence of any past or present possible immunodeficiency state including, but not limited to, any laboratory indication of human immunodeficiency virus - 1 (HIV-1) infection
  8. History of allergic disease that is likely to be exacerbated by any component of the study vaccine
  9. History of treatment for active TB disease or history of latent Mycobacterium tuberculosis infection
  10. Received a tuberculin skin test within 6 months prior to Study Day 1
  11. Received immunosuppressive treatment, e.g., chemotherapy, biologics or radiation therapy, or used immunosuppressive medication (daily steroid equivalent of ≥5 milligrams prednisone) within 42 days before Study Day 1. Inhaled and topical corticosteroids are permitted.
  12. Received immunoglobulin or blood products within 42 days before Study Day 1
  13. Planned administration/administration of a licensed vaccine in the period starting 28 days before and ending 28 days after Study Day 1
  14. Received investigational TB vaccine at any time prior to Study Day 1
  15. Received any investigational drug therapy or investigational vaccine within 180 days before Study Day 1, or planned participation in any other clinical trial using investigational product during the study period
  16. Laboratory values from the most recent blood collected prior to randomization outside the normal range that are suggestive of a disease state. Grade 1 abnormalities (as per Division of Acquired Immunodeficiency Syndrome toxicity table version 2.1) do not lead to exclusion if the investigator considers them not clinically significant
  17. Urinalysis abnormality greater than Grade 1 on the Toxicity Scale (with the exception of hematuria in a menstruating female), or urinalysis abnormality judged clinically significant by the investigator
  18. Shared residence with an individual who is receiving TB treatment or with someone who is known to have incompletely treated TB. e.g., Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) assay-positive, polymerase chain reaction-positive, culture-positive, smear-positive TB, or clinically diagnosed unconfirmed TB
  19. Child in Care
  20. Female participants currently pregnant or lactating/nursing; or positive serum pregnancy test during screening or on Day 1, prior to vaccination, or planning a pregnancy within the first 12 months after study intervention

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Study Locations

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How to Apply

Contact the study center to learn if this study is a good match for you.

Study’s details



Age (in years)

10 - 18


Phase 2

Participants needed


Est. Completion Date

Sep 1, 2025

Treatment type



Bill & Melinda Gates Medical Research Institute identifier


Study number

Gates MRI TBV01201

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