A Phase 1 interventional study of BCG Vaccine USP and Isoniazid in Tuberculosis, sponsored by Fred Hutchinson Cancer Center. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-12-16.
Sponsored by Fred Hutchinson Cancer Center · Phase 1, Interventional, and Prevention
The purpose of the study is to develop a BCG challenge model for use in short term Phase I human trials capable of assessing the ability of TB drugs and/or vaccine-induced immune responses to impact in vivo mycobacterial replication as a method of assessing antimycobacterial agents and/or protective immunity elicited by vaccines or host-directed therapy. The trial will illuminate the nature of local and systemic immune responses to BCG and treatment response, as well as demonstrate our local capacity for newer, more innovative study designs.
This is phase 1, open-label, randomized clinical protocol to develop a human challenge model using the licensed and available BCG VACCINE USP (TICE® strain) with and without INH or Rifampin (RIF). Part 1 will involve 10 participants who will be screened and consented, given an intradermal injection of BCG; five of these participants will receive oral INH for 3 days. Part 2 will involve 10 participants who will be screened and consented, given an intradermal injection of BCG; five of these participants will receive oral RIF for 7 days. All participants will undergo physical exams, clinical evaluations, blood draws, urine collections, skin biopsies, and pregnancy tests. This study will measure the rate of replication by utilizing qPCR and in vitro culture, systemic innate and adaptive immune responses, including humoral and cellular assay analyses and the evaluation and PPD/IGRA status.
1,417 studies on the registry are indexed under Tuberculosis; 208 are open to participants now.
This study's enrollment of 20 is below the median of 150 across 952 interventional studies indexed under Tuberculosis.
Browse Tuberculosis studies →Fred Hutchinson Cancer Center is the lead sponsor of 537 studies on the registry; 79 are open to participants now.
Of its 57 completed or terminated interventional studies of FDA-regulated products, 45 (79%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Will receive INH in the dose of 300 mg for three days post BCG injection.
Drug: BCG Vaccine USP · Drug: Isoniazid
Will not receive any INH or RIF dose.
Drug: BCG Vaccine USP
Will receive RIF in the dose of 600 mg for seven days post BCG injection.
Drug: BCG Vaccine USP · Drug: Rifampin
2x10\^6 cfu Tice® BCG (ID)
Also known as: BCG
INH in the dose of 300 mg for three days post BCG injection.
Also known as: INH
RIF in the dose of 600 mg for seven days post BCG injection.
Also known as: RIF
Assess Viable BCG Bacteria From Intradermal Challenge Site From Culture.
Through microbial culture, quantify in colony forming units (CFU) BCG bacterial burden in skin biopsies from challenge sites. Outcome measure if the mean cfu from day 15 biopsy specimens.
Time frame: 15 days after BCG dosing
The Rate of AE's/SAE's
Mild (grade 1): events do not require treatment and do not interfere with the patient's daily activities Moderate (grade 2): events result in a low level of inconvenience or concern with the therapeutic measures. Moderate events may cause some interference with functioning and daily activities Severe (grade 3): events interrupt a patient's usual daily activity and may require systemic drug therapy or other treatment. Severe events are usually incapacitating.
Time frame: Through study completion, an average of 16 weeks.
Assess Quantitative Bacterial 16S Ribosomal DNA PCR
Assessing the number of real time BCG genomes present in skin biopsies from challenge sites.
Time frame: Day 15 post BCG dosing
Quantification by AUC of IgG in the Blood After BCG Immunization and INH or RIF Dosing.
To assess the IgG immune response after INH or RIF dosing. The AUC we report is not a integration of concentration over time. Instead, AUC reported here quantifies the overall antibody binding signal across a titration series from a single time point (Day 144). In this assay, each sample from a single visit is measured at multiple dilutions, and the signal is expressed AUC in unit MFI × log₁₀(dilution). Plotting MFI as a function of dilution generates a curve that reflects how strongly and consistently the antibodies bind over the dilution range. The AUC therefore summarizes the entire binding titration curve - capturing both signal intensity and how long the signal is maintained across dilutions.
Time frame: Day 144
Cohort A recruitment period 01 NOV 2022-01 DEC 2022 Cohort B recruitment period 01 JUL 2023-01 AUG 2023
| Milestone | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Started | 5 | 5 | 5 | 5 |
| Completed | 5 | 5 | 5 | 5 |
| Not completed | 0 | 0 | 0 | 0 |
Through microbial culture, quantify in colony forming units (CFU) BCG bacterial burden in skin biopsies from challenge sites. Outcome measure if the mean cfu from day 15 biopsy specimens.
| CFU | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Assess Viable BCG Bacteria From Intradermal Challenge Site From Culture. | 20,440 ± 40,516 | 80 ± 92 | 5 ± 12 | 10,673 ± 12,646 |
Mild (grade 1): events do not require treatment and do not interfere with the patient's daily activities Moderate (grade 2): events result in a low level of inconvenience or concern with the therapeutic measures. Moderate events may cause some interference with functioning and daily activities Severe (grade 3): events interrupt a patient's usual daily activity and may require systemic drug therapy or other treatment. Severe events are usually incapacitating.
| Participants | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| All AEs — Number experiencing any Adverse Event | 5 | 4 | 4 | 5 |
| All AEs — Number experiencing no Adverse Events | 0 | 1 | 1 | 0 |
| Grade 3 AEs — Number experiencing any Adverse Event | 0 | 1 | 0 | 0 |
| Grade 3 AEs — Number experiencing no Adverse Events | 5 | 4 | 5 | 5 |
Assessing the number of real time BCG genomes present in skin biopsies from challenge sites.
| copies | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Assess Quantitative Bacterial 16S Ribosomal DNA PCR | 8239.4 ± 15243.9 | 97.7 ± 115.9 | 5.34 ± 11.9 | 10,673.4 ± 12645.7 |
To assess the IgG immune response after INH or RIF dosing. The AUC we report is not a integration of concentration over time. Instead, AUC reported here quantifies the overall antibody binding signal across a titration series from a single time point (Day 144). In this assay, each sample from a single visit is measured at multiple dilutions, and the signal is expressed AUC in unit MFI × log₁₀(dilution). Plotting MFI as a function of dilution generates a curve that reflects how strongly and consistently the antibodies bind over the dilution range. The AUC therefore summarizes the entire binding titration curve - capturing both signal intensity and how long the signal is maintained across dilutions.
| MFI × log₁₀ dilution | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Quantification by AUC of IgG in the Blood After BCG Immunization and INH or RIF Dosing. | 319.4 (276.3 to 469.1) | 822.5 (192.0 to 946.3) | 2888.8 (1941.878 to 4600.566) | 1951.5 (888.232 to 3436.136) |
Collected over Adverse Events were collected through day 114 after vaccination. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| BCG Challenged-Isoniazid Treated | 0/5 (0%) | 0/5 (0%) | 5/5 (100%) |
| BCG Challenged-Isoniazid Untreated | 0/5 (0%) | 1/5 (20%) | 5/5 (100%) |
| BCG Challenged-RIF Treated | 0/5 (0%) | 0/5 (0%) | 5/5 (100%) |
| BCG Challenged-Rifampin Untreated | 0/5 (0%) | 0/5 (0%) | 5/5 (100%) |
| Event | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Severe Back PainMusculoskeletal and connective tissue disorders | 0/5 | 1/5 | 0/5 | 0/5 |
| Event | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated |
|---|---|---|---|---|
| Injection site erythemaSkin and subcutaneous tissue disorders | 5/5 | 5/5 | 5/5 | 5/5 |
| Injection Site indurationSkin and subcutaneous tissue disorders | 5/5 | 5/5 | 5/5 | 5/5 |
| BCG Site AbscessSkin and subcutaneous tissue disorders | 0/5 | 0/5 | 0/5 | 1/5 |
| Age, Customized(years) | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated | Total |
|---|---|---|---|---|---|
| Median Age (Range) | 28 (20 to 36) | 40 (29 to 43) | 31 (21 to 41) | 36 (24 to 45) | 35 (20 to 45) |
| Sex/Gender, Customized(Participants) | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated | Total |
|---|---|---|---|---|---|
| Male | 3 | 3 | 2 | 3 | 11 |
| Female | 2 | 1 | 3 | 2 | 8 |
| Intersex | 0 | 1 | 0 | 0 | 1 |
| Ethnicity (NIH/OMB)(Participants) | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated | Total |
|---|---|---|---|---|---|
| Hispanic or Latino | 1 | 0 | 2 | 1 | 4 |
| Not Hispanic or Latino | 4 | 5 | 3 | 4 | 16 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | BCG Challenged-Isoniazid Treated | BCG Challenged-Isoniazid Untreated | BCG Challenged-RIF Treated | BCG Challenged-Rifampin Untreated | Total |
|---|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 | 0 | 0 |
| Asian | 0 | 0 | 1 | 0 | 1 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 |
| Black or African American | 0 | 1 | 0 | 0 | 1 |
| White | 4 | 4 | 0 | 4 | 12 |
| More than one race | 1 | 0 | 2 | 0 | 3 |
| Unknown or Not Reported | 0 | 0 | 2 | 1 | 3 |
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — Sharing de-identified AE's/SAE's from all individual participants with Merck \& Co during the trial.
Supporting information: Study protocol, Icf
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