Trial Outcomes & Findings for TBTC Study 26 PK: Rifapentine Pharmacokinetics in Children During Treatment of Latent TB Infection (NCT NCT00164450)
NCT ID: NCT00164450
Last Updated: 2026-07-07
Results Overview
Rifapentine exposure was estimated in children and adults receiving once-weekly rifapentine plus isoniazid. A sparse sampling design used a plasma sample collected 24 hours after administration of study drugs.
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
158 participants
Primary outcome timeframe
24 hours after study-drug administration; AUC0-inf estimated using a nonlinear mixed-effects pharmacokinetic model incorporating the 24-hour rifapentine concentration, C24.
Results posted on
2026-07-07
Participant Flow
Participants were enrolled in a pharmacokinetic substudy of the PREVENT-TB trial evaluating once-weekly rifapentine plus isoniazid for treatment of latent tuberculosis infection.
A total of 158 participants were enrolled. One enrolled participant was not included in the pharmacokinetic analysis population. Participant Flow and Results are based on the 157 participants included in the pharmacokinetic substudy analysis.
Participant milestones
| Measure |
Adults, >18 Years
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
Children, 2 to <12 Years
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
|---|---|---|
|
Overall Study
STARTED
|
77
|
80
|
|
Overall Study
COMPLETED
|
75
|
79
|
|
Overall Study
NOT COMPLETED
|
2
|
1
|
Reasons for withdrawal
| Measure |
Adults, >18 Years
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
Children, 2 to <12 Years
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
|---|---|---|
|
Overall Study
Adverse Event
|
2
|
1
|
Baseline Characteristics
TBTC Study 26 PK: Rifapentine Pharmacokinetics in Children During Treatment of Latent TB Infection
Baseline characteristics by cohort
| Measure |
All Participants
n=157 Participants
Age was analyzed separately for pediatric and adult pharmacokinetic groups. Sex, race, and ethnicity data were available only for the combined pharmacokinetic study population and were not collected separately for pediatric and adult analysis groups. Therefore, these baseline measures are reported for all participants combined.
|
|---|---|
|
Age, Categorical
<=18 years
|
80 Participants
n=20 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
77 Participants
n=20 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=20 Participants
|
|
Sex: Female, Male
Female
|
76 Participants
n=20 Participants
|
|
Sex: Female, Male
Male
|
81 Participants
n=20 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
118 Participants
n=20 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
39 Participants
n=20 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=20 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=20 Participants
|
|
Race (NIH/OMB)
Asian
|
9 Participants
n=20 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=20 Participants
|
|
Race (NIH/OMB)
Black or African American
|
29 Participants
n=20 Participants
|
|
Race (NIH/OMB)
White
|
118 Participants
n=20 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=20 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=20 Participants
|
PRIMARY outcome
Timeframe: 24 hours after study-drug administration; AUC0-inf estimated using a nonlinear mixed-effects pharmacokinetic model incorporating the 24-hour rifapentine concentration, C24.Rifapentine exposure was estimated in children and adults receiving once-weekly rifapentine plus isoniazid. A sparse sampling design used a plasma sample collected 24 hours after administration of study drugs.
Outcome measures
| Measure |
Children, 2 to <12 Years
n=80 Participants
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
Adults, >18 Years
n=77 Participants
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
|---|---|---|
|
Rifapentine Area Under the Plasma Concentration-Time Curve From Time Zero to Infinity, AUC0-inf
|
650 mcg*h/mL
Interval 604.0 to 699.0
|
489 mcg*h/mL
Interval 451.0 to 529.0
|
PRIMARY outcome
Timeframe: 24 hours after study-drug administrationValue represents the coefficient of determination (R-squared) for the relationship between rifapentine C24 and AUC0-inf.
Outcome measures
| Measure |
Children, 2 to <12 Years
n=157 Participants
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
Adults, >18 Years
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
|---|---|---|
|
Correlation Between Rifapentine C24 and AUC0-inf
|
0.92 R-squared
|
—
|
SECONDARY outcome
Timeframe: 24 hours after study-drug administrationPopulation: Subgroup sample sizes for tablet administration method were not reported; total pediatric sample size (N=80) used for analysis population.
Comparison of rifapentine AUC0-inf between participants receiving crushed and whole rifapentine tablets.
Outcome measures
| Measure |
Children, 2 to <12 Years
n=80 Participants
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
Adults, >18 Years
n=80 Participants
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
|---|---|---|
|
Rifapentine AUC0-inf by Tablet Administration Method in Children
|
588 mcg*h/mL
Interval 538.0 to 643.0
|
809 mcg*h/mL
Interval 733.0 to 894.0
|
Adverse Events
Children, 2 to <12 Years
Serious events: 0 serious events
Other events: 5 other events
Deaths: 0 deaths
Adults, >18 Years
Serious events: 0 serious events
Other events: 13 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Children, 2 to <12 Years
n=80 participants at risk
Pediatric participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; rifapentine dose ranged from 300 mg to 900 mg based on weight. Children unable to swallow tablets received crushed rifapentine tablets in liquid or soft food.
|
Adults, >18 Years
n=77 participants at risk
Adult participants with latent tuberculosis infection enrolled in the pharmacokinetic substudy of PREVENT-TB. Participants received once-weekly rifapentine and isoniazid; adults received rifapentine 900 mg.
|
|---|---|---|
|
General disorders
Signs and symptoms
|
6.2%
5/80 • Number of events 5 • During the pharmacokinetic substudy / during 3HP treatment; signs or symptoms were also assessed in the 24 hours after study-drug administration. Confirm final AE collection period from the protocol or AE dataset.
Adverse events occurring within 24 hours after study-drug administration were assessed systematically. The available study data summarized these events as grade-1 signs or symptoms and did not include individual adverse event terms; therefore, adverse events are reported as a grouped category.
|
16.9%
13/77 • Number of events 13 • During the pharmacokinetic substudy / during 3HP treatment; signs or symptoms were also assessed in the 24 hours after study-drug administration. Confirm final AE collection period from the protocol or AE dataset.
Adverse events occurring within 24 hours after study-drug administration were assessed systematically. The available study data summarized these events as grade-1 signs or symptoms and did not include individual adverse event terms; therefore, adverse events are reported as a grouped category.
|
Additional Information
William R. Mac Kenzie, MD
Centers for Disease Control and Prevention (CDC), NCHHSTP/DTBE
Phone: 404 639-8123
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place