A Phase 2 interventional study of Isoniazid and Rifampicin in Pulmonary Tuberculosis, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Suspended at 30 sites in 14 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Phase 2, Interventional, and Treatment
Temporarily Closed (Paused) to Accrual.
A5409/RAD-TB is an adaptive Phase 2 randomized, controlled, open-label, dose-ranging, platform protocol to evaluate the safety and efficacy of multidrug regimens for the treatment of adults with drug-susceptible pulmonary tuberculosis (TB).
A5409 hypothesizes that novel regimens for the treatment of pulmonary tuberculosis will result in superior early efficacy, as determined by longitudinal mycobacteria growth indicator tube (MGIT) liquid culture time to positivity (TTP) measurements over the first 6 weeks of treatment, and will have acceptable safety and tolerability over 8 weeks of treatment relative to standard of care [(SOC) isoniazid/rifampicin/pyrazinamide/ethambutol (HRZE)].
The study will run for 52 weeks, inclusive of 26 weeks of TB treatment comprised of 8 weeks of study treatment (experimental or SOC, based on treatment arm assignment) followed by 18 weeks of SOC continuation phase treatment with 346 participants in Wave 1: 49-50 participants in each experimental treatment arm and 98-100 participants in the SOC treatment arm.
319 studies on the registry are indexed under Tuberculosis, Pulmonary; 71 are open to participants now.
This study's planned enrollment of 341 is above the median of 146 across 227 interventional studies indexed under Tuberculosis, Pulmonary.
Browse Tuberculosis, Pulmonary studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.
Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Documentation of -1 infection status, as below:
Presence or absence of HIV-1 infection, as documented by:
The following laboratory values obtained within 7 days prior to study entry at any network-approved non-U.S. laboratory that operates in accordance with Good Clinical Laboratory Practices (GCLP) and participates in appropriate external quality assurance programs:
For female study candidates who are of , negative pregnancy test (urine HCG or serum β-HCG) within 3 days (72 hours) prior to entry by any network-approved non-U.S. laboratory or clinic that operates in accordance with GCLP and participates in appropriate external quality assurance programs.
Females who are of reproductive potential and who participate in sexual activity that could lead to pregnancy must agree to use at least two of the following forms of while receiving TB study medications and for 12 months after stopping study medications:
Female study candidates who are of reproductive potential, but who abstain from sexual activity that could lead to pregnancy require no additional contraception.
Female study candidates who are not of reproductive potential are eligible without requiring the use of contraceptives. Self-reported history is acceptable documentation of menopause (i.e., at least 1 year amenorrheic), hysterectomy, bilateral oophorectomy, or bilateral tubal ligation; these candidates are all considered not of reproductive potential.
For male study candidates who engage in sexual activity that may lead to pregnancy in their partner must agree to either remain abstinent or use male contraceptives. They are also strongly advised to inform their non-pregnant sexual partners of reproductive potential to use effective contraceptives while the individual is on study and for 90 days after experimental treatment discontinuation.
For male study candidates who have undergone successful vasectomy with documented azoospermia or have documented azoospermia for any other reason, are eligible without requiring the use of contraceptives.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CD4 count
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
* Weeks 1-8: INH 300 mg, RIF 600 mg, PZA weight-based, EMB weight-based * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Pyrazinamide · Drug: Ethambutol
* Weeks 1-8: BDQ 400 mg for 2 weeks and then 200 mg for 6 weeks, Pa 200 mg, LZD 600 mg * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Bedaquiline · Drug: Pretomanid · Drug: Linezolid
* Weeks 1-8: BDQ 400 mg for 2 weeks and then 200 mg for 6 weeks, Pa 200 mg, TBI-223 1200 mg * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Bedaquiline · Drug: Pretomanid · Drug: TBI-223
* Weeks 1-8: BDQ 400 mg for 2 weeks and then 200 mg for 6 weeks, Pa 200 mg, TBI-223 2400 mg * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Bedaquiline · Drug: Pretomanid · Drug: TBI-223
* Weeks 1-8: BDQ 400 mg for 2 weeks and then 200 mg for 6 weeks, Pa 200 mg, SZD 800 mg * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Bedaquiline · Drug: Pretomanid · Drug: Sutezolid
* Weeks 1-8: BDQ 400 mg for 2 weeks and then 200 mg for 6 weeks, Pa 200 mg, SZD 1600 mg * Weeks 9-26: INH 300 mg, RIF 600 mg (or weight-based dosing following WHO guidance)
Drug: Isoniazid · Drug: Rifampicin · Drug: Bedaquiline · Drug: Pretomanid · Drug: Sutezolid
INH 300 mg will be administered as one tablet orally once daily.
Also known as: INH
RIF 600 mg will be administered as two 300 mg capsules orally once daily on an empty stomach, 1 hour before or 2 hours after eating a meal.
Also known as: RIF
PZA will be administered as 500 mg tablets, based on weight, orally once daily.
Also known as: PZA
EMB will be administered as 400 mg tablets, based on weight, orally once daily.
Also known as: EMB
BDQ 400 mg will be administered as four 100 mg tablets orally once daily with a meal for the first 2 weeks followed by 200 mg (two 100 mg tablets) orally once daily with a meal for 6 weeks.
Also known as: BDQ
Pa 200 mg will be administered as one 200 mg tablet orally once daily with a meal.
Also known as: Pa
LZD 600 mg will be administered as one 600 mg tablet orally once daily.
Also known as: LZD
TBI-223 2400 mg once daily will be administered as four 600 mg tablets orally once daily with a meal.
SZD 1600 mg once daily will be administered as four 400 mg tablets orally once daily with a meal.
Also known as: SZD
TBI-223 1200 mg once daily will be administered as two 600 mg tablets orally with a meal.
SZD 800 mg once daily will be administered as two 400 mg tablets orally once daily with a meal.
Also known as: SZD
Difference in mean log10 (Time to positivity (TTP)) slope from longitudinal mycobacteria growth indicator tube (MGIT) liquid culture measurements over the first 6 weeks of treatment
for each experimental treatment arm compared to the SOC treatment arm.
Time frame: Weeks 0, 1, 2, 3, 4 and 6
Difference in the cumulative proportion of participants having at least one new Grade 3 or higher adverse event (AE) by week 8 of treatment
for each experimental treatment arm compared to the SOC treatment arm.
Time frame: 8 weeks
Cumulative proportion of participants with stable sputum culture conversion by week 8 as measured by culture-negative status via MGIT liquid culture at two consecutive measurements.
Time frame: 8 weeks
Mean log10 TTP slope from longitudinal MGIT liquid culture measurements over the first 8 weeks of treatment.
Time frame: Weeks 0, 1, 2, 3, 4, 6 and 8
Cumulative proportion of participants with a new Grade 3 or higher AE by week 26 of treatment.
Time frame: 26 weeks
Cumulative proportion of participants with permanent discontinuation of study-provided anti-TB drugs due to any reason prior to Week 8 of treatment.
Time frame: 8 weeks
Cumulative proportion of participants with permanent discontinuation or temporary discontinuation for ≥3 days of at least one anti-TB drug due to any reason prior to week 8 of treatment.
Time frame: 8 weeks
Cumulative proportion of participants with permanent discontinuation of at least one anti-TB drug due to any reason prior to week 26 of treatment.
Time frame: 26 weeks
A composite of stable culture conversion at week 6 of treatment and no new Grade 3 or higher AE through week 8.
Time frame: 8 weeks
Proportion of participants with durable cure by 52 weeks after treatment initiation.
Time frame: 52 Weeks
Plan to share: Yes — Individual participant data that underlie results in the publication, after deidentification.
Time frame: Beginning 3 months following publication and available throughout period of funding of the AIDS Clinical Trials Group by NIH.
Access criteria: With whom? Researchers who provide a methodologically sound proposal for use of the data that is approved by the AIDS Clinical Trials Group. For what types of analyses? To achieve aims in the proposal approved by the AIDS Clinical Trials Group. By what mechanism will data be made available? Researchers may submit a request for access to data using the AIDS Clinical Trials Group "Data Request" form at: https://actgnetwork.org/submit-a-proposal/. Researchers of approved proposals will need to sign an AIDS Clinical Trials Group Data Use Agreement before receiving the data.
Temporarily Closed (Paused) to Accrual.
Temporarily Closed (Paused) to Accrual.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is suspended, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drugs tested here: Bedaquiline · Pretomanid · Linezolid · TBI-223 · PNU-100480
National Institute of Allergy and Infectious Diseases (NIAID) →