Novel Triple-dose Tuberculosis Retreatment Regimen (Tri-Do-Re)

April 10, 2025 updated by: Institute of Tropical Medicine, Belgium

Novel Triple-dose Tuberculosis Retreatment Regimen: How to Overcome Resistance Without Creating More in Niger

To determine if a high-dose first-line regimen is non-inferior (non-inferiority margin 10%) in terms of safety to the same regimen at regular dosing, in previously treated patients with rifampicin-susceptible recurrent Tuberculosis (TB).

Study Overview

Detailed Description

Stage 1: This is a pragmatic open-label multi-stage randomized clinical trial. Potential participants will be screened and enrolled in Damien Foundation (DF) clinics participating in the trial.

First we will perform a two-arm study with 6EHRZ as control arm and 6EH³R³Z as intervention arm. If at interim analysis the intervention arm is not considered to be non-inferior to the control arm, the intervention stops and enrolment will continue in a an adapted intervention arm and the control arm (6EHRZ). Otherwise, enrolment continues to 6EHRZ and 6EH³R³Z.

Observational study (stage 2): The DSMB members agreed due to safety concerns to continuing the study as a cohort with only the control arm. The control regimen will remain the same (6EHRZ).

As per routine practice, during treatment patients are in daily contact with the direct observed therapy (DOT) supervisor and minimally monthly clinic visits are scheduled for monitoring of safety and treatment response.

Additionally, liver function tests will be performed at fixed intervals during treatment. Six month and one year after treatment completion or cure the patient will be checked for relapse with systematic sputum acid-fast bacilli (AFB)-microscopy and TB culture.

Study Type

Interventional

Enrollment (Estimated)

370

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

  • Name: Natacha Herssens, MSc
  • Phone Number: 003232470778
  • Email: nherssens@itg.be

Study Contact Backup

  • Name: Tom Decroo, MD
  • Phone Number: 003232470535
  • Email: tdecroo@itg.be

Study Locations

      • Niamey, Niger
        • Recruiting
        • Damien Foundation
        • Contact:
        • Contact:
          • Sani Kadri

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • All newly registered patients with smear-positive recurrent pulmonary TB
  • Adults as well as children (no age limit)
  • Able and willing to provide written informed consent
  • Added for stage 2: lives within 5 km of a health facility with a medical doctor

Exclusion Criteria:

  • All patients with TB initially resistant to rifampicin on Xpert MTB/RIF testing
  • Patients transferred to a health facility not supported by the Damien Foundation
  • Patients previously enrolled in the trial, and with another episode of rifampicin-susceptible TB during the study period
  • Those with grade III elevation of liver function tests at baseline, or with clinically active liver disease at screening
  • Pregnant or breastfeeding woman
  • HIV co-infected patients requiring treatment with a protease inhibitor

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 6EH³R3Z
(Rifampicin (R)/ Isoniazid (H) / Pyrazinamide (Z)/Ethambutol (E)) 6-month high-dose treatment; New high-dose isoniazid / high-dose rifampicin retreatment regimen (6EH³R3Z) - that includes triple-dose rifampicin (R3; 30 mg/kg), and triple-dose isoniazid (H3; 15 mg/kg), complemented with pyrazinamide (Z) and ethambutol (E).

A triple dose is defined as the triple of the routine dose used for a specific WHO weight band. Hence, the mg/kg within a weigh-band varies, as is the case in routine practice.

Dosing takings into consideration the fixed dose combination (FDC) tablets (one tablet: 150 mg R + 75 mg H + 400 mg Z + 275mg E). Dosage relies on tables with dosage by weight-bands used by WHO for the Cat. 1 regimen. The dosage used for the intensive phase of the Cat. 1 regimen applies for the whole treatment duration. A double dose of H and R is added to the recommended normal dose for adults (WHO,2003)

Other Names:
  • Ethambutol; isoniazid; rifampicin; pyrazinamide
  • triple dose isoniazid
  • triple dose rifampicin
Active Comparator: 6EHRZ
Standard of care: 6-month 6RHZE regimen with dose combination tablets (one tablet: 150 mg R + 75 mg H + 400 mg Z + 275mg E)

Recommended normal dose adults (WHO, 2003)

  • H: 5 (4-6) mg/kg/day
  • R: 10 (8-12) mg/kg/day
  • Z: 25 (20-30)mg/kg/day
  • E: 15 (15-18)mg/kg/day
Other Names:
  • Ethambutol; isoniazid; rifampicin; pyrazinamide

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
STAGE 1:number of patients with any grade 3-5 Adverse Event (AE) during treatment, assessed as probably or definitely related to TB treatment
Time Frame: 18 months
18 months
STAGE 2: Describe bacterial effectiveness
Time Frame: 18 months
for stage 2 participants of the trial
18 months
STAGE 2: Describe acquired resistance
Time Frame: 18 months
for stage 2 participants of the trial
18 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
number of participants with stable (without reversion) SSM conversion
Time Frame: 2 months
conversion to 0 AFB per field, without subsequent treatment failure
2 months
STAGE 1: number of previously treated patients with H-monoresistance and H-polyresistance, rifampicin (RMP) resistance missed by Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF)
Time Frame: 18 months
frequency of initial resistance patterns and mutations conferring resistance
18 months
STAGE 1: Programmatical effectiveness:number of participants with treatment success divided by number of participants with failure, death, or Lost to follow-up (LTFU)
Time Frame: 6 months, 18 months
6 months treatment success: A patient with smear-positive Pulmonary Tuberculosis (PTB) at the beginning of treatment who completed treatment and sputum smear microscopy (SSM) negative in the last month of treatment and on at least one previous occasion or culture-negative at 6 months. A patient with smear-positive PTB at the beginning of treatment who completed treatment without clinical evidence of failure but with no record of sputum smear or culture results in the last month of treatment (either because tests were not done or because results are unavailable) 18 months treatment success: Those who were cured or completed treatment and were evaluated at 12 months post-treatment to be a) SSM negative , or b) SSM positive but culture (CU) negative, or c) without sputum and no clinical signs of TB.
6 months, 18 months
STAGE 1: Clinical effectiveness: number of participants with treatment success, divided by number of participants with failure or death
Time Frame: 6 months, 18 months
6 months treatment success: A patient with smear-positive PTB at the beginning of treatment who completed treatment and SSM negative in the last month of treatment and on at least one previous occasion or culture-negative at 6 months. A patient with smear-positive PTB at the beginning of treatment who completed treatment without clinical evidence of failure but with no record of sputum smear or culture results in the last month of treatment (either because tests were not done or because results are unavailable) 18 months treatment success: Those who were cured or completed treatment and were evaluated at 12 months post-treatment to be a) SSM negative , or b) SSM positive but CU negative, or c) without sputum and no clinical signs of TB.
6 months, 18 months
STAGE 1:Bacteriological effectiveness : number of participants with treatment success, divided by number of participants with failure
Time Frame: 6 months, 18 months
6 months treatment success: A patient with smear-positive PTB at the beginning of treatment who completed treatment and SSM negative in the last month of treatment and on at least one previous occasion or culture-negative at 6 months. A patient with smear-positive PTB at the beginning of treatment who completed treatment without clinical evidence of failure but with no record of sputum smear or culture results in the last month of treatment (either because tests were not done or because results are unavailable) 18 months treatment success: Those who were cured or completed treatment and were evaluated at 12 months post-treatment to be a) SSM negative , or b) SSM positive but CU negative, or c) without sputum and no clinical signs of TB.
6 months, 18 months
STAGE 2:Bacteriological effectiveness : number of participants with treatment success, divided by number of participants with failure
Time Frame: 6 months, 18 months
6 months treatment success: A patient with smear-positive PTB at the beginning of treatment who completed treatment and SSM negative in the last month of treatment and on at least one previous occasion or culture-negative at 6 months. A patient with smear-positive PTB at the beginning of treatment who completed treatment without clinical evidence of failure but with no record of sputum smear or culture results in the last month of treatment (either because tests were not done or because results are unavailable) 18 months treatment success: Those who were cured or completed treatment and were evaluated at 12 months post-treatment to be a) SSM negative , or b) SSM positive but CU negative, or c) without sputum and no clinical signs of TB.
6 months, 18 months
STAGE 2: number of participants with acquired resistance, to Isoniazid (INH) and/or RMP
Time Frame: 6 months, 18 months
In patients with recurrence, the recurrent strain will be compared with the diagnostic strain to identify possible differences in the resistance pattern. If the strain is the same, and resistance is not present in the diagnostic sample but is identified in the recurrence sample, then this resistance is considered as acquired. Resistance is defined as a) on genotypic Drug susceptibility testing (DST) (Deeplex or other): presence of a mutation in the resistance determining region for the drug with exception of generally recognized polymorphisms and silent mutations not leading to an error in the gene product. Heteroresistance at the proportion detectable by these methods will be considered at par with full-blown resistance, or b) growth at the critical concentration for the drug tested in phenotypic DST.
6 months, 18 months
STAGE 1: number of participants with drug-induced hepatotoxicity
Time Frame: 18 months

hepatotoxicity due to anti-TB drug treatment was defined as the following criteria:

  1. Grade 3-5 elevation of Liver function test (LFT), or grade 2 elevation of liver function tests with jaundice; AND
  2. absence of serological evidence of infection with hepatitis B or C, AND
  3. normalization or at least a 50% improvement in abnormal liver chemistry results after withdrawal of anti-TB drugs
18 months
STAGE 1:number of participants with any TB treatment change due to drug-induced hepatoxicity
Time Frame: 18 months
18 months
STAGE 1:number of participants with any TB treatment change due to AE
Time Frame: 18 months
18 months
STAGE 1:number of participants with any grade 3-5 AE
Time Frame: 18 months
18 months
STAGE 1:number of participants with any Serious Adverse Event (SAE)
Time Frame: 18 months
18 months
STAGE 2: number of participants with drug-induced hepatotoxicity
Time Frame: 18 months

hepatotoxicity due to anti-TB drug treatment was defined as the following criteria:

  1. Grade 3-5 elevation of Liver function test (LFT), or grade 2 elevation of liver function tests with jaundice; AND
  2. absence of serological evidence of infection with hepatitis B or C, AND
  3. normalization or at least a 50% improvement in abnormal liver chemistry results after withdrawal of anti-TB drugs
18 months
STAGE 2:number of participants with any TB treatment change due to drug-induced hepatoxicity
Time Frame: 18 months
18 months
STAGE 2:number of participants with any TB treatment change due to AE
Time Frame: 18 months
18 months
STAGE 2:number of participants with any grade 3-5 AE
Time Frame: 18 months
18 months
STAGE 2:number of participants with any Serious Adverse Event (SAE)
Time Frame: 18 months
18 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Principal Investigator: Sani Kadri, Ministry of Health, Niger

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 1, 2021

Primary Completion (Estimated)

June 1, 2025

Study Completion (Estimated)

September 1, 2025

Study Registration Dates

First Submitted

February 3, 2020

First Submitted That Met QC Criteria

February 5, 2020

First Posted (Actual)

February 7, 2020

Study Record Updates

Last Update Posted (Actual)

April 13, 2025

Last Update Submitted That Met QC Criteria

April 10, 2025

Last Verified

April 1, 2025

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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