A Phase 2 interventional study of Telacebec 300 mg and Telacebec 600 mg in Leprosy, Multibacillary, sponsored by Fondation Raoul Follereau. Not yet recruiting at 1 site in Benin. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by Fondation Raoul Follereau · Phase 2, Interventional, and Treatment
The goal of this clinical trail is to evaluate whether short-course telacebec-based regimens can induce rapid and measurable reductions in M. leprae viability, potentially establishing the foundation for future shorter, safer, and simplified therapeutic strategies for MB leprosy.
Participants will be randomised into one of the four study arms (A, B, C and D). The arm A is non interventional. For arms B, C, and D, the three-month study drug treatment will be followed by 9 months of MDT, bringing the total treatment time to 12 months. This provision of MDT ensures that the participant has received the recommended standard treatment for leprosy and is primarily for ethics considerations.
This is an open-label, randomised, controlled, multicentre phase II clinical trial conducted in Benin, Côte d'Ivoire and Ethiopia to evaluate the bactericidal efficacy of telacebec-based regimens in the treatment of multibacillary (MB) leprosy, with safety and tolerability as secondary objectives.
Participants who meet entry criteria and give consent will be randomised into four parallel groups: one control group (Group A) receiving standard WHO multidrug therapy (MDT); two investigational groups (Groups B and C) receiving telacebec monotherapy at two different dose levels; and one investigational group (Group D) receiving telacebec in combination with rifampicin. Upon completion of the assigned telacebec-based regimen, participants in Groups B, C, and D will subsequently receive standard WHO MDT.
Follow-up will be at least 12 months for all study arms; however, with the support of national programmes, patients may be followed for up to five years where possible.
Every fortnightly visit during the first three months (during which participants are taking study drugs) needs to be performed on the appointment day (±2 days). During post-IP treatment, once participants are on regular WHO MB-MDT, they are followed up on a monthly basis (-3/+2 days window). During the post-MDT period, they are followed up on a 3-monthly basis (±14 days window). The monthly dose of study medication must be taken as directly observed treatment (DOT) on the day of the visit. The Day 1 of the monthly WHO MB-MDT must also be taken as DOT.
The TEP is composed of clinicians experienced in the clinical management of leprosy, independent of the trial sites, and will provide assistance in reviewing the clinical response of participants included in the clinical trial. During the clinical follow-up, pictures of the lesions are taken systematically at every scheduled visit to document clinical evolution, identified with a code guaranteeing patient and treatment anonymity. After Day 84, pictures will be sent separately to each member of the TEP blinded to treatment allocation. The Technical Expert Panel (TEP) will give an independent assessment classifying each participant as showing clear improvement, moderate improvement, or no improvement.
At least three assessments from the TEP need to be collected for the decision. The decision will be taken by simple majority. If 4 out of 5 members provide an assessment and the decision is divided, a reserve list TEP member will be contacted.
52 studies on the registry are indexed under Leprosy; 13 are open to participants now.
This study's planned enrollment of 120 is above the median of 70 across 41 interventional studies indexed under Leprosy.
Browse Leprosy studies →This is the only study on the registry with Fondation Raoul Follereau as lead sponsor.
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.
Exclusion Criteria:
Other eligibility consideration -
All women of must be tested for pregnancy at screening, and again before dosing at baseline (Day 0) and on Days 28, 42, 56, and 84 of the experimental treatment phase. Women with a positive pregnancy test after enrolment will have their treatment shifted to MDT if randomised to a telacebec-containing arm.
All women of reproductive potential must use two reliable and effective methods of contraception simultaneously while taking the study medication and up to two months after the last dose of telacebec. One highly effective form of contraception must be used (hormonal, IUD, prior tubal ligation, or partner's prior vasectomy) plus one additional effective method (male latex or synthetic condom, diaphragm or cervical cap). Male participants whose female partners are of reproductive age must also use contraception for up to 90 days after the last telacebec dose.
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.
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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
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.
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.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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.
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.
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.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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.
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.
The World Health Organization recommends Multidrug Therapy (MDT) to cure leprosy. This standard treatment combines three medicines: (Rifampicin 300mg x 2) + (Clofazimin 100 mg x 3) + (Dapsone 50 mg) x 12 months
(Telacebec 100 mg x 3 once monthly x 3 months) followed by (Rifampicin 300mg x 2) + (Clofazimin 100 mg x 3) + (Dapsone 50 mg) x 12 months
Drug: Telacebec 300 mg
(Telacebec 100 mg x 6 once monthly x 3 months) followed by (Rifampicin 300mg x 2) + (Clofazimin 100 mg x 3) + (Dapsone 50 mg) x 12 months
Drug: Telacebec 600 mg
(Telacebec 100 mg x 3 + Rifampicin 300 mg x 2 once monthly x 3 months) followed by (Rifampicin 300mg x 2) + (Clofazimin 100 mg x 3) + (Dapsone 50 mg) x 12 months
Drug: Telacebec + Rifampicine
Telacebec 300 mg once monthly × 3 months
Telacebec 600 mg once monthly × 3 months
(Telacebec 300 mg + Rifampicine 600 mg) once monthly x 3 months
Change from baseline in viable Mycobacterium leprae load in participants' skin lesions
Treatment response of leprosy infection in each participant, measured in skin biopsies taken from the same lesion at baseline and Day 84 using the Molecular Viability Assay (MVA): quantitative RT-PCR of esxA and hsp18 transcripts, standardised to 3,000 bacilli. Reported as change in log10 viability; a larger decrease indicates a greater bactericidal effect of treatment in the participant. Arms B, C and D are compared with standard WHO MB-MDT (Arm A)
Time frame: Baseline (Day 0) and Day 84
Number of participants with treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs)
Clinical and laboratory adverse events, graded for severity and assessed for relationship to study drug, in participants receiving telacebec 300 mg, telacebec 600 mg, telacebec 300 mg + rifampicin 600 mg, or WHO MB-MDT
Time frame: From first dose through Day 84 (end of study drug period)
Proportion of participants with clinical improvement of leprosy skin lesions
Assessed with standardised lesion-response criteria based on clinical examination and standardised photographs, classified as clear, moderate or no improvement. Classification validated by an independent external expert panel.
Time frame: Day 84 and Month 12 (end of treatment)
Incidence and severity of leprosy reactions
Number of participants with Type 1 (reversal) reactions, defined by WHO criteria, and Type 2 reactions (erythema nodosum leprosum). ENL severity scored with the ENLIST ENL Severity Scale (EESS).
Time frame: Baseline through Month 24 (end of follow-up)
Change in peripheral nerve sensory function
Semmes-Weinstein monofilament thresholds at standardised sites of the hands and feet.
Time frame: Baseline, Day 84, Month 12, Month 24
Change in peripheral nerve motor function
Voluntary Muscle Testing (VMT) scores.
Time frame: Baseline, Day 84, Month 12, Month 24
Number of participants with new nerve function impairment
Time frame: Baseline through Month 24
Change in health-related quality of life (EQ-5D)
Time frame: Baseline, Day 84, Month 12
Participant-reported global impression of change (PGI-C)
Time frame: Day 84, Month 12
Proportion of participants with viable M. leprae in skin lesions
Skin biopsy material from a subset of participants (5 to 6 per group) are tested: Data reported per participant (presence of viable bacilli on day 84 compared to that participant's baseline sample).
Time frame: Baseline and Day 84
Change from baseline in M. leprae rRNA synthesis (RS) ratio in participants' skin lesions
Marker of ongoing bacterial replication in each participant's lesion
Time frame: Baseline and Day 84
Number of participants who discontinue or interrupt study treatment because of adverse events
Time frame: Throught Day 84
Number of participants with treatment-emergent laboratory abnormalities
Haematology, biochemistry and liver function tests
Time frame: Throught Day 84
Plasma concentration of telacebec in participants
Sparse pharmacokinetic sampling
Time frame: Day 0 through Day 84
Plan to share: Yes — The plan is not yet developed
No publications or documents are linked to this record.
Start is estimated for Dec 2026; primary completion for Nov 2028, 23 months later.
How these figures are worked out, and which studies are left out of them.
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 not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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