Bedaquiline-pretomanid-moxifloxacin-pyrazinamide for drug-sensitive and drug-resistant pulmonary tuberculosis treatment: a phase 2c, open-label, multicentre, partially randomised controlled trial.

BACKGROUND: The current tuberculosis (TB) drug development pipeline is being re-populated with candidates, including nitroimidazoles such as pretomanid, that exhibit a potential to shorten TB therapy by exerting a bactericidal effect on non-replicating bacilli. Based on results from preclinical and early clinical studies, a four-drug combination of bedaquiline, pretomanid, moxifloxacin, and pyrazinamide (BPaMZ) regimen was identified with treatment-shortening potential for both drug-susceptible (DS) and drug-resistant (DR) TB. This trial aimed to determine the safety and efficacy of BPaMZ. We compared 4 months of BPaMZ to the standard 6 months of isoniazid, rifampicin, pyrazinamide, and ethambutol (HRZE) in DS-TB. 6 months of BPaMZ was assessed in DR-TB. METHODS: SimpliciTB was a partially randomised, phase 2c, open-label, clinical trial, recruiting participants at 26 sites in eight countries. Participants aged 18 years or older with pulmonary TB who were sputum smear positive for acid-fast bacilli were eligible for enrolment. Participants with DS-TB had Mycobacterium tuberculosis with sensitivity to rifampicin and isoniazid. Participants with DR-TB had M tuberculosis with resistance to rifampicin, isoniazid, or both. Participants with DS-TB were randomly allocated in a 1:1 ratio, stratified by HIV status and cavitation on chest radiograph, using balanced block randomisation with a fixed block size of four. The primary efficacy endpoint was time to sputum culture-negative status by 8 weeks; the key secondary endpoint was unfavourable outcome at week 52. A non-inferiority margin of 12% was chosen for the key secondary outcome. Safety and tolerability outcomes are presented as descriptive analyses. The efficacy analysis population contained patients who received at least one dose of medication and who had efficacy data available and had no major protocol violations. The safety population contained patients who received at least one dose of medication. This study is registered with ClinicalTrials.gov (NCT03338621) and is completed. FINDINGS: Between July 30, 2018, and March 2, 2020, 455 participants were enrolled and received at least one dose of study treatment. 324 (71%) participants were male and 131 (29%) participants were female. 303 participants with DS-TB were randomly assigned to 4 months of BPaMZ (n=150) or HRZE (n=153). In a modified intention-to-treat (mITT) analysis, by week 8, 122 (84%) of 145 and 70 (47%) of 148 participants were culture-negative on 4 months of BPaMZ and HRZE, respectively, with a hazard ratio for earlier negative status of 2·93 (95% CI 2·17-3·96; p<0·0001). Median time to negative culture (TTN) was 6 weeks (IQR 4-8) on 4 months of BPaMZ and 11 weeks (6-12) on HRZE. 86% of participants with DR-TB receiving 6 months of BPaMZ (n=152) reached culture-negative status by week 8, with a median TTN of 5 weeks (IQR 3-7). At week 52, 120 (83%) of 144, 134 (93%) of 144, and 111 (83%) of 133 on 4 months of BPaMZ, HRZE, and 6 months of BPaMZ had favourable outcomes, respectively. Despite bacteriological efficacy, 4 months of BPaMZ did not meet the non-inferiority margin for the key secondary endpoint in the pre-defined mITT population due to higher withdrawal rates for adverse hepatic events. Non-inferiority was demonstrated in the per-protocol population confirming the effect of withdrawals with 4 months of BPaMZ. At least one liver-related treatment-emergent adverse effect (TEAE) occurred among 45 (30%) participants on 4 months of BPaMZ, 38 (25%) on HRZE, and 33 (22%) on 6 months of BPaMZ. Serious liver-related TEAEs were reported by 20 participants overall; 11 (7%) among those on 4 months of BPaMZ, one (1%) on HRZE, and eight (5%) on 6 months of BPaMZ. The most common reasons for discontinuation of trial treatment were hepatotoxicity (ten participants [2%]), increased hepatic enzymes (nine participants [2%]), QTcF prolongation (three participants [1%]), and hypersensitivity (two participants [<1%]). INTERPRETATION: For DS-TB, BPaMZ successfully met the primary efficacy endpoint of sputum culture conversion. The regimen did not meet the key secondary efficacy endpoint due to adverse events resulting in treatment withdrawal. Our study demonstrated the potential for treatment-shortening efficacy of the BPaMZ regimen for DS-TB and DR-TB, providing clinical validation of a murine model widely used to identify such regimens. It also highlights that novel, treatment-shortening TB treatment regimens require an acceptable toxicity and tolerability profile with minimal monitoring in low-resource and high-burden settings. The increased risk of unpredictable severe hepatic adverse events with 4 months of BPaMZ would be a considerable obstacle to implementation of this regimen in settings with high burdens of TB with limited infrastructure for close surveillance of liver biochemistry. Future research should focus on improving the preclinical and early clinical detection and mitigation of safety issues together and further efforts to optimise shorter treatments. FUNDING: TB Alliance.

Patients' priorities around drug-resistant tuberculosis treatment: A multi-national qualitative study from Mongolia, South Africa and Georgia.

We conducted qualitative research exploring the treatment experience of people with DR-TB. We held nine focus group discussions with 57 adults undergoing/recently completed treatment for DR-TB in Georgia, Mongolia and South Africa. Translated transcripts were analysed using thematic analysis. We identified three higher order themes: (1) Treatment experience and the role of good relationships with healthcare providers: Treatment duration, pill burden and side-effects were challenging aspects of treatment. Side-effects/symptoms that were visible signs of illness were particularly troubling. Good relations with clinical staff helped combat fear and uncertainty regarding treatment. (2) Mental distress and opportunities for wellbeing: The shame, stigma and isolation people experienced as a result of their DR-TB diagnosis was an important cause of mental distress. No longer being infectious enabled people to resume work and socialising. Positive emotions emerged with good treatment outcomes. (3) Fear and worry along the treatment journey: Participants expressed fears about TB: infecting others; whether they would be able to endure treatment; side-effects; health consequences of treatment. Worries mostly disappeared with successful treatment. Alongside measuring side-effects, time to culture conversion and cure rates, future trials of DR-TB treatments should capture how quickly visible symptoms resolve, quality of life measures, and mental health outcomes.

Cost-effectiveness of new MDR-TB regimens: study protocol for the TB-PRACTECAL economic evaluation substudy.

INTRODUCTION: Current treatment regimens for multidrug-resistant tuberculosis (MDR-TB) are long, poorly tolerated and have poor outcomes. Furthermore, the costs of treating MDR-TB are much greater than those for treating drug-susceptible TB, both for health service and patient-incurred costs. Urgent action is needed to identify short, effective, tolerable and cheaper treatments for people with both quinolone-susceptible and quinolone-resistant MDR-TB. We present the protocol for an economic evaluation (PRACTECAL-EE substudy) alongside an ongoing clinical trial (TB-PRACTECAL) aiming to assess the costs to patients and providers of new regimens, as well as their cost-effectiveness and impact on participant poverty levels. This substudy is based on data from the three countries participating in the main trial. METHODS AND ANALYSIS: Primary cost data will be collected from the provider and patient perspectives, following economic best practice. We will estimate the probability that new MDR-TB regimens containing bedaquiline, pretomanid and linezolid are cost-effective from a societal perspective as compared with the standard of care for MDR-TB patients in Uzbekistan, South Africa and Belarus. Analysis uses a Markov model populated with primary cost and outcome data collected at each study site. We will also estimate the impact of new regimens on prevalence of catastrophic patient costs due to TB. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the London School of Hygiene & Tropical Medicine and Médecins Sans Frontières. Local ethical approval will be sought in each study site. The results of the economic evaluation will be shared with the country health authorities and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04207112); Pre-results.

Efficacy and safety of delamanid in combination with an optimised background regimen for treatment of multidrug-resistant tuberculosis: a multicentre, randomised, double-blind, placebo-controlled, parallel group phase 3 trial.

BACKGROUND: Delamanid is one of two recently approved drugs for the treatment of multidrug-resistant tuberculosis. We aimed to evaluate the safety and efficacy of delamanid in the first 6 months of treatment. METHODS: This randomised, double-blind, placebo-controlled, phase 3 trial was done at 17 sites in seven countries (Estonia, Latvia, Lithuania, Moldova, Peru, the Philippines, and South Africa). We enrolled eligible adults (>18 years) with pulmonary multidrug-resistant tuberculosis to receive, in combination with an optimised background regimen developed according to WHO and national guidelines, either oral delamanid (100 mg twice daily) for 2 months followed by 200 mg once daily for 4 months or placebo (same regimen). Patients were centrally randomised (2:1) and stratified by risk category for delayed sputum culture conversion. Primary outcomes were the time to sputum culture conversion over 6 months and the difference in the distribution of time to sputum culture conversion over 6 months between the two groups, as assessed in the modified intention-to-treat population. The trial is registered at ClinicalTrials.gov, number NCT01424670. FINDINGS: Between Sept 2, 2011, and Nov 27, 2013, we screened 714 patients, of whom 511 were randomly assigned (341 to delamanid plus optimised background regimen [delamanid group] and 170 to placebo plus optimised background regimen [placebo group]) and formed the safety analysis population. 327 patients were culture-positive for multidrug-resistant tuberculosis at baseline and comprised the efficacy analysis population (226 in the delamanid group and 101 in the placebo group). Median time to sputum culture conversion did not differ between the two groups (p=0·0562; modified Peto-Peto), with 51 days (IQR 29-98) in the delamanid group and 57 days (43-85) in the placebo group; the hazard ratio was 1·17 (95% CI 0·91-1·51, p=0·2157). 501 (98·0%) of 511 patients had at least one treatment-emergent adverse event. 136 (26·6%) of 511 patients had at least one serious treatment-emergent adverse event; the incidence was similar between treatment groups (89 [26·1%] of 341 patients for delamanid and 47 [27·6%] of 170 for placebo). Deaths related to treatment-emergent adverse events were similar between groups (15 [4·4%] of 341 for delamanid and six [3·5%] of 170 for placebo). No deaths were considered to be related to delamanid. INTERPRETATION: The reduction in median time to sputum culture conversion over 6 months was not significant in the primary analysis. Delamanid was well tolerated with a highly characterised safety profile. Further evaluation of delamanid is needed to determine its role in a rapidly evolving standard of care. FUNDING: Otsuka Pharmaceutical.

Bedaquiline, moxifloxacin, pretomanid, and pyrazinamide during the first 8 weeks of treatment of patients with drug-susceptible or drug-resistant pulmonary tuberculosis: a multicentre, open-label, partially randomised, phase 2b trial.

BACKGROUND: New anti-tuberculosis regimens that are shorter, simpler, and less toxic than those that are currently available are needed as part of the global effort to address the tuberculosis epidemic. We aimed to investigate the bactericidal activity and safety profile of combinations of bedaquiline, pretomanid, moxifloxacin, and pyrazinamide in the first 8 weeks of treatment of pulmonary tuberculosis. METHODS: In this multicentre, open-label, partially randomised, phase 2b trial, we prospectively recruited patients with drug-susceptible or rifampicin-resistant pulmonary tuberculosis from seven sites in South Africa, two in Tanzania, and one in Uganda. Patients aged 18 years or older with sputum smear grade 1+ or higher were eligible for enrolment, and a molecular assay (GeneXpert or MTBDRplus) was used to confirm the diagnosis of tuberculosis and to distinguish between drug-susceptible and rifampicin-resistant tuberculosis. Patients who were HIV positive with a baseline CD4 cell count of less than 100 cells per uL were excluded. Patients with drug-susceptible tuberculosis were randomly assigned (1:1:1) using numbered treatment packs with sequential allocation by the pharmacist to receive 56 days of treatment with standard tuberculosis therapy (oral isoniazid, rifampicin, pyrazinamide, and ethambutol; HRZE), or pretomanid (oral 200 mg daily) and pyrazinamide (oral 1500 mg daily) with either oral bedaquiline 400 mg daily on days 1-14 then 200 mg three times per week (BloadPaZ) or oral bedaquiline 200 mg daily (B200PaZ). Patients with rifampicin-resistant tuberculosis received 56 days of the B200PaZ regimen plus moxifloxacin 400 mg daily (BPaMZ). All treatment groups were open label, and randomisation was not stratified. Patients, trial investigators and staff, pharmacists or dispensers, laboratory staff (with the exception of the mycobacteriology laboratory staff), sponsor staff, and applicable contract research organisations were not masked. The primary efficacy outcome was daily percentage change in time to sputum culture positivity (TTP) in liquid medium over days 0-56 in the drug-susceptible tuberculosis population, based on non-linear mixed-effects regression modelling of log10 (TTP) over time. The efficacy analysis population contained patients who received at least one dose of medication and who had efficacy data available and had no major protocol violations. The safety population contained patients who received at least one dose of medication. This study is registered with ClinicalTrials.gov, NCT02193776, and all patients have completed follow-up. FINDINGS: Between Oct 24, 2014, and Dec 15, 2015, we enrolled 180 patients with drug-susceptible tuberculosis (59 were randomly assigned to BloadPaZ, 60 to B200PaZ, and 61 to HRZE) and 60 patients with rifampicin-resistant tuberculosis. 57 patients in the BloadPaZ group, 56 in the B200PaZ group, and 59 in the HRZE group were included in the primary analysis. B200PaZ produced the highest daily percentage change in TTP (5·17% [95% Bayesian credibility interval 4·61-5·77]), followed by BloadPaZ (4·87% [4·31-5·47]) and HRZE group (4·04% [3·67-4·42]). The bactericidal activity in B200PaZ and BloadPaZ groups versus that in the HRZE group was significantly different. Higher proportions of patients in the BloadPaZ (six [10%] of 59) and B200PaZ (five [8%] of 60) groups discontinued the study drug than in the HRZE group (two [3%] of 61) because of adverse events. Liver enzyme elevations were the most common grade 3 or 4 adverse events and resulted in the withdrawal of ten patients (five [8%] in the BloadPaZ group, three [5%] in the B200PaZ group, and two [3%] in the HRZE group). Serious treatment-related adverse events affected two (3%) patients in the BloadPaZ group and one (2%) patient in the HRZE group. Seven (4%) patients with drug-susceptible tuberculosis died and four (7%) patients with rifampicin-resistant tuberculosis died. None of the deaths were considered to be related to treatment. INTERPRETATION: B200PaZ is a promising regimen to treat patients with drug-susceptible tuberculosis. The bactericidal activity of both these regimens suggests that they have the potential to shorten treatment, and the simplified dosing schedule of B200PaZ could improve treatment adherence in the field. However, these findings must be investigated further in a phase 3 trial assessing treatment outcomes. FUNDING: TB Alliance, UK Department for International Development, Bill & Melinda Gates Foundation, US Agency for International Development, Directorate General for International Cooperation of the Netherlands, Irish Aid, Australia Department of Foreign Affairs and Trade, and the Federal Ministry for Education and Research of Germany.