BACKGROUND Around 500,000 people worldwide develop rifampicin-resistant tuberculosis each year. The proportion of successful treatment outcomes remains low and new treatments are needed. Following an interim analysis, we report the final safety and efficacy outcomes of the TB-PRACTECAL trial, evaluating the safety and efficacy of oral regimens for the treatment of rifampicin-resistant tuberculosis.
METHODS This open-label, randomised, controlled, multi-arm, multicentre, non-inferiority trial was conducted at seven hospital and community sites in Uzbekistan, Belarus, and South Africa, and enrolled participants aged 15 years and older with pulmonary rifampicin-resistant tuberculosis. Participants were randomly assigned, in a 1:1:1:1 ratio using variable block randomisation and stratified by trial site, to receive 36-80 week standard care; 24-week oral bedaquiline, pretomanid, and linezolid (BPaL); BPaL plus clofazimine (BPaLC); or BPaL plus moxifloxacin (BPaLM) in stage one of the trial, and in a 1:1 ratio to receive standard care or BPaLM in stage two of the trial, the results of which are described here. Laboratory staff and trial sponsors were masked to group assignment and outcomes were assessed by unmasked investigators. The primary outcome was the percentage of participants with a composite unfavourable outcome (treatment failure, death, treatment discontinuation, disease recurrence, or loss to follow-up) at 72 weeks after randomisation in the modified intention-to-treat population (all participants with rifampicin-resistant disease who received at least one dose of study medication) and the per-protocol population (a subset of the modified intention-to-treat population excluding participants who did not complete a protocol-adherent course of treatment (other than because of treatment failure or death) and those who discontinued treatment early because they violated at least one of the inclusion or exclusion criteria). Safety was measured in the safety population. The non-inferiority margin was 12%. This trial is registered with ClinicalTrials.gov, NCT02589782, and is complete.
FINDINGS Between Jan 16, 2017, and March 18, 2021, 680 patients were screened for eligibility, of whom 552 were enrolled and randomly assigned (152 to the standard care group, 151 to the BPaLM group, 126 to the BPaLC group, and 123 to the BPaL group). The standard care and BPaLM groups proceeded to stage two and are reported here, post-hoc analyses of the BPaLC and BPaL groups are also reported. 151 participants in the BPaLM group and 151 in the standard care group were included in the safety population, with 138 in the BPaLM group and 137 in the standard care group in the modified intention-to-treat population. In the modified intention-to-treat population, unfavourable outcomes were reported in 16 (12%) of 137 participants for whom outcome was assessable in the BPaLM group and 56 (41%) of 137 participants in the standard care group (risk difference -29·2 percentage points [96·6% CI -39·8 to -18·6]; non-inferiority and superiority p<0·0001). 34 (23%) of 151 participants receiving BPaLM had adverse events of grade 3 or higher or serious adverse events, compared with 72 (48%) of 151 participants receiving standard care (risk difference -25·2 percentage points [96·6% CI -36·4 to -13·9]). Five deaths were reported in the standard care group by week 72, of which one (COVID-19 pneumonia) was unrelated to treatment and four (acute pancreatitis, suicide, sudden death, and sudden cardiac death) were judged to be treatment-related.
INTERPRETATION The 24-week, all-oral BPaLM regimen is safe and efficacious for the treatment of pulmonary rifampicin-resistant tuberculosis, and was added to the WHO guidance for treatment of this condition in 2022. These findings will be key to BPaLM becoming the preferred regimen for adolescents and adults with pulmonary rifampicin-resistant tuberculosis. More
N Engl J Med. 2022 December 22; Volume 387 (Issue 25); 2331-2343.
Nyang'wa BT, Berry C, Kazounis E, Motta I, Parpieva N, et al.
N Engl J Med. 2022 December 22; Volume 387 (Issue 25); 2331-2343.
BACKGROUND In patients with rifampin-resistant tuberculosis, all-oral treatment regimens that are more effective, shorter, and have a more acceptable side-effect profile than current regimens are needed.
METHODS We conducted an open-label, phase 2–3, multicenter, randomized, controlled, noninferiority trial to evaluate the efficacy and safety of three 24-week, all-oral regimens for the treatment of rifampin-resistant tuberculosis. Patients in Belarus, South Africa, and Uzbekistan who were 15 years of age or older and had rifampin-resistant pulmonary tuberculosis were enrolled. In stage 2 of the trial, a 24-week regimen of bedaquiline, pretomanid, linezolid, and moxifloxacin (BPaLM) was compared with a 9-to-20-month standard-care regimen. The primary outcome was an unfavorable status (a composite of death, treatment failure, treatment discontinuation, loss to follow-up, or recurrence of tuberculosis) at 72 weeks after randomization. The noninferiority margin was 12 percentage points.
RESULTS Recruitment was terminated early. Of 301 patients in stage 2 of the trial, 145, 128, and 90 patients were evaluable in the intention-to-treat, modified intention-to-treat, and per-protocol populations, respectively. In the modified intention-to-treat analysis, 11% of the patients in the BPaLM group and 48% of those in the standard-care group had a primary-outcome event (risk difference, -37 percentage points; 96.6% confidence interval [CI], -53 to -22). In the per-protocol analysis, 4% of the patients in the BPaLM group and 12% of those in the standard-care group had a primary-outcome event (risk difference, -9 percentage points; 96.6% CI, -22 to 4). In the as-treated population, the incidence of adverse events of grade 3 or higher or serious adverse events was lower in the BPaLM group than in the standard-care group (19% vs. 59%).
CONCLUSIONS In patients with rifampin-resistant pulmonary tuberculosis, a 24-week, all-oral regimen was noninferior to the accepted standard-care treatment, and it had a better safety profile. (Funded by Médecins sans Frontières; TB-PRACTECAL ClinicalTrials.gov number, NCT02589782. opens in new tab.)More
PLOS Glob Public Health. 2022 December 7; Volume 2 (Issue 12); e0001337.
Sweeney S, Berry C, Kazounis E, Motta I, Vassall A, et al.
PLOS Glob Public Health. 2022 December 7; Volume 2 (Issue 12); e0001337.
Current options for treating tuberculosis (TB) that is resistant to rifampicin (RR-TB) are few, and regimens are often long and poorly tolerated. Following recent evidence from the TB-PRACTECAL trial countries are considering programmatic uptake of 6-month, all-oral treatment regimens. We used a Markov model to estimate the incremental cost-effectiveness of three regimens containing bedaquiline, pretomanid and linezolid (BPaL) with and without moxifloxacin (BPaLM) or clofazimine (BPaLC) compared with the current mix of long and short standard of care (SOC) regimens to treat RR-TB from the provider perspective in India, Georgia, Philippines, and South Africa. We estimated total costs (2019 USD) and disability-adjusted life years (DALYs) over a 20-year time horizon. Costs and DALYs were discounted at 3% in the base case. Parameter uncertainty was tested with univariate and probabilistic sensitivity analysis. We found that all three regimens would improve health outcomes and reduce costs compared with the current programmatic mix of long and short SOC regimens in all four countries. BPaL was the most cost-saving regimen in all countries, saving $112-$1,173 per person. BPaLM was the preferred regimen at a willingness to pay per DALY of 0.5 GDP per capita in all settings. Our findings indicate BPaL-based regimens are likely to be cost-saving and more effective than the current standard of care in a range of settings. Countries should consider programmatic uptake of BPaL-based regimens.More
Berry C, du Cros PAK, Fielding K, Gajewski S, Kazounis E, et al.
Trials. 2022 June 13; Volume 23 (Issue 1); 484.
BACKGROUND Globally rifampicin-resistant tuberculosis disease affects around 460,000 people each year. Currently recommended regimens are 9-24 months duration, have poor efficacy and carry significant toxicity. A shorter, less toxic and more efficacious regimen would improve outcomes for people with rifampicin-resistant tuberculosis.
METHODS TB-PRACTECAL is an open-label, randomised, controlled, phase II/III non-inferiority trial evaluating the safety and efficacy of 24-week regimens containing bedaquiline and pretomanid to treat rifampicin-resistant tuberculosis. Conducted in Uzbekistan, South Africa and Belarus, patients aged 15 and above with rifampicin-resistant pulmonary tuberculosis and requiring a new course of therapy were eligible for inclusion irrespective of HIV status. In the first stage, equivalent to a phase IIB trial, patients were randomly assigned one of four regimens, stratified by site. Investigational regimens include oral bedaquiline, pretomanid and linezolid. Additionally, two of the regimens also included moxifloxacin (arm 1) and clofazimine (arm 2) respectively. Treatment was administered under direct observation for 24 weeks in investigational arms and 36 to 96 weeks in the standard of care arm. The second stage of the study was equivalent to a phase III trial, investigating the safety and efficacy of the most promising regimen/s. The primary outcome was the percentage of unfavourable outcomes at 72 weeks post-randomisation. This was a composite of early treatment discontinuation, treatment failure, recurrence, lost-to-follow-up and death. The study is being conducted in accordance with ICH-GCP and full ethical approval was obtained from Médecins sans Frontières ethical review board, London School of Hygiene and Tropical Medicine ethical review board as well as ERBs and regulatory authorities at each site.
DISCUSSION TB-PRACTECAL is an ambitious trial using adaptive design to accelerate regimen assessment and bring novel treatments that are effective and safe to patients quicker. The trial took a patient-centred approach, adapting to best practice guidelines throughout recruitment. The implementation faced significant challenges from the COVID-19 pandemic. The trial was terminated early for efficacy on the advice of the DSMB and will report on data collected up to the end of recruitment and, additionally, the planned final analysis at 72 weeks after the end of recruitment.More
Lachenal N, Hewison CCH, Berry C, Mitnick CD, Ahmed SM, et al.
MSF Scientific Days International 2022. 2022 May 11
INTRODUCTION Drug-resistant tuberculosis (DR-TB) carries significant morbidity and mortality risk. Care of DR-TB in pregnancy is even more challenging. A recent meta-analysis examining the impact of DR-TB on pregnancy outcomes found a higher than expected rate of maternal death, pregnancy loss, and a significant prevalence of low-birthweight infants. Anti-tubercular drugs such as bedaquiline and clofazimine have long half-lives and the impact of in-utero exposure is largely unknown. There is little information to help women, their family members, and clinicians make informed decisions about DR-TB treatment during pregnancy.
METHODS Data on pregnancy outcomes were systematically collected as part of a pharmacovigilance programme supporting a clinical trial (TB-PRACTECAL; N=552) and a prospective cohort (endTB; N=2,906). We present the birth outcomes as reported to investigators by participants.
ETHICS The endTB and TB-PRACTECAL studies were both approved by the local ethics committees in all recruiting countries and by the MSF Ethics Review Board. endTB was approved by the Partners Healthcare Human Research Committee, Boston, USA, and TB-PRACTECAL was approved by the London School of Hygiene and Tropical Medicine Ethics Committee, UK.
RESULTS Between 01 April 2015 and 31 December 2021, 58 pregnancies in 53 women were notified from 10 different countries, predominantly Uzbekistan (14), Kazakhstan (13) and Pakistan (9). In 13 cases, pregnancy occurred after completion of tuberculosis treatment. Patients became pregnant a median of 260.5 (range, 0-727) days from treatment start; five women were 5-32 weeks pregnant at treatment start. There were no maternal deaths. 17.0% (9/53) of mothers changed or interrupted treatment during pregnancy. Treatment outcome was successful in 97.3% (36/37) of others in endTB and 100% (7/7) of mothers who completed follow-up in TB-PRACTECAL. Pregnancy outcome was known in 52 cases: 20 elective abortions, three miscarriages and 30 live births (one twin pregnancy). There were no stillbirths. Of the 30 live births, 29 occurred in mothers ever exposed to bedaquiline, 16 to clofazimine, 11 to a second-line injectable, 10 to pretomanid, and 7 to delamanid. Birth weight was known in 24/30 (80.0%) babies. Median weight was 3,015 (range, 1,270 to 4,200) grams. Two babies were born prematurely at 30 and 31 weeks. Low birthweight was reported in seven (29.2%; 7/24) babies. One low-birthweight baby died within four months of birth from complications unrelated to tuberculosis. One baby was treated for DR-TB. There were no reported birth malformations.
CONCLUSION These results support evidence that effective DR-TB treatments may improve maternal outcomes and prevent perinatal transmission. How these perinatal outcomes compare to other cohorts not affected by TB in these settings or exposed to different TB treatments needs exploration. The factors contributing to low birthweight in babies born to mothers with DR-TB requires further research. A global registry is urgently needed to assist parents and clinicians with decision-making.
CONFLICTS OF INTEREST The endTB project was funded by UNITAID (Geneva, Switzerland). Provision of delamanid within the endTB project was partially funded through a donation from Otsuka Company (Kyoto, Japan).More
Berry C, Motta I, Kazounis E, Fielding K, Dodd M, et al.
MSF Scientific Days International 2022. 2022 May 11
INTRODUCTION Rifamipcin-resistant tuberculosis (RR-TB) affects around 465,000 people each year globally. Current treatment is of 9-20 months’ duration; is toxic and poorly efficacious. TB-PRACTECAL is a multi-arm, 2-stage, randomised controlled, multi-country, non-inferiority trial comparing 24-week regimens to the locally approved standard of care (control). We report TB-PRACTECAL stage 1 and 2 outcomes as well as additional analyses from dropped arms.
METHODS Participants 15 years and above with pulmonary RR-TB from Uzbekistan, South Africa, and Belarus were included regardless of HIV status or CD4 count. Patients were randomized in a 1:1:1:1 ratio in stage 1 and 1:1 in stage 2. Randomization lists were stratified according to trial site. The BPaL regimen was comprised of bedaquiline 400mg daily for 2 weeks then 200mg three times weekly for 22 weeks, pretomanid 200mg daily for 24 weeks, and linezolid 600mg daily for 16 weeks followed by 300mg daily for 8 weeks. BPaLM additionally contained moxifloxacin 400mg daily and BPaLC contained clofazimine 100mg daily. Treatment was administered daily under observation. Transition to stage 2 occurred after enrolment of 240 participants and BPaLM was found to be the most promising arm. Randomisation continued during transition and all participants continued their allocated regimen and were followed up to 108 weeks. A post-hoc analysis was conducted comparing the three investigational arms to control using the primary efficacy outcome: proportion of patients with unfavourable outcome (death, treatment discontinuation, treatment failure, recurrence, lost to follow-up) at 72 weeks. We also assessed the proportion of patients with grade =3 or serious adverse events (SAE) by 72 weeks and mean change in QT corrected using Fridericia’s formula (QTcF) at week 24.
ETHICS This study was approved by the Ethics Review Board (ERB) of the London School of Hygiene and Tropical Medicine and the local ERBs in Uzbekistan, Belarus and South Africa; and by the MSF ERB.
RESULTS In March 2021, TB-PRACTECAL was terminated for efficacy at which point, 552 patients were enrolled. In the modified intention-to-treat population (comprising all randomised patients dispensed study medication at least once, excluding patients who did not have microbiologically-proven RR-TB), 252 patients had reached 72 weeks of follow-up, 44.0% of whom were female and 22.6% were HIV positive. In the modified intention- to-treat population, the percentage of unfavourable outcomes was 48.5% (32/66) for control, 23.3% (14/60) for BPaL, 18.8% (12/64) for BPaLC, and 11.3% (7/62) for BPaLM. There were three recurrences in BPaL, one in BPaLC, and none in BPaLM. Percentage of Grade =3 or SAE were 19.4% (14/72; 16 events), 31.9% (23/72; 32 events) and 21.7% (15/69; 24 events) in BPaLM, BPaLC and BPaL respectively, compared with 58.9% (43/73; 69 events) in the control. Mean change in QTcF at week 24 was 27.0 milliseconds (ms), 40.2 ms, and 23.3 ms in BPaLM, BPaLC, and BPaL respectively; compared with 44.89 ms in the control.
CONCLUSION 24-week all-oral regimens of bedaquiline, pretomanid and tapered-dose linezolid, with and without clofazamine or moxifloxacin are safe and efficacious in the treatment of RR-TB. Trial results show that treatment with BPaLM was more effective and had a better safety profile than the Control. BPaLC and BPaL were also highly effective.
Wharton-Smith A, Horter SCB, Douch E, Gray NSB, James N, et al.
Trials. 2021 December 4; Volume 22; 881 .
BACKGROUND Addressing the global burden of multidrug-resistant tuberculosis (MDR-TB) requires identification of shorter, less toxic treatment regimens. Médecins Sans Frontières (MSF) is currently conducting a phase II/III randomised controlled clinical trial, to find more effective, shorter and tolerable treatments for people with MDR-TB. Recruitment to the trial in Uzbekistan has been slower than expected; we aimed to study patient and health worker experiences of the trial, examining potential factors perceived to impede and facilitate trial recruitment, as well as general perceptions of clinical research in this context.
METHODS We conducted a qualitative study using maximum variation, purposive sampling of participants. We carried out in-depth interviews (IDIs) and focus group discussions (FGDs) guided by semi-structured topic guides. In December 2019 and January 2020, 26 interviews were conducted with patients, Ministry of Health (MoH) and MSF staff and trial health workers, to explore challenges and barriers to patient recruitment as well as perceptions of the trial and research in general. Preliminary findings from the interviews informed three subsequent focus group discussions held with patients, nurses and counsellors. Focus groups adopted a person-centred design, brainstorming potential solutions to problems and barriers. Interviews and FGDs were audio recorded, translated and transcribed verbatim. Thematic analysis, drawing on constant comparison, was used to analyse the data.
RESULTS Health system contexts may compete with new approaches especially when legislative health regulations or policy around treatment is ingrained in staff beliefs, perceptions and practice, which can undermine clinical trial recruitment. Trust plays a significant role in how patients engage with the trial. Decision-making processes are dynamic and associated with relationship to diagnosis, assimilation of information, previous knowledge or experience and influence of peers and close relations.
CONCLUSIONS This qualitative analysis highlights ways in which insights developed together with patients and healthcare workers might inform approaches towards improved recruitment into trials, with the overall objective of delivering evidence for better treatments.More
BMJ Open. 2021 September 6; Volume 11 (Issue 9); e047185.
Nyang'wa BT, Kloprogge F, Moore DAJ, Bustinduy A, Motta I, et al.
BMJ Open. 2021 September 6; Volume 11 (Issue 9); e047185.
INTRODUCTION Drug-resistant tuberculosis (TB) remains a global health threat, with little over 50% of patients successfully treated. Novel regimens like the ones being studied in the TB-PRACTECAL trial are urgently needed. Understanding anti-TB drug exposures could explain the success or failure of these trial regimens. We aim to study the relationship between the patients' exposure to anti-TB drugs in TB-PRACTECAL investigational regimens and their treatment outcomes.
METHODS AND ANALYSIS Adults with multidrug-resistant TB randomised to investigational regimens in TB-PRACTECAL will be recruited to a nested pharmacokinetic-pharmacodynamic (PKPD) study. Venous blood samples will be collected at 0, 2 and 23 hours postdose on day 1 and 0, 6.5 and 23 hours postdose during week 8 to quantify drug concentrations in plasma. Trough samples will be collected during week 12, 16, 20 and 24 visits. Opportunistic samples will be collected during weeks 32 and 72. Drug concentrations will be quantified using liquid chromatography-tandem mass spectrometry. Sputum samples will be collected at baseline, monthly to week 24 and then every 2 months to week 108 for MICs and bacillary load quantification. Full blood count, urea and electrolytes, liver function tests, lipase, ECGs and ophthalmology examinations will be conducted at least monthly during treatment.PK and PKPD models will be developed for each drug with nonlinear mixed effects methods. Optimal dosing will be investigated using Monte-Carlo simulations.
ETHICS AND DISSEMINATION The study has been approved by the Médecins sans Frontières (MSF) Ethics Review Board, the LSHTM Ethics Committee, the Belarus RSPCPT ethics committee and PharmaEthics and the University of Witwatersrand Human Research ethics committee in South Africa. Written informed consent will be obtained from all participants. The study results will be shared with public health authorities, presented at scientific conferences and published in a peer-reviewed journal.More
BMJ Open. 2021 September 6; Volume 11 (Issue 9); e043954.
Stringer B, Lowton K, James N, Nyang'wa BT
BMJ Open. 2021 September 6; Volume 11 (Issue 9); e043954.
INTRODUCTION People living with multidrug-resistant tuberculosis currently have few options for effective treatment and cure. Regimens that are available are toxic, may involve injections and take up to 2?years to complete treatment, with success rates as low as 50%. The TB-PRACTECAL trial is evaluating shorter, more tolerable regimens of oral drugs; we detail the substudy within this trial, PRACTECAL-PRO, which aims to evaluate patient experiences and perspectives on treatment, to understand outcomes more fully.
METHODS AND ANALYSIS We are conducting a mixed-methods evaluation within both investigational and standard of care arms within the TB-PRACTECAL trial, using sequential quality of life (QoL) surveys and in-depth interviews. Data collection involves the Short Form 12 (SF-12) and St George’s Respiratory Questionnaire (SGRQ), collected at up to four fixed timepoints, from baseline, to up to 12 months later. Healthy volunteers will be surveyed to establish locally relevant controls. We will also purposively sample participants for qualitative data collection and analysis, to provide rich explanation of QoL scores. The study will be implemented in all six TB-PRACTECAL study sites in Uzbekistan, South Africa and Belarus. QoL surveys will be scored and analysed according to SF-12 and SGRQ developers’ manuals. Differences between scores at baseline and later timepoints will be evaluated as well as graphical exploration of group score trajectories of investigational and standard of care arms.
ETHICS AND DISSEMINATION Ethics approval was obtained from the Médecins Sans Frontières Ethics Review Board. Local ethics approval has been obtained in Uzbekistan, Belarus and South Africa. Results of the substudy will be shared with local health authorities, the WHO and submitted for publication in a peer-reviewed journal.
Trial registration number NCT03942354; Pre-results.More
Nyang'wa BT, LaHood AN, Mitnick CD, Guglielmetti L
Trials. 2021 May 29; Volume 22 (Issue 1); 371.
When 2020 opened, approximately 11 million new tuberculosis (TB) cases and nearly 1.5 million TB-related deaths were predicted during the year. And, the gap between required and available research and development resources for TB was estimated at more than 1 billion USD. COVID-19, the global pandemic of disease caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has surely widened that gap by worsening the TB pandemic. Worryingly, the economic devastation wrought by COVID-19 portends further dramatic reductions in funds for other health research, including for multidrug-resistant tuberculosis (MDR-TB). Such constraints will prevent the use of extant TB research infrastructure to support cross-disease benefits in the struggle against COVID-19 and future pandemics.More
BMJ Open. 2020 October 10; Volume 10 (Issue 10); e036599.
Sweeney S, Gomez G, Kitson N, Sinha A, Yatskevich N, et al.
BMJ Open. 2020 October 10; Volume 10 (Issue 10); e036599.
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.More