Journal Article > Short ReportFull Text
Clin Infect Dis. 2019 November 2; Volume 71 (Issue 2); 415-418.; DOI:10.1093/cid/ciz1084
Seung KJ, Khan PY, Franke MF, Ahmed SM, Aiylchiev S, et al.
Clin Infect Dis. 2019 November 2; Volume 71 (Issue 2); 415-418.; DOI:10.1093/cid/ciz1084
Delamanid should be effective against highly resistant strains of Mycobacterium tuberculosis, but uptake has been slow globally. In the endTB (expand new drug markets for TB) Observational Study, which enrolled a large, heterogeneous cohorts of patients receiving delamanid as part of a multidrug regimen, 80% of participants experienced sputum culture conversion within 6 months.
Protocol
BMJ Open. 2017 February 1; Volume 7 (Issue 2); e014067.; DOI:10.1136/bmjopen-2016-014067
Smith SL, Misago CN, Osrow RA, Franke MF, Iyamuremye JD, et al.
BMJ Open. 2017 February 1; Volume 7 (Issue 2); e014067.; DOI:10.1136/bmjopen-2016-014067
Integrating mental healthcare into primary care can reduce the global burden of mental disorders. Yet data on the effective implementation of real-world task-shared mental health programmes are limited. In 2012, the Rwandan Ministry of Health and the international healthcare organisation Partners in Health collaboratively adapted the Mentoring and Enhanced Supervision at Health Centers (MESH) programme, a successful programme of supported supervision based on task-sharing for HIV/AIDS care, to include care of neuropsychiatric disorders within primary care settings (MESH Mental Health). We propose 1 of the first studies in a rural low-income country to assess the implementation and clinical outcomes of a programme integrating neuropsychiatric care into a public primary care system.
METHODS AND ANALYSIS
A mixed-methods evaluation will be conducted. First, we will conduct a quantitative outcomes evaluation using a pretest and post-test design at 4 purposively selected MESH MH participating health centres. At least 112 consecutive adults with schizophrenia, bipolar disorder, depression or epilepsy will be enrolled. Primary outcomes are symptoms and functioning measured at baseline, 8 weeks and 6 months using clinician-administered scales: the General Health Questionnaire and the brief WHO Disability Assessment Scale. We hypothesise that service users will experience at least a 25% improvement in symptoms and functioning from baseline after MESH MH programme participation. To understand any outcome improvements under the intervention, we will evaluate programme processes using (1) quantitative analyses of routine service utilisation data and supervision checklist data and (2) qualitative semistructured interviews with primary care nurses, service users and family members.
ETHICS AND DISSEMINATION
This evaluation was approved by the Rwanda National Ethics Committee (Protocol #736/RNEC/2016) and deemed exempt by the Harvard University Institutional Review Board. Results will be submitted for peer-reviewed journal publication, presented at conferences and disseminated to communities served by the programme.
METHODS AND ANALYSIS
A mixed-methods evaluation will be conducted. First, we will conduct a quantitative outcomes evaluation using a pretest and post-test design at 4 purposively selected MESH MH participating health centres. At least 112 consecutive adults with schizophrenia, bipolar disorder, depression or epilepsy will be enrolled. Primary outcomes are symptoms and functioning measured at baseline, 8 weeks and 6 months using clinician-administered scales: the General Health Questionnaire and the brief WHO Disability Assessment Scale. We hypothesise that service users will experience at least a 25% improvement in symptoms and functioning from baseline after MESH MH programme participation. To understand any outcome improvements under the intervention, we will evaluate programme processes using (1) quantitative analyses of routine service utilisation data and supervision checklist data and (2) qualitative semistructured interviews with primary care nurses, service users and family members.
ETHICS AND DISSEMINATION
This evaluation was approved by the Rwanda National Ethics Committee (Protocol #736/RNEC/2016) and deemed exempt by the Harvard University Institutional Review Board. Results will be submitted for peer-reviewed journal publication, presented at conferences and disseminated to communities served by the programme.
Journal Article > ResearchFull Text
Clin Infect Dis. 2024 January 25; Volume 78 (Issue 1); 164-171.; DOI:10.1093/cid/ciad589
Sauer SM, Mitnick CD, Khan UT, Hewison CCH, Bastard M, et al.
Clin Infect Dis. 2024 January 25; Volume 78 (Issue 1); 164-171.; DOI:10.1093/cid/ciad589
BACKGROUND
Quantification of recurrence risk following successful treatment is crucial to evaluating regimens for multidrug- or rifampicin-resistant (MDR/RR) tuberculosis (TB). However, such analyses are complicated when some patients die or become lost during post-treatment-follow-up.
METHODS
We analyzed data on 1,991 patients who successfully completed a longer MDR/RR-TB regimen containing bedaquiline and/or delamanid between 2015 and 2018 in 16 countries. Using five approaches for handling post-treatment deaths, we estimated the six-month post-treatment TB recurrence risk overall, and by HIV status. We used inverse-probability-weighting to account for patients with missing follow-up and investigated the impact of potential bias from excluding these patients without applying inverse-probability weights.
RESULTS
The estimated TB recurrence risk was 7.4 per 1000 (95% confidence interval (CI): 3.5,12.9) when deaths were handled as non-recurrences, and 7.6 per 1000 (95% CI: 3.6,13.1) when deaths were censored and inverse-probability weights were applied to account for the excluded deaths. The estimated risk of composite recurrence outcomes were 25.5 (95% CI: 15.4,38.1), 11.7 (95% CI: 6.5,18.3), and 8.6 (95% CI: 4.2,14.6) per 1000 for recurrence or 1) any death, 2) death with unknown or TB-related cause, 3) TB-related death, respectively. Corresponding relative risks for HIV status varied in direction and magnitude. Exclusion of patients with missing follow-up without inverse-probability-weighting had a small impact on estimates.
CONCLUSIONS
The estimated six-month TB recurrence risk was low, and the association with HIV status was inconclusive due to few recurrence events. Estimation of post-treatment recurrence will be enhanced by explicit assumptions about deaths and appropriate adjustment for missing follow-up data.
Quantification of recurrence risk following successful treatment is crucial to evaluating regimens for multidrug- or rifampicin-resistant (MDR/RR) tuberculosis (TB). However, such analyses are complicated when some patients die or become lost during post-treatment-follow-up.
METHODS
We analyzed data on 1,991 patients who successfully completed a longer MDR/RR-TB regimen containing bedaquiline and/or delamanid between 2015 and 2018 in 16 countries. Using five approaches for handling post-treatment deaths, we estimated the six-month post-treatment TB recurrence risk overall, and by HIV status. We used inverse-probability-weighting to account for patients with missing follow-up and investigated the impact of potential bias from excluding these patients without applying inverse-probability weights.
RESULTS
The estimated TB recurrence risk was 7.4 per 1000 (95% confidence interval (CI): 3.5,12.9) when deaths were handled as non-recurrences, and 7.6 per 1000 (95% CI: 3.6,13.1) when deaths were censored and inverse-probability weights were applied to account for the excluded deaths. The estimated risk of composite recurrence outcomes were 25.5 (95% CI: 15.4,38.1), 11.7 (95% CI: 6.5,18.3), and 8.6 (95% CI: 4.2,14.6) per 1000 for recurrence or 1) any death, 2) death with unknown or TB-related cause, 3) TB-related death, respectively. Corresponding relative risks for HIV status varied in direction and magnitude. Exclusion of patients with missing follow-up without inverse-probability-weighting had a small impact on estimates.
CONCLUSIONS
The estimated six-month TB recurrence risk was low, and the association with HIV status was inconclusive due to few recurrence events. Estimation of post-treatment recurrence will be enhanced by explicit assumptions about deaths and appropriate adjustment for missing follow-up data.
Journal Article > CommentaryFull Text
Int J Tuberc Lung Dis. 2020 October 1; Volume 24 (Issue 10); 1081-1086.; DOI:10.5588/ijtld.20.0141
Seung KJ, Khan UT, Varaine FFV, Ahmed SM, Bastard M, et al.
Int J Tuberc Lung Dis. 2020 October 1; Volume 24 (Issue 10); 1081-1086.; DOI:10.5588/ijtld.20.0141
In 2015, the initiative Expand New Drug Markets for TB (endTB) began, with the objective of reducing barriers to access to the new and repurposed TB drugs. Here we describe the major implementation challenges encountered in 17 endTB countries. We provide insights on how national TB programmes and other stakeholders can scale-up the programmatic use of new and repurposed TB drugs, while building scientific evidence about their safety and efficacy. For any new drug or diagnostic, multiple market barriers can slow the pace of scale-up. During 2015–2019, endTB was successful in increasing the number of patients receiving new and repurposed TB drugs in 17 countries. The endTB experience has many lessons, which are relevant to country level introduction of new TB drugs, as well as non-TB drugs and diagnostics. For example: the importation of TB drugs is possible even in the absence of registration; emphasis on good clinical monitoring is more important than pharmacovigilance reporting; national guidelines and expert committees can both facilitate and hinder innovative practice; clinicians use new and repurposed TB drugs when they are available; data collection to generate scientific evidence requires financial and human resources; pilot projects can drive national scale-up.
Journal Article > ResearchFull Text
medRxiv. 2024 January 20; DOI:10.1101/2024.01.18.24301453
Zeng C, Hernán MA, Trevisi L, Sauer S, Mitnick CD, et al.
medRxiv. 2024 January 20; DOI:10.1101/2024.01.18.24301453
RATIONALE
Treatment outcomes may be compromised among patients with multidrug- or rifampicin-resistant tuberculosis with additional fluoroquinolone resistance. Evidence is needed to inform optimal treatment for these patients.
OBJECTIVES
We compared the effectiveness of longer individualized regimens comprised of bedaquiline for 5 to 8 months, linezolid, and clofazimine to those reinforced with at least 1 third-tier drug and/or longer duration of bedaquiline.
METHODS
We emulated a target trial to compare the effectiveness of initiating and remaining on the core regimen to one of five regimens reinforced with (1) bedaquiline for ≥9 months, (2) bedaquiline for ≥9 months and delamanid, (3) imipenem, (4) a second-line injectable, or (5) delamanid and imipenem. We included patients in whom a fluoroquinolone was unlikely to be effective based on drug susceptibility testing and/or prior exposure. Our analysis consisted of cloning, censoring, and inverse-probability weighting to estimate the probability of successful treatment.
MEASUREMENTS AND MAIN RESULTS
Adjusted probabilities of successful treatment were high across regimens, ranging from 0.75 (95%CI:0.61, 0.89) to 0.84 (95%CI:0.76, 0.91). We found no substantial evidence that any of the reinforced regimens improved effectiveness of the core regimen, with ratios of treatment success ranging from 1.01 for regimens reinforced with bedaquiline ≥9 months (95%CI:0.79, 1.28) and bedaquiline ≥9 months plus delamanid (95%CI:0.81, 1.31) to 1.11 for regimens reinforced by a second-line injectable (95%CI:0.92, 1.39) and delamanid and imipenem (95%CI:0.90, 1.41).
CONCLUSIONS
High treatment success underscores the effectiveness of regimens comprised of bedaquiline, linezolid, and clofazimine, highlighting the need for expanded access to these drugs.
Journal Article > ResearchFull Text
Int J Tuberc Lung Dis. 2023 January 1; Volume 27 (Issue 1); 34-40.; DOI:10.5588/ijtld.22.0324
Zeng C, Mitnick CD, Hewison CCH, Bastard M, Khan PY, et al.
Int J Tuberc Lung Dis. 2023 January 1; Volume 27 (Issue 1); 34-40.; DOI:10.5588/ijtld.22.0324
BACKGROUND
The WHO provides standardized outcome definitions for rifampicin-resistant (RR) and multidrug-resistant (MDR) TB. However, operationalizing these definitions can be challenging in some clinical settings, and incorrect classification may generate bias in reporting and research. Outcomes calculated by algorithms can increase standardization and be adapted to suit the research question. We evaluated concordance between clinician-assigned treatment outcomes and outcomes calculated based on one of two standardized algorithms, one which identified failure at its earliest possible recurrence (i.e., failure-dominant algorithm), and one which calculated the outcome based on culture results at the end of treatment, regardless of early occurrence of failure (i.e., success-dominant algorithm).
METHODS
Among 2,525 patients enrolled in the multi-country endTB observational study, we calculated the frequencies of concordance using cross-tabulations of clinician-assigned and algorithm-assigned outcomes. We summarized the common discrepancies.
RESULTS
Treatment success calculated by algorithms had high concordance with treatment success assigned by clinicians (95.8 and 97.7% for failure-dominant and success-dominant algorithms, respectively). The frequency and pattern of the most common discrepancies varied by country.
CONCLUSION
High concordance was found between clinician-assigned and algorithm-assigned outcomes. Heterogeneity in discrepancies across settings suggests that using algorithms to calculate outcomes may minimize bias.
The WHO provides standardized outcome definitions for rifampicin-resistant (RR) and multidrug-resistant (MDR) TB. However, operationalizing these definitions can be challenging in some clinical settings, and incorrect classification may generate bias in reporting and research. Outcomes calculated by algorithms can increase standardization and be adapted to suit the research question. We evaluated concordance between clinician-assigned treatment outcomes and outcomes calculated based on one of two standardized algorithms, one which identified failure at its earliest possible recurrence (i.e., failure-dominant algorithm), and one which calculated the outcome based on culture results at the end of treatment, regardless of early occurrence of failure (i.e., success-dominant algorithm).
METHODS
Among 2,525 patients enrolled in the multi-country endTB observational study, we calculated the frequencies of concordance using cross-tabulations of clinician-assigned and algorithm-assigned outcomes. We summarized the common discrepancies.
RESULTS
Treatment success calculated by algorithms had high concordance with treatment success assigned by clinicians (95.8 and 97.7% for failure-dominant and success-dominant algorithms, respectively). The frequency and pattern of the most common discrepancies varied by country.
CONCLUSION
High concordance was found between clinician-assigned and algorithm-assigned outcomes. Heterogeneity in discrepancies across settings suggests that using algorithms to calculate outcomes may minimize bias.
Protocol > Research Study
BMC Infect Dis. 2019 August 20; Volume 19 (Issue 1); 733.; DOI:10.1186/s12879-019-4378-4
Khan UT, Huerga H, Khan AS, Mitnick CD, Hewison CCH, et al.
BMC Infect Dis. 2019 August 20; Volume 19 (Issue 1); 733.; DOI:10.1186/s12879-019-4378-4
BACKGROUND
At a time when programs were struggling to design effective regimens for the treatment of multidrug-resistant tuberculosis (MDR-TB), the marketing authorization of bedaquiline and delamanid was a critical development in the MDR-TB treatment landscape. However, despite their availability for routine programmatic use, the uptake of these drugs has remained slow; concerns included a lack of evidence on safety and efficacy and the need to protect the new drugs from the development of acquired resistance. As part of the endTB Project, we aimed to address these barriers by generating evidence on safety and efficacy of bedaquiline or delamanid based MDR-TB regimens.
METHODS
This is a protocol for a multi-center prospective cohort study to enroll 2600 patients from April 2015 through September 2018 in 17 countries. The protocol describes inclusion of patients started on treatment with bedaquiline- or delamanid- containing regimens under routine care, who consented to participate in the endTB observational study. Patient follow-up was according to routine monitoring schedules recommended for patients receiving bedaquiline or delamanid as implemented at each endTB site. Therefore, no additional tests were performed as a part of the study. Data were to be collected in a customized, open-source electronic medical record (EMR) system developed as a part of the endTB Project across all 17 countries.
DISCUSSION
The endTB observational study will generate evidence on safety and efficacy of bedaquiline- and delamanid-containing regimens in a large, extremely heterogeneous group of MDR-TB patients, from 17 epidemiologically diverse countries. The systematic, prospective data collection of repeated effectiveness and safety measures, and analyses performed on these data, will improve the quality of evidence available to inform MDR-TB treatment and policy decisions. Further, the resources available to countries through implementation of the endTB project will have permitted countries to: gain experience with the use of these drugs in MDR-TB regimens, improve local capacity to record and report adverse events (pharmacovigilance), and enhance significantly the body of data available for safety evaluation of these drugs and other novel treatments.
At a time when programs were struggling to design effective regimens for the treatment of multidrug-resistant tuberculosis (MDR-TB), the marketing authorization of bedaquiline and delamanid was a critical development in the MDR-TB treatment landscape. However, despite their availability for routine programmatic use, the uptake of these drugs has remained slow; concerns included a lack of evidence on safety and efficacy and the need to protect the new drugs from the development of acquired resistance. As part of the endTB Project, we aimed to address these barriers by generating evidence on safety and efficacy of bedaquiline or delamanid based MDR-TB regimens.
METHODS
This is a protocol for a multi-center prospective cohort study to enroll 2600 patients from April 2015 through September 2018 in 17 countries. The protocol describes inclusion of patients started on treatment with bedaquiline- or delamanid- containing regimens under routine care, who consented to participate in the endTB observational study. Patient follow-up was according to routine monitoring schedules recommended for patients receiving bedaquiline or delamanid as implemented at each endTB site. Therefore, no additional tests were performed as a part of the study. Data were to be collected in a customized, open-source electronic medical record (EMR) system developed as a part of the endTB Project across all 17 countries.
DISCUSSION
The endTB observational study will generate evidence on safety and efficacy of bedaquiline- and delamanid-containing regimens in a large, extremely heterogeneous group of MDR-TB patients, from 17 epidemiologically diverse countries. The systematic, prospective data collection of repeated effectiveness and safety measures, and analyses performed on these data, will improve the quality of evidence available to inform MDR-TB treatment and policy decisions. Further, the resources available to countries through implementation of the endTB project will have permitted countries to: gain experience with the use of these drugs in MDR-TB regimens, improve local capacity to record and report adverse events (pharmacovigilance), and enhance significantly the body of data available for safety evaluation of these drugs and other novel treatments.
Journal Article > LetterFull Text
J Hepatol. 2020 May 1; Volume 72 (Issue 5); 1028-1029.; DOI:10.1016/j.jhep.2019.10.018
Seung KJ, Franke MF, Hewison CCH, Huerga H, Khan UT, et al.
J Hepatol. 2020 May 1; Volume 72 (Issue 5); 1028-1029.; DOI:10.1016/j.jhep.2019.10.018
Journal Article > ResearchFull Text
Clin Infect Dis. 2022 October 15; Volume 75 (Issue 8); 1307-1314.; DOI:10.1093/cid/ciac176
Huerga H, Khan UT, Bastard M, Mitnick CD, Lachenal N, et al.
Clin Infect Dis. 2022 October 15; Volume 75 (Issue 8); 1307-1314.; DOI:10.1093/cid/ciac176
BACKGROUND
Concomitant use of bedaquiline (Bdq) and delamanid (Dlm) for multi-drug/rifampicin resistant tuberculosis (MDR/RR-TB) has raised concerns about a potentially poor risk-benefit ratio. Yet, this combination is an important alternative for patients infected with strains of TB with complex drug resistance profiles or who cannot tolerate other therapies. We assessed safety and treatment outcomes of MDR/RR-TB patients receiving concomitant Bdq and Dlm, along with other second-line anti-TB drugs.
METHODS
We conducted a multi-centric, prospective observational cohort study across 14 countries among patients receiving concomitant Bdq-Dlm treatment. Patients were recruited between April 2015 and September 2018 and were followed until the end of treatment. All serious adverse events and adverse events of special interest (AESI), leading to a treatment change, or judged significant by a clinician, were systematically monitored and documented.
RESULTS
Overall, 472 patients received Bdq and Dlm concomitantly. A large majority also received linezolid (89.6%) and clofazimine (84.5%). Nearly all (90.3%) had extensive disease; most (74.2%) had resistance to fluoroquinolones. The most common AESI were peripheral neuropathy (134, 28.4%) and electrolyte depletion (94, 19.9%). Acute kidney injury and myelosuppression were seen in 40 (8.5%) and 24 (5.1%) of patients, respectively. QT prolongation occurred in 7 (1.5%). Overall, 78.0% (358/458) had successful treatment outcomes, 8.9% died and 7.2% experienced treatment failure.
CONCLUSIONS
Concomitant use of Bdq and Dlm, along with linezolid and clofazimine, is safe and effective for MDR/RR-TB patients with extensive disease. Using these drugs concomitantly is a good therapeutic option for patients with resistance to many anti-TB drugs.
Concomitant use of bedaquiline (Bdq) and delamanid (Dlm) for multi-drug/rifampicin resistant tuberculosis (MDR/RR-TB) has raised concerns about a potentially poor risk-benefit ratio. Yet, this combination is an important alternative for patients infected with strains of TB with complex drug resistance profiles or who cannot tolerate other therapies. We assessed safety and treatment outcomes of MDR/RR-TB patients receiving concomitant Bdq and Dlm, along with other second-line anti-TB drugs.
METHODS
We conducted a multi-centric, prospective observational cohort study across 14 countries among patients receiving concomitant Bdq-Dlm treatment. Patients were recruited between April 2015 and September 2018 and were followed until the end of treatment. All serious adverse events and adverse events of special interest (AESI), leading to a treatment change, or judged significant by a clinician, were systematically monitored and documented.
RESULTS
Overall, 472 patients received Bdq and Dlm concomitantly. A large majority also received linezolid (89.6%) and clofazimine (84.5%). Nearly all (90.3%) had extensive disease; most (74.2%) had resistance to fluoroquinolones. The most common AESI were peripheral neuropathy (134, 28.4%) and electrolyte depletion (94, 19.9%). Acute kidney injury and myelosuppression were seen in 40 (8.5%) and 24 (5.1%) of patients, respectively. QT prolongation occurred in 7 (1.5%). Overall, 78.0% (358/458) had successful treatment outcomes, 8.9% died and 7.2% experienced treatment failure.
CONCLUSIONS
Concomitant use of Bdq and Dlm, along with linezolid and clofazimine, is safe and effective for MDR/RR-TB patients with extensive disease. Using these drugs concomitantly is a good therapeutic option for patients with resistance to many anti-TB drugs.
Journal Article > ResearchFull Text
Effectiveness of bedaquiline use beyond six months in patients with multidrug-resistant tuberculosis
Am J Respir Crit Care Med. 2023 June 1; Volume 207 (Issue 11); 1525-1532.; DOI:10.1164/rccm.202211-2125OC
Trevisi L, Hernán MA, Mitnick CD, Khan UT, Seung KJ, et al.
Am J Respir Crit Care Med. 2023 June 1; Volume 207 (Issue 11); 1525-1532.; DOI:10.1164/rccm.202211-2125OC
RATIONALE
Current recommendations for the treatment of rifampin- and multidrug-resistant tuberculosis include bedaquiline used for six months or longer. Evidence is needed to inform the optimal duration of bedaquiline.
OBJECTIVES
We emulated a target trial to estimate the effect of three bedaquiline duration treatment strategies (6 months, 7-11 months, ≥ 12 months) on the probability of successful treatment among patients receiving a longer individualized regimen for multidrug-resistant tuberculosis.
METHODS
To estimate the probability of successful treatment, we implemented a three-step approach comprising cloning, censoring, and inverse-probability weighting.
MAIN RESULTS
The 1,468 eligible individuals received a median of four (IQR: 4-5) likely effective drugs. In 87.1% and 77.7%, this included linezolid and clofazimine, respectively. The adjusted probability of successful treatment (95% CI) was 0.85 (0.81, 0.88) for 6 months of BDQ, 0.77 (0.73, 0.81) for 7-11 months, and 0.86 (0.83, 0.88) for > 12 months. Compared with 6 months of bedaquiline, the ratio of treatment success (95% CI) was 0.91 (0.85, 0.96) for 7-11 months and 1.01 (0.96, 1.06) for > 12 months. Analyses that did not account for immortal time bias found a higher probability of successful treatment with > 12 months: ratio 1.09 (1.05, 1.14).
CONCLUSIONS
Bedaquiline use beyond six months did not increase the probability of successful treatment among patients receiving longer regimens that commonly included new and repurposed drugs. When not properly accounted for, immortal person-time can bias estimate of effects of treatment duration. Future analyses should explore the effect of duration of bedaquiline and other drugs in subgroups with advanced disease and/or receiving less potent regimens.
Current recommendations for the treatment of rifampin- and multidrug-resistant tuberculosis include bedaquiline used for six months or longer. Evidence is needed to inform the optimal duration of bedaquiline.
OBJECTIVES
We emulated a target trial to estimate the effect of three bedaquiline duration treatment strategies (6 months, 7-11 months, ≥ 12 months) on the probability of successful treatment among patients receiving a longer individualized regimen for multidrug-resistant tuberculosis.
METHODS
To estimate the probability of successful treatment, we implemented a three-step approach comprising cloning, censoring, and inverse-probability weighting.
MAIN RESULTS
The 1,468 eligible individuals received a median of four (IQR: 4-5) likely effective drugs. In 87.1% and 77.7%, this included linezolid and clofazimine, respectively. The adjusted probability of successful treatment (95% CI) was 0.85 (0.81, 0.88) for 6 months of BDQ, 0.77 (0.73, 0.81) for 7-11 months, and 0.86 (0.83, 0.88) for > 12 months. Compared with 6 months of bedaquiline, the ratio of treatment success (95% CI) was 0.91 (0.85, 0.96) for 7-11 months and 1.01 (0.96, 1.06) for > 12 months. Analyses that did not account for immortal time bias found a higher probability of successful treatment with > 12 months: ratio 1.09 (1.05, 1.14).
CONCLUSIONS
Bedaquiline use beyond six months did not increase the probability of successful treatment among patients receiving longer regimens that commonly included new and repurposed drugs. When not properly accounted for, immortal person-time can bias estimate of effects of treatment duration. Future analyses should explore the effect of duration of bedaquiline and other drugs in subgroups with advanced disease and/or receiving less potent regimens.