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53 result(s)
Journal Article > ResearchFull Text

Estimating post-treatment recurrence after multidrug-resistant tuberculosis treatment among patients with and without HIV: the impact of assumptions about death and missing follow-up

Clin Infect Dis. 25 January 2024; 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. 25 January 2024; 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.
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Journal Article > Short ReportFull Text

Pregnancy and birth outcomes in patients with multidrug-resistant tuberculosis treated with regimens that include new and repurposed drugs

Clin Infect Dis. 25 January 2024; Volume 78 (Issue 1); 144-148.; DOI:10.1093/cid/ciad445
Lotia Farrukh I, Lachenal N, Adenov MM, Ahmed SM, Algozhin Y,  et al.
Clin Infect Dis. 25 January 2024; Volume 78 (Issue 1); 144-148.; DOI:10.1093/cid/ciad445
Among 43 pregnant women receiving multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) treatment with bedaquiline and/or delamanid, 98% had favorable treatment outcomes. Of 31 continued pregnancies, 81% had live births with no reported malformations, and 68% of neonates had normal birth weights. Effective MDR/RR-TB treatment during pregnancy can improve maternal outcomes without harming neonates.More
Journal Article > ResearchFull Text

Target product profiles: tests for tuberculosis treatment monitoring and optimization

Bull World Health Organ. 1 November 2023; Volume 101 (Issue 11); 730-737.; DOI:10.2471/BLT.23.290901
Gupta-Wright A, den Boon S, MacLean E, Cirillo DM, Cobelens F,  et al.
Bull World Health Organ. 1 November 2023; Volume 101 (Issue 11); 730-737.; DOI:10.2471/BLT.23.290901
English
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The World Health Organization has developed target product profiles containing minimum and optimum targets for key characteristics for tests for tuberculosis treatment monitoring and optimization. Tuberculosis treatment optimization refers to initiating or switching to an effective tuberculosis treatment regimen that results in a high likelihood of a good treatment outcome. The target product profiles also cover tests of cure conducted at the end of treatment. The development of the target product profiles was informed by a stakeholder survey, a cost-effectiveness analysis and a patient-care pathway analysis. Additional feedback from stakeholders was obtained by means of a Delphi-like process, a technical consultation and a call for public comment on a draft document. A scientific development group agreed on the final targets in a consensus meeting. For characteristics rated of highest importance, the document lists: (i) high diagnostic accuracy (sensitivity and specificity); (ii) time to result of optimally ≤ 2 hours and no more than 1 day; (iii) required sample type to be minimally invasive, easily obtainable, such as urine, breath, or capillary blood, or a respiratory sample that goes beyond sputum; (iv) ideally the test could be placed at a peripheral-level health facility without a laboratory; and (v) the test should be affordable to low- and middle-income countries, and allow wide and equitable access and scale-up. Use of these target product profiles should facilitate the development of new tuberculosis treatment monitoring and optimization tests that are accurate and accessible for all people being treated for tuberculosis.More
Journal Article > CommentaryFull Text

Reversing the neglect of children and adolescents affected by tuberculosis

Lancet Child Adolesc Health. 11 September 2023; Volume 7 (Issue 10); 675-677.; DOI:10.1016/S2352-4642(23)00217-1
Deborggraeve S, Casenghi M, Hewison CCH, Ditekemena J, Ditiu L,  et al.
Lancet Child Adolesc Health. 11 September 2023; Volume 7 (Issue 10); 675-677.; DOI:10.1016/S2352-4642(23)00217-1
Journal Article > ResearchFull Text

Effectiveness of bedaquiline use beyond six months in patients with multidrug-resistant tuberculosis

Am J Respir Crit Care Med. 1 June 2023; 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. 1 June 2023; 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.
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Journal Article > ResearchFull Text

Outcomes of WHO-conforming, longer, all-oral multidrug-resistant TB regimens and analysis implications

Int J Tuberc Lung Dis. 1 June 2023; Volume 27 (Issue 6); 451-457.; DOI:10.5588/ijtld.22.0613
Rich ML, Khan UT, Zeng C, LaHood AN, Franke MF,  et al.
Int J Tuberc Lung Dis. 1 June 2023; Volume 27 (Issue 6); 451-457.; DOI:10.5588/ijtld.22.0613
English
Français
BACKGROUND
Evidence of the effectiveness of the WHO-recommended design of longer individualized regimens for multidrug- or rifampicin-resistant TB (MDR/RR-TB) is limited.

OBJECTIVES
To report end-of-treatment outcomes for MDR/RR-TB patients from a 2015–2018 multi-country cohort that received a regimen consistent with current 2022 WHO updated recommendations and describe the complexities of comparing regimens.

METHODS
We analyzed a subset of participants from the endTB Observational Study who initiated a longer MDR/RR-TB regimen that was consistent with subsequent 2022 WHO guidance on regimen design for longer treatments. We excluded individuals who received an injectable agent or who received fewer than four likely effective drugs.

RESULTS
Of the 759 participants analyzed, 607 (80.0%, 95% CI 77.0–82.7) experienced successful end-of-treatment outcomes. The frequency of success was high across groups, whether stratified on number of Group A drugs or fluoroquinolone resistance, and ranged from 72.1% to 90.0%. Regimens were highly variable regarding composition and the duration of individual drugs.

CONCLUSIONS
Longer, all-oral, individualized regimens that were consistent with 2022 WHO guidance on regimen design had high frequencies of treatment success. Heterogeneous regimen compositions and drug durations precluded meaningful comparisons. Future research should examine which combinations of drugs maximize safety/tolerability and effectiveness.
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Journal Article > Research

Comparative effectiveness of adding delamanid to a multidrug-resistant tuberculosis regimen comprised of three drugs likely to be effective

PLOS Glob Public Health. 28 April 2023; Volume 3 (Issue 4); e0000818.; DOI:10.1371/journal.pgph.0000818
Rodriguez CA, Lodi S, Horsburgh CR, Mitnick CD, Bastard M,  et al.
PLOS Glob Public Health. 28 April 2023; Volume 3 (Issue 4); e0000818.; DOI:10.1371/journal.pgph.0000818
Clarity about the role of delamanid in longer regimens for multidrug-resistant TB is needed after discordant Phase IIb and Phase III randomized controlled trial results. The Phase IIb trial found that the addition of delamanid to a background regimen hastened culture conversion; the results of the Phase III trial were equivocal. We evaluated the effect of adding delamanid for 24 weeks to three-drug MDR/RR-TB regimens on two- and six-month culture conversion in the endTB observational study. We used pooled logistic regression to estimate the observational analogue of the intention-to-treat effect (aITT) adjusting for baseline confounders and to estimate the observational analogue of the per-protocol effect (aPP) using inverse probability of censoring weighting to control for time-varying confounding. At treatment initiation, 362 patients received three likely effective drugs (delamanid-free) or three likely effective drugs plus delamanid (delamanid-containing). Over 80% of patients received two to three Group A drugs (bedaquiline, linezolid, moxifloxacin/levofloxacin) in their regimen. We found no evidence the addition of delamanid to a three-drug regimen increased two-month (aITT relative risk: 0.90 (95% CI: 0.73–1.11), aPP relative risk: 0.89 (95% CI: 0.66–1.21)) or six-month culture conversion (aITT relative risk: 0.94 (95% CI: 0.84, 1.02), aPP relative risk: 0.93 (95% CI: 0.83, 1.04)). In regimens containing combinations of three likely effective, highly active anti-TB drugs the addition of delamanid had no discernible effect on culture conversion at two or six months. As the standard of care for MDR/RR-TB treatment becomes more potent, it may become increasingly difficult to detect the benefit of adding a single agent to standard of care MDR/RR-TB regimens. Novel approaches like those implemented may help account for background regimens and establish effectiveness of new chemical entities.More
Journal Article > LetterFull Text

Lots of considerations when evaluating the FujiLAM assay – Author's reply

Lancet Global Health. 1 April 2023; Volume 11 (Issue 4); e502.; DOI:10.1016/S2214-109X(23)00115-8
Huerga H, Gupta-Wright A, Muyindike WR, Hewison CCH, Casenghi M,  et al.
Lancet Global Health. 1 April 2023; Volume 11 (Issue 4); e502.; DOI:10.1016/S2214-109X(23)00115-8
Journal Article > ResearchFull Text

Concordance of three approaches for operationalizing outcome definitions for multidrug-resistant TB

Int J Tuberc Lung Dis. 1 January 2023; 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. 1 January 2023; 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.
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Journal Article > ResearchFull Text

Novel FujiLAM assay to detect tuberculosis in HIV-positive ambulatory patients in four African countries: a diagnostic accuracy study

Lancet Global Health. 1 January 2023; Volume 11 (Issue 1); e126-e135.; DOI:10.1016/S2214-109X(22)00463-6
Huerga H, Bastard M, Lubega AV, Akinyi M, Antabak NT,  et al.
Lancet Global Health. 1 January 2023; Volume 11 (Issue 1); e126-e135.; DOI:10.1016/S2214-109X(22)00463-6
BACKGROUND
Development of rapid biomarker-based tests that can diagnose tuberculosis using non-sputum samples is a priority for tuberculosis control. We aimed to compare the diagnostic accuracy of the novel Fujifilm SILVAMP TB LAM (FujiLAM) assay with the WHO-recommended Alere Determine TB-LAM Ag test (AlereLAM) using urine samples from HIV-positive patients.

METHODS
We did a diagnostic accuracy study at five outpatient public health facilities in Uganda, Kenya, Mozambique, and South Africa. Eligible patients were ambulatory HIV-positive individuals (aged ≥15 years) with symptoms of tuberculosis irrespective of their CD4 T-cell count (group 1), and asymptomatic patients with advanced HIV disease (CD4 count <200 cells per μL, or HIV clinical stage 3 or 4; group 2). All participants underwent clinical examination, chest x-ray, and blood sampling, and were requested to provide a fresh urine sample, and two sputum samples. FujiLAM and AlereLAM urine assays, Xpert MTB/RIF Ultra assay on sputum or urine, sputum culture for Mycobacterium tuberculosis, and CD4 count were systematically carried out for all patients. Sensitivity and specificity of FujiLAM and AlereLAM were evaluated against microbiological and composite reference standards.

FINDINGS
Between Aug 24, 2020 and Sept 21, 2021, 1575 patients (823 [52·3%] women) were included in the study: 1031 patients in group 1 and 544 patients in group 2. Tuberculosis was microbiologically confirmed in 96 (9·4%) of 1022 patients in group 1 and 18 (3·3%) of 542 patients in group 2. Using the microbiological reference standard, FujiLAM sensitivity was 60% (95% CI 51–69) and AlereLAM sensitivity was 40% (31–49; p<0·001). Among patients with CD4 counts of less than 200 cells per μL, FujiLAM sensitivity was 69% (57–79) and AlereLAM sensitivity was 52% (40–64; p=0·0218). Among patients with CD4 counts of 200 cells per μL or higher, FujiLAM sensitivity was 47% (34–61) and AlereLAM sensitivity was 24% (14–38; p=0·0116). Using the microbiological reference standard, FujiLAM specificity was 87% (95% CI 85–89) and AlereLAM specificity was 86% (95 CI 84–88; p=0·941). FujiLAM sensitivity varied by lot number from 48% (34–62) to 76% (57–89) and specificity from 77% (72–81) to 98% (93–99).

INTERPRETATION
Next-generation, higher sensitivity urine-lipoarabinomannan assays are potentially promising tests that allow rapid tuberculosis diagnosis at the point of care for HIV-positive patients. However, the variability in accuracy between FujiLAM lot numbers needs to be addressed before clinical use.
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