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

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.

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

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.

Integrating hepatitis C treatment into multidrug-resistant TB care.

BACKGROUND: Direct-acting antivirals (DAAs) are not widely used for patients with chronic hepatitis C virus (HCV) infection and multidrug- or rifampicin-resistant TB (MDR/RR-TB). We describe the implementation aspects of a new integrated model of care in Armenia and the perceptions of the healthcare staff and patients. METHODS: We used qualitative methods, including a desktop review and semi-structured individual interviews with healthcare staff and with patients receiving HCV and MDR/RR-TB treatment. RESULTS: The new integrated model resulted in simplified management of HCV and MDR/RR-TB at public TB facilities. Training on HCV was provided for TB clinic staff. All MDR/RR-TB patients were systematically offered HCV testing and those diagnosed with HCV, offered treatment with DAAs. Treatment monitoring was performed by TB staff in coordination with a hepatologist. The staff interviewed had a positive opinion of the new model. They suggested that additional training should be provided. Most patients were fully satisfied with the care received. Some were concerned about the increased pill burden. CONCLUSION: Integrating HCV treatment into MDR/ RR-TB care was feasible and appreciated by patients and staff. This new model facilitated HCV diagnosis and treatment among people with MDR/RR-TB. Our results encourage piloting this model in other settings.

CONTEXTE: Les antiviraux à action directe (DAA) sont peu prescrits aux patients atteints d'hépatite C (HCV) chronique et de TB multirésistante ou résistante à la rifampicine (MDR/RR-TB). Nous décrivons la mise en place d'un nouveau modèle de soins intégrés en Arménie, ainsi que l'opinion du personnel soignant et des patients. MÉTHODES: Nous avons utilisé des méthodes qualitatives, comprenant un examen électronique de la documentation et des entretiens individuels semi-structurés avec le personnel soignant et les patients sous traitement pour HCV et MDR/RR-TB. RÉSULTATS: Le nouveau modèle intégré a permis de simplifier la prise en charge du HCV et de la MDR/RR-TB dans les centres de soins publics de la TB. Une formation sur le HCV a été dispensée au personnel des centres antituberculeux. Tous les patients atteints de MDR/RR-TB se sont vu systématiquement proposer un test de dépistage du HCV, et un traitement par DAA a été proposé à ceux dont le résultat était positif. Le suivi du traitement a été réalisé par le personnel des centres antituberculeux, conjointement à un hépatologue. Les membres du personnel interrogés avaient une opinion positive du nouveau modèle et suggéraient de dispenser d'autres formations. La plupart des patients étaient pleinement satisfaits des soins reçus, mais certains étaient inquiets au vu du nombre accru de comprimés à prendre. CONCLUSION: L'intégration du traitement du HCV aux soins de la MDR/RR-TB s'est avérée possible et a été appréciée par les patients et le personnel soignant. Ce nouveau modèle a facilité le diagnostic et le traitement du HCV chez les patients atteints de MDR/RR-TB. Ce modèle devrait être testé dans d'autres contextes.

Clinical perspectives on treatment of rifampicin-resistant/multidrug-resistant TB.

Rapid diagnostics, newer drugs, repurposed medications, and shorter regimens have radically altered the landscape for treating rifampicin-resistant TB (RR-TB) and multidrug-resistant TB (MDR-TB). There are multiple ongoing clinical trials aiming to build a robust evidence base to guide RR/MDR-TB treatment, and both observational studies and programmatic data have contributed to advancing the treatment field. In December 2019, the WHO issued their second 'Rapid Communication´ related to RR-TB management. This reiterated their prior recommendation that a majority of people with RR/MDR-TB receive all-oral treatment regimens, and now allow for specific shorter duration regimens to be used programmatically as well. Many TB programs need clinical advice as they seek to roll out such regimens in their specific setting. In this Perspective, we highlight our early experiences and lessons learned from working with National TB Programs, adult and pediatric clinicians and civil society, in optimizing treatment of RR/MDR-TB, using shorter, highly-effective, oral regimens for the majority of people with RR/MDR-TB.

Introducing new and repurposed TB drugs: the endTB experience.

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.

Setting up pharmacovigilance based on available endTB Project data for bedaquiline.

SETTING: Active pharmacovigilance (PV) is recommended for TB programmes, notably for multidrug-resistant TB (MDR-TB) patients treated with new drugs. Launched with the support of UNITAID in April 2015, endTB (Expand New Drug markets for TB) facilitated treatment with bedaquiline (BDQ) and/or delamanid of >2600 patients in 17 countries, and contributed to the creation of a central PV unit (PVU).OBJECTIVE: To explain the endTB PVU process by describing the serious adverse events (SAEs) experienced by patients who received BDQ-containing regimens.DESIGN: The overall PV strategy was in line with the 'advanced´ WHO active TB drug safety monitoring and management (aDSM) system. All adverse events (AEs) of clinical significance were followed up; the PVU focused on signal detection from SAEs.RESULTS and CONCLUSION: Between 1 April 2015 and 31 March 2019, the PVU received and assessed 626 SAEs experienced by 417 BDQ patients. A board of MDR-TB/PV experts reviewed unexpected and possibly drug-related SAEs to detect safety signals. The experts communicated on clusters of risks factors, notably polypharmacy and off-label drug use, encouraging a patient-centred approach of care. Organising advanced PV in routine care is possible but demanding. It is reasonable to expect local/national programmes to focus on clinical management, and to limit reporting to aDSM systems to key data, such as the SAEs.

What is the best culture conversion prognostic marker for patients treated for multidrug-resistant tuberculosis?

INTRODUCTION: Identification of good prognostic marker for tuberculosis (TB) treatment response is a necessary step on the path towards a surrogate marker to reduce TB trial duration.METHODS: We performed a retrospective analysis on routinely collected data in 6 drug-resistant TB (DRTB) programs. Culture conversion, defined as two consecutive negative cultures, was assessed, and performance of culture conversion at Month 2 and Month 6 to predict treatment success were explored. To explore factors associated with positive predicted value (PPV) and the specificity of culture conversion, a multinomial logistic regression was fitted.RESULTS: This study included 634 patients: 68.5% were males; the median age was 35 years, 75.2% were previously treated for TB, 59.4% were resistant only to isoniazid and rifampicin and 18.1% resistant to fluoroquinolones. Culture conversion at Month 2 and 6 showed similar PPV while specificity was much higher for culture conversion at Month 2: 91.3% (95%CI 86.1-95.1). PPV of culture conversion at Month 2 did not vary strongly according to patients' characteristics, while specificity was slightly higher among patients with fluoroquinolone-resistant strains.CONCLUSION: Culture conversion at Month 2 is an acceptable prognostic marker for MDR-TB treatment. Considering the advantage of using an earlier marker, further evaluation as a surrogate marker is warranted to shorten TB trials.

Mobile community-based active case-finding for tuberculosis among older populations in rural Cambodia.

OBJECTIVE: To systematically screen older rural populations in Cambodia for tuberculosis (TB) and develop an effective active case-finding (ACF) model for this TB high-risk group.DESIGN: A retrospective study using routinely collected programmatic data on community-based ACF among people aged ≥55 years using TB symptoms and systematic chest radiography (CXR) screening, followed by Xpert® MTB/RIF testing for participants with positive screening results and TB culture for certain Xpert-negative specimens.RESULTS: Of 22 101 participants included in the analysis, 7469 (33.8%) were screening-positive and 5960 (27.0%) underwent Xpert testing. Pulmonary TB was identified in 482 (2.2%) individuals: 288 (1.3%) were bacteriologically confirmed (253 using Xpert, 35 using culture) and 194 (0.9%) were clinically diagnosed. Eighty-seven people needed to be screened in order to diagnose one Xpert-positive case. Among the Xpert-positive cases, only 31.6% (80/253) reported cough ≥2 weeks, and 39.9% (101/253) were asymptomatic but had a CXR suggestive of active TB. Treatment uptake was 97.3% (469/482), and treatment success was 88.0% (424/482).CONCLUSIONS: Community-based ACF was effective in detecting and successfully treating older TB patients, most of whom might otherwise have remained undiagnosed. Mobile CXR appears to be crucial in identifying a high number of asymptomatic, bacteriologically confirmed cases.

Barriers and facilitators to early access of bedaquiline and delamanid for MDR-TB: a mixed-methods study.

SETTING: Phase II trials for bedaquiline (BDQ) and delamanid (DLM) were completed by 2011 and the drugs were approved by stringent regulatory authorities for the treatment of multidrug-resistant tuberculosis (MDR-TB) between 2012 and 2014. Manufacturers established 'early access' mechanisms to provide drugs before local registration. OBJECTIVE: To inform improvements in early access, we explored experiences of providers and advocates in accessing BDQ and DLM before the end of 2015 using a mixed-methods design. DESIGN: We examined barriers and facilitators to early access through an electronic survey. Barriers and facilitators were classified as occurring at the manufacturer- or country-level. We identified themes using inductive content analysis and illustrated themes through case studies. RESULTS: We analysed 41 survey responses from 36 respondents reporting on 22 countries; early access was attempted in 30 (73%) survey responses. Eligibility restrictions (11/30, 37%) and complicated and slow processes (8/30, 27%) were manufacturer-level barriers; access to companion drugs (10, 33%) and importation difficulties (4, 13%) were country-level barriers. Previous experience with manufacturer (3/30, 10%) and country processes (2/30, 7%) facilitated access. Eight case studies show the human impact of barriers and facilitators. CONCLUSION: Manufacturers and countries should develop transparent processes to permit early access, particularly for diseases that largely affect the poor, such as MDR-TB. Developers should plan for this need and rapidly register drugs with proven benefit, prioritizing high-burden settings.

Is 6 months of bedaquiline enough? Results from the compassionate use of bedaquiline in Armenia and Georgia.

BACKGROUND AND SETTING: Bedaquiline (BDQ) was initially only available through compassionate use programmes. OBJECTIVE: To assess the effectiveness and safety of multidrug-resistant tuberculosis (MDR-TB) treatment containing BDQ. METHOD: Retrospective analysis of data from patients receiving BDQ through compassionate use in Armenia and Georgia from April 2013 to April 2015. Logistic regression was used to assess the risk factors associated with unsuccessful treatment outcomes. RESULTS: Of 82 patients included, 84.2% (69/82) had fluoroquinolone-resistant MDR-TB and 43.4% (23/53) were seropositive for the hepatitis C virus (HCV). The culture conversion rate was 84.4% (54/64), and 18.5% (10/54) reverted back to positive. In total, 79.3% (65/82) of the patients reported at least one adverse event. Serious adverse events were reported in 14 patients, with 10/14 patients experiencing fatal outcomes-6/10 related to advanced TB and 2/10 assessed as possibly related to BDQ. Treatment outcomes were as follows: 58.5% treatment success, 12.2% deaths, 7.3% failures and 21.9% lost to follow-up. HCV coinfection was associated with unsuccessful outcomes (adjusted OR 4.45, 95%CI 1.23-16.13). CONCLUSION: BDQ through compassionate use showed relatively good success rates and safety profiles in a cohort with difficult-to-treat MDR-TB. High rates of reversion may indicate that >24 weeks of BDQ is necessary in some cases. HCV coinfection should be diagnosed and treatment considered in MDR-TB patients.

Examples of bedaquiline introduction for the management of multidrug-resistant tuberculosis in five countries.

BACKGROUND: For the first time in almost 50 years, there are new drugs available for the treatment of tuberculosis (TB), including bedaquiline (BDQ) and delamanid (DLM). The rate of introduction, however, has not kept pace with patient needs. It is estimated that as many as 23% of multidrug-resistant TB (MDR-TB) patients have an indication for receiving BDQ. As this is the first time the MDR-TB community is introducing new medications, it is important to understand how implementation can be developed in a variety of settings. METHODS: A qualitative assessment of country TB programs in which more than 5% of MDR-TB patients were started on BDQ under program conditions. RESULTS: National TB programs in Belarus, France, Georgia, South Africa, and Swaziland all started sizeable cohorts of patients on BDQ in 2015. Common factors observed in these programs included experience with compassionate use/expanded access, support from implementing partners, and adequate national or donor-supported budgets. Barriers to introduction included restriction of BDQ to the in-patient setting, lack of access to companion drugs, and the development of systems for pharmacovigilance. CONCLUSION: The five countries in this paper are examples of the introduction of new therapeutic options for the treatment of TB.

Analysis of 3D strain in the human medial meniscus.

This study presents a method to evaluate three-dimensional strain in meniscal tissue using medical imaging. Strain is calculated by tracking small teflon markers implanted within the meniscal tissue using computed tomography imaging. The results are presented for strains in the middle and posterior third of the medial menisci of 10 human cadaveric knees, under simulated physiologically relevant loading. In the middle position, an average compressive strain of 3.4% was found in the medial-lateral direction, and average tensile strains of 1.4% and 3.5% were found in the anterior-posterior and superior-inferior directions respectively at 5° of knee flexion with an applied load of 1× body weight. In the posterior position, under the same conditions, average compressive strains of 2.2% and 6.3% were found in the medial-lateral and superior-inferior directions respectively, and an average tensile strain of 3.8% was found in the anterior-posterior direction. No statistically significant difference between strain in the middle or posterior of the meniscus or between the global strains is uncovered.

Identification of patients who could benefit from bedaquiline or delamanid: a multisite MDR-TB cohort study.

BACKGROUND: The World Health Organization recommends adding bedaquiline or delamanid to multidrug-resistant tuberculosis (MDR-TB) regimens for which four effective drugs are not available, and delamanid for patients at high risk of poor outcome. OBJECTIVE: To identify patients at risk of unfavourable outcomes who may benefit from the new drugs. METHODS: Retrospective cohort study of treatment outcomes involving four to five effective drugs for 15-24 months in programmes in Uzbekistan, Georgia, Armenia, Swaziland and Kenya between 2001 and 2011. RESULTS: Of 1433 patients, 48.5% had body mass index (BMI) <18.5 kg/m(2), 72.9% had a high bacillary load, 16.7% were resistant to two injectables, 2.9% were resistant to ofloxacin (OFX) and 3.0% had extensively drug-resistant TB (XDR-TB). Treatment success ranged from 59.7% (no second-line resistance) to 27.0% (XDR-TB). XDR-TB (aOR 8.16, 95%CI 3.22-20.64), resistance to two injectables (aOR 1.90, 95%CI 1.00-3.62) or OFX (aOR 5.56, 95%CI 2.15-14.37), past incarceration (aOR 1.88, 95%CI 1.11-3.2), history of second-line treatment (aOR 3.24, 95%CI 1.53-6.85), low BMI (aOR 2.22, 95%CI 1.56-3.12) and high bacillary load (aOR 2.32, 95%CI 1.15-4.67) were associated with unfavourable outcomes. Patients started on capreomycin rather than kanamycin were more likely to have an unfavourable outcome (aOR 1.54, 95%CI 1.04-2.28). CONCLUSION: In our cohort, patients who may benefit from bedaquiline and delamanid represented up to two thirds of all MDR-TB patients.

Tuberculosis treatment in a refugee and migrant population: 20 years of experience on the Thai-Burmese border.

SETTING: Although tuberculosis (TB) is a curable disease, it remains a major global health problem and an important cause of morbidity and mortality among vulnerable populations, including refugees and migrants. OBJECTIVE: To describe results and experiences over 20 years at a TB programme in refugee camps on the Thai-Burmese border in Tak Province, Thailand, and to identify risk factors associated with adverse outcomes (e.g., default, failure, death). DESIGN: Retrospective review of routine records of 2425 patients admitted for TB treatment in the Mae La TB programme between May 1987 and December 2005. RESULTS: TB cases notified among refugees decreased over 20 years. Among patients treated with a first-, second- or third-line regimen, 77.5% had a successful outcome, 13.5% defaulted, 7.6% died and 1.3% failed treatment. Multivariate analysis for new cases showed higher likelihood of adverse outcomes for patients who were Burmese migrants or Thai villagers, male, aged >15 years or with smear-negative pulmonary TB. CONCLUSION: These findings suggest that treatment outcomes depend on the programme's capacity to respond to specific patients' constraints. High-risk groups, such as migrant populations, need a patient-centred approach, and specific, innovative strategies have to be developed based on the needs of the most vulnerable and marginalised populations.