Compassionate use of delamanid in combination with bedaquiline for the treatment of multidrug-resistant tuberculosis

Clinical outcomes of multidrug-resistant tracheobronchial tuberculosis receiving anti-tuberculosis regimens containing bedaquiline or delamanid

The treatment of multidrug-resistant tracheobronchial tuberculosis poses challenges, and research investigating the efficacy of bedaquiline or delamanid as treatment for this condition is limited. This retrospective cohort study was conducted from 2017 to 2021. The study extracted data of patients with multidrug-resistant tracheobronchial tuberculosis from medical records and followed up on prognoses. Participants were divided into three groups: the bedaquiline, delamanid, and control group. Clinical outcomes and the risk factors associated with early culture conversion were analyzed. This study included 101 patients, with 32, 25, and 44 patients in the bedaquiline, delamanid, and control groups respectively. The differences in the treatment success rates among the three groups did not show statistical significance. Both the bedaquiline and delamanid groups had significantly higher culture conversion rates compared to the control after 2 or 6 months of treatment, with significantly shorter median times to culture conversion (bedaquiline group: 2 weeks, delamanid group: 2 weeks, control group: 12 weeks, P < 0.001). Treatment with bedaquiline or delamanid were identified as independent predictors of culture conversion at 2 months (bedaquiline group: aOR = 13.417, 95% CI 4.067-44.260, delamanid group: aOR = 9.333, 95% CI 2.498-34.878) or 6 months (bedaquiline group: aOR = 13.333, 95% CI 3.379-52.610, delamanid group: aOR = 5.000, 95% CI 1.357-18.426) of treatment through multivariable logistic regression analyses. The delamanid group showed better improvement in lumen stenosis compared to bedaquiline. Regimens containing bedaquiline or delamanid may accelerate the culture conversion during the early treatment phase in multidrug-resistant tracheobronchial tuberculosis, and delamanid appears to have the potential to effectively improve airway stenosis.

Efficacy and safety of bedaquiline and delamanid in the treatment of drug-resistant tuberculosis in adults: A systematic review and meta-analysis

Multi and extensively drug-resistant tuberculosis is a grave cause of global public health concern due to its high mortality and limited treatment options. We conducted this systemic review and meta-analysis to evaluate the efficacy and safety of bedaquiline and delamanid, which have been added to the WHO-recommended regimen for treating drug-resistant tuberculosis. Electronic databases were searched from their inception until December 1st, 2021, for eligible studies assessing the efficacy and safety of bedaquiline and delamanid for treating drug-resistant tuberculosis. Binary outcomes were pooled using a DerSimonian-Laird random-effects model and arcsine transformation and reported on a log scale with a 95% confidence interval (CIs). Twenty-one studies were shortlisted in which bedaquiline, delamanid, and a combination of both were administered in 2477, 937, and 169 patients. Pooled culture conversion at 6 months was 0.801 (p < 0.001), 0.849 (p = 0.059) for bedaquiline and delamanid, respectively, and 0.823 (p = 0.017), concomitantly. In the bedaquiline cohort, the pooled proportion of all-cause mortality at 6 months was reported as 0.074 (p < 0.001), 0.031 (p = 0.372) in the delamanid cohort, and 0.172 in the combined cohort. The incidence of adverse events in the bedaquiline cohort ranged from 11.1% to 95.2%, from 13.2% to 86.2% in the delamanid cohort, and 92.5% in a study in the combined cohort. The incidence of QTC prolongation reported in each cohort is as follows: bedaquiline 0.163 (p < 0.001), delamanid 0.344 (p = 0.272) and combined 0.340 (p < 0.001). Our review establishes the efficacy of delamanid, bedaquiline, and their combined use in treating drug-resistant tuberculosis with reasonable rates of culture conversion, low mortality rates, and safety of co-administration, as seen with their effect on the QTc interval.

Advances of new drugs bedaquiline and delamanid in the treatment of multi-drug resistant tuberculosis in children

Tuberculosis (TB) is a major public health problem, with nearly 10 million new cases and millions of deaths each year. Around 10% of these cases are in children, but only a fraction receive proper diagnosis and treatment. The spread of drug-resistant (DR) strain of TB has made it difficult to control, with only 60% of patients responding to treatment. Multi-drug resistant TB (MDR-TB) is often undiagnosed in children due to lack of awareness or under-diagnosis, and the target for children's DR-TB treatment has only been met in 15% of goals. New medications such as bedaquiline and delamanid have been approved for treating DR-TB. However, due to age and weight differences, adults and children require different dosages. The availability of child-friendly formulations is limited by a lack of clinical data in children. This paper reviews the development history of these drugs, their mechanism of action, efficacy, safety potential problems and current use in treating DR-TB in children.

An update on ATP synthase inhibitors: A unique target for drug development in M. tuberculosis

ATP synthase is a key protein in the oxidative phosphorylation process, as it aids in the effective production of ATP (Adenosine triphosphate) in all life's of kingdoms. ATP synthases have distinctive properties that contribute to efficient ATP synthesis. The ATP synthase of mycobacterium is of special relevance since it has been identified as a target for potential anti-TB molecules, especially Bedaquiline (BDQ). Better knowledge of how mycobacterial ATP synthase functions and its peculiar characteristics will aid in our understanding of bacterial energy metabolism adaptations. Furthermore, identifying and understanding the important distinctions between human ATP synthase and bacterial ATP synthase may provide insight into the design and development of inhibitors that target specific ATP synthase. In recent years, many potential candidates targeting the ATP synthase of mycobacterium have been developed. In this review, we discuss the druggable targets of the Electron transport chain (ETC) and recently identified potent inhibitors (including clinical molecules) from 2015 to 2022 of diverse classes that target ATP synthase of M. tuberculosis.

Favorable outcome of individual regimens containing bedaquiline and delamanid in drug-resistant tuberculosis: A systematic review

Background

Drug-resistant tuberculosis (DR-TB) is a public health concern that is difficult to treat, requiring long and complex treatment with highly effective drugs. Bedaquiline and/or delamanid have already shown promising outcomes in patients with DR-TB, increasing the rate of culture conversion and lowering TB-related mortality.

Methods

We comprehensively searched and evaluated the effectiveness of individual regimens containing bedaquiline and delamanid on culture conversion and treatment success. We assessed for quality either observational or experimental studies.

Results

We identified 14 studies that met the inclusion criteria using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart with 12 observational and 2 experimental studies. Of 1691 DR-TB patients enrolled in the included studies, 1407 of them concomitantly received regimens containing bedaquiline and delamanid. Overall multidrug resistant (MDR), preextensively drug resistant (XDR), and XDR-TB were seen in 21.4%, 44.1%, and 34.5%, respectively. Of 14 studies, 8 of them reported favorable outcomes including sputum culture conversion and cure rate at the end of treatment, meanwhile 6 studies only reported sputum culture conversion. Sputum culture conversion at the end of the 6^th month was 63.6%-94.7% for observational studies, and 87.6%-95.0% for experimental studies. The favorable outcome at the end of treatment was 67.5%-91.4%. With high pre-XDR and XDR cases among DR-TB patients with limited treatment options, regimens containing bedaquiline and delamanid provide successful treatment.

Conclusion

In DR-TB patients receiving regimens containing bedaquiline and delamanid, favorable outcomes were high including sputum conversion and cure rate.

Delamanid-containing regimens and multidrug-resistant tuberculosis: A systematic review and meta-analysis

INTRODUCTION

Multidrug-resistant tuberculosis (MDR-TB) is a life-threatening condition needing long poly-chemotherapy regimens. As no systematic reviews/meta-analysis is available to comprehensively evaluate the role of delamanid (DLM), we evaluated its effectiveness and safety.

METHODS

We reviewed the relevant scientific literature published up to January 20, 2022. The pooled success treatment rate with 95% confidence intervals (CI) was assessed using a random-effect model. We assessed studies for quality and bias, and considered P<0.05 to be statistically significant.

RESULTS

After reviewing 626 records, we identified 25 studies that met the inclusion criteria, 22 observational and 3 experimental, with 1276 and 411 patients, respectively. In observational studies the overall pooled treatment success rate of DLM-containing regimens was 80.9% (95% CI 72.6-87.2) with no evidence of publication bias (Begg's test; P >0.05). The overall pooled treatment success rate in DLM and bedaquiline-containing regimens was 75.2% (95% CI 68.1-81.1) with no evidence of publication bias (Begg's test; P >0.05). In experimental studies the pooled treatment success rate of DLM-containing regimens was 72.5 (95% CI 44.2-89.8, P <0.001, I²: 95.1%) with no evidence of publication bias (Begg's test; P >0.05).

CONCLUSIONS

In MDR-TB patients receiving DLM, culture conversion and treatment success rates were high despite extensive resistance with limited adverse events.

Scoping review: QT interval prolongation in regimen containing bedaquiline and delamanid in patients with drug-resistant tuberculosis

Background

A regimen containing bedaquiline-delamanid is recommended in management of drug-resistant tuberculosis (DR TB) to increase a success rate. However, this regimen was rare in a clinical setting due to a potential risk of QT prolongation. Several studies have reported the incidence of QT prolongation after administration of this regimen, but the results are inconsistent due to different sample size, study design, and covariate. The aim of this review is to summarize and analyze the published articles related to QT prolongation of bedaquiline and delamanid in PubMed and ScienceDirect databases using a scoping review.

Methods

This scoping review was conducted under PRISMA for scoping review. The outcomes of this review were incidence of QT prolongation and death. We found 8 articles to be included in this review.

Results

The incidence of QT prolongation was higher for DR TB patients who received a regimen containing bedaquiline and delamanid. However, this review found no clinical symptoms, such as cardiac arrhythmias, torsade de pointes, or even death. DR TB patients, especially the elderly, were at risk for QT prolongation. Special consideration in patients with HIV and low level of potassium should be closely monitored for QT interval.

Conclusion

The regular measurement of electrocardiography was highly recommended to evaluate QT interval. Generally, the use of individualized regimen containing bedaquiline and delamanid is relatively safe in DR TB patients.

Assessing Prolongation of the Corrected QT Interval with Bedaquiline and Delamanid Coadministration to Predict the Cardiac Safety of Simplified Dosing Regimens

Delamanid and bedaquiline are two drugs approved to treat drug-resistant tuberculosis, and each have been associated with corrected QT interval (QTc) prolongation. We aimed to investigate the relationships between the drugs' plasma concentrations and the prolongation of observed QT interval corrected using Fridericia's formula (QTcF) and to evaluate their combined effects on QTcF, using a model-based population approach. Furthermore, we predicted the safety profiles of once daily regimens. Data were obtained from a trial where participants were randomized 1:1:1 to receive delamanid, bedaquiline, or delamanid + bedaquiline. The effect on QTcF of delamanid and/or its metabolite (DM-6705) and the pharmacodynamic interactions under coadministration were explored based on a published model between bedaquiline's metabolite (M2) and QTcF. The metabolites of each drug were found to be responsible for the drug-related QTcF prolongation. The final drug-effect model included a competitive interaction between M2 and DM-6705 acting on the same cardiac receptor and thereby reducing each other's apparent potency, by 28% (95% confidence interval (CI), 22-40%) for M2 and 33% (95% CI, 24-54%) for DM-6705. The generated combined effect was not greater but close to "additivity" in the analyzed concentration range. Predictions with the final model suggested a similar QT prolonging potential with simplified, once-daily dosing regimens compared with the approved regimens, with a maximum median change from baseline QTcF increase of 20 milliseconds in both regimens. The concentrations-QTcF relationship of the combination of bedaquiline and delamanid was best described by a competitive binding model involving the two main metabolites. Model predictions demonstrated that QTcF prolongation with simplified once daily regimens would be comparable to currently used dosing regimens.

Safety and effectiveness outcomes from a 14-country cohort of patients with multi-drug resistant tuberculosis treated concomitantly with bedaquiline, delamanid and other second-line drugs

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 patients (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.

Exposure-safety analysis of QTc interval and transaminase levels following bedaquiline administration in patients with drug-resistant tuberculosis

Bedaquiline (BDQ) has shown great value in the treatment of multidrug‐resistant tuberculosis (MDR‐TB) in recent years. However, exposure–safety relationships must be explored to extend the use of BDQ. Two reported safety findings for BDQ are prolongation of the QTc interval and elevation of transaminase levels. In this study, we investigated the potential relationships between BDQ and/or its main metabolite (M2) pharmacokinetic (PK) metrics and QTcF interval or transaminase levels in patients with MDR‐TB using the approved dose regimen. Data from 429 patients with MDR‐TB from two phase IIb studies were analyzed via nonlinear mixed‐effects modeling. Individual model‐predicted concentrations and summary PK metrics were evaluated, respectively, in the QTcF interval and transaminase level exposure–response models. Investigation of further covariate effects was performed in both models. M2 concentrations were found to be responsible for the drug‐related QTcF increase in a model accounting for circadian rhythm patterns, time on study, effect of concomitant medication with QT liability, and patient demographics. Simulations with the final model suggested that doses higher than the approved dose (leading to increased M2 concentrations) are not expected to lead to a critical QTcF interval increase. No exposure–safety relationship could be described with transaminase levels despite previous reports of higher levels in patients treated with BDQ. The developed longitudinal models characterized the role of M2 concentrations in QTc interval prolongation and found no concentration dependency for transaminase level elevation, together suggesting that BDQ exposure at the high end of the observed range may not be associated with a higher risk of safety events.

QT effects of bedaquiline, delamanid, or both in patients with rifampicin-resistant tuberculosis: a phase 2, open-label, randomised, controlled trial

BACKGROUND

Bedaquiline and delamanid are the first drugs of new classes registered for tuberculosis treatment in 40 years. Each can prolong the QTc interval, with maximum effects occurring weeks after drug initiation. The cardiac safety and microbiological activity of these drugs when co-administered are not well-established. Our aim was to characterise the effects of bedaquiline, delamanid, or both on the QTc interval, longitudinally over 6 months of multidrug treatment, among patients with multidrug-resistant or rifampicin-resistant tuberculosis taking multidrug background therapy.

METHODS

ACTG A5343 is a phase 2, open-label, randomised, controlled trial in which adults with multidrug-resistant or rifampicin-resistant tuberculosis receiving multidrug background treatment were randomly assigned 1:1:1 by centrally, computer-generated randomisation, by means of permuted blocks to receive bedaquiline, delamanid, or both for 24 weeks. Participants were enrolled at TASK in Cape Town and the South African Tuberculosis Vaccine Initiative in Worcester, both in South Africa, and Hospital Maria Auxiliadora in Peru. Individuals with QTc greater than 450 ms were excluded. HIV-positive participants received dolutegravir-based antiretroviral therapy. Clofazimine was disallowed, and levofloxacin replaced moxifloxacin. ECG in triplicate and sputum cultures were done fortnightly. The primary endpoint was mean QTcF change from baseline (averaged over weeks 8-24); cumulative culture conversation at week 8-24 was an exploratory endpoint. Analyses included all participants who initiated study tuberculosis treatment (modified intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT02583048 and is ongoing.

FINDINGS

Between Aug 26, 2016 and July 13, 2018, of 174 screened, 84 participants (28 in each treatment group, and 31 in total with HIV) were enrolled. Two participants did not initiate study treatment (one in the delamanid group withdrew consent and one in the bedaquiline plus delamanid group) did not meet the eligibility criterion). Mean change in QTc from baseline was 12·3 ms (95% CI 7·8-16·7; bedaquiline), 8·6 ms (4·0-13·1; delamanid), and 20·7 ms (16·1-25·3) (bedaquiline plus delamanid). There were no grade 3 or 4 adverse QTc prolongation events and no deaths during study treatment. Cumulative culture conversion by week 8 was 21 (88%) of 24 (95% CI 71-97; bedaquiline), 20 (83%) of 24 (65-95; delamanid), and 19 (95%) of 20 (79-100; bedaquiline plus delamanid) and was 92% (77-99) for bedaquiline, 91% (76-99), for delamanid, and 95% (79-100) for bedaquiline plus delamanid at 24 weeks.

INTERPRETATION

Combining bedaquiline and delamanid has a modest, no more than additive, effect on the QTc interval, and initial microbiology data are encouraging. This study provides supportive evidence for use of these agents together in patients with multidrug-resistant or rifampicin-resistant tuberculosis with normal baseline QTc values.

FUNDING

Division of AIDS, National Institutes of Health.

Superior efficacy of a bedaquiline, delamanid and linezolid combination regimen in a mouse-TB model

BACKGROUND

The treatment success rate of drug-resistant tuberculosis (DR-TB) is alarmingly low. Therefore, more effective and less complex regimens are urgently required.

METHODS

We compared the efficacy of an all oral DR-TB drug regimen consisting of bedaquiline (25 mg/kg), delamanid (2.5 mg/kg) and linezolid (100 mg/kg) (BDL) on the mycobacterial load in the lungs and spleen of TB infected mice during a treatment period of 24 weeks. This treatment was compared to the standard regimen of isoniazid, rifampicin, pyrazinamide and ethambutol (HRZE). Relapse was assessed 12 weeks post-treatment. Two logistic regression models were developed to compare the efficacy of both regimens.

RESULTS

Culture negativity in the lungs was achieved at 8 and 20 weeks of treatment with BDL and HRZE, respectively. After 14 weeks of treatment only one mouse relapsed in the BDL group, while in the HRZE group relapse was still observed at 24 weeks of treatment. Predictions from the final mathematical models showed that a 95% cure rate was reached after 20.5 and 28.5 weeks of treatment with BDL and HRZE, respectively.

CONCLUSION

The BDL regimen was observed to be more effective than HRZE and could be a valuable option for the treatment of DR-TB.

Compassionate use of delamanid in adults and children for drug-resistant tuberculosis: 5-year update

BACKGROUND

Although delamanid has been approved for the treatment of multidrug-resistant TB (MDR-TB) in numerous regions, in areas where it is not yet registered it can be accessed as part of salvage therapy (in particular for those patients with limited treatment options) via the Otsuka compassionate use programme. Here we present the analysis of interim treatment outcomes by 24 weeks of more than 200 MDR-TB patients globally who received delamanid under this programme.

METHODS

We evaluated treatment efficacy with respect to culture negativity at 24 weeks, as well as the safety profile of delamanid, in an MDR-TB patient cohort treated under compassionate use between 2014 and 2019.

RESULTS

Among patients who received delamanid as part of a multidrug regimen, 123 (61%) out of 202 had extensively drug-resistant TB (XDR-TB), 66 (33%) out of 202 had HIV co-infection and 34 (17%) out of 202 were children aged between 6 and 17 years. Of those patients who were culture positive at delamanid treatment initiation and who completed 24 weeks of delamanid treatment in combination with other anti-tuberculosis (TB) drugs, culture negativity was achieved in 116 (79%) out of 147 cases. The corresponding rates of culture negativity for patients with XDR-TB and HIV co-infection, as well as the paediatric subgroup were 69 (77%) out of 90, 44 (92%) out of 48 and 20 (80%) out of 25, respectively. QT interval prolongation was the most frequently observed serious adverse event and was reported in 8% of patients receiving delamanid. Overall, treatment safety outcomes did not reveal any new or unidentified risks.

CONCLUSIONS

The use of delamanid combined with other active drugs has the potential to achieve high rates of culture negativity in difficult-to-treat drug-resistant TB cases, with a favourable safety profile.

Bedaquiline and delamanid for drug-resistant tuberculosis: a clinician's perspective

Drug-resistant tuberculosis (TB) represents a substantial threat to the global efforts to control this disease. After decades of stagnation, the treatment of drug-resistant TB is undergoing major changes: two drugs with a new mechanism of action, bedaquiline and delamanid, have been approved by stringent regulatory authorities and are recommended by the WHO. This narrative review summarizes the evidence, originating from both observational studies and clinical trials, which is available to support the use of these drugs, with a focus on special populations. Areas of uncertainty, including the use of the two drugs together or for prolonged duration, are discussed. Ongoing clinical trials are aiming to optimize the use of bedaquiline and delamanid to shorten the treatment of drug-resistant TB.

Interim treatment outcomes in multidrug-resistant tuberculosis patients treated sequentially with bedaquiline and delamanid

OBJECTIVES

The objective of this study was to evaluate the efficacy and safety of the sequential use of bedaquiline (Bdq) and delamanid (Dlm) in patients with multidrug-resistant tuberculosis (MDR-TB) and limited treatment options.

METHODS

This study evaluated 74 MDR-TB patients treated between March 2016 and December 2018 with Bdq followed by Dlm (n = 22), or vice versa (n= 52), combined with optimized background regimens.

RESULTS

The mean age of the participants was 49.0 ± 15.8 years. Fifty-one (68.9%) of the participants were male. Fluoroquinolone resistance was identified in 54 (72.9%) patients, including 20 (27.0%) with extensively drug-resistant TB. Of the 47 (63.5%) patients with positive cultures at the commencement of the first new drug, culture conversion occurred in 44 (93.6%). The interim treatment outcome after 12 months was favourable in 68/74 patients (91.9%). Twenty-four weeks of treatment were completed in 137 of 148 episodes of new drug use (92.3%). Regarding the 11 early discontinuation events, six patients stopped using a new drug due to adverse drug reactions that were not life-threatening, including one (1.4%) who stopped Bdq due to QT-prolongation.

CONCLUSIONS

Sequential use of the two new drugs appears to be an effective and safe option for MDR-TB patients with few treatment options.

Integration of drug safety monitoring in tuberculosis treatment programmes: country experiences

New drugs and shorter treatments for drug-resistant tuberculosis (DR-TB) have become available in recent years and active pharmacovigilance (PV) is recommended by the World Health Organization (WHO) at least during the early phases of implementation, with active drug safety monitoring and management (aDSM) proposed for this. We conducted a literature review of papers reporting on aDSM. Up to 18 April, 2019, results have only been published from one national aDSM programme. Because aDSM is being introduced in many low- and middle-income countries, we also report experiences in introducing it into DR-TB treatment programmes, targeting the reporting of a restricted set of adverse events (AEs) as per WHO-recommended aDSM principles for the period 2014-2017. Early beneficial effects of active PV for TB patients include increased awareness about the occurrence, detection and management of AEs during TB treatment, and the increase of spontaneous reporting in some countries. However, because PV capacity is low in most countries and collaboration between national TB programmes and national PV centres remains weak, parallel and coordinated co-development of the capacities of both TB programmes and PV centres is needed.

Telemedicine in Resource-Limited Settings to Optimize Care for Multidrug-Resistant Tuberculosis

The emergence and spread of multidrug-resistant tuberculosis (MDR-TB) poses a major threat to the global targets for TB control. In recent years, an evolving science and evidence base for MDR-TB has led to much needed changes in international guidelines promoting the use of newer TB drugs and regimens for MDR-TB, however, there remains a significant implementation gap. Due to the complexity of treating MDR-TB, management of cases is often supported by an expert multidisciplinary team, or clinical expert group. This service is often centralized, and may be delivered through a telemedicine platform. We have implemented a Web-based "store-and-forward" telemedicine service to optimize MDR-TB patient care in Daru, a remote and resource limited setting in Papua New Guinea (PNG). From April 2016 to February 2019, 237 cases were discussed using the service. This encompassed diagnostic (presumptive) and treatment cases, and more recently, support to the scale up of preventative therapy for latent TB infection. There were 75 cases in which the use of Bedaquiline was discussed or mentioned, with a high frequency of discussions occurring in the initial period (26 cases in the first 12 months), which has appeared to decrease as clinicians gained familiarity with use of the drug (15 cases in the last 12 months). This service has supported high quality clinical care and fostered collaboration between clinicians and technical experts in a shared learning environment.