Stable, compounded bedaquiline suspensions to support practical implementation of pediatric dosing in the field.

BACKGROUND: Bedaquiline (BDQ) tablets are indicated as part of a combination regimen for the treatment of multidrug-resistant TB in adults, adolescents and children. A dispersible tablet formulation is now approved but is not currently available in all settings. The aim of this study was to develop stable extemporaneous liquid formulations of BDQ that can be stored at room temperature or 30°C for several weeks, to support pragmatic pediatric dosing in the field and reduce wastage.METHODS: BDQ tablets were suspended in simple syrup and a sugar-free vehicle. Each 20 mg/mL formulation was stored at room temperature or 30°C for 30 days in amber dispensing bottles. Appearance, BDQ potency, pH and microbial counts were determined on Days 0, 15 and 30.RESULTS: The BDQ potency in both formulations remained at 98-101% of the theoretical concentration for 30 days. The appearance, pH and microbial count of sugar-free formulation did not change during the 30-day storage. The simple syrup formulation was stable for 15 days as microbial growth was observed on Day 30.CONCLUSIONS: BDQ may be prepared in syrup or sugar-free suspensions: syrup suspensions can be stored for 15 days at room temperature and 30C, whereas sugar-free suspensions can be stored for 30 days at room temperature and 30C. This information will support practical BDQ dosing for children in the field.

Multidisciplinary management of difficult-to-treat drug resistant tuberculosis: a review of cases presented to the national consilium in Uganda.

BACKGROUND: Patients with drug resistant tuberculosis (DR-TB) with comorbidities and drug toxicities are difficult to treat. Guidelines recommend such patients to be managed in consultation with a multidisciplinary team of experts (the "TB consilium") to optimise treatment regimens. We describe characteristics and treatment outcomes of DR-TB cases presented to the national DR-TB consilium in Uganda between 2013 and 2019. METHODS: We performed a secondary analysis of data from a nation-wide retrospective cohort of DR-TB patients with poor prognostic indicators in Uganda. Patients had a treatment outcome documented between 2013 and 2019. Characteristics and treatment outcomes were compared between cases reviewed by the consilium with those that were not reviewed. RESULTS: Of 1,122 DR-TB cases, 189 (16.8%) cases from 16 treatment sites were reviewed by the consilium, of whom 86 (45.5%) were reviewed more than once. The most frequent inquiries (N = 308) from DR-TB treatment sites were construction of a treatment regimen (38.6%) and management of side effects (24.0%) while the most frequent consilium recommendations (N = 408) were a DR-TB regimen (21.7%) and "observation while on current regimen" (16.6%). Among the cases reviewed, 152 (80.4%) were from facilities other than the national referral hospital, 113 (61.1%) were aged ≥ 35 years, 72 (40.9%) were unemployed, and 26 (31.0%) had defaulted antiretroviral therapy. Additionally, 141 (90.4%) had hepatic injury, 55 (91.7%) had bilateral hearing loss, 20 (4.8%) had psychiatric symptoms and 14 (17.7%) had abnormal baseline systolic blood pressure. Resistance to second-line drugs (SLDs) was observed among 9 (4.8%) cases while 13 (6.9%) cases had previous exposure to SLDs. Bedaquiline (13.2%, n = 25), clofazimine (28.6%, n = 54), high-dose isoniazid (22.8%, n = 43) and linezolid (6.7%, n = 13) were more frequently prescribed among cases reviewed by the consilium than those not reviewed. Treatment success was observed among 126 (66.7%) cases reviewed. CONCLUSION: Cases reviewed by the consilium had several comorbidities, drug toxicities and a low treatment success rate. Consilia are important "gatekeepers" for new and repurposed drugs. There is need to build capacity of lower health facilities to construct DR-TB regimens and manage adverse effects.

Repurposing Bedaquiline for Effective Non-Small Cell Lung Cancer (NSCLC) Therapy as Inhalable Cyclodextrin-Based Molecular Inclusion Complexes.

There is growing evidence that repurposed drugs demonstrate excellent efficacy against many cancers, while facilitating accelerated drug development process. In this study, bedaquiline (BDQ), an FDA approved anti-mycobacterial agent, was repurposed and an inhalable cyclodextrin complex formulation was developed to explore its anti-cancer activity in non-small cell lung cancer (NSCLC). A sulfobutyl ether derivative of ß-cyclodextrin (SBE-ß-CD) was selected based on phase solubility studies and molecular modeling to prepare an inclusion complex of BDQ and cyclodextrin. Aqueous solubility of BDQ was increased by 2.8 × 103-fold after complexation with SBE-ß-CD, as compared to its intrinsic solubility. Solid-state characterization studies confirmed the successful incorporation of BDQ in the SBE-ß-CD cavity. In vitro lung deposition study results demonstrated excellent inhalable properties (mass median aerodynamic diameter: 2.9 ± 0.6 µm (<5 µm) and fine particle fraction: 83.3 ± 3.8%) of BDQ-CD complex. Accelerated stability studies showed BDQ-CD complex to be stable up to 3 weeks. From cytotoxicity studies, a slight enhancement in the anti-cancer efficacy was observed with BDQ-cyclodextrin complex, compared to BDQ alone in H1299 cell line. The IC50 values for BDQ and BDQ-CD complex were found to be ~40 µM in case of H1299 cell line at 72 h, whereas BDQ/BDQ-CD were not found to be cytotoxic up to concentrations of 50 µM in A549 cell line. Taken together, BDQ-CD complex offers a promising inhalation strategy with efficient lung deposition and cytotoxicity for NSCLC treatment.

A systematic review of pharmacoeconomic evaluations on oral diarylquinoline-based treatment for drug-resistant tuberculosis: from high to low burden countries.

Introduction: There is a rising global interest in the pharmacoeconomic evaluations of bedaquiline (BDQ), a novel oral diarylquinoline, for treatment of drug-resistant tuberculosis (DR-TB).Areas covered: This article systematically reviewed publications retrieved from Medline, American Psychological Association-Psychology information, Web of Science, Embase, Scopus, Science direct, Center for Reviews and Dissemination, and CINAHL Complete during 2010-2020 on pharmacoeconomic studies on BDQ for DR-TB treatment. Ten Markov model-based cost-effectiveness analyses identified were conducted in high (n = 4), intermediate (n = 2), and low (n = 4) TB burden countries.Expert opinion: The paucity of model-based health economic analyses on BDQ-containing regimens for DR-TB indicated that further pharmacoeconomic research of BDQ-based regimens, on the aspects of duration of BDQ treatment, types of DR-TB indicated, and settings of regions and health-systems, is highly warranted to inform global cost-effective use of BDQ-based regimens for DR-TB treatment.

Early outcome and safety of bedaquiline-containing regimens for treatment of MDR- and XDR-TB in China: a multicentre study.

OBJECTIVES: Bedaquiline treatment significantly improves multidrug-resistant tuberculosis (MDR-TB) patient treatment outcomes. However, safety and efficacy data are lacking for bedaquiline used with background regimens to treat Chinese TB patients. Here, we describe our initial clinical experience for bedaquiline treatment of a large multicentre cohort of MDR-TB and extensively drug-resistant tuberculosis (XDR-TB) patients in China. METHODS: Patients (177) received 24-week bedaquiline treatment combined with personalized anti-TB drug background regimens. As primary efficacy endpoints, times to initial sputum culture conversion were measured. RESULTS: Of 177 MDR-TB patients completing the 24-week treatment course, sputum culture conversion occurred for 151/177 (85.3%), while 26 had unfavourable outcomes, including 3/177 (1.7%) deaths and 23/177 (13.0%) non-responders at treatment completion. The median time to sputum culture conversion was 4 (interquartile range 2-8) weeks. Conversion rates were 33/39 (84.6%, 95% confidence interval (CI) 73.3-95.9) for MDR-TB patients, 47/56 (83.9%, 95% CI 74.3-93.6) for pre-XDR-TB patients and 71/82 (86.6%, 95% CI 79.2-94.0) for XDR-TB patients. Multivariate analysis demonstrated that patients with low body mass index (odds ratio 7.356; 95% CI 2.652-20.401) were at significantly high risk of unfavourable outcomes, with serious adverse events noted in 15 (8.5%) patients, including six with corrected QT interval (QTc) prolongation times (>500 ms). CONCLUSION: Bedaquiline, when included in background regimens for treatment of MDR-TB and XDR-TB patients in China, was safe and associated with a high rate of culture conversion.

Emergence of nontuberculous mycobacteria infections during bedaquiline-containing regimens in multidrug-resistant tuberculosis patients.

OBJECTIVES: The World Health Organization recommends the use of bedaquiline (BDQ) to formulate efficacious combination regimens against multidrug-resistant tuberculosis (MDR-TB). This study reports, for the first time, a case series of MDR-TB patients treated with BDQ who experienced sputum culture reconversion due to emergence of nontuberculous mycobacteria (NTM) infections. METHODS: A multicentre case series was established, including patients who started treatment for laboratory-confirmed MDR-TB between January 1, 2018 and March 31, 2020. The study included patients with positive cultures that had no expression of tuberculosis-specific MPT64 protein. Multilocus sequence analysis was used to perform rapid species identification. Susceptibility to BDQ was detected using Thermo Fisher frozen microtiter plates by the laboratory staff at Beijing Chest Hospital. RESULTS: Among the 286 patients receiving BDQ regimens included in this study, the emergence of NTM isolations was reported in nine cases (3.1%). After exposure to BDQ, seven out of these nine patients achieved culture conversion by 4 weeks. The median time for reported NTM infection was 12 weeks (range: 4-24 weeks). Of these, seven were rapidly growing mycobacteria, and two were slow growing. The most frequent NTM species was M. abscessus (five isolates), followed by M. fortuitum (two isolates), M. avium (one isolate), and M. intracellulare (one isolate). In addition, three patients showed resistance to BDQ at baseline. CONCLUSION: In conclusion, our results demonstrated the emergence of novel NTM populations in MDR-TB patients during BDQ therapy. The notably rapid development of NTM infections underlines the need for systematic species identification during the follow-up period.

Outcomes and adverse events of pre- and extensively drug-resistant tuberculosis patients in Kinshasa, Democratique Republic of the Congo: A retrospective cohort study.

BACKGROUND: Extensively drug-resistant tuberculosis (XDR TB) is a very serious form of tuberculosis that is burdened with a heavy mortality toll, especially before the advent of new TB drugs. The Democratic Republic of the Congo (DRC) is among the countries most affected by this new epidemic. METHODS: A retrospective analysis was performed of the records of all patients with pre- and extensively drug-resistant tuberculosis hospitalized from January 1, 2015 to December 31, 2017 and monitored for at least 6 months to one year after the end of their treatment in Kinshasa; an individualized therapeutic regimen with bedaquiline for 20 months was built for each patient. The adverse effects were systematically monitored. RESULTS: Of the 40 laboratory-confirmed patients, 32 (80%) patients started treatment, including 29 preXRB and 3 XDR TB patients. In the eligible group, 3 patients (9.4%) had HIV-TB coinfections. The therapeutic success rate was 53.2%, and the mortality rate was 46.8% (15/32); there were no relapses, failures or losses to follow-up. All coinfected HIV-TB patients died during treatment. The cumulative patient survival rate was 62.5% at 3 months, 53.1% at 6 months and 53.1% at 20 months. The most common adverse events were vomiting, Skin rash, anemia and peripheral neuropathy. CONCLUSION: The new anti-tuberculosis drugs are a real hope for the management of Drug Resistant tuberculosis patient and other new therapeutic combinations may improve favorable outcomes.

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.

The cost-effectiveness of a bedaquiline-containing short-course regimen for the treatment of multidrug-resistant tuberculosis in South Africa.

Background: Bedaquiline-containing regimens have demonstrated improved outcomes over injectable-containing regimens in the long-term treatment of multidrug-resistant tuberculosis (MDR-TB). Recently, the World Health Organization (WHO) recommended replacing injectables in the standard short-course regimen (SCR) with a bedaquiline-containing regimen. The South African national TB program similarly recommends a bedaquiline-containing regimen. Here, we investigated the cost-effectiveness of a bedaquiline-containing SCR versus an injectable-containing SCR for the treatment of MDR-TB in South Africa.Methods: A Markov model was adapted to simulate the incidence of active patients with MDR-TB. Patients could transition through eight health states: active MDR-TB, culture conversion, cure, follow-up loss, secondary MDR-TB, extensively DR-TB, end-of-life care, and death. A 5% discount was assumed on costs and outcomes. Health outcomes were expressed as disability-adjusted life years (DALYs).Results: Over a 10-year time horizon, a bedaquiline-containing SCR dominated an injectable-containing SCR, with an incremental saving of US $982 per DALY averted. A bedaquiline-containing SCR was associated with lower total costs versus an injectable-containing SCR (US $597 versus $657 million), of which US $3.2 versus $21.9 million was attributed to adverse event management.Conclusions: Replacing an injectable-containing SCR with a bedaquiline-containing SCR is cost-effective, offering a cost-saving alternative with improved patient outcomes for MDR-TB.

Treatment of Highly Drug-Resistant Pulmonary Tuberculosis.

BACKGROUND: Patients with highly drug-resistant forms of tuberculosis have limited treatment options and historically have had poor outcomes. METHODS: In an open-label, single-group study in which follow-up is ongoing at three South African sites, we investigated treatment with three oral drugs - bedaquiline, pretomanid, and linezolid - that have bactericidal activity against tuberculosis and to which there is little preexisting resistance. We evaluated the safety and efficacy of the drug combination for 26 weeks in patients with extensively drug-resistant tuberculosis and patients with multidrug-resistant tuberculosis that was not responsive to treatment or for which a second-line regimen had been discontinued because of side effects. The primary end point was the incidence of an unfavorable outcome, defined as treatment failure (bacteriologic or clinical) or relapse during follow-up, which continued until 6 months after the end of treatment. Patients were classified as having a favorable outcome at 6 months if they had resolution of clinical disease, a negative culture status, and had not already been classified as having had an unfavorable outcome. Other efficacy end points and safety were also evaluated. RESULTS: A total of 109 patients were enrolled in the study and were included in the evaluation of efficacy and safety end points. At 6 months after the end of treatment in the intention-to-treat analysis, 11 patients (10%) had an unfavorable outcome and 98 patients (90%; 95% confidence interval, 83 to 95) had a favorable outcome. The 11 unfavorable outcomes were 7 deaths (6 during treatment and 1 from an unknown cause during follow-up), 1 withdrawal of consent during treatment, 2 relapses during follow-up, and 1 loss to follow-up. The expected linezolid toxic effects of peripheral neuropathy (occurring in 81% of patients) and myelosuppression (48%), although common, were manageable, often leading to dose reductions or interruptions in treatment with linezolid. CONCLUSIONS: The combination of bedaquiline, pretomanid, and linezolid led to a favorable outcome at 6 months after the end of therapy in a high percentage of patients with highly drug-resistant forms of tuberculosis; some associated toxic effects were observed. (Funded by the TB Alliance and others; ClinicalTrials.gov number, NCT02333799.).

Bedaquiline and Delamanid in Children With XDR Tuberculosis: What is prolonged QTc?

Bedaquiline and delamanid used to treat extensively drug-resistant tuberculosis are known to cause prolonged QTc. Two children with extensively drug-resistant tuberculosis were put on bedaquiline and delamanid and had prolonged QTc on the Bazett formula but normal QTc by the Fridericia formula. Both had no adverse effects. Correct formula for monitoring QTc should be used thereby preventing unnecessary withholding of medicines.

Effect of Natural Phenolics on Pharmacokinetic Modulation of Bedaquiline in Rat to Assess the Likelihood of Potential Food-Drug Interaction.

Bedaquiline (TMC-207) is a recently approved drug for the treatment of multidrug-resistant tuberculosis (MDR-TB). Moreover, there is a present and growing concern for natural-product-mediated drug interaction, as these are inadvertently taken by patients as a dietary supplement, food additive, and medicine. In the present study, we investigated the impact of 20 plant-based natural products, typically phenolics, on in vivo oral bedaquiline pharmacokinetics, as previous studies are lacking. Three natural phenolics were identified that can significantly enhance the oral exposure of bedaquiline upon coadministration. We further investigated the possible role of all of the phytochemicals on in vitro P-glycoprotein (P-gp) induction and inhibition and CYP3A4 inhibition in a single platform as bedaquiline is the substrate for both P-gp and CYP3A4. In conclusion, curcumin, CC-I (3',5-dihydroxyflavone-7-O-ß-d-galacturonide-4'-O-ß-d-glucopyranoside), and 6-gingerol should not be coadministered with bedaquiline to avoid untoward drug interactions and, subsequently, its dose-dependent adverse effects.

Bedaquiline, moxifloxacin, pretomanid, and pyrazinamide during the first 8 weeks of treatment of patients with drug-susceptible or drug-resistant pulmonary tuberculosis: a multicentre, open-label, partially randomised, phase 2b trial.

BACKGROUND: New anti-tuberculosis regimens that are shorter, simpler, and less toxic than those that are currently available are needed as part of the global effort to address the tuberculosis epidemic. We aimed to investigate the bactericidal activity and safety profile of combinations of bedaquiline, pretomanid, moxifloxacin, and pyrazinamide in the first 8 weeks of treatment of pulmonary tuberculosis. METHODS: In this multicentre, open-label, partially randomised, phase 2b trial, we prospectively recruited patients with drug-susceptible or rifampicin-resistant pulmonary tuberculosis from seven sites in South Africa, two in Tanzania, and one in Uganda. Patients aged 18 years or older with sputum smear grade 1+ or higher were eligible for enrolment, and a molecular assay (GeneXpert or MTBDRplus) was used to confirm the diagnosis of tuberculosis and to distinguish between drug-susceptible and rifampicin-resistant tuberculosis. Patients who were HIV positive with a baseline CD4 cell count of less than 100 cells per uL were excluded. Patients with drug-susceptible tuberculosis were randomly assigned (1:1:1) using numbered treatment packs with sequential allocation by the pharmacist to receive 56 days of treatment with standard tuberculosis therapy (oral isoniazid, rifampicin, pyrazinamide, and ethambutol; HRZE), or pretomanid (oral 200 mg daily) and pyrazinamide (oral 1500 mg daily) with either oral bedaquiline 400 mg daily on days 1-14 then 200 mg three times per week (BloadPaZ) or oral bedaquiline 200 mg daily (B200PaZ). Patients with rifampicin-resistant tuberculosis received 56 days of the B200PaZ regimen plus moxifloxacin 400 mg daily (BPaMZ). All treatment groups were open label, and randomisation was not stratified. Patients, trial investigators and staff, pharmacists or dispensers, laboratory staff (with the exception of the mycobacteriology laboratory staff), sponsor staff, and applicable contract research organisations were not masked. The primary efficacy outcome was daily percentage change in time to sputum culture positivity (TTP) in liquid medium over days 0-56 in the drug-susceptible tuberculosis population, based on non-linear mixed-effects regression modelling of log10 (TTP) over time. The efficacy analysis population contained patients who received at least one dose of medication and who had efficacy data available and had no major protocol violations. The safety population contained patients who received at least one dose of medication. This study is registered with ClinicalTrials.gov, NCT02193776, and all patients have completed follow-up. FINDINGS: Between Oct 24, 2014, and Dec 15, 2015, we enrolled 180 patients with drug-susceptible tuberculosis (59 were randomly assigned to BloadPaZ, 60 to B200PaZ, and 61 to HRZE) and 60 patients with rifampicin-resistant tuberculosis. 57 patients in the BloadPaZ group, 56 in the B200PaZ group, and 59 in the HRZE group were included in the primary analysis. B200PaZ produced the highest daily percentage change in TTP (5·17% [95% Bayesian credibility interval 4·61-5·77]), followed by BloadPaZ (4·87% [4·31-5·47]) and HRZE group (4·04% [3·67-4·42]). The bactericidal activity in B200PaZ and BloadPaZ groups versus that in the HRZE group was significantly different. Higher proportions of patients in the BloadPaZ (six [10%] of 59) and B200PaZ (five [8%] of 60) groups discontinued the study drug than in the HRZE group (two [3%] of 61) because of adverse events. Liver enzyme elevations were the most common grade 3 or 4 adverse events and resulted in the withdrawal of ten patients (five [8%] in the BloadPaZ group, three [5%] in the B200PaZ group, and two [3%] in the HRZE group). Serious treatment-related adverse events affected two (3%) patients in the BloadPaZ group and one (2%) patient in the HRZE group. Seven (4%) patients with drug-susceptible tuberculosis died and four (7%) patients with rifampicin-resistant tuberculosis died. None of the deaths were considered to be related to treatment. INTERPRETATION: B200PaZ is a promising regimen to treat patients with drug-susceptible tuberculosis. The bactericidal activity of both these regimens suggests that they have the potential to shorten treatment, and the simplified dosing schedule of B200PaZ could improve treatment adherence in the field. However, these findings must be investigated further in a phase 3 trial assessing treatment outcomes. FUNDING: TB Alliance, UK Department for International Development, Bill & Melinda Gates Foundation, US Agency for International Development, Directorate General for International Cooperation of the Netherlands, Irish Aid, Australia Department of Foreign Affairs and Trade, and the Federal Ministry for Education and Research of Germany.

Progress in global rollout of new multidrug-resistant tuberculosis treatments.

SETTING: The global multidrug-resistant tuberculosis (MDR-TB) epidemic has grown over the past decade and continues to be difficult to manage. In response, new drugs and treatment regimens have been recommended.OBJECTIVE: In 2017 and again in 2018, the International Union Against Tuberculosis and Lung Disease (The Union) drug-resistant (DR) TB Working Group collaborated with RESIST-TB to implement an internet survey to members of The Union around the world to assess access to these new treatment strategies.DESIGN: A nine-question survey was developed using SurveyMonkey®. The survey was open for participation to all members of The Union registered under the TB Section. Two reminders were sent during each survey. The responses were analyzed taking into account the WHO Region to which the respondent belonged.RESULTS: The 2018 survey showed a global increase in implementation of the shorter (9-month) MDR-TB regimen (from 33% to 56% of respondents, P < 0.001) and an increase in the use of bedaquiline and/or delamanid (from 25% to 41% of respondents, P < 0.001) compared to 2017. There were substantial variations in roll-out between WHO regions.CONCLUSION: These results demonstrate improvement in global implementation of the new treatment strategies over a 1-year period.

Switching to bedaquiline for treatment of rifampicin-resistant tuberculosis in South Africa: A retrospective cohort analysis.

South Africa led the world with guidelines on bedaquiline (BDQ) use as a single drug substitution to manage rifampin resistant tuberculosis regimen toxicity. We examined reasons for giving BDQ in a retrospective cohort: >75% of patients were switched to BDQ for toxicity (ototoxicity or renal dysfunction) rather than drug resistance.

Daily Dosing for Bedaquiline in Patients with Tuberculosis.

The bedaquiline regimen for the treatment of multidrug-resistant tuberculosis (MDR-TB) in adults is a loading dose of 400 mg QD for 2 weeks followed by 200 mg thrice weekly (TIW) for 22 weeks. Most TB antibiotics administered with bedaquiline are given QD. Using pharmacokinetic simulations, we explored alternative QD bedaquiline regimens and determined that 200 mg QD for 8 weeks followed by 100 mg QD provides comparable exposures to the approved regimen. This simpler regimen is under clinical evaluation.

Development and validation of an LC-MS/MS method for the simultaneous determination of bedaquiline and rifabutin in human plasma.

This article describes the simultaneous determination of bedaquiline fumarate (TMC-207) and rifabutin in human plasma by stable isotope dilution tandem mass spectrometry. The methodology was developed for an investigation of potential drug-drug interactions of the two anti-tuberculosis drugs when given together to healthy human volunteers. Use of the two drugs in combination to treat disease caused by Mycobacterium tuberculosis is contemplated as the bacterium becomes resistant to many currently available drugs.

A safety evaluation of bedaquiline for the treatment of multi-drug resistant tuberculosis.

Introduction: Outcomes of treatment for resistant tuberculosis are poor, with long treatment duration and poor tolerability. Bedaquiline is a novel anti-mycobacterial drug, which has a very long terminal elimination half-life. Bedaquiline was approved in 2012 for drug-resistant tuberculosis following improved time to culture conversion and cure rates in a phase 2b study; but mortality was higher in the bedaquiline arm, resulting in a black box warning despite the fact that almost all deaths occurred after bedaquiline was stopped. Areas covered: The authors review safety data of bedaquiline used for rifampicin-resistant tuberculosis from the phase 2 studies, and from case series and observational cohorts. The authors focus on QT interval prolongation, hepatotoxicity, and mortality. Expert opinion: Bedaquiline markedly reduced mortality and improved treatment success in observational studies, resulting in bedaquiline being strongly recommended for rifampicin-resistant tuberculosis by the World Health Organization. In the phase 2 studies participants randomised to bedaquiline had higher rates of liver enzyme elevation and modest QT interval prolongation. Severe QT prolongation was an infrequent cause of bedaquiline interruption despite the frequent use of concomitant drugs that also prolong the QT interval. While awaiting results of phase 3 randomised controlled trials, tuberculosis treatment programmes should strengthen pharmacovigilance.

Surveillance of adverse events in the treatment of drug-resistant tuberculosis: A global feasibility study.

The World Health Organization launched a global initiative, known as aDSM (active TB drug safety monitoring and management) to better describe the safety profile of new treatment regimens for drug-resistant tuberculosis (TB) in real-world settings. However, comprehensive surveillance is difficult to implement in several countries. The aim of the aDSM project is to demonstrate the feasibility of implementing national aDSM registers and to describe the type and the frequency of adverse events (AEs) associated with exposure to the new anti-TB drugs. Following a pilot study carried out in 2016, official involvement of TB reference centres/countries into the project was sought and cases treated with bedaquiline- and/or delamanid-containing regimens were consecutively recruited. AEs were prospectively collected ensuring potential attribution of the AE to a specific drug based on its known safety profile. A total of 309 cases were fully reported from 41 centres in 27 countries (65% males; 268 treated with bedaquiline, 20 with delamanid, and 21 with both drugs) out of an estimated 781 cases the participating countries had committed to report by the first quarter of 2019.