Multidrug-resistant Tuberculosis Regimen Research Articles

Diastolic dysfunction due to bedaquiline: A case report

Abstract
 Background
 There is no published case of diastolic dysfunction arising due to bedaquiline treatment for Multi-Drug Resistant Tuberculosis (MDR-TB). Diastolic dysfunction is not listed as a potential complication of treatment with bedaquiline. This case report is the first to link bedaquiline to diastolic dysfunction. Clinicians should be aware of this potential complication, and ensure that patients are monitored and investigated appropriately.
 Case Presentation
 A 47 year old female presented with fever, productive cough and drenching night sweats for more than 2 weeks prior to presentation. There was no hemoptysis, chest pains or weight loss. She however, felt breathless after a heavy bout of coughing. Fever was intermittent, and most pronounced at night. The patient denied any weight loss over the past month. The patient had no history of HIV, diabetes, hypertension or heart disease. There were no previous episodes of TB. There was history of contact with a patient with MDR-TB patient. The patients’ son, who shared a house and all living spaces with the patient, was being treated for MDR-TB at the time of presentation. The patient did not drink or smoke. There was no history of illicit drug use. She worked as a restaurant manager. Due to the history of very close contact with MDR-TB, the patient was commenced on the longer, oral only regimen for MDR-TB which includes bedaquiline. Four weeks after commencement of bedaquiline, the patient complained that both feet were swelling. There were no other symptoms or signs of cardiovascular disease. An Echocardiogram done during the fifth month showed an ejection fraction of 71% and diastolic dysfunction. The patient was commenced on diuretics and continued on MDR-TB treatment. An echocardiogram that was repeated at month 15 review showed an ejection fraction of 64%, normal left ventricle and normal systolic and diastolic function.
 Conclusions
 Diastolic Dysfunction has not previously been reported in patients on bedaquiline. This is the first case report to link bedaquiline to diastolic dysfunction. More studies need to be done to determine conclusively whether bedaquiline can cause diastolic dysfunction.

The heme oxygenase-1 metalloporphyrin inhibitor stannsoporfin enhances the bactericidal activity of a novel regimen for multidrug-resistant tuberculosis in a murine model.

Multidrug-resistant (MDR) Mycobacterium tuberculosis (Mtb) poses significant challenges to global tuberculosis (TB) control efforts. Host-directed therapies (HDTs) offer a novel approach to TB treatment by enhancing immune-mediated clearance of Mtb. Prior preclinical studies found that the inhibition of heme oxygenase-1 (HO-1), an enzyme involved in heme metabolism, with tin-protoporphyrin IX (SnPP) significantly reduced mouse lung bacillary burden when co-administered with the first-line antitubercular regimen. Here, we evaluated the adjunctive HDT activity of a novel HO-1 inhibitor, stannsoporfin (SnMP), in combination with a novel MDR-TB regimen comprising a next-generation diarylquinoline, TBAJ-876 (S), pretomanid (Pa), and a new oxazolidinone, TBI-223 (O) (collectively, SPaO), in Mtb-infected BALB/c mice. After 4 weeks of treatment, SPaO + SnMP 5mg/kg reduced mean lung bacillary burden by an additional 0.69 log10 (P = 0.01) relative to SPaO alone. As early as 2 weeks post-treatment initiation, SnMP adjunctive therapy differentially altered the expression of pro-inflammatory cytokine genes and CD38, a marker of M1 macrophages. Next, we evaluated the sterilizing potential of SnMP adjunctive therapy in a mouse model of microbiological relapse. After 6 weeks of treatment, SPaO + SnMP 10mg/kg reduced lung bacterial burdens to 0.71 ± 0.23 log10 colony-forming units (CFUs), a 0.78 log-fold greater decrease in lung CFU compared to SpaO alone (P = 0.005). However, adjunctive SnMP did not reduce microbiological relapse rates after 5 or 6 weeks of treatment. SnMP was well tolerated and did not significantly alter gross or histological lung pathology. SnMP is a promising HDT candidate requiring further study in combination with regimens for drug-resistant TB.

Adaptive evaluation of mHealth and conventional adherence support interventions to optimize outcomes with new treatment regimens for drug-resistant tuberculosis and HIV in South Africa (ADAP-TIV): study protocol for an adaptive randomized controlled trial

BackgroundHighly effective, short-course, bedaquiline-containing treatment regimens for multidrug-resistant tuberculosis (MDR-TB) and integrase strand transfer inhibitor (INSTI)-containing fixed dose combination antiretroviral therapy (ART) have radically transformed treatment for MDR-TB and HIV. However, without advances in adherence support, we may not realize the full potential of these therapeutics. The primary objective of this study is to compare the effect of adherence support interventions on clinical and biological endpoints using an adaptive randomized platform.MethodsThis is a prospective, adaptive, randomized controlled trial comparing the effectiveness of four adherence support strategies on a composite clinical outcome in adults with MDR-TB and HIV initiating bedaquiline-containing MDR-TB treatment regimens and receiving ART in KwaZulu-Natal, South Africa. Trial arms include (1) enhanced standard of care, (2) psychosocial support, (3) mHealth using cellular-enabled electronic dose monitoring, and (4) combined mHealth and psychosocial support. The level of support will be titrated using a differentiated service delivery (DSD)-informed assessment of treatment support needs. The composite primary outcome will include survival, negative TB culture, retention in care, and undetectable HIV viral load at month 12. Secondary outcomes will include individual components of the primary outcome and quantitative evaluation of adherence on TB and HIV treatment outcomes.DiscussionThis trial will evaluate the contribution of different modes of adherence support on MDR-TB and HIV outcomes with WHO-recommended all-oral MDR-TB regimens and ART in a high-burden operational setting. We will also assess the utility of a DSD framework to pragmatically adjust levels of MDR-TB and HIV treatment support.Trial registrationClinicalTrials.gov NCT05633056. Registered on 1 December 2022

Evaluating newly approved drugs in combination regimens for multidrug-resistant tuberculosis with fluoroquinolone resistance (endTB-Q): study protocol for a multi-country randomized controlled trial

BackgroundTreatment for fluoroquinolone-resistant multidrug-resistant/rifampicin-resistant tuberculosis (pre-XDR TB) often lasts longer than treatment for less resistant strains, yields worse efficacy results, and causes substantial toxicity. The newer anti-tuberculosis drugs, bedaquiline and delamanid, and repurposed drugs clofazimine and linezolid, show great promise for combination in shorter, less-toxic, and effective regimens. To date, there has been no randomized, internally and concurrently controlled trial of a shorter, all-oral regimen comprising these newer and repurposed drugs sufficiently powered to produce results for pre-XDR TB patients.MethodsendTB-Q is a phase III, multi-country, randomized, controlled, parallel, open-label clinical trial evaluating the efficacy and safety of a treatment strategy for patients with pre-XDR TB. Study participants are randomized 2:1 to experimental or control arms, respectively. The experimental arm contains bedaquiline, linezolid, clofazimine, and delamanid. The control comprises the contemporaneous WHO standard of care for pre-XDR TB. Experimental arm duration is determined by a composite of smear microscopy and chest radiographic imaging at baseline and re-evaluated at 6 months using sputum culture results: participants with less extensive disease receive 6 months and participants with more extensive disease receive 9 months of treatment. Randomization is stratified by country and by participant extent-of-TB-disease phenotype defined according to screening/baseline characteristics. Study participation lasts up to 104 weeks post randomization. The primary objective is to assess whether the efficacy of experimental regimens at 73 weeks is non-inferior to that of the control. A sample size of 324 participants across 2 arms affords at least 80% power to show the non-inferiority, with a one-sided alpha of 0.025 and a non-inferiority margin of 12%, against the control in both modified intention-to-treat and per-protocol populations.DiscussionThis internally controlled study of shortened treatment for pre-XDR TB will provide urgently needed data and evidence for clinical and policy decision-making around the treatment of pre-XDR TB with a four-drug, all-oral, shortened regimen.Trial registrationClinicalTrials.Gov NCT03896685. Registered on 1 April 2018; the record was last updated for study protocol version 4.3 on 17 March 2023.

Study protocol for safety and efficacy of all-oral shortened regimens for multidrug-resistant tuberculosis: a multicenter randomized withdrawal trial and a single-arm trial [SEAL-MDR

IntroductionThe urgent need for new treatments for multidrug-resistant tuberculosis (MDR-TB) and pre-extensively drug-resistant tuberculosis (pre-XDR-TB) is evident. However, the classic randomized controlled trial (RCT) approach faces ethical and practical constraints, making alternative research designs and treatment strategies necessary, such as single-arm trials and host-directed therapies (HDTs).MethodsOur study adopts a randomized withdrawal trial design for MDR-TB to maximize resource allocation and better mimic real-world conditions. Patients’ treatment regimens are initially based on drug resistance profiles and patient’s preference, and later, treatment-responsive cases are randomized to different treatment durations. Alongside, a single-arm trial is being conducted to evaluate the potential of sulfasalazine (SASP) as an HDT for pre-XDR-TB, as well as another short-course regimen without HDT for pre-XDR-TB. Both approaches account for the limitations in second-line anti-TB drug resistance testing in various regions.DiscussionAlthough our study designs may lack the internal validity commonly associated with RCTs, they offer advantages in external validity, feasibility, and ethical appropriateness. These designs align with real-world clinical settings and also open doors for exploring alternative treatments like SASP for tackling drug-resistant TB forms. Ultimately, our research aims to strike a balance between scientific rigor and practical utility, offering valuable insights into treating MDR-TB and pre-XDR-TB in a challenging global health landscape. In summary, our study employs innovative trial designs and treatment strategies to address the complexities of treating drug-resistant TB, fulfilling a critical gap between ideal clinical trials and the reality of constrained resources and ethical considerations.Trail registrationChictr.org.cn, ChiCTR2100045930. Registered on April 29, 2021.

Cost of digital technologies and family-observed DOT for a shorter MDR-TB regimen: a modelling study in Ethiopia, India and Uganda

BackgroundIn 2017, the WHO recommended the use of digital technologies, such as medication monitors and video observed treatment (VOT), for directly observed treatment (DOT) of drug-susceptible TB. The WHO’s 2020 guidelines extended these recommendations to multidrug-resistant tuberculosis (MDR-TB), based on low evidence. The impact of COVID on health systems and patients underscored the need to use digital technologies in the management of MDR-TB.MethodsA decision-tree model was developed to explore the costs of several potential DOT alternatives: VOT, 99DOTS (Directly-observed Treatment, Short-course) and family-observed DOT. Assuming a 9-month, all-oral regimen (as evaluated within the STREAM trial), we constructed base-case cost models for the standard-of-care DOTs in Ethiopia, India, and Uganda, as well as for the three alternative DOT approaches. The models were populated with STREAM Stage 2 clinical trial outcome and cost data, supplemented with market prices data for the digital DOT strategies. Sensitivity analyses were conducted on key parameters.ResultsModelling suggested that the standard-of-care DOT approach is the most expensive DOT strategy from a societal perspective in all three countries evaluated (Ethiopia, India, Uganda), with considerable direct- and indirect-costs incurred by patients. The second most expensive DOT approach is VOT, with high health-system costs, largely caused by up-front technology expenditure.Each of VOT, 99DOTS and family-observed DOT would reduce by more than 90% patients’ direct and indirect costs compared to standard of care DOT.Results were robust to the sensitivity analyses.ConclusionsWhile data on the costs and efficacy of alternative DOT approaches in the context of shorter MDR-TB treatment is limited, our modelling suggests alternative DOT approaches can significantly reduce patient costs in all three countries. Health system costs are higher for VOT and lower for 99DOTS and family-observed therapy when compared to standard of care DOT, as low smartphone penetration and internet availability requires the VOT health system to fund the cost of making them available to patients.

Meropenem-vaborbactam restoration of first-line drug efficacy and comparison of meropenem-vaborbactam-moxifloxacin versus BPaL MDR-TB regimen

Meropenem in combination with β-lactamase inhibitors (BLIs) and other drugs was tested to identify alternative treatment regimens for multidrug-resistant tuberculosis (MDR-TB). The following were performed: (1) MIC experiments; (2) static time-kill studies (STKs) with different BLIs; and (3) a hollow fibre model system of TB (HFS-TB) studies with meropenem-vaborbactam combined with human equivalent daily doses of 20 mg/kg or 35 mg/kg rifampin, or moxifloxacin 400 mg, or linezolid 600 mg vs. bedaquiline-pretonamid-linezolid (BPaL) for MDR-TB. The studies were performed using Mycobacterium tuberculosis (M. tuberculosis) H37Rv and an MDR-TB clinical strain (named M. tuberculosis 16D) that underwent whole genome sequencing. Exponential decline models were used to calculate the kill rate constant (K) of different HFS-TB regimens. Whole genome sequencing revealed mutations associated with resistance to rifampin, isoniazid, and cephalosporins. The meropenem-vaborbactam MIC of M. tuberculosis was H37Rv 2mg/L and > 128 mg/L for M. tuberculosis 16D. Relebactam and vaborbactam improved both the potency and efficacy of meropenem in STKs. Meropenem-vaborbactam alone failed to kill M. tuberculosis 16D but killed below day 0 burden when combined with isoniazid and rifampin, with the moxifloxacin combination being the most effective and outranking bedaquiline and pretomanid. In the HFS-TB, meropenem-vaborbactam-moxifloxacin and BPaL had the highest K (log10 cfu/mL/day) of 0.31 (95% CI 0.17-0.58) and 0.34 (95% CI 0.21-0.56), while meropenem-vaborbactam-rifampin (35 mg/kg) had a K of 0.18 (95% CI 0.12-0.25). The K for meropenem-vaborbactam-moxifloxacin-linezolid demonstrated antagonism. Adding meropenem-vaborbactam could potentially restore the efficacy of isoniazid and rifampin against MDR-TB. The meropenem-vaborbactam-moxifloxacin backbone regimen has implications for creating a new effective MDR-TB regimen.

Shorter Oral Regimen for Multidrug Resistant Tuberculosis in South Korea

The treatment of multidrug- and rifampin-resistant tuberculosis (MDR/RR-TB) poses significant challenges, including frequent adverse drug reactions associated with complex treatment regimens involving multiple drugs administered over prolonged periods. However, recent clinical trials, such as Nix-TB, ZeNix, NExT, MDR-END, TB-PRACTECAL, and BEAT-India, have demonstrated that shorter oral regimens yield superior outcomes compared with conventional approaches. Furthermore, the World Health Organization guidelines for MDR/RR-TB treatment recommend a 6-month all-oral regimen that includes bedaquiline, pretomanid, linezolid, and moxifloxacin. However, the implementation of these shorter oral regimens in South Korea requires careful consideration. Health insurance coverage policies must be reviewed to include new TB drugs, such as pretomanid. The optimal dosage and treatment duration of linezolid should be determined to minimize side effects and prevent drug resistance; moreover, alternative regimens should be identified for patients who discontinue linezolid because of adverse drug reactions.

Isoniazid resistance-conferring mutations are associated with highly variable phenotypic resistance

BackgroundHigh-dose isoniazid is recommended in the 9–12 months short-course regimen for multidrug-resistant tuberculosis with inhA mutation. However, there is insufficient evidence to support the assumption of genotypic-phenotypic concordance. This study aimed to identify the genetic mutations associated with high-level phenotypic isoniazid resistance. MethodsClinical isolates from patients with drug-resistant tuberculosis were profiled by whole-genome sequencing and subjected to minimum inhibitory concentration (MIC) testing using MGIT based-method. MICs were performed in concentration ranges based on the mutation present: isolates with no isoniazid resistance-conferring mutations and H37Rv, 0.016–0.256 µg/ml; inhA, 0.256–4.0 µg/ml, katG 1.0–16.0 µg/ml; and inhA + katG, 4.0–64.0 µg/ml. Isolates demonstrating resistance at the upper limit of the concentration range were tested up to the maximum of 64.0 µg/ml. Bootstrap of the mean MICs was performed to increase the robustness of the estimates and an overlap index was used to compare the distributions of the MICs for each mutation profile. ResultsA total of 52 clinical isolates were included in this analysis. Bootstrap MIC means for inhA, katG and inhA + katG were 33.64 (95% CI, 9.47, 56.90), 6.79 (4.45, 9.70) and 52.34 (42.750, 61.66) µg/ml, respectively. There was high overlap between inhA and inhA + katG mutations (eta = 0.45) but not with inhA and katG (eta = 0.19). Furthermore, katG showed poor overlap with inhA + katG mutations (eta = 0.09). Unexpectedly, 4/8 (50.0%) of all InhA mutants demonstrated high-level resistance, while 20/24 (83.3%) of katG mutants demonstrated moderate-level resistance. ConclusionsInhA mutations demonstrated unexpectedly high MICs and showed high overlap with inhA + katG. Contrary to the common belief that katG mutants are associated with high-level resistance, this mutation primarily showed moderate-level resistance.

Comparing adherence to MDR-TB treatment among patients on self-administered therapy and those on directly observed therapy: non-inferiority randomized controlled trial

BackgroundAdherence is key to the treatment success of multi-drug resistant tuberculosis (MDR-TB) and prevention of community transmission. Directly observed therapy (DOT) is the recommended approach for the management of patients with MDR-TB. Uganda implements a health facility-based DOT approach where all patients diagnosed with MDR-TB report to the nearest private or public health facility for daily observation of ingesting their medicines by a health care provider. Directly observed therapy is very costly for both the patient and health care system. It follows the assumption that MDR TB patients have a history of poor adherence to TB treatment. But only 21% of MDR-TB patients notified globally and 1.4–12% notified in Uganda had been previously treated for TB. The shift to all oral treatment regimen for MDR-TB provides an opportunity for the exploration of self-administered therapy for this group of patients even with use of remotely operated adherence technology. We are conducting a non-inferiority open-label randomized controlled trial to compare adherence to MDR-TB treatment among patients on self-administered therapy (measured by Medication Events Monitoring System (MEMS) technology) with a control group on DOT.MethodsWe plan to enrol 164 newly diagnosed MDR-TB patients aged ≥ 8 years from three regional hospitals based in rural and urban Uganda. Patients with conditions that affect their dexterity and ability to operate the MEMS-operated medicine equipment will not be eligible to participate in the trial. Patients are randomized to either of the two study arms: self-administered therapy with adherence being monitored using MEMS technology (intervention arm) or health facility-based DOT (control arm) and will be followed up monthly. Adherence is measured by the number of days the medicine bottle is open to access medication as recorded by the MEMS software in the intervention arm and treatment complaint days as recorded in the TB treatment card in the control arm. The primary outcome is the comparison of adherence rates between the two study arms.DiscussionThe evaluation of self-administered therapy for patients with MDR-TB is important to inform cost-effective management strategies for these patients. The approval of all oral regimens for the treatment of MDR-TB provides an opportunity for innovations such as MEMS technology to support sustainable options for MDR-TB treatment adherence support in low-resource settings.Trial registrationPan African Clinical Trials Registry, Cochrane #PACTR202205876377808. Retrospectively registered on 13 May 2022

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

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.

At Long Last: Short, All-Oral Regimens for Multidrug-Resistant Tuberculosis in the United States.

Multidrug-resistant tuberculosis (MDR-TB) has historically required longer treatment regimens that were associated with higher unfavorable outcomes and side effects rates compared with drug susceptible TB (DS-TB). During the last decade, several studies conducted mostly in high-incidence settings have shown that MDR-TB can be successfully treated using all-oral shorter regimens of 6- to 9-month duration. In this article, we review the evolution of MDR-TB treatment from the early long regimens with injectables agents (IAs), followed by the shorter regimens with IA, to the groundbreaking, all-oral, 6- to 9-month regimens. Finally, we propose a framework for implementation of the shorter all-oral regimens in the United States.

Management of drug resistant tuberculosis: isoniazid resistant, rifampicin resistant, multi drug resistant, and extensively drug resistant

Mycobacterium tuberculosis strains that are resistant to an elevating number of second-line medicines used to treat multidrug-resistant tuberculosis are becoming a threat to public health worldwide. Recent guidelines recommended at least 20 months of treatment, but recent regimens are toxic, poorly tolerated and insufficiently effective, with cure rates as low as 36% and failure rates as high as 50%. The emergence of multidrug-resistant tuberculosis can be defined as strains resistant to at least isoniazid and rifampin has introduced as they are challenging, but overcome the complexities to tuberculosis programs that have responded by treating multidrug-resistant tuberculosis with second-line drugs. Longer multidrug-resistant tuberculosis regimens are treatments for rifampicin resistant tuberculosis or multidrug-resistant tuberculosis which last 18 months or more according to the new 2019 updated World Health Organization drug-resistant tuberculosis guidelines and which may be standardized or individualized. Longer multidrug-resistant tuberculosis regimens are usually designed to involve a minimum number of second-line tuberculosis medicines considered to be effective based on patient history or drug-resistance patterns. The exact number of drugs used to treat extensively tuberculosis drug-resistant is unknown, but most individuals will receive five to six drugs. Identically, as the majority of patients with extensively tuberculosis drug-resistant have been previously treated for multidrug-resistant tuberculosis, prior exposure to drugs like ethionamide and terizidone frequently excludes their use.

Internalized and Perceived Stigma and Depression in Pulmonary Tuberculosis: Do They Explain the Relationship Between Drug Sensitivity Status and Adherence?

BackgroundAdherence to medication for tuberculosis (TB) has been found to be deleteriously affected by psychosocial issues, including internalized and perceived stigma (IPS) and depression, usually resulting in the emergence of multidrug-resistant TB (MDR-TB). The objective of the study was to find the prevalence of depression among patients receiving treatment for pulmonary TB, and how stigma and depression affect the relationship between drug sensitivity status (DSS) and treatment adherence.MethodIt was a cross-sectional observational study conducted between January 2019 and July 2020 in two centers in Sikkim, India. The Patient Health Questionnaire-9 (PHQ-9), Internalized Social Stigma Scale (ISSS), and Tuberculosis Medication Adherence Scale were used to assess depression, IPS, and medication adherence, respectively. A path analysis was performed with DSS, treatment adherence, IPS, and depression. Education in years was included in the model as it was significantly correlated with IPS.ResultsA total of 71 patients who were on drug-sensitive TB (DS-TB) regimen (n = 26) and MDR-TB regimen (n = 45) participated in the study. Notably, 56.3% (n = 40) of the participants were found to have depression. Among the depressed participants, 32.5% were on the DS-TB regimen and 67.5% were on the MDR-TB regimen. The path analysis indicated that IPS and depression were serially mediating the relationship between DSS and treatment adherence (β = −0.06, p < 0.05, 95% CI = −3.20, −0.02). Finally, years of education had an exogenous predictor role, not only directly affecting IPS (β = −0.38, p < 0.001, 95% CI = −0.99, −0.31) but also affecting treatment adherence through IPS and depression (β = 0.08, p = 0.02, 95% CI = 0.03, 0.47). This indicated that with more years of education, the IPS decreases, which decreases depression and ultimately leads to better adherence.ConclusionWe found an important relationship between different psychosocial factors which may affect treatment adherence. Patients who have higher IPS are more likely to develop depression which negatively affect adherence. Patients on the MDR-TB regimen have higher stigma. There is an urgent need to integrate mental health services with TB Control Programs.

Implementation of the ‘Removed Injectable modified Short-course regimens for EXpert Multidrug Resistant Tuberculosis’ (RISE study) in Tanzania: a protocol for a mixed-methods process evaluation

IntroductionTanzania is adapting a shortened injectable-free multidrug resistant tuberculosis (MDR-TB) regimen, comprising new drugs such as bedaquiline and delamanid and repurposed drugs such as clofazimine and linezolid. The regimen is...

Prospects of contezolid (MRX-I) against multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis.

Tuberculosis has become a great global public health threat. Compared with drug-susceptible tuberculosis (TB), the treatment regimens for multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) involve more severe adverse events and poorer treatment outcomes. Linezolid (LZD) is the first oxazolidinones used for TB. Thanks to its potent activity against Mycobacterium tuberculosis, LZD has become one of the key agents in the regimens against MDR/XDR-TB. However, this drug may cause intolerability and other adverse events. Contezolid, another novel oxazolidinone, can also inhibit M. tuberculosis, still with fewer adverse effects compared with LZD. This paper is to prospect the potentials of contezolid in the treatment of MDR/XDR-TB, with focus on its efficacy and possible adverse effects.

Multidrug-resistant Tuberculosis and COVID-19 Coinfection with Diabetes Mellitus in Medan, Indonesia: A Case Report

BACKGROUND: Coronavirus disease 2019 (COVID-19) has distracted the global health system due to significant morbidity and mortality. There are increasing mortality rates related to the existence of comorbidities. Due to immunologic conditions, other infectious diseases, such as multidrug-resistant tuberculosis (MDR-TB), might coinfect with COVID-19. We describe a case of MDR-TB with diabetes mellitus and critical COVID-19 patient with fatal outcome. CASE REPORT: A 60-year-old man was admitted to our hospital with shortness of breath for 2 days. A history of recurrent shortness of breath has had developed for about 7 months. Room air oxygen saturation was at 66%. RT-PCR SARS-CoV-2 nasopharynx swab result was positive. The chest X-ray series result showed destroyed left lung with increasing infiltrate in the lower right lung. The patient was diagnosed with pulmonary MDR-TB based on GeneXpert and LPA (Line Probe Assay) test 6 months prior and also has had history of diabetes mellitus for 7 years. Then, the patient was diagnosed with COVID-19, pulmonary MDR-TB, and diabetes mellitus. MDR-TB regimen, anti-diabetic medication, and management of COVID-19 were carried out. On the 6th day, the patient’s condition worsened to the point, where he needed intubation. The patient eventually passed away. CONCLUSION: The treatment outcome was highly related to the severity of COVID-19 symptoms and complications of comorbidities when patients are admitted to the hospital. The early screening and treatment of COVID-19 are important to prevent deteriorating clinical conditions caused by comorbidities.

An All-Oral 6-Month Regimen for Multidrug-Resistant Tuberculosis: A Multicenter, Randomized Controlled Clinical Trial (the NExT Study).

Rationale: Improving treatment outcomes while reducing drug toxicity and shortening the treatment duration to ∼6 months remains an aspirational goal for the treatment of multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB). Objectives: To conduct a multicenter randomized controlled trial in adults with MDR/RR-TB (i.e., without resistance to fluoroquinolones or aminoglycosides). Methods: Participants were randomly assigned (1:1 ratio) to a ∼6-month all-oral regimen that included levofloxacin, bedaquiline, and linezolid, or the standard-of-care (SOC) ⩾9-month World Health Organization (WHO)-approved injectable-based regimen. The primary endpoint was a favorable WHO-defined treatment outcome (which mandates that prespecified drug substitution is counted as an unfavorable outcome) 24 months after treatment initiation. The trial was stopped prematurely when bedaquiline-based therapy became the standard of care in South Africa. Measurements and Main Results: In total, 93 of 111 randomized participants (44 in the comparator arm and 49 in the interventional arm) were included in the modified intention-to-treat analysis; 51 (55%) were HIV coinfected (median CD4 count, 158 cells/ml). Participants in the intervention arm were 2.2 times more likely to experience a favorable 24-month outcome than participants in the SOC arm (51% [25 of 49] vs. 22.7% [10 of 44]; risk ratio, 2.2 [1.2-4.1]; P = 0.006). Toxicity-related drug substitution occurred more frequently in the SOC arm (65.9% [29 of 44] vs. 34.7% [17 of 49]; P = 0.001)], 82.8% (24 of 29) owing to kanamycin (mainly hearing loss; replaced by bedaquiline) in the SOC arm, and 64.7% (11 of 17) owing to linezolid (mainly anemia) in the interventional arm. Adverse event-related treatment discontinuation in the safety population was more common in the SOC arm (56.4% [31 of 55] vs. 32.1% [17 of 56]; P = 0.007). However, grade 3 adverse events were more common in the interventional arm (55.4% [31 of 56] vs. 32.7 [18 of 55]; P = 0.022). Culture conversion was significantly better in the intervention arm (hazard ratio, 2.6 [1.4-4.9]; P = 0.003) after censoring those with bedaquiline replacement in the SOC arm (and this pattern remained consistent after censoring for drug replacement in both arms; P = 0.01). Conclusions: Compared with traditional injectable-containing regimens, an all-oral 6-month levofloxacin, bedaquiline, and linezolid-containing MDR/RR-TB regimen was associated with a significantly improved 24-month WHO-defined treatment outcome (predominantly owing to toxicity-related drug substitution). However, drug toxicity occurred frequently in both arms. These findings inform strategies to develop future regimens for MDR/RR-TB.Clinical trial registered with www.clinicaltrials.gov (NCT02454205).

Effectiveness and Safety of Short-term Regimen for Multidrug-resistant Tuberculosis Treatment: A Systematic Review of Cohort Studies.

This systematic review explores the effectiveness and safety of a short-term regimen (STR) in treating multidrug-resistant tuberculosis (MDR-TB). We use several cohort studies which were searched using standardized Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The keywords were used based on problem, intervention, comparison, and outcome consisted of MDR-TB and STR. Seven cohort studies were selected from 314 studies. The result showed that STR has better therapeutic efficacy and shorter duration than the 2011 World Health Organization regimen for MDR-TB with success rates above 50% in respective studies. The most effective regimen was kanamycin-high-dose isoniazid-clofazimine-ethambutol-prothionamide-pyrazinamide-gatifloxacin in the intensive phase for four months and clofazimine-ethambutol-pyrazinamide-gatifloxacin-prothionamide in the continuation phase for eight months. Gastrointestinal problems, ototoxicity, dysglycemia, and liver problems were the most reported side effects. STR provides good effectiveness in MDR-TB treatment in terms of treatment success rate and short therapy duration.

Effectiveness and Safety of 9-Month Treatment Regimen for Multidrug-Resistant Tuberculosis in the Philippines

Background: The Philippines has a burden of drug-resistant tuberculosis (DR-TB). One of the key challenges in the programmatic management of DR-TB (PMDT) is the high rate of loss to follow-up (38% in the 2010 cohort). An urgent need for a shorter, more tolerable, less expensive treatment regimen exists. The aim of the operational study is to determine the efficacy and safety of the short treatment regimen among drug resistant TB. Methods: This is a prospective single-arm cohort study evaluating the effectiveness and safety of a shorter 9 - 11-month treatment regimen (9MTR) for rifampicin-resistant/multi-drug resistant TB (RR/MDR-TB) in 10 PMDT facilities. All eligible consenting adult patients with rifampicin-resistant TB were enrolled and received the standardized 9-month treatment regimen (9MTR), including injectables, with a follow-up after 12 months of treatment completion. Results: A total of 329 patients were enrolled from July 2015 to December 2016. At the 6th month post-enrollment, 256 (77.8%) of them had culture-negative test results. The end-of-treatment success rate was 74.1% (224 [68.0%] were cured and 20 [6.1%] completed the treatment). On the other hand, 10 (3.0%) died, 41 (12.5%) lost to follow-up, 33 (10.0%) withdrawn, 1 (0.3%) treatment failure. In the 12th month after 9MTR completion, among the 244 patients with successful treatment, 198 (81.1%) had culture-negative results, while there were 46 patients whose culture tests were not done. One patient developed TB relapse with fluoroquinolone resistance. The majority of the adverse events were mild that occurred mostly during the first 6 months of treatment. Conclusion: The 9-month treatment regimen had a high treatment success rate with a favorable safety profile. The loss to follow-up was reduced; however, it was still a challenge. The introduction of the 9MTR via operational research had a major impact on building national capacity and infrastructure for the programmatic adoption of a new regimen. Ten PMDT centers received training and experience, created diagnostic pathways, and active drug safety monitoring and management were built.