Interim Effectiveness and Safety Comparison of Bedaquiline-Containing Regimens for Treatment of Diabetic Versus Non-Diabetic MDR/XDR-TB Patients in China: A Multicenter Retrospective Cohort Study

Predictors of early and interim culture un-conversion in multidrug-resistant/rifampicin-resistant tuberculosis: a retrospective multi-center cohort study in China

BACKGROUND

We aimed to evaluate the predictors for early and interim culture conversion within 2 months and 6 months of treatment in multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) patients in China.

METHODS

This study included adult MDR/RR-TB patients with a positive baseline sputum culture from 8 institutions located in different cities in China from May 2018 to January 2022. We mainly used logistic regression model to derive possible predictors of early and interim culture conversion.

RESULTS

A total of 813 patients were enrolled and 28.5% of them received multidrug-resistant treatment regimens containing bedaquiline. Of these, 362 (44.5%) patients experienced culture conversion within 2 months of treatment, and 649 (79.8%) within 6 months. The results of the multivariable logistic regression analysis revealed that acid-fast bacilli smear positive (adjusted odds ratio [aOR] = 1.637, 95% confidence interval [CI] = 1.197-2.238), cavities (aOR = 1.539, 95% CI = 1.132-2.092), bilateral disease (aOR = 1.638, 95% CI = 1.183-2.269), and viral hepatitis (aOR = 2.585, 95% CI = 1.189-5.622) were identified as risk factors for early culture un-conversion within 2 months of treatment. Additionally, smoking history (aOR = 2.197, 95% CI = 1.475-3.273), previous treatment for tuberculosis (aOR = 1.909, 95% CI = 1.282-2.844), bilateral disease (aOR = 2.201, 95% CI = 1.369-3.537), viral hepatitis (aOR = 2.329, 95% CI = 1.094-4.962) were identified as risk factors for interim culture un-conversion within 6 months of treatment, while patients with regimen containing bedaquiline (aOR = 0.310, 95% CI = 0.191-0.502) was a protective factor.

CONCLUSIONS

A history of smoking, a baseline sputum AFB smear positive, lung cavities, bilateral disease, previous anti-tuberculosis treatment, or a comorbidity of viral hepatitis can be used as the predictors for early and interim culture un-conversion in MDR/RR-TB patients, while bedaquiline was a protective factor .

New synergistic benzoquinone scaffolds as inhibitors of mycobacterial cytochrome bc1 complex to treat multi-drug resistant tuberculosis

Through a comprehensive molecular docking study, a unique series of naphthoquinones clubbed azetidinone scaffolds was arrived with promising binding affinity to Mycobacterial Cytbc1 complex, a drug target chosen to kill multi-drug resistant Mycobacterium tuberculosis (MDR-Mtb). Five compounds from series-2, 2a, 2c, 2g, 2h, and 2j, showcased significant in vitro anti-tubercular activities against Mtb H37Rv and MDR clinical isolates. Further, synergistic studies of these compounds in combination with INH and RIF revealed a potent bactericidal effect of compound 2a at concentration of 0.39 μg/mL, and remaining (2c, 2g, 2h, and 2j) at 0.78 μg/mL. Exploration into the mechanism study through chemo-stress assay and proteome profiling uncovered the down-regulation of key proteins of electron-transport chain and Cytbc1 inhibition pathway. Metabolomics corroborated these proteome findings, and heightened further understanding of the underlying mechanism. Notably, in vitro and in vivo animal toxicity studies demonstrated minimal toxicity, thus underscoring the potential of these compounds as promising anti-TB agents in combination with RIF and INH. These active compounds adhered to Lipinski's Rule of Five, indicating the suitability of these compounds for drug development. Particular significance of molecules NQ02, 2a, and 2h, which have been patented (Published 202141033473).

Effectiveness and safety of regimen containing bedaquiline and delamanid in patients with drug-resistant tuberculosis

Background

Bedaquiline and delamanid have been included in the individualized treatment regimen (ITR) to treat patients with drug-resistant tuberculosis (DR-TB).

Objective

The objective of this study is to compare the effectiveness of sputum culture conversion and the safety of ITR containing bedaquiline and delamanid.

Methods

Data were collected retrospectively from medical records of DR-TB patients who received ITR between January 2020 and December 2021. Patients were divided into bedaquiline and bedaquiline-delamanid groups. Sputum culture was evaluated until 6 months of treatment. Measurement of QTc interval, renal and liver function test, and serum potassium were evaluated to assess safety during the study period. We used Chi-square to analyze a difference in cumulative culture conversion; meanwhile, Wilcoxon and Mann-Whitney tests were used to analyze differences in laboratory data for each and between the two groups, respectively.

Results

Fifty-one eligible DR-TB patients met the inclusion criteria, 41 in the bedaquiline and 10 in bedaquiline-delamanid group. 43/51 patients had a positive culture at baseline. After 6 months of treatment, 42/43 DR-TB patients (97.6%) had sputum culture conversion and no difference between the two groups (P ≥ 0.05). QTc interval within normal limit and no patient had a QTc >500 ms during the study period. Creatinine levels significantly differed between the two groups 6 months after treatment (P < 0.05).

Conclusion

DR-TB patients who received all oral ITR containing bedaquiline and or delamanid demonstrated favorable sputum conversion with a tolerable safety profile.

Efficacy and safety of bedaquiline containing regimens in patients of drug-resistant tuberculosis: An updated systematic review and meta-analysis

BACKGROUND

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis and leads to serious complications if left untreated. Some strains of Mycobacterium tuberculosis are multi-drug resistant and require treatment with newer drugs. Bedaquiline based treatment regimens have been used in patients who are diagnosed with drug resistant tuberculosis. The aim of this study is to assess the efficacy and safety profile of bedaquiline-based treatment regimens using a systematic review of existing literature and meta-analysis.

METHODS

In this study, an electronic search was carried out on PubMed, ScienceDirect, and Cochrane library to find relevant literature from March 2021 onwards. Random-effects model was used to assess pooled treatment success rate and 95 % CIs. p-value of <0.05 was suggestive of publication bias. The review is registered with PROSPERO: CRD42023432748.

RESULTS

A total of 543 articles were retrieved by database searching, out of which 12 new studies met the inclusion criteria. The total number of articles included in the review was 41 including 36 observational studies (having a total of 9,934 patients) and 5 experimental studies (having a total of 468 patients). The pooled treatment success rate was 76.9 % (95 % CI, 72.9-80.4) in the observational studies and 81.7 % (95 % CI, 67.2-90.7) in the experimental studies. Further subgroup analysis was done on the basis of treatment regimens containing bedaquiline only and treatment regimens containing bedaquiline and delamanid. The pooled treatment success rate in the studies consisting of patients who were treated with regimens containing bedaquiline only was 78.4 % (95 % CI, 74.2-82.1) and 73.6 % (95 % CI, 64.6-81.0) in studies consisting of patients who were treated with regimens containing bedaquiline and delamanid. There was no evidence of publication bias.

CONCLUSIONS

In patients of drug resistant tuberculosis having highly resistant strains of Mycobacterium tuberculosis undergoing treatment with bedaquiline-based regimen demonstrate high rates of culture conversion and treatment success. Moreover, the safety profile of bedaquiline-based regimens is well-established in all studies.

Molecular mechanisms of resistance and treatment efficacy of clofazimine and bedaquiline against Mycobacterium tuberculosis

Clofazimine (CFZ) and bedaquiline (BDQ) are currently used for the treatment of multidrug-resistant (MDR) Mycobacterium tuberculosis (Mtb) strains. In recent years, adding CFZ and BDQ to tuberculosis (TB) drug regimens against MDR Mtb strains has significantly improved treatment results, but these improvements are threatened by the emergence of MDR and extensively drug-resistant (XDR) Mtb strains. Recently, CFZ and BDQ have attracted much attention for their strong clinical efficacy, although very little is known about the mechanisms of action, drug susceptibility test (DST), resistance mechanisms, cross-resistance, and pharmacokinetics of these two drugs. In this current review, we provide recent updates on the mechanisms of action, DST, associated mutations with individual resistance and cross-resistance, clinical efficacy, and pharmacokinetics of CFZ and BDQ against Mtb strains. Presently, known mechanisms of resistance for CFZ and/or BDQ include mutations within the Rv0678, pepQ, Rv1979c, and atpE genes. The cross-resistance between CFZ and BDQ may reduce available MDR-/XDR-TB treatment options. The use of CFZ and BDQ for treatment in the setting of limited DST could allow further spread of drug resistance. The DST and resistance knowledge are urgently needed where CFZ and BDQ resistance do emerge. Therefore, an in-depth understanding of clinical efficacy, DST, cross-resistance, and pharmacokinetics for CFZ and BDQ against Mtb can provide new ideas for improving treatment outcomes, reducing mortality, preventing drug resistance, and TB transmission. Along with this, it will also help to develop rapid molecular diagnostic tools as well as novel therapeutic drugs for TB.

Diabetes mellitus affects the treatment outcomes of drug-resistant tuberculosis: a systematic review and meta-analysis

BACKGROUND

Both tuberculosis (TB) and diabetes mellitus (DM) are major public health problems threatening global health. TB patients with DM have a higher bacterial burden and affect the absorption and metabolism for anti-TB drugs. Drug-resistant TB (DR-TB) with DM make control TB more difficult.

METHODS

This study was completed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. We searched PubMed, Excerpta Medica Database (EMBASE), Web of Science, ScienceDirect and Cochrance Library for literature published in English until July 2022. Papers were limited to those reporting the association between DM and treatment outcomes among DR-TB and multidrug-resistant TB (MDR-TB) patients. The strength of association was presented as odds ratios (ORs) and their 95% confidence intervals (CIs) using the fixed-effects or random-effects models. This study was registered with PROSPERO, number CRD: 42,022,350,214.

RESULTS

A total of twenty-five studies involving 16,905 DR-TB participants were included in the meta-analysis, of which 10,124 (59.89%) participants were MDR-TB patients, and 1,952 (11.54%) had DM history. In DR-TB patients, the pooled OR was 1.56 (95% CI: 1.24-1.96) for unsuccessful outcomes, 0.64 (95% CI: 0.44-0.94) for cured treatment outcomes, 0.63 (95% CI: 0.46-0.86) for completed treatment outcomes, and 1.28 (95% CI: 1.03-1.58) for treatment failure. Among MDR-TB patients, the pooled OR was 1.57 (95% CI: 1.20-2.04) for unsuccessful treatment outcomes, 0.55 (95% CI: 0.35-0.87) for cured treatment outcomes, 0.66 (95% CI: 0.46-0.93) for treatment completed treatment outcomes and 1.37 (95% CI: 1.08-1.75) for treatment failure.

CONCLUSION

DM is a risk factor for adverse outcomes of DR-TB or MDR-TB patients. Controlling hyperglycemia may contribute to the favorite prognosis of TB. Our findings support the importance for diagnosing DM in DR-TB /MDR-TB, and it is needed to control glucose and therapeutic monitoring during the treatment of DR-TB /MDR-TB patients.

A critical review of risk factors influencing the prevalence of extensive drug-resistant tuberculosis in India

Globally, extensive drug-resistant tuberculosis (XDR-TB) is a major element to cause morbidity and death among tuberculosis patients. The present study identifies the vital risk variables contributing to XDR-TB prevalence in India. Scopus, PubMed/Medline, Science Direct, and Google Scholar databases were searched thoroughly for the articles, using medical subject heading as a key term published between the years 2012 and 2022. According to the inclusion criteria, 11 publications were selected. Socioeconomic characteristics include employment, educational attainment, undernourishment, and the rest, and demographic factors such as gender, age, and more. Were examined in the review, whereas alcoholics, smoking, and diabetes mellitus were investigated under comorbidities and behavioral risk factors. We observed that noncompliance, poor knowledge, and insufficient health-care facilities could significantly accelerate the spread of XDR-TB, and the present review imparts a remarkable and detailed evaluation of XDR-TB. The study analysis is markedly useful for policymakers as well as researchers to discover and implement effective solutions for tuberculosis-infected patients.

The differences in drug resistance between drug-resistant tuberculosis patients with and without diabetes mellitus in northeast China: a retrospective study

BACKGROUND

Diabetes mellitus (DM) and drug-resistant tuberculosis (DR-TB) are serious global public health problems. This study aimed to explore the differences in drug resistance between DR-TB patients with and without DM. Risk factors for developing multidrug-resistant tuberculosis (MDR-TB) were also investigated among DR-TB patients.

METHODS

The patient's basic demographic,　clinical characteristics, and drug susceptibility testing (DST) data were collected from the Chinese Disease Control Information System. Descriptive statistics were used to estimate the frequency and proportion of included variables. Categorical variables were compared using the Chi-square test or Fisher's exact test. Chi-square tests for trends were used to determine changes and trends in MDR-TB and pre-extensively drug-resistantTB (pre-XDR-TB) patterns over time. Univariate and multivariate logistic regression analysis was used to explore the risk factors of MDR-TB.

RESULTS

Compared with DR-TB patients with DM, DR-TB patients without DM had significantly higher rates of mono-resistant streptomycin (SM) and any resistance to kanamycin (KM), but significantly lower rates of any resistance to protionamide (PTO) and mono-resistance to levofloxacin (LFX), and pre-XDR-TB (P<0.05). The proportion of resistance to other anti-TB drugs was not statistically different between the DR-TB with and without DM. Among DR-TB patients without and with DM, the proportion of patients with MDR-TB and pre-XDR-TB patterns showed a significant downward trend from 2016 to 2021 (P<0.05). Among DR-TB patients without DM, male, previously treated DR-TB cases, and immigration were risk factors for MDR-TB (P<0.05). In DR-TB patients with DM, a negative sputum smear is a risk factor for MDR-TB (P<0.05).

CONCLUSION

There was no statistical difference in resistance patterns between DR-TB with and without DM, except in arbitrary resistance to PTO and KM, mono-resistant SM and LFX, and pre-XDR-TB. Great progress has been made in the prevention and control of MDR-TB and pre-XDR-TB. However, DR-TB patients with and without DM differ in their risk factors for developing MDR-TB.

Development and Validation of a Nomogram for Prediction of QT Interval Prolongation in Patients Administered Bedaquiline-Containing Regimens in China: a Modeling Study

Corrected QT duration (QTc) interval prolongation is the most frequent adverse event associated with bedaquiline (BDQ) use. It may affect the safety of antituberculosis therapy, which leads to the consequent demands of needing to monitor during therapy. Our objective was to establish and validate a prediction model for estimating the risk of QTc prolongation after initiation of BDQ-containing regimens to multidrug-resistant tuberculosis (MDR-TB) patients. We constructed an individualized nomogram model based on baseline demographic and clinical characteristics of each patient within a Chinese cohort during BDQ treatment. The generalizability of this model was further validated through use of externally acquired data obtained from Beijing Chest Hospital from 2019 to 2020. Overall, 1,215 and 165 patients were included in training and external validation cohorts, respectively, whereby during anti-TB drug treatment, QTc prolongation was observed in 273 (22.5%) and 29 (17.6%) patients within these respective cohorts, for whom QTc values were >500 ms in 86 (31.5%) and 10 (34.7%) patients, respectively. Next, a total of four Cox proportional hazards models were created and assessed; then, nomograms derived from the models were plotted based on independent predictors of clofazimine, baseline QTc interval, creatinine, extensive drug-resistance (XDR), moxifloxacin, levofloxacin, and sex. Nomogram analysis revealed concordance index values of 0.723 (95% confidence interval [CI], 0.695 to 0.750) for the training cohort and 0.710 (95% CI, 0.627 to 0.821) for the external validation cohort, thus indicating relatively fair agreement between predicted and observed probabilities of QTc prolongation occurrence based on data obtained during 8-week, 16-week, and 24-week anti-TB treatment of both cohorts. Taken together, results obtained using these models demonstrated that coadministration of clofazimine and abnormal baseline QTc interval significantly contributed to QTc prolongation development during MDR-TB patient treatment with a BDQ-containing anti-TB treatment regimen.

Effectiveness and safety of bedaquiline-containing regimens for treatment on patients with refractory RR/MDR/XDR-tuberculosis: a retrospective cohort study in East China

OBJECTIVE

Refractory rifampicin-resistant/multidrug resistant/extensively-drug resistant tuberculosis (RR/MDR/XDR-TB) were defined as patients infected with Mycobacterium tuberculosis (MTB) resistant to rifampicin(RR-TB), or at least resistant to rifampicin and isoniazid (MDR-TB) or added resistant to fluoroquinolones (FQs) and one of second line injectable agents (XDR-TB), a patient for whom an effective regimen (fewer than 4 effective agents due to adverse events (AEs) or multiple drug resistances) cannot be developed. To compare the effectiveness and safety of bedaquiline (BDQ)-containing and BDQ-free regimens for treatment of patients with refractory RR/MDR/XDR-TB.

METHODS

Patients with refractory RR/MDR/XDR-TB receiving BDQ-containing regimens (BDQ group, n = 102) and BDQ-free regimens (non-BDQ group, n = 100) satisfied with included criteria were strictly included in this retrospective historical control study across East China. Culture conversion, treatment outcome, cavity closing rate, and AEs were compared between two groups.

RESULTS

The baseline characteristics involved all possible aspects of patients were well balanced between two groups (p > 0.05). Culture conversion rates in the BDQ group at month 3 (89.2% vs. 66.0%), month 6 (90.2% vs 72.0%), month 9 (91.2% vs. 66.0%), and month 12 (94.1% vs 65.0%) were all significantly higher than those in non-BDQ group (p < 0.001). Similar results were observed in the cavity closing rate at month 9 (19.6% vs 8.0%, p = 0.0) and month 12 (39.2% vs 15.0%, p < 0.001). Patients receiving BDQ-containing regimens had more treatment success than those receiving BDQ-free regimens (p < 0.001; cure rate, 69.6% vs. 45.0%; complete the treatment, 22.5% vs. 18.0%; treatment success, 92.2% vs. 63.0%); the use of BDQ and combined with Linezolid or Clofazimine or Cycloserine were identified as independent predictors of treatment success and no culture reversion (P < 0.05). AEs were similarly reported in 26.5% of patients in the BDQ group and 19.0% in the non-BDQ group (p = 0.2).

CONCLUSIONS

BDQ-containing regimens resulted in better treatment outcomes and similar safety relative to BDQ-free regimens for patients with refractory pulmonary RR/MDR/XDR-TB.

Bedaquiline-containing regimens and multidrug-resistant tuberculosis: a systematic review and meta-analysis

Objective:

Multidrug-resistant tuberculosis (MDR-TB) is a life-threatening infectious disease. Treatment requires multiple antimicrobial agents used for extended periods of time. The present study sought to evaluate the treatment success rate of bedaquiline-based regimens in MDR-TB patients.

Methods:

This was a systematic review and meta-analysis of studies published up to March 15, 2021. The pooled treatment success rates and 95% CIs were assessed with the fixed-effect model or the random-effects model. Values of p < 0.05 were considered significant for publication bias.

Results:

A total of 2,679 articles were retrieved by database searching. Of those, 29 met the inclusion criteria. Of those, 25 were observational studies (including a total of 3,536 patients) and 4 were experimental studies (including a total of 440 patients). The pooled treatment success rate was 74.7% (95% CI, 69.8-79.0) in the observational studies and 86.1% (95% CI, 76.8-92.1; p = 0.00; I² = 75%) in the experimental studies. There was no evidence of publication bias (p > 0.05).

Conclusions:

In patients with MDR-TB receiving bedaquiline, culture conversion and treatment success rates are high even in cases of extensive resistance.

Clinical standards for the dosing and management of TB drugs

BACKGROUND: Optimal drug dosing is important to ensure adequate response to treatment, prevent development of drug resistance and reduce drug toxicity. The aim of these clinical standards is to provide guidance on 'best practice´ for dosing and management of TB drugs.METHODS: A panel of 57 global experts in the fields of microbiology, pharmacology and TB care were identified; 51 participated in a Delphi process. A 5-point Likert scale was used to score draft standards. The final document represents the broad consensus and was approved by all participants.RESULTS: Six clinical standards were defined: Standard 1, defining the most appropriate initial dose for TB treatment; Standard 2, identifying patients who may be at risk of sub-optimal drug exposure; Standard 3, identifying patients at risk of developing drug-related toxicity and how best to manage this risk; Standard 4, identifying patients who can benefit from therapeutic drug monitoring (TDM); Standard 5, highlighting education and counselling that should be provided to people initiating TB treatment; and Standard 6, providing essential education for healthcare professionals. In addition, consensus research priorities were identified.CONCLUSION: This is the first consensus-based Clinical Standards for the dosing and management of TB drugs to guide clinicians and programme managers in planning and implementation of locally appropriate measures for optimal person-centred treatment to improve patient care.

Tuberculosis and comorbidities: treatment challenges in patients with comorbid diabetes mellitus and depression

Tuberculosis is one of the leading causes of death worldwide, primarily affecting low- and middle income countries and individuals with limited-resources within fractured health care systems. Unfortunately, the COVID-19 pandemic has only served to aggravate the already existing diagnostic gap, decreasing the number of people who get diagnosed and thereby complete successful treatment. In addition to this, comorbidities act as an external component that when added to the TB management equation, renders it even more complex. Among the various comorbidities that interact with TB disease, diabetes mellitus and depression are two of the most prevalent among non-communicable diseases within the TB population and merits a thoughtful consideration when the healthcare system provides care for them. TB patients with diabetes mellitus (TB-DM) or depression both have an increased risk of mortality, relapse and recurrence. Both of these diseases when in presence of TB present a ‘vicious-circle-like’ mechanism, meaning that the effect of each disease can negatively add up, in a synergistic manner, complicating the patient’s health state. Among TB-DM patients, high glucose blood levels can decrease the effectiveness of anti-tuberculosis drugs; however, higher doses of anti-tuberculous drugs could potentially decrease the effects of DM drugs. Among the TB-depression patients, not only do we have the adherence to treatment problems, but depression itself can biologically shift the immunological profile responsible for TB containment, and the other way around, TB itself can alter the hormonal balance of several neurotransmitters responsible for depression. In this paper, we review these and other important aspects such as the pharmacological interactions found in the treatment of TB-DM and TB-depression patients and the implication on TB care and pharmacological considerations.