Clinical and pharmacological hallmarks of rifapentine's use in diabetes patients with active and latent tuberculosis: do we know enough?

Tuberculosis-diabetes comorbidities: Mechanistic insights for clinical considerations and treatment challenges

Tuberculosis (TB) remains a leading cause of death among infectious diseases, particularly in poor countries. Viral infections, multidrug-resistant and ex-tensively drug-resistant TB strains, as well as the coexistence of chronic illnesses such as diabetes mellitus (DM) greatly aggravate TB morbidity and mortality. DM [particularly type 2 DM (T2DM)] and TB have converged making their control even more challenging. Two contemporary global epidemics, TB-DM behaves like a syndemic, a synergistic confluence of two highly prevalent diseases. T2DM is a risk factor for developing more severe forms of multi-drug resistant-TB and TB recurrence after preventive treatment. Since a bidirectional relationship exists between TB and DM, it is necessary to concurrently treat both, and promote recommendations for the joint management of both diseases. There are also some drug-drug interactions resulting in adverse treatment outcomes in TB-DM patients including treatment failure, and reinfection. In addition, autophagy may play a role in these comorbidities. Therefore, the TB-DM comorbidities present several health challenges, requiring a focus on multidisciplinary collaboration and integrated strategies, to effectively deal with this double burden. To effectively manage the comorbidity, further screening in affected countries, more suitable drugs, and better treatment strategies are required.

Drug-resistant strains of Mycobacterium tuberculosis: cell envelope profiles and interactions with the host

In the past few decades, drug-resistant (DR) strains of Mycobacterium tuberculosis (M.tb), the causative agent of tuberculosis (TB), have become increasingly prevalent and pose a threat to worldwide public health. These strains range from multi (MDR) to extensively (XDR) drug-resistant, making them very difficult to treat. Further, the current and future impact of the Coronavirus Disease 2019 (COVID-19) pandemic on the development of DR-TB is still unknown. Although exhaustive studies have been conducted depicting the uniqueness of the M.tb cell envelope, little is known about how its composition changes in relation to drug resistance acquisition. This knowledge is critical to understanding the capacity of DR-M.tb strains to resist anti-TB drugs, and to inform us on the future design of anti-TB drugs to combat these difficult-to-treat strains. In this review, we discuss the complexities of the M.tb cell envelope along with recent studies investigating how M.tb structurally and biochemically changes in relation to drug resistance. Further, we will describe what is currently known about the influence of M.tb drug resistance on infection outcomes, focusing on its impact on fitness, persister-bacteria, and subclinical TB.

Hypoalbuminemia and Pharmacokinetics: When the Misunderstanding of a Fundamental Concept Leads to Repeated Errors over Decades

Surprisingly, misinterpretation of the influence of hypoalbuminemia on pharmacokinetics and the clinical effects of drugs seems to be a current problem, even though hypoalbuminemia has no impact on the pharmacologically active exposure. Exceptions to this fact are highly protein-bound anaesthetics with high elimination capacity (i.e., <5 drugs on the market). To assess the frequency of misinterpretation of the influence of hypoalbuminemia on pharmacokinetics and the clinical effects of drugs between 1975 and 2021, a PubMed literature review was conducted. Each paragraph on albumin binding was classified as correct, ambiguous or incorrect, creating two acceptable categories: (1) content without any errors, and (2) content containing some incorrect and/or ambiguous statements. The analyses of these articles showed that fewer than 11% of articles contained no interpretation errors. In order to contain this misinterpretation, several measures are proposed: (1) Make the message accessible to a wide audience by offering a simplified and didactic video representation of the lack of impact of albumin binding to drugs. (2) Precise terminology (unbound/free form/concentration) should be used for highly bound drugs. (3) Unbound/free forms should be systematically quantified for highly plasma protein bound drugs for clinical trials as well as for therapeutic drug monitoring.

Potential Molecular Mechanisms of Ephedra Herb in the Treatment of Nephrotic Syndrome Based on Network Pharmacology and Molecular Docking

Objective

To explore the possible mechanisms of Ephedra herb (EH) in the treatment of nephrotic syndrome (NS) by using network pharmacology and molecular docking in this study.

Methods

Active ingredients and related targets of EH were obtained from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, and the gene names corresponding to the proteins were found through the UniProt database. Then, target genes related to NS were screened out from GeneCards, PharmGKB, and OMIM databases. Next, the intersection targets were obtained successfully through Venn diagram, which were also seen as key target genes of EH and NS. Cytoscape 3.9.0 software was used to construct the effective “active ingredient-target” network diagram, and “drug-ingredient-target-disease (D-I-T-D)” network diagram. After that, the STRING database was used to construct a protein-protein interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment involved in the targets were performed by the DAVID database and ClueGO plugin in Cytoscape. Finally, AutoDockTools software was used for molecular docking to verify the binding strength between main active ingredients and key target proteins.

Results

A total of 22 main active ingredients such as quercetin, kaempferol, luteolin, and naringenin were obtained, which could act on 105 targets related to NS. Through PPI network, 53 core targets such as AKT1, TNF, IL6, VEGFA, and IL1B were found, which might play a crucial role in the treatment of NS. Meanwhile, these targets were significantly involved in PI3K-Akt signaling pathway, TNF signaling pathway, AGE-RAGE signaling pathway, hepatitis B, and pathways in cancer through GO and KEGG enrichment analysis. The docking results indicated that active ingredients such as kaempferol, luteolin, quercetin, and naringenin all had good binding to the target protein AKT1 or TNF. Among them, luteolin and naringenin binding with AKT1 showed the best binding energy (-6.2 kcal/mol).

Conclusion

This study indicated that the potential mechanism of EH in treating NS may be related to PI3K-Akt signaling pathway, TNF signaling pathway, and AGE-RAGE signaling pathway, which provided better approaches for exploring the mechanism in treating NS and new ideas for further in vivo and in vitro experimental verifications.

Discovery and Development of Antibacterial Agents: Fortuitous and Designed

Today, antibacterial drug resistance has turned into a significant public health issue. Repeated intake, suboptimal and/or unnecessary use of antibiotics, and, additionally, the transfer of resistance genes are the critical elements that make microorganisms resistant to conventional antibiotics. A substantial number of antibacterials that were successfully utilized earlier for prophylaxis and therapeutic purposes have been rendered inadequate due to this phenomenon. Therefore, the exploration of new molecules has become a continuous endeavour. Many such molecules are at various stages of investigation. A surprisingly high number of new molecules are currently in the stage of phase 3 clinical trials. A few new agents have been commercialized in the last decade. These include solithromycin, plazomicin, lefamulin, omadacycline, eravacycline, delafloxacin, zabofloxacin, finafloxacin, nemonoxacin, gepotidacin, zoliflodacin, cefiderocol, BAL30072, avycaz, zerbaxa, vabomere, relebactam, tedizolid, cadazolid, sutezolid, triclosan and afabiacin. This article aims to review the investigational and recently approved antibacterials with a focus on their structure, mechanisms of action/resistance, and spectrum of activity. Delving deep, their success or otherwise in various phases of clinical trials is also discussed while attributing the same to various causal factors.

Completion Rate and Safety of Programmatic Screening and Treatment for Latent Tuberculosis Infection in Elderly Patients With Poorly Controlled Diabetic Mellitus: A Prospective Multicenter Study

BACKGROUND

Poor control of diabetes mellitus (DM) increases active tuberculosis (TB) risk. Understanding risk factors for latent TB infection (LTBI) in this population and intervention completion rates is crucial for policy making.

METHODS

Under a collaborative multidisciplinary team consisting of public health professionals, endocrinologists, and pulmonologists, patients aged >45 years with poorly controlled DM (pDM), defined as having a glycated hemoglobin level of ≥9% within the preceding year, were enrolled by endocrinologists from 2 hospitals; these patients underwent LTBI screening by using QuantiFERON (QFT). Once-weekly isoniazid and rifapentine for 12 weeks (3HP) or daily isoniazid for 9 months (9H) was administered by pulmonologists. QFT-positivity predictors were evaluated using logistic regression. Completion rates and safety were also investigated.

RESULTS

Among 980 patients with pDM (age: 64.2 ± 9.7 years), 261 (26.6%) were QFT-positive. Age, DM duration, chronic kidney disease stage ≥3, and dipeptidyl peptidase-4 inhibitor use, not using metformin, were associated with QFT-positivity. Preventive therapy (3HP: 138; 9H: 62) was administered in 200 (76.6%) QFT-positive patients. The completion rates of 3HP and 9H were 84.1% and 79.0%, respectively (P = .494). Nine (6.5%) and zero patients in the 3HP and 9H groups, respectively, developed systemic drug reactions (P = .059); 78.3% and 45.2% had ≥1 adverse drug reactions (P < .001); and post-treatment QFT conversion rates were 32% and 20%, respectively (P = .228).

CONCLUSIONS

LTBI prevalence exceeds 25% in elderly patients with pDM. Under care from a collaborative multidisciplinary team, the completion rate of preventive therapy, regardless of regimen could approach, or even exceed 80% in this population.

Completion and Adverse Drug Events of Latent Tuberculosis Infection Treatment in Patients Receiving Dialysis: Predictors and Impacts of Different Regimens in a Prospective Cohort Study

Although patients with end-stage renal disease receiving maintenance hemodialysis are at high risk for tuberculosis, the optimal treatment regimen for latent tuberculosis infection (LTBI) in this group has scarcely been studied for predictors of completion rate and adverse drug events (ADE). We prospectively enrolled dialysis patients for LTBI intervention from three medical centers in Taiwan. LTBI treatments were 3 months of weekly rifapentine plus isoniazid (3HP) and 9 months of daily isoniazid (9H). Completion rate, ADE, and reasons for treatment termination were recorded. Factors associated with treatment termination and ADE were analyzed using multivariate logistic regression. In all, 91 treatment courses (41 9H and 50 3HP) were surveyed. The completion rates were 61% for 9H and 82% for 3HP (P = 0.046). Use of 9H and development of ADE with a grade of ≥2 (≥grade 2 ADE) were associated with treatment termination. Hypersensitivity occurred in 29.2% of subjects in the 3HP group and 10.8% in the 9H group (P = 0.035) and independently correlated with 3HP regimen, diabetes mellitus (DM), and peritoneal dialysis (PD). Similarly, the independent predictors of ≥grade 2 ADE were use of 3HP regimen, presence of DM, and use of PD, whereas ≥grade 3 ADE were associated with eosinophil counts of >700/mm³ after 2 weeks of LTBI treatment even after adjustment for age and gender. In conclusion, for patients on dialysis, 3HP showed a higher rate of completion but also a higher rate of ≥grade 2 ADE than 9H. In addition, DM and PD were risk factors for ≥grade 2 ADE. Eosinophilia after 2-week treatment might be an alert for severe ADE.

A review of recent advances in anti-tubercular drug development

Tuberculosis is a global threat but in particular affects people from developing countries. It is thought that nearly a third of the population of the world live with its causative bacteria in a dormant form. Although tuberculosis is a curable disease, the chances of cure become slim as the disease becomes multidrug-resistant and the situation gets even worse as the disease becomes extensively drug-resistant. After approximately 5 decades without any new TB drug in the pipeline, there has been some good news in the recent years with the discovery of new drugs such as bedaquiline and delamanid as well as the discovery of new classes of anti-tubercular drugs. Some old drugs such as clofazimine, linezolid and many others which were not previously indicated for tuberculosis have been also repurposed for tuberculosis and they are performing well.

Hepatocytic transcriptional signatures predict comparative drug interaction potential of rifamycin antibiotics

Current strategies to treat tuberculosis (TB) and co-morbidities involve multidrug combination therapies. Rifamycin antibiotics are a key component of TB therapy and a common source of drug–drug interactions (DDIs) due to induction of drug metabolizing enzymes (DMEs). Management of rifamycin DDIs are complex, particularly in patients with co-morbidities, and differences in DDI potential between rifamycin antibiotics are not well established. DME profiles induced in response to tuberculosis antibiotics (rifampin, rifabutin and rifapentine) were compared in primary human hepatocytes. We identified rifamycin induced DMEs, cytochrome P450 (CYP) 2C8/3A4/3A5, SULT2A, and UGT1A4/1A5 and predicted lower DDIs of rifapentine with 58 clinical drugs used to treat co-morbidities in TB patients. Transcriptional networks and upstream regulator analyses showed FOXA3, HNF4α, NR1I2, NR1I3, NR3C1 and RXRα as key transcriptional regulators of rifamycin induced DMEs. Our study findings are an important resource to design effective medication regimens to treat common co-conditions in TB patients.