Long-Term Suppressive Therapeutic-Drug-Monitoring-Guided Dalbavancin Therapy for Cardiovascular Prosthetic Infections

Effect of body mass index on the timing of therapeutic drug monitoring-guided dalbavancin dosing in patients with osteoarticular infections

BACKGROUND

Recently, we documented that proactive therapeutic drug monitoring (TDM) allowed the successful individualization of the timing of dalbavancin administration in patients requiring prolonged antibiotic treatment. Here, we aimed to identify variables associated with the timing of TDM-guided dalbavancin dosing in patients who underwent proactive dalbavancin TDM.

METHODS

Adult patients who received at least three 1500 mg doses of dalbavancin for osteoarticular infections were included in the study. Univariate and multivariate linear regression analyses were performed, considering the timing of dalbavancin administrations as the dependent variable and clinical features as dependent covariates.

RESULTS

Sixty-three patients [65% male, mean (SD) age 64 ± 16 years] fulfilling the inclusion criteria were included in the study. Patients were given a mean (SD) 6.4 ± 5.0 injections of dalbavancin over a mean (SD) period of 198 ± 213 days. Dalbavancin was administered every 40 ± 7 days (range:16-71 days). By univariate linear regression analyses, patient age (P = 0.002), BMI (P < 0.001), serum albumin (P = 0.011) and the duration of dalbavancin treatment (P = 0.012) was found to be associated with the timing of dalbavancin administration. The BMI was the only variable retained in the final multivariate model (P < 0.001). A highly significant reduction in timing of dalbavancin administration was observed between patients with obesity, overweight and normal weight [mean (SD) 30 ± 7 versus 38 ± 4 versus 43 ± 7 days].

CONCLUSIONS

Overweight and obesity significantly impacted on dalbavancin pharmacokinetics in patients with osteoarticular infections requiring prolonged antibiotic treatment. These effects can be handled by proactive TDM.

Therapeutic drug monitoring of dalbavancin: A systematic review of strategies and clinical applications in the treatment of complex infections

INTRODUCTION

dalbavancin is approved for acute bacterial skin and soft tissue infections, but its off-label use in complex chronic infections has become increasingly common. Currently, no established dosing regimen exists for such infections. Given the need for prolonged treatments, a dose adjustment strategy based on therapeutic drug monitoring may optimize its use and allow for individualized regimens. This systematic review analyzes dalbavancin dosing in complex infections and TDM-based strategies to optimize treatment.

MATERIALS AND METHODS

A search was conducted in PubMed, Embase, Scopus, and the Cochrane Library (2014-2024) using the keywords: "dalbavancin", "pharmacokinetics", "pharmacodynamics", "therapeutic drug monitoring", and "TDM". Three independent reviewers selected and evaluated the studies. Clinical studies related to the pharmacokinetics of dalbavancin and the use of TDM in complex infections requiring prolonged regimens were included. Due to heterogeneity among studies, a qualitative analysis of the data was performed.

RESULTS

A total of 241 articles were identified. After removing duplicates and applying inclusion and exclusion criteria, 10 studies were included. These studies exhibited heterogeneity in design (6 retrospective and 4 prospective) and sample size, encompassing 457 patients and 1.298 samples. Most studies focused on osteoarticular infections treated with dalbavancin using an initial two-dose regimen of 1,500 mg administered one week apart, followed by dose adjustments based on plasma level monitoring. The most commonly targeted pharmacokinetic/pharmacodynamic parameters were a trough concentration above 8 μg/ml and an area under the curve/minimum inhibitory concentration ratio greater than 111.1. Therapeutic Drug Monitoring-Guided strategies were found to optimize dosing and maintain adequate plasma levels. Significant interindividual variability in plasma concentrations was observed, influenced by factors such as renal function and body surface area.

DISCUSSION

The use of Therapeutic Drug Monitoring in dalbavancin dosing optimizes the treatment of complex chronic infections by adjusting dosing intervals and maintaining adequate therapeutic levels over extended periods. However, further validation and definition of specific pharmacokinetic/pharmacodynamic targets are needed.

Usefulness of a hub and spoke TDM-guided expert clinical pharmacological advice program of dalbavancin for optimizing very long-term curative or suppressive treatment of chronic staphylococcal infections

A hub and spoke model for optimizing long-term treatment of chronic staphylococcal infections with dalbavancin based on therapeutic drug monitoring (TDM)-guided expert clinical pharmacological advice (ECPA) was implemented. This multicentric retrospective cohort study included patients receiving dalbavancin monotherapy lasting >6 weeks at different spoke hospitals having treatment optimized by means of a TDM-guided ECPA program at a hub hospital. Optimal pharmacokinetic/pharmacodynamic target against staphylococci with an MIC up to 0.125 mg/L was defined as dalbavancin concentrations >8.04 mg/L. Patients received dalbavancin therapy for curative (curative group) or suppressive (suppressive group) purposes. Clinical outcome was assessed by means of repeated ambulatory visits. A total of 12 spoke hospitals applied for 414 TDM-based ECPA for 101 patients, of whom 64.4% (65/101) were treated for curative and 35.6% (36/101) were for suppressive purposes. In the curative and suppressive groups, TDM-based ECPA optimized treatment for up to 14 and 28 months, respectively, and ensured median optimal exposure of 95.7% and 100%, respectively. In the curative group, having <70% of treatment time with concentrations above the optimal target increased failure risk [odds ratio (OR), 6.71; confidence interval (CI), 0.97-43.3; P = 0.05]. In the suppressive group, infective endocarditis was associated with an increased risk of ineffective treatment (OR, 8.65; CI, 1.29-57.62; P = 0.046). Mild adverse events were reported in 4.5% (5/101) of cases. A hub and spoke TDM-guided ECPA program of dalbavancin may be cost-effective for optimizing long-term treatment of chronic staphylococcal infections and for patients admitted to hospitals lacking in-house MD clinical pharmacologists.

Suppressive antibiotic treatment (SAT) in the era of MDRO infections: a narrative review

INTRODUCTION

Antibiotics were originally developed to treat acute bacterial infections, and research studies focus their efforts on safety and efficacy in the short term; however, prolonged course of antibiotics has been documented in multiple clinical settings. The aim of this narrative review is to provide a new perspective on SAT and to discuss new therapeuticpossibilities.

AREAS COVERED

We discuss new clinical scenarios in which SAT could be considered. We provided a broad discussion about long-acting agents and new or repurposed oral agents as well as the use of OPAT with elastomeric pumps and an overview of the pipeline of new antifungals. Limitations of SAT are presented in this review and especially patients' adherence issues, possible spread of MDROs, possible rising of the incidence of Clostridioides difficile infections, drug-to-drug interactions and drug-related problems, cost-effectiveness evaluation issues.

EXPERT OPINION

Many research gaps are evident and further studies are needed. Above all, the efficacy and safety of SAT in the different clinical scenarios. Discovery of new molecules against MDROs and ongoing research on PK/PD variables as well as a better understanding of the relationship between SAT and the emergence of resistance could improve SAT usage and reduce the impact of DRPs.

Multidose Dalbavancin Population Pharmacokinetic Analysis for Prolonged Target Attainment in Patients Requiring Long-Term Treatment

Introduction: Dalbavancin (DAL) is a long-acting lipoglycopeptide active against Gram-positive bacteria, including multidrug-resistant isolates. A growing body of evidence supports its efficacy in various difficult-to-treat infections. DAL shows time-dependent bactericidal activity in vitro at free drug concentrations equal to 4×MIC values. However, the optimal dosing scheme for achieving the PK/PD target in multidose treatment has not been fully established. Methods: Pharmacokinetic analysis was based on a nonlinear mixed effects modelling approach performed in NONMEM v7.5/Pirana, while R was used for data management and graphical summaries. Final model parameters were used to simulate the plasma disposition of DAL by Monte Carlo simulations to determine the multidose DAL regimen associated with a 90% target attainment of 100% fT > 4×MIC. Results: A two-compartmental model with first-order elimination and allometric-scaled bodyweight best described DAL disposition in patients with CLcr > 30 mL/min. Monte Carlo simulations showed that two 1500 mg DAL doses 7 days apart granted an optimal PTA > 90% of 100% fT > 4×MIC up to 5, 4, and 3 weeks in patients weighting from 40-80 kg, 80-120 kg and 120-200 kg, respectively. An additional third 1500 mg dose at the above time points by weight bands may extend the optimal PTA up to 9, 7, and 6 weeks of total treatment. Conclusions: Two 1500 mg DAL doses administered 7 days apart could be a valuable starting strategy for patients of all weight classes with CLcr > 30 mL/min. In patients requiring long-term DAL treatment, the optimal timing of additional administrations should be guided by routine TDM or empirically through patients' total body weight when TDM is unavailable.

A systematic review of dalbavancin efficacy as a sequential therapy for infective endocarditis

INTRODUCTION

Dalbavancin is an antibiotic characterized by an extended half-life and efficacy against methicillin-resistant Staphylococci. Currently, there are only narrative reviews summarizing the evidence about the use of dalbavancin for infective endocarditis (IE), many of which are focused primarily on its use as consolidation therapy. For this reason, we conducted a systematic review to describe the clinical efficacy and the safety of dalbavancin in IE treatment.

METHODS

We searched for available evidence using the MEDLINE (PubMed), Embase, Scopus, Cochrane Library and Web of Science libraries, with no restrictions regarding the publication year. The risk of bias was performed using the Cochrane ROBINS-I tool for the comparative studies and the Newcastle-Ottawa Scale for descriptive studies.

RESULTS

Nine studies were included. All of them were observational. Native valve endocarditis was the most common kind of IE found in the studies' populations (128/263, 48.7%), followed by prosthetic valve endocarditis, and cardiovascular implantable electronic device-related endocarditis. Coagulase-negative Staphylococci were the most common pathogens isolated (83/269, 30.1%), followed by S. aureus, Enterococci spp and Streptococci spp. Five out of nine studies documented a clinical failure rate of less than 10%. Dalbavancin showed a favourable safety profile. Dalbavancin appears to be a promising option for the consolidation therapy of IE. However, further studies comparing dalbavancin with standard of care are needed.

PROSPERO REGISTRATION NUMBER

CRD42023430032.

Therapeutic drug monitoring of antibiotics for methicillin-resistant Staphylococcus aureus infections: an updated narrative review for clinicians

BACKGROUND

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are associated with high mortality rates. Optimal antibiotic dosage plays a crucial role in reducing MRSA burden; thus, the use of therapeutic drug monitoring (TDM) in the clinical practice, especially of new drugs such as ceftobiprole, ceftaroline, dalbavancin, and oritavancin, should be implemented.

OBJECTIVES

We aim to examine and summarize the available evidence about TDM of anti-MRSA molecules, with a focus on pneumonia, endocarditis and vascular infections, and bone and joint infections.

SOURCES

We applied 'therapeutic drug monitoring' and 'Staphylococcus aureus' as search terms in PubMed, considering a time frame of 24 years (2001-2024). Articles in English language, non-duplicated, evaluating antibiotic therapeutic target, and role of TDM were included in the study.

CONTENT

In this review, available data for therapeutic target and TDM were critically analysed and summarized and suggestions about the use of old and new anti-MRSA antibiotics were provided, focusing on optimal dosages, tissue penetration according to infection types, and toxicity. Limitations to the widespread use of TDM in clinical practice were discussed.

IMPLICATIONS

The use of TDM may play an important role for the optimal management of patients with MRSA infections and may impact on patient outcomes by increasing efficacy and reducing the risk of adverse events. TDM may be implemented in clinical practice; however, several limitations such as the wide variability in the methodology and the need for skilled personnel need to be considered.

Global research trends in therapeutic drug monitoring of antimicrobials from 2000 to 2023: a bibliometric analysis

Objective

The practice of therapeutic drug monitoring (TDM) is widely used for maximizing the clinical efficacy of antimicrobials. However, a systematic bibliometric analysis providing an overview of this field is lacking at present. The aim of the current study was to identify hotspots and trends in antimicrobial TDM, highlight collaborations and influences among countries, institutions, and journals, and assess the knowledge base for further development of clinical research.

Research Design and Methods

Articles and reviews related to TDM of antimicrobials from the Web of Science Core Collection were collected. CiteSpace and VOSviewer, two visualization tools, were utilized to graphically assess the key elements within this domain, including mapping of countries and regions, institutions, keywords, and references associated with the field of antimicrobial TDM. Through this approach, we were able to successfully provide a comprehensive visual overview of the research landscape, highlighting the significant players and thematic trends in the literature.

Results

From 2000 to 2023, a total of 17,236 authors from 4,112 institutions in 112 countries/regions published 3,710 papers in 819 academic journals. The United States had the highest number of publications, with University of Queensland identified as the most active institution. The journal with the greatest number of publications was Therapeutic Drug Monitoring, whereas Antimicrobial Agents and Chemotherapy was the most co-cited journal. Current research focuses on pharmacokinetics, pharmacodynamics, vancomycin, posaconazole, invasive fungal infection and critically ill patients. Promising hotspots for future research include vancomycin, voriconazole, meropenem, isavuconazole, posaconazole, and teicoplanin. Moreover, vancomycin and critically ill patients remain a hot topic of future research.

Conclusion

Using bibliometric and visualization methods, the research hotspots of antimicrobial drugs in TDM were analyzed. The continued increase in the number of annual publications demonstrates the vital significance of TDM for antimicrobials. Data from this study provide a valuable reference for future research trends in TDM of antimicrobial agents.

Chronic antibiotic suppressive therapy with dalbavancin: a case series

Dalbavancin is a relatively new long-acting anti-Gram positive antimicrobial approved for the treatment of acute bacterial skin and skin structures infections. An increasing number of observational studies and case series were published on its off-label uses. Great interest is emerging about complicated cases where antibiotic treatment cannot be discontinued, and a chronic suppressive therapy is needed. We described a case series of 6 patients treated or ongoing on treatment with dalbavancin as chronic suppressive therapy (CAST) administered with the following regimen: dalbavancin 1500 mg on day 1 and 8 and then every 4 weeks. CAST median duration was 27 weeks. Five out of 6 patients reached a good clinical control of the infection (one of them completely resolved) while in one case we observed a recurrence of the infection. No adverse events were detected. Larger studies are needed to better clarify dalbavancin off-label uses and the most appropriate dose regimen.

Vascular Graft Infections: Updates on a Challenging Problem

Vascular graft infections (VGI) pose a significant challenge in vascular surgery, characterized by substantial morbidity and mortality. This review delves into the epidemiology, pathogenesis, microbiology, risk factors, and clinical presentation of VGI. It highlights diagnostic criteria and methodologies, including imaging techniques and laboratory tests. Comprehensive management strategies, involving antimicrobial therapy, surgical intervention, and preventive measures, are discussed. Emphasis is placed on the multidisciplinary approach required for effective treatment, alongside emerging trends in VGI microbiology and innovative therapeutic options. This review article aims to provide a detailed understanding of VGI for improved clinical outcomes.

Multidisciplinary Perspectives of Challenges in Infective Endocarditis Complicated by Septic Embolic-Induced Acute Myocardial Infarction

BACKGROUND

Infective endocarditis (IE) management is challenging, usually requiring multidisciplinary collaboration from cardiologists, infectious disease specialists, interventional cardiologists, and cardiovascular surgeons, as more than half of the cases will require surgical procedures. Therefore, it is essential for all healthcare providers involved in managing IE to understand the disease's characteristics, potential complications, and treatment options. While systemic embolization is one of the most frequent complications of IE, the coronary localization of emboli causing acute myocardial infarction (AMI) is less common, with an incidence ranging from 1% to 10% of cases, but it has a much higher rate of morbidity and mortality. There are no guidelines for this type of AMI management in IE.

METHODS

This narrative review summarizes the current knowledge regarding septic coronary embolization in patients with IE. Additionally, this paper highlights the diagnosis and management challenges in such cases, particularly due to the lack of protocols or consensus in the field.

RESULTS

Data extracted from case reports indicate that septic coronary embolization often occurs within the first two weeks of the disease. The aortic valve is most commonly involved with vegetation, and the occluded vessel is frequently the left anterior descending artery. Broad-spectrum antibiotic therapy followed by targeted antibiotic therapy for infection control is essential, and surgical treatment offers promising results through surgical embolectomy, concomitant with valve replacement or aspiration thrombectomy, with or without subsequent stent insertion. Thrombolytics are to be avoided due to the increased risk of bleeding.

CONCLUSIONS

All these aspects should constitute future lines of research, allowing the integration of all current knowledge from multidisciplinary team studies on larger patient cohorts and, subsequently, creating a consensus for assessing the risk and guiding the management of this potentially fatal complication.

Proactive therapeutic monitoring of dalbavancin concentrations in the long-term management of chronic osteoarticular/periprosthetic joint infections

Here, we describe the use of proactive therapeutic drug monitoring (TDM) to individualize the optimal timing of drug injections in 16 adult patients with chronic osteoarticular infections receiving a median of 7 injections of dalbavancin (up to 12 injections in 15 months). Dalbavancin injections were repeated at medians of 39-47 days, with infusion intervals ranging from 26 to 69 days. TDM can facilitates a precise, targeted use of dalbavancin for infections requiring prolonged treatments.