Clinical Pharmacokinetics and Pharmacodynamics of Dalbavancin

Peptide therapeutics: current status and future opportunity with focus on nose-to-brain delivery☆

Peptide drugs are a highly diverse group of therapeutic agents. Over the last decade, more than 40 peptides have been approved for clinical use. They target different structures, ranging from G protein-coupled receptors (GPCRs) to pathogens and are used to treat a variety of indications, including metabolic disorders, genetic diseases, acute illnesses and more. Structurally, peptide therapeutics are a heterogeneous class. This diversity allows them to bridge the gap between small molecules and biologics. However, limited metabolic stability and bioavailability must be addressed. Strategies to improve the half-life include backbone and sequence modification, cyclization and the addition of stabilizing moieties. Great strides have been made in recent years towards achieving sufficient drug uptake for oral application have been achieved within recent years. However, these methods require specialized peptide design or involve permeabilization of the gastrointestinal tract. Consequently, other routes of administration are being explored. One promising approach is the nasal application of peptides. This method can be used for systemic uptake, but also allows for direct nose-to-brain delivery of compounds. While successful nose-to-brain delivery is already used in the clinic, the underlining mechanisms are poorly understood. Strategies for rational optimization are needed to make this method more applicable to a wider range of compounds. Overall, approved peptide therapeutics cover a wide range of applications and have demonstrated a growing and novel potential in recent drug discovery.

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.

Management of methicillin-resistant Staphylococcus aureus bloodstream infections: a comprehensive narrative review of available evidence focusing on current controversies and the challenges ahead

INTRODUCTION

Bloodstream infections (BSIs) caused by Staphylococcus aureus are common worldwide, representing one of the most relevant issues in clinical infectious diseases practice. In particular, BSIs by methicillin-resistant S. aureus (MRSA-BSI) are still today a challenge since mortality burden remains elevated although decades of research.

AREAS COVERED

The following topics regarding MRSA-BSI were reviewed and discussed by resorting to best available evidence retrieved from PubMed/MEDLINE up to October 2024: i) epidemiology; ii) microbiology; iii) classification, with a focus on complicated and not complicated forms; iv) the structured approach to the patient; v) pharmacokinetics and pharmacodynamics of the main antimicrobial options; vi) controversies regarding the best therapeutic approach.

EXPERT OPINION

Despite ongoing efforts to better stratify and manage MRSA-BSI, there is no universally accepted classification system accurately distinguishing between uncomplicated/low risk and complicated/high risk forms. Biomarkers such as interleukin(IL)-10 hold promise in order to enable a more precise stratification, premise for an appropriate treatment plan. There is a theoretical rationale for implementing a combination therapy including a beta-lactam agent upfront, especially for patients considered at higher risk of unfavorable outcomes, but further data are necessary, and the same applies to newer adjuvants. Novel microbiological techniques may help in guiding antimicrobial duration.

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.

One and Done? An Evaluation of the Clinical Outcomes of Single- and Multi-Dose Dalbavancin Use in the Pediatric Population

Staphylococcus aureus is a leading cause of invasive bacterial infections in the pediatric population. In general, data surrounding the use of newly approved antimicrobials within children are lacking. Dalbavancin is a long-acting lipoglycopeptide that shows promise for off-label use in adults given its unique pharmacokinetics and in vitro potency against common Gram-positive isolates; however, evidence to supports its use in children is limited. We report the use of dalbavancin in three pediatric cases in patients aged 17 months of age, 3 years of age, and 11 years of age. All infections were caused by S. aureus (66.7% methicillin-resistant S. aureus) representing varied disease, including an osteoarticular infection and catheter-related bloodstream infection. Furthermore, all patients had pediatric infectious diseases involvement. Following the utilization of DAL, high clinical success and low rates of adverse effects were observed with high patients' and parents' satisfaction. While larger, confirmatory real-world studies are needed, our findings support safe off-label DAL use in select pediatric patients.

Synthetic approaches and therapeutic applications of FDA-approved antibacterial agents: A comprehensive review from 2003 to 2023

The increasing threat of antibiotic resistance has necessitated the development of new antibacterial agents. 33 novel antibacterial agents have been approved by the U.S. Food and Drug Administration (FDA) within the two-decade timeframe from 2003 to 2023. These novel antibacterial agents included new chemical classes, such as lipopeptides, 18-membered macrolides, diaromatic quinolones, and nitroimidazoles, as well as modified existing classes, such as quinolones, tetracyclines, β-lactams, macrolides, oxazolidinones, and aminoglycosides. Nonetheless, during these twenty years, approval for new antibiotics was notably absent in 6 different years, and the total number of antibiotics approved was considerably less than that of other drug classes, including anticancer drugs. In this review, we provide an extensive analysis of the synthetic approaches and therapeutic applications of these approved antibacterial agents. We believe that this review will help further research on potential antibacterial agents for clinical use and development of next generation of antibacterial agents.

Real-World Use of Dalbavancin in a United States Tertiary Referral Center

Introduction Outpatient management of serious bacterial infections can be difficult particularly in situations where outpatient parenteral antibiotic therapy may be difficult due to patient-specific factors such as history of medical non-compliance, unstable housing situations, and individuals who use injection drugs. Dalbavancin is a long-acting lipoglycopeptide antibiotic currently approved for the treatment of bacterial skin and soft tissue infections; however, it is often employed in the management of other infections caused by gram-positive organisms. Data regarding the off-label usage of dalbavancin remains an emerging area of study. Methods A retrospective cohort study of all 52 inpatients, ages 18-56, who received ≥1 dose of dalbavancin between November 2017 and February 2023 was conducted. Rates of treatment completion and clinical cure were assessed at 42 days post-dalbavancin treatment. Results Fifty-two adults were identified. Dalbavancin was used to treat skin/soft tissue infections in 12 patients (23.5%). Off-label uses accommodated for 40 patients, with diagnoses including as follows: bloodstream infection (21, 41.2%), osteomyelitis (12, 23.5%), septic arthritis (10, 13.3%), native valve infective endocarditis (six, 11.8%), prosthetic joint infection (three, 5.9%), epidural abscess (three, 5.9%), catheter-related bloodstream infection (one, 2%), and other infections (13, 25.5%). Among patients who completed therapy, cure, as assessed at day 42, was achieved in 35 (67.6%) patients. Intravenous (IV) drug and the need for facility placement to receive IV antibiotics use were the commonly cited reasons for dalbavancin utilization. Adverse events included mild elevation in serum aminotransferases which occurred in six patients (11.5%) and acute kidney injury which occurred in two (3.8%). There were no adverse events resulting in drug discontinuation. Conclusions Dalbavancin use, including off-label indications, such as bacteremia, septic arthritis, osteomyelitis, prosthetic joint infection, and others, appears safe and associated with favorable treatment responses. Therefore, it can be considered as an alternative treatment approach in patients who may not be candidates for traditional outpatient parenteral antimicrobial therapy.

Glycopeptides: Insights Towards Resistance, Clinical Pharmacokinetics and Pharmacodynamics

Glycopeptides have emerged as life-saving therapeutics in treating various gram-positive bacterial infections. Vancomycin being the first therapeutically approved glycopeptide has turned out as a blockbuster drug in the mitigation of gram-positive infections. However, long-term misuse of these glycopeptides led to the development of resistance which became a bottleneck in tackling various infections. Antimicrobial resistance has become a global threat exposing their impact on the public health domain. Concomitant to this the second-generation glycopeptides were developed through structural alterations and were approved by the USFDA which are serving as a last resort for an effective treatment. However, resistance against these also might develop shortly when misused. In this aspect, strategic approaches concerning structural activity for enhancing the antimicrobial activity and overcoming resistance were conferred. The clinical use of glycopeptides were also limited due to associated toxicity concerns and unusual pharmacokinetics. Understanding the pharmacokinetics of glycopeptides in different clinical conditions are necessary in tackling drug-induced resistance due to overdosing. Hence, dose optimization and therapeutic drug monitoring in different clinical conditions is necessary for better safety profiles and toxicity reduction. So, this review provides insights into glycopeptide-induced resistances, aspects of structural modifications to overcome resistance and their implications on pharmacokinetics and pharmacodynamics in different clinical conditions.

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.

Bridging the Gap: A Systematic Review with Expert Opinion on the Use of Dalbavancin for In-Label and Off-Label Indications in Pediatric Patients

OBJECTIVES

The aim of this work was to perform a systematic review assessing the pharmacokinetic/pharmacodynamic (PK/PD) properties of dalbavancin and the clinical use for in-label and off-label indications in pediatric patients.

METHODS

Two authors independently searched the PubMed-MEDLINE and Scopus databases and clinicaltrials.gov up to 20 November 2024, to retrieve randomized controlled trials (RCTs), observational studies, PK studies, and case series/reports assessing dalbavancin PK/PD properties or the clinical use for both in-label and off-label indications in pediatric patients. Data were independently extracted by the two authors, and the quality of the included studies was independently assessed by means of specific tools according to study design. Clinical success was selected as the primary outcome. Descriptive statistics were used for summarizing the retrieved data. Subgroup analysis according to PK/PD data, as well as in-label and off-label indications, was performed.

RESULTS

After screening 206 articles, nine studies were included in the systematic review (one RCT, three PK studies, and five case series/reports; n = 267). Dalbavancin exposure was 30% lower in pediatric patients compared to adults. In acute bacterial skin and skin structure infections (ABSSSIs), the overall clinical success of dalbavancin was 96.1-97.3% and 92.9% in RCT and case series, respectively. Bone and joint infections (60.7%) and central-line-associated bloodstream infections (14.3%) represented the most common dalbavancin off-label indications in pediatric patients. Overall, the clinical success for off-label indications was 92.9%. The rate of adverse events ranged from 7.1% to 10.7%.

CONCLUSIONS

Our systematic review summarized evidence concerning the PK/PD properties of dalbavancin and its use for in-label or off-label indications in pediatric patients. The available findings suggest that dalbavancin may be a valuable alternative for the management of ABSSSIs and/or off-label indications in pediatric patients according to efficacy and safety data, allowing for a potential minimized duration of hospital stay.

Dalbavancin Use in Bone and Joint Infections

Background

Dalbavancin (DAL) off-label use for treating bone and joint infections has increased especially as long-term intravenous access is not needed. Little is known about the effectiveness and safety of its use.

Methods

This retrospective, single-center, descriptive study included adults treated with DAL for bone or joint infections over a 4-year period (2019-2023). Patient demographics, infection type and location, pre-DAL antibiotic and surgical treatments, indication for DAL, and clinical outcomes were collected. Risk factor analysis for 1-year infection recurrence was performed.

Results

There were 58 patient encounters of bone and/or joint infections treated with DAL. The majority of patients were treated for osteomyelitis (81.0%) followed by native (8.6%) and peri-prosthetic (10.4%) joint infection. Fifty (86.2%) patients underwent surgical intervention, and 17 (68%) of the 25 patients with infected hardware had full hardware removal. The most common pathogen identified was Staphylococcus aureus (41; 70.7%), with methicillin-resistant Staphylococcus aureus isolated in 23 (40.0%) cases. Ten (17.2%) patients had recurrence within 1 year. Hardware removal was found to significantly decrease the risk of infection recurrence (P = .026). None of the peri-prosthetic joint infection patients had infection recurrence within 1 year.

Conclusions

Our findings support DAL as an effective treatment for bone and joint infection when combined with surgical debridement and hardware removal. Failure to remove infected hardware significantly increased the risk of infection recurrence within 1 year. Randomized controlled trials are needed to further support DAL as a novel treatment for orthopedic infections.

Population Pharmacokinetics and Pharmacodynamics of Dalbavancin and C-Reactive Protein in Patients with Staphylococcal Osteoarticular Infections

BACKGROUND AND OBJECTIVE

Dalbavancin is increasingly used for the long-term treatment of chronic osteoarticular infections. A population pharmacokinetic/pharmacodynamic (PK/PD) analysis for assessing the relationship between dalbavancin exposure and C-reactive protein (C-RP) over time was conducted.

METHODS

Non-linear mixed-effect modeling was fitted to dalbavancin and C-RP concentrations. Monte Carlo simulations assessed the weekly percentage of C-RP reduction associated with different dosing regimens, starting from baseline to < 1 mg/dL.

RESULTS

A total of 45 patients were retrospectively included in the analysis. The PK of dalbavancin was described by a two-compartment model, and the PD of C-RP was described by an indirect turnover maximum inhibition model. The total dalbavancin concentration model estimate producing 50% of maximum C-RP production inhibition (IC50) was 0.70 mg/L. Monte Carlo simulations showed that in patients with staphylococcal osteoarticular infections targeting total dalbavancin concentrations at > 14.5 mg/L at any time point may achieve C-RP production inhibition over time in > 95% of patients. Based on this, the findings showed that a cumulative dose of 3000 mg administered in the first 3 weeks may lead to a > 90% C-RP decrease versus baseline in approximately 5-6 weeks. In patients needing treatment prolongation, an additional 1500 mg dose after this period may maintain C-RP concentrations < 1 mg/dL for other 3 weeks.

CONCLUSIONS

A decrease in C-RP is related to dalbavancin exposure in osteoarticular infections. Targeting dalbavancin plasma concentrations above the efficacy threshold may be associated with effective treatment.

Cell-wall-anchored proteins affect invasive host colonization and biofilm formation in Staphylococcus aureus

As a major human and animal pathogen, Staphylococcus aureus can attach to medical implants (abiotic surface) or host tissues (biotic surface), and further establish robust biofilms which enhances resistance and persistence to host immune system and antibiotics. Cell-wall-anchored proteins (CWAPs) covalently link to peptidoglycan, and largely facilitate the colonization of S. aureus on various surfaces (including adhesion and biofilm formation) and invasion into host cells (including adhesion, immune evasion, iron acquisition and biofilm formation). During biofilm formation, CWAPs function in adhesion, aggregation, collagen-like fiber network formation, and consortia formation. In this review, we firstly focus on the structural features of CWAPs, including their intracellular function and interactions with host cells, as well as the functions and ligand binding of CWAPs in different stages of S. aureus biofilm formation. Then, the roles of CWAPs in different biofilm processes with regards in development of therapeutic approaches are clarified, followed by the association between CWAPs genes and clonal lineages. By touching upon these aspects, we hope to provide comprehensive knowledge and clearer understanding on the CWAPs of S. aureus and their roles in biofilm formation, which may further aid in prevention and treatment infection and vaccine development.

Dalbavancin as suppressive therapy for implant-related infections: a case series with therapeutic drug monitoring and review of the literature

Implant-related infections may need suppressive antibiotic therapy (SAT). We describe a SAT strategy using dalbavancin with therapeutic drug monitoring (TDM). This is a retrospective bicentric study of patients with implant-related infection who received dalbavancin SAT between January 2021 and September 2023. Fifteen patients were included. Median number of injections was 4 (IQR: 2-7). Median time between two reinjections was 57 days (IQR 28-82). Dalbavancin plasma concentrations were above 4 mg/L for 97.9% of dosages (93/95) and above 8 mg/L for 85% (81/95). These results support the use of dalbavancin SAT for implant-related infections.

[Outpatient parenteral anti-infective therapy (OPAT)]

Outpatient parenteral anti-infective therapy (OPAT) involves the administration of intravenous anti-infectives outside a hospital setting. This shortens the inpatient stay and leads to a reduction in treatment costs, fewer instances of nosocomial infections and enhanced quality of life for the patient.

Updated antimicrobial dosing recommendations for obese patients

The prevalence of obesity has increased considerably in the last few decades. Pathophysiological changes in obese patients lead to pharmacokinetic (PK) and pharmacodynamic (PD) alterations that can condition the correct exposure to antimicrobials if standard dosages are used. Inadequate dosing in obese patients can lead to toxicity or therapeutic failure. In recent years, additional antimicrobial PK/PD data, extended infusion strategies, and studies in critically ill patients have made it possible to obtain data to provide a better dosage in obese patients. Despite this, it is usually difficult to find information on drug dosing in this population, which is sometimes contradictory. This is a comprehensive review of the dosing of different types of antimicrobials (antibiotics, antifungals, antivirals, and antituberculosis drugs) in obese patients, where the literature on PK and possible dosing strategies in obese adults was critically assessed.

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.

New Antibiotics for the Treatment of Nosocomial Central Nervous System Infections

Nosocomial central nervous system (CNS) infections with carbapenem- and colistin-resistant Gram-negative and vancomycin-resistant Gram-positive bacteria are an increasing therapeutic challenge. Here, we review pharmacokinetic and pharmacodynamic data and clinical experiences with new antibiotics administered intravenously for the treatment of CNS infections by multi-resistant bacteria. Cefiderocol, a new siderophore extended-spectrum cephalosporin, pharmacokinetically behaves similar to established cephalosporins and at high doses will probably be a valuable addition in our therapeutic armamentarium for CNS infections. The new glycopeptides dalbavancin, telavancin, and oritavancin are highly bound to plasma proteins. Although effective in animal models of meningitis, it is unlikely that they reach effective cerebrospinal fluid (CSF) concentrations after intravenous administration alone. The β-lactam/β-lactamase inhibitor combinations have the principal problem that both compounds must achieve adequate CSF concentrations. In the commercially available combinations, the dose of the β-lactamase inhibitor tends to be too low to achieve adequate CSF concentrations. The oxazolidinone tedizolid has a broader spectrum but a less suitable pharmacokinetic profile than linezolid. The halogenated tetracycline eravacycline does not reach CSF concentrations sufficient to treat colistin-resistant Gram-negative bacteria with usual intravenous dosing. Generally, treatment of CNS infections should be intravenous, whenever possible, to avoid adverse effects of intraventricular therapy (IVT). An additional IVT can overcome the limited penetration of many new antibiotics into CSF. It should be considered for patients in which the CNS infection responds poorly to systemic antimicrobial therapy alone.

Implementation and validation of a Bayesian method for accurately forecasting duration of optimal pharmacodynamic target attainment with dalbavancin during long-term use for subacute and chronic staphylococcal infections

Dalbavancin is increasingly being used for long-term treatment of subacute and chronic staphylococcal infections. In this study, a new Bayesian model was implemented and validated using MwPharm software for accurately forecasting the duration of pharmacodynamic target attainment above the efficacy thresholds of 4.02 mg/L or 8.04 mg/L against staphylococci. Forecasting accuracy improved substantially with the a posteriori approach compared with the a priori approach, particularly when two measured concentrations were used. This strategy may help clinicians to estimate the duration of optimal exposure with dalbavancin in the context of long-term treatment.

Usefulness of dalbavancin in early discharge and nonhospitalization. It's time to throw your heart over the obstacle?

Introduction

Dalbavancin is a semisynthetic lipoglycopeptide long-acting antibiotic approved for the treatment of acute bacterial skin and skin structure infections (ABSSSIs). Its features can be useful in the current healthcare scenario characterized by the shortage of available hospital beds.

Materials methods and results

We implemented several actions in order to optimize the use of dalbavancin allowing an improvement strategy both from the healthcare system and the patient's perspective in two hospital settings. In the Emergency Department we hospitalized only patients who met the clinical criteria and not the logistic criteria (i.e., the need for antibiotic therapy infusion). During the years 2017-2023, this strategy was applied in 40 cases, thus avoiding 40 hospitalizations for a total saving of 280 days of hospitalization.In the Internal Medicine ward and surgery department when there was no longer any need for hospitalization, we discharged the patient as early as possible. During the years 2017-2023, this strategy was applied in 189 cases, saving at least 1,134 days of hospitalization. The outcome of the treated patients was favorable in 228 out of 229 patients (99.5%).

Conclusions

Our experience using dalbavancin in ABSSSI has been very satisfactory overall. The efficacy was close to 100%. Minor adverse events of slight severity occurred rarely. At the same time, this strategy allowed a more efficient allocation of hospital beds. Dalbavancin presents an ideal pharmacodynamic/pharmacokinetic profile for the management of ABSSSI especially in settings where shortage of hospital beds is critical.

Therapeutic Drug Monitoring of Dalbavancin in Real Life: A Two-Year Experience

Dalbavancin is a long-acting lipoglycopeptide that is registered for the treatment of acute bacterial skin and skin structure infections, and it is also increasingly used for infections that require prolonged antibiotic treatment. Here, we present the results from the first 2 years of a service set up in December 2021 for the therapeutic drug monitoring (TDM) of dalbavancin in clinical settings. In particular, we compared the trough concentration (Cmin) to maximum concentration (Cmax) in patients with osteoarticular infections receiving prolonged treatment with dalbavancin. Log-linear regression models were used to estimate the timing of dalbavancin administration with the goal of maintaining Cmin concentrations of >8 mg/L in the two TDM-based strategies. From December 2021 to November 2023, 366 TDMs of dalbavancin from 81 patients were performed. The Cmin and Cmax concentrations of dalbavancin ranged from 4.1 to 70.5 mg/L and from 74.9 to 995.6 mg/L, respectively. With log-linear regression models, we estimated that each injection should be administered every 42-48 days to maintain the Cmin concentrations. Out of the 81 patients, 37 received at least three doses of dalbavancin for the treatment of osteoarticular infections. Despite there being no significant differences in the days of dalbavancin treatment (130 ± 97 versus 106 ± 102 days), the patients in the Cmax-based TDM group received a significantly lower number of dalbavancin injections (5.2 ± 1.8 versus 7.3 ± 2.6 injections, p = 0.005), and they were administered over a longer period of time (40 ± 10 versus 29 ± 14 days, p = 0.013) than in the Cmin-based TDM group. In conclusion, Cmax-based TDM was associated with a significant reduction in the inter-individual variability of dalbavancin concentrations and lower drug dosing frequency than those of Cmin-based TDM. This approach could, therefore, favor a more rational and targeted use of dalbavancin in patients requiring prolonged treatment.

Dalbavancin in Bone and Joint Infections: A Systematic Review

BACKGROUND

Approved for acute bacterial skin and skin structure infections, dalbavancin (DBV) has gradually acquired over the years a role as an off-label treatment for several infections caused by Gram-positive bacteria even in other anatomical sites. Osteoarticular (OA) infections are one of the most difficult-to-treat infections and, since the absence of recommendations, clinicians use different and heterogenic DBV dosing schedule regimens for the off-label treatment of osteomyelitis, spondylodiscitis, and septic arthritis. Our aim is to systematically review the current literature to describe DBV administration schedules and their outcome in OA infections.

METHODS

According to the 2020 updated PRISMA guidelines, all peer-reviewed articles regarding the use of DBV in OA infections were included. We conducted a literature search on PubMed and Cochrane Controlled Trials.

RESULTS

A total of 23 studies and 450 patients were included, prevalently male (144/195, 73.8%) and diabetic (53/163, 32.5%). Overall, 280 (280/388, 72.2%) osteomyelitis, 79 (79/388, 20.4%) spondylodiscitis, and 29 (29/388, 7.5%) septic arthritis were considered. Staphylococcus aureus (164/243, 67.5%) was the most common pathogen isolated. A previous treatment failure (45/96, 46.9%) was the main reason for a switch to a long-acting antibiotic. Most patients were successfully cured with DBV (318/401, 79.3%). A source control was performed in most patients with a favourable outcome (80.4%), while MRSA was prevalently isolated in people with an unfavourable outcome (57%). While a higher percentage of success was found in people who received three doses of DBV 1 week apart (92.3%), a higher rate of treatment failure was recorded in cases of when the DBV cycle was composed of less than two or more than four doses (27.8%).

CONCLUSIONS

DBV has shown to be effective as a treatment for OA infections. The most favourable outcome was found in patients receiving three doses of DBV and with an adequate surgical management prior to antibiotic treatment. Although a rigorous administration schedule does not exist, DBV is a viable treatment option in the management of OA infections.

The expert clinical pharmacological advice program for tailoring on real-time antimicrobial therapies with emerging TDM candidates in special populations: how the ugly duckling turned into a swan

INTRODUCTION

The growing spread of infections caused by multidrug-resistant pathogens makes the need of tailoring antimicrobial therapies by means of a 'patient-centered' approach fundamental. In this scenario, therapeutic drug monitoring (TDM) of emerging antimicrobial candidates may be a valuable approach, but expert interpretation of TDM results should be granted for making them more clinically useful. The MD Clinical Pharmacologist may take over this task since this specialist may couple PK/PD expertise on drugs with a medical background and may provide expert interpretation of TDM results of antimicrobials for tailoring therapy on real-time in each single patient based on specific both drug/pathogen issues and patient issues.

AREAS COVERED

This article aims to highlight the main key-points and organizational aspects for implementing a successful TDM-based expert clinical pharmacological advice (ECPA) program for tailoring antimicrobial therapies on real-time in different hospitalized patient special populations.

EXPERT OPINION

TDM-based ECPA programs lead by the MD Clinical Pharmacologist may represent a way forward for maximizing clinical efficacy and for minimizing the risk of resistance developments and/or toxicity of antimicrobials. Stakeholders should be aware of the fact that this innovative approach may be cost-effective.

The Challenge of Emerging Resistant Gram-Positive Pathogens in Hip and Knee Periprosthetic Joint Infections

➤ An increase in resistant bacterial pathogens has occurred over the last 4 decades.➤ Careful patient selection and improving or correcting risk factors for periprosthetic joint infection (PJI) before elective surgical treatment are strongly recommended. ➤ Appropriate microbiological methods, including those used to detect and grow Cutibacterium acnes, are recommended. ➤ Antimicrobial agents used in the prevention or management of infection should be selected appropriately and the duration of therapy should be carefully considered in order to mitigate the risk of developing bacterial resistance.➤ Molecular methods including rapid polymerase chain reaction (PCR) diagnostics, 16S sequencing, and/or shotgun and/or targeted whole-genome sequencing are recommended in culture-negative cases of PJI.➤ Expert consultation with an infectious diseases specialist (if available) is recommended to assist with the appropriate antimicrobial management and monitoring of patients with PJI.

Treatment of Enterococcus faecalis Infective Endocarditis: A Continuing Challenge

Today, Enterococcus faecalis is one of the main causes of infective endocarditis in the world, generally affecting an elderly and fragile population, with a high mortality rate. Enterococci are partially resistant to many commonly used antimicrobial agents such as penicillin and ampicillin, as well as high-level resistance to most cephalosporins and sometimes carbapenems, because of low-affinity penicillin-binding proteins, that lead to an unacceptable number of therapeutic failures with monotherapy. For many years, the synergistic combination of penicillins and aminoglycosides has been the cornerstone of treatment, but the emergence of strains with high resistance to aminoglycosides led to the search for new alternatives, like dual beta-lactam therapy. The development of multi-drug resistant strains of Enterococcus faecium is a matter of considerable concern due to its probable spread to E. faecalis and have necessitated the search of new guidelines with the combination of daptomycin, fosfomycin or tigecycline. Some of them have scarce clinical experience and others are still under investigation and will be analyzed in this review. In addition, the need for prolonged treatment (6–8 weeks) to avoid relapses has forced to the consideration of other viable options as outpatient parenteral strategies, long-acting administrations with the new lipoglycopeptides (dalbavancin or oritavancin), and sequential oral treatments, which will also be discussed.

Acute bacterial skin and skin structure infections in pediatric patients: potential role of dalbavancin

INTRODUCTION

Acute bacterial skin and skin structure infections (ABSSSIs) are a subtype of skin and soft tissue infections (SSTI), usually sustained by Gram-positive bacteria, whose incidence is high among children. ABSSSIs are responsible for a considerable number of hospitalizations. Moreover, as multidrug resistant (MDR) pathogens become widespread, the pediatric category seems burdened with an increased risk of resistance and treatment failure.

AREAS COVERED

To obtain a view on the status of the field, we describe the clinical, epidemiological, and microbiological aspects of ABSSSI in children. Old and new treatment options were critically revised with a focus on the pharmacological characteristics of dalbavancin. Evidence on the use of dalbavancin in children was collected, analyzed, and summarized.

EXPERT OPINION

Many of the therapeutic options available at the moment are characterized by the need for hospitalization or repeated intravenous infusions, safety issues, possible drug-drug interactions, and reduced efficacy on MDRs. Dalbavancin, the first long-acting molecule with strong activity against methicillin-resistant and also many vancomycin-resistant pathogens represents a game changer for adult ABSSSI. In pediatric settings, the available literature is still limited, but a growing body of evidence supports dalbavancin use in children with ABSSSI, demonstrating this drug to be safe and highly efficacious.

Dalbavancin in the treatment of acute bacterial skin and skin structure and other infections: a safety evaluation

INTRODUCTION

Dalbavancin is a second-generation lipoglycopeptide that was approved since 2014 to treat acute bacterial skin and skin-structure infections (ABSSSI). Dalbavancin is characterized by Gram-positive activity and novel pharmacokinetic properties that result in a prolonged terminal half-life, allowing once weekly dosing in adults. A good safety profile was reported by randomized clinical trials and meta-analyses.

AREAS COVERED

Dalbavancin safety and tolerability data from trials and post-marketing studies were reviewed. While most trials included predominantly ABSSSI, 2 clinical trials and recent observational studies have explored the use of dalbavancin for off-label indications, mainly including bloodstream and osteoarticular infections.

EXPERT OPINION

The occurrence of drug-related adverse effects (AE) was similar between dalbavancin and comparators in clinical trials enrolling patients with ABSSSI. Most common AE included gastrointestinal symptoms, infusion reaction, and hypersensitivity. Low rates of drug discontinuation and serious AE were reported across studies. In the past 5 years, several observational studies have reported safety data on the use of dalbavancin, confirming its favorable safety profile. Nevertheless, data from dalbavancin off-label use often derived from prolonged (> 2 weeks) treatments with variable dosing regimens, were mainly retrospective, and lacked comparators. Further research is required to allow a reliable analysis of short- and long-term dalbavancin-related AE in non-ABSSSI.

Clinical Effectiveness and Pharmacokinetics of Dalbavancin in Treatment-Experienced Patients with Skin, Osteoarticular, or Vascular Infections

Dalbavancin (DBV) is a lipoglycopeptide approved for the treatment of Gram-positive infections of the skin and skin-associated structures (ABSSSIs). Currently, its off-label use at different dosages for other infections deserves attention. This work aimed to study the clinical effectiveness and tolerability of DBV in outpatients with ABSSSIs, osteoarticular (OA), or other infections, treated with either one or two 1500 mg doses of dalbavancin, for different scheduled periods. A liquid chromatography–tandem mass spectrometry method was used to measure total DBV concentrations. PK/PD parameters and the clinical and microbiological features of this cohort were evaluated in order to investigate the best predictors of treatment success in real-life settings. Of the 76 screened patients, 41 completed the PK study. Long-term PK was comparable to previous studies and showed significant differences between genders and dosing schedules. Few adverse events were observed, and treatment success was achieved in the vast majority of patients. Failure was associated with lower PK parameters, particularly C_max. Concluding, we were able to describe DBV PK and predictors of treatment success in selected infections in this cohort, finding DBV C_max as a possible candidate for therapeutic drug-monitoring purposes, as well as highlighting the dual-dose one-week-apart treatment as the optimal choice for OA infections.

Population Pharmacokinetic and Pharmacodynamic Analysis of Dalbavancin for Long-Term Treatment of Subacute and/or Chronic Infectious Diseases: The Major Role of Therapeutic Drug Monitoring

A population pharmacokinetic analysis of dalbavancin was conducted in patients with different infection sites. Non-linear mixed effect modeling was used for pharmacokinetic analysis and covariate evaluation. Monte Carlo simulations assessed the probability of target attainment (PTA) of total dalbavancin concentration ≥ 8.04 mg/L over time (associated with ≥90% probability of optimal pharmacodynamic target attainment of fAUC24h/MIC > 111.1 against S. aureus) associated with a single or double dosage, one week apart, of 1000 or 1500 mg in patients with different classes of renal function. Sixty-nine patients with 289 concentrations were included. Most of them (53/69, 76.8%) had bone and joint infections. A two-compartment model adequately fitted dalbavancin concentration−time data. Creatinine clearance (CLCR) was the only covariate associated with dalbavancin clearance. Monte Carlo simulations showed that, in patients with severe renal dysfunction, the 1000 mg single or double one week apart dosage may ensure optimal PTAs of 2 and 5 weeks, respectively. In patients with preserved renal function, the 1500 mg single or double one-week apart dosage may ensure optimal PTAs of 2 and 4 to 6 weeks, respectively. Therapeutic drug monitoring should be considered mandatory for managing inter-individual variability and for supporting clinicians in long-term treatments of subacute and chronic infections.

Comparison of Sequential Dalbavancin to Standard-of-Care Treatment for Staphylococcus aureus Bloodstream Infections

Background

Dalbavancin (DAL) is a long-acting lipoglycopeptide with activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). This study investigates DAL as sequential therapy in S. aureus bloodstream infections (BSIs).

Methods

We conducted a retrospective cohort study from 2014 to 2021 comparing sequential DAL with standard-of-care therapy (SoC) for S. aureus BSI. The primary outcome was 90-day clinical failure (90-day all-cause mortality or 90-day recurrence). Secondary outcomes were incidence of acute kidney injury, creatinine phosphokinase elevations, catheter-related thrombosis, and hospital-acquired infections. Analyses were adjusted using inverse probability of treatment weighting (IPTW).

Results

Overall, 225 patients (45 DAL, 180 SoC) were included. DAL patients had a higher incidence of community-acquired infection and persons who use drugs; SoC patients had more comorbidities and a longer duration of bacteremia. MRSA incidence was similar between the DAL and SoC groups. The median length of stay was 16 days among DAL recipients compared with 24 days among SoC recipients. Central catheter placement was 17.8% compared with 57.2% in the SoC group. Ninety-day clinical failure occurred in 13.3% and 18.3% of participants in the DAL and SOC groups, respectively. In IPTW-adjusted analysis, sequential DAL was not associated with 90-day clinical failure (adjusted odds ratio, 0.94; 95% CI, 0.333–2.32).

Conclusions

This study provides preliminary evidence that select patients with S. aureus BSI treated with sequential DAL have similar clinical failure rates, with significant reductions in catheter placement and hospital length of stay compared with SoC. Further prospective evaluation is needed.