Dalbavancin as an option for treatment of S. aureus bacteremia (DOTS): study protocol for a phase 2b, multicenter, randomized, open-label clinical trial

How I manage severe bacterial infections in people who inject drugs

BACKGROUND

Injecting drug use is a risk factor for severe bacterial infection, but there is limited high-quality evidence to guide clinicians providing care to people who inject drugs. Management can be complicated by mistrust, stigma, and competing patient priorities.

OBJECTIVES

To review the management of severe infections in people who inject drugs, using an illustrative clinical scenario of complicated Staphylococcus aureus bloodstream infection.

SOURCES

The discussion is based on recent literature searches of relevant topics. Very few randomized clinical trials have focussed specifically on the management of severe bacterial infections among people who inject drugs. Most recommendations are, therefore, based on observational studies, extrapolation from other patient groups, and the experience and opinions of the authors.

CONTENT

We discuss evidence and options regarding the following management issues for severe bacterial infections among people who inject drugs: initial management of sepsis; indications for surgical management; assessment and management of substance dependence; approaches to antibiotic administration following clinical stability; opportunistic health promotion; and secondary prevention of bacterial infections. Throughout, we highlight the importance of harm reduction and strategies to optimize patient engagement in care through a patient-centred approach.

IMPLICATIONS

We advocate for a multi-disciplinary trauma-informed approach to the management of severe bacterial infection among people who inject drugs. We emphasize the need for pragmatic trials to inform management guidelines, including those that are co-designed with the community. In particular, research is needed to establish the comparative effectiveness, safety, and cost-effectiveness of inpatient intravenous antibiotics vs. early oral antibiotic switch, outpatient parenteral therapy, and long-acting lipoglycopeptide antibiotics in this scenario.

Finding value in novel antibiotics: How can infectious diseases adopt incremental cost-effectiveness to improve new antibiotic utilization?

Research and development of innovative antimicrobials is paramount to addressing the antimicrobial resistance threat. Although antimicrobial discovery and development has increased, difficulties have emerged in the pharmaceutical industry after market approval. In this minireview, we summarize clinical trial data on recently approved antibiotics, calculate incremental cost-effectiveness ratio (ICER) values, and explore ways to adapt ICER calculations to the limitations of antimicrobial clinical trial design. We provide a systematic review and analysis of randomized, controlled studies of antibiotics approved from 2014 - 2022 and extracted the relevant clinical data. Adapted-ICER (aICER) calculations were conducted using the primary condition-specific outcome that was reported in each study (percent mortality or percent cure rate). The literature search identified 18 studies for the 8 total antibiotics which met inclusion criteria and contained data required for aICER calculation. aICER values ranged from -$17,374 to $4,966 per percent mortality and -$43,931 to $2,529 per percent cure rate. With regards to mortality, ceftolozane/tazobactam and imipenem/cilastatin/relebactam proved cost efficacious, with aICER values of $4,965 per percent mortality and $1,955 per percent mortality respectively. Finding value in novel antibiotic agents is imperative to further justifying their development, and aICER values are the most common method of determining value in healthcare. The current outcomes of clinical trials are difficult to translate to aICER, which most effectively use Quality-Adjusted Life Years (QALY) as the quality standard in other fields such as oncology. Future antimicrobial trials should consider introducing methods of assessing measures of health gain such as QALY to better translate the value of novel antimicrobials in healthcare.

Combination of Antistaphylococcal β-Lactam With Standard Therapy Compared to Standard Therapy Alone for the Treatment of Methicillin-Resistant Staphylococcus aureus Bacteremia: A Post Hoc Analysis of the CAMERA2 Trial Using a Desirability of Outcome Ranking Approach

Background

Desirability of outcome ranking (DOOR) is an emerging approach to clinical trial outcome measurement using an ordinal scale to incorporate efficacy and safety endpoints.

Methods

We applied a previously validated DOOR endpoint to a cohort of CAMERA2 trial participants with methicillin-resistant Staphylococcus aureus bacteremia (MRSAB). Participants were randomly assigned to standard therapy, or to standard therapy plus an antistaphylococcal β-lactam (combination therapy). Each participant was assigned a DOOR category, within which they were further ranked according to their hospital length of stay (LOS) and duration of intravenous antibiotic treatment. We calculated the probability and the generalized odds ratio of participants receiving combination therapy having worse outcomes than those receiving standard therapy.

Results

Participants assigned combination therapy had a 54.5% (95% confidence interval [CI], 48.9%-60.1%; P = .11) probability and a 1.2-fold odds (95% CI, .95-1.50; P = .12) of having a worse outcome than participants on standard therapy. When further ranked according to LOS and duration of antibiotic treatment, participants in the combination group had a 55.6% (95% CI, 49.5%-61.7%) and 55.3% (95% CI, 49.2%-61.4%) probability of having a worse outcome than participants in the standard treatment group, respectively.

Conclusions

When considering both efficacy and safety, treatment of MRSAB with a combination of standard therapy and a β-lactam likely results in a worse clinical outcome than standard therapy. However, a small benefit of combination therapy cannot be excluded. Most likely the toxicity of combination therapy outweighed any benefit from faster clearance of bacteremia.

Real-World Dalbavancin Use for Serious Gram-Positive Infections: Comparing Outcomes Between People Who Use and Do Not Use Drugs

Background

Dalbavancin has been used off-label to treat invasive bacterial infections in vulnerable populations like people who use drugs (PWUD) because of its broad gram-positive coverage and unique pharmacological properties. This retrospective, multisite study examined clinical outcomes at 90 days in PWUD versus non-PWUD after secondary treatment with dalbavancin for bacteremia, endocarditis, osteomyelitis, septic arthritis, and epidural abscesses.

Methods

Patients at 3 teaching hospitals who received dalbavancin for an invasive infection between March 2016 and May 2022 were included. Characteristics of PWUD and non-PWUD, infection highlights, hospital stay and treatment, and outcomes were compared using χ2 for categorical variables, t test for continuous variables, and nonparametric tests where appropriate.

Results

There were a total of 176 patients; 78 were PWUD and 98 were non-PWUD. PWUD were more likely to have a patient-directed discharge (26.9% vs 3.1%; P < .001) and be lost to follow-up (20.5% vs 7.14%; P < .01). Assuming loss to follow-up did not achieve clinical cure, 73.1% of PWUD and 74.5% of non-PWUD achieved clinical cure at 90 days (P = .08).

Conclusions

Dalbavancin was an effective treatment option for invasive gram-positive infections in our patient population. Despite higher rates of patient-directed discharge and loss to follow-up, PWUD had similar rates of clinical cure at 90 days compared to non-PWUD.

Dalbavancin Sequential Therapy for Gram-Positive Bloodstream Infection: A Multicenter Observational Study

INTRODUCTION

Long-acting lipoglycopeptides such as dalbavancin may have utility in patients with Gram-positive bloodstream infections (BSI), particularly in those with barriers to discharge or who require prolonged parenteral antibiotic courses. A retrospective cohort study was performed to provide further multicenter real-world evidence on dalbavancin use as a sequential therapy for Gram-positive BSI.

METHODS

One hundred fifteen patients received dalbavancin with Gram-positive BSI, defined as any positive blood culture or diagnosed with infective endocarditis, from 13 centers geographically spread across the United States between July 2015 and July 2021.

RESULTS

Patients had a mean (SD) age of 48.5 (17.5) years, the majority were male (54%), with many who injected drugs (40%). The most common infection sources (non-exclusive) were primary BSI (89%), skin and soft tissue infection (SSTI) (25%), infective endocarditis (19%), and bone and joint infection (17%). Staphylococcus aureus accounted for 72% of index cultures, coagulase-negative Staphylococcus accounted for 18%, and Streptococcus species in 16%. Dalbavancin started a median (Q1-Q3) of 10 (6-19) days after index culture collection. The most common regimen administered was dalbavancin 1500 mg as one dose for 50% of cases. The primary outcome of composite clinical failure occurred at 12.2%, with 90-day mortality at 7.0% and 90-day BSI recurrence at 3.5%.

CONCLUSIONS

Dalbavancin may serve as a useful tool in facilitating hospital discharge in patients with Gram-positive BSI. Randomized controlled trials are anticipated to validate dalbavancin as a surrogate to current treatment standards.

Application of desirability of outcome ranking to the milking in non-vigorous infants trial

OBJECTIVES

Neonatal trials have traditionally used binary composite short-term (such as death or bronchopulmonary dysplasia) or longer-term (such as death or severe neurodevelopmental impairment) outcomes. We applied the Desirability Of Outcome Ranking (DOOR) method to rank the overall patient outcome by best (no morbidities) to worst (death).

STUDY DESIGN

Using a completed large multicenter trial (Milking In Non-Vigorous Infants [MINVI]) of umbilical cord milking (UCM) vs. early cord clamping (ECC), we applied the DOOR methodology to neonatal outcomes. Six outcomes were chosen and ranked: no interventions or NICU admission (most desirable); received initial cardiorespiratory support at birth; neonatal intensive care unit (NICU) admission for predefined criteria; mild hypoxic-ischemic encephalopathy (HIE); moderate to severe HIE; and death (least desirable).

RESULTS

1524 non-vigorous newborns born between 35 and 42 weeks' gestation had data for analysis. The DOOR distribution was different between the UCM and ECC arms, with a significantly greater probability (55.8 % [95 % CI 53.1-58.5 %; p < 0.0001]) of a randomly selected neonate having a more desirable outcome if they were in the UCM arm. DOOR probabilities of averting individual adverse outcomes such as NICU admission for predefined criteria (52.8 %; 95%CI 50.5-55.1 %) and cardiorespiratory support (54.0 %; 95%CI 51.6-56.4 %) were significantly higher among those in the UCM group.

CONCLUSION

DOOR provides an overall assessment of the benefits and harms with greater insight than typical binary composite measures to clinicians and parents when evaluating an intervention. Future neonatal trials should consider the a priori use of the DOOR methodology to evaluate trial outcomes.

Comparison of dalbavancin with standard of care in the management of infective endocarditis: efficacy, safety, and cost analysis

OBJECTIVES

Due to its long half-life, dalbavancin offers benefits for long-duration treatments, especially osteoarticular and infective endocarditis (IE). We evaluated the efficacy and costs of IE treatment, comparing dalbavancin with standard of care (SOC).

METHODS

Retrospective multicenter cohort study of adult patients with Gram-positive cocci definite IE. Dalbavancin was used as a sequential therapy before discharge. Efficacy was a combined variable of clinical cure and absence of recurrence in 12-month follow-up. Length of hospital stay and the associated costs were analyzed in both groups of treatment.

RESULTS

Twenty-two patients received dalbavancin and 47 SOC. The efficacy was similar between the groups (dalbavancin 18 [72%] vs SOC 44 [94%], P = 0.198). Hospital stay was shorter in the dalbavancin group (dalbavancin 22 days [16-34] vs SOC 37 days [23-49], P = 0.001), especially in those with E. faecalis IE (dalbavancin 30 days [20-36] vs SOC 65 days [46-74], P <0.001). A reduction of cost was observed between both groups (dalbavancin, 12,206 € [8998-17,283] vs SOC 16,249 € [11,496-22,367], P = 0.032).

CONCLUSION

Dalbavancin could be a safe and effective option in the sequential treatment of patients with IE. Also, a cost reduction was detected, due to a significant shortness of hospital stay.

Dalbavancin as an alternative to traditional outpatient parenteral antimicrobial therapy for deep gram-positive infections - an observational, retrospective review

Background

Treatment of invasive gram-positive infections in complex patient populations is challenging. Dalbavancin, approved for skin and soft tissue infections, offers advantages in this setting due to its long half-life and infrequent dosing. However, less is known about the outcomes of off-label dalbavancin for deeper infections.

Objectives

The objective of this study is to examine the feasibility and outcomes of patients with complex gram-positive infections treated with dalbavancin as an alternative to standard outpatient parenteral antimicrobial therapy (OPAT).

Methods

We conducted a multicenter, retrospective review of adult patients managed within an OPAT program with intravenous dalbavancin for off-label indications. Adult patients were included if they had treatment details and follow-up documented between January 2020 and June 2023. Details of dalbavancin use including indications for prescription were captured. Outcomes of interest included 90-day infection recurrence, prosthesis retention rates, 90-day mortality, and adverse medication events.

Results

In all, 61 patients received dalbavancin, mostly as sequential therapy. Twenty-three percent received dalbavancin strictly in the outpatient setting. Dalbavancin was used primarily for hardware (fracture, spine, or joint), native bone or joint, and complicated soft tissue infections. The predominant pathogen was Staphylococcus aureus (61%). Dalbavancin was frequently prescribed as a two-dose 1500 mg regimen (49%) due to persistent infection (23%), difficult line access (30%), difficulty achieving therapeutic vancomycin levels (18%), or substance abuse history (18%). Overall, six patients (10%) had infection recurrence and no patients died during the follow-up period. Three of eight patients with hardware retention had infection recurrence. Adverse effects were minimal and mostly self-limiting.

Conclusion

Dalbavancin is an efficacious and safe alternative to standard OPAT, especially in those with barriers to traditional long-term intravenous antibiotics. Improved outcomes may be achieved with hardware removal. Dalbavancin may facilitate early discharge or prevent hospitalizations. Comparative studies of standard OPAT regimens versus dalbavancin are needed.

Novel drug candidates against antibiotic-resistant microorganisms: A review

Antibiotic resistance is fast spreading globally, leading to treatment failures and adverse clinical outcomes. This review focuses on the resistance mechanisms of the top five threatening pathogens identified by the World Health Organization's global priority pathogens list: carbapenem-resistant Acinetobacter baumannii, carbapenem-resistant Pseudomonas aeruginosa, carbapenem-resistant, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, vancomycin-resistant Enterococcus faecium and methicillin, vancomycin-resistant Staphylococcus aureus. Several novel drug candidates have shown promising results from in vitro and in vivo studies, as well as clinical trials. The novel drugs against carbapenem-resistant bacteria include LCB10-0200, apramycin, and eravacycline, while for Enterobacteriaceae, the drug candidates are LysSAP-26, DDS-04, SPR-206, nitroxoline, cefiderocol, and plazomicin. TNP-209, KBP-7072, and CRS3123 are agents against E. faecium, while Debio 1450, gepotidacin, delafloxacin, and dalbavancin are drugs against antibiotic-resistant S. aureus. In addition to these identified drug candidates, continued in vitro and in vivo studies are required to investigate small molecules with potential antibacterial effects screened by computational receptor docking. As drug discovery progresses, preclinical and clinical studies should also be extensively conducted on the currently available therapeutic agents to unravel their potential antibacterial effect and spectrum of activity, as well as safety and efficacy profiles.

Contemporary Management of Staphylococcus aureus Bacteremia-Controversies in Clinical Practice

Staphylococcus aureus bacteremia (SAB) carries a high risk for excess morbidity and mortality. Despite its prevalence, significant practice variation continues to permeate clinical management of this syndrome. Since the publication of the 2011 Infectious Diseases Society of America (IDSA) guidelines on management of methicillin-resistant Staphylococcus aureus infections, the field of SAB has evolved with the emergence of newer diagnostic strategies and therapeutic options. In this review, we seek to provide a comprehensive overview of the evaluation and management of SAB, with special focus on areas where the highest level of evidence is lacking to inform best practices.

The Future Ain't What It Used to Be…Out With the Old…In With the Better: Antibacterial Resistance Leadership Group Innovations

Clinical research networks conduct important studies that would not otherwise be performed by other entities. In the case of the Antibacterial Resistance Leadership Group (ARLG), such studies include diagnostic studies using master protocols, controlled phage intervention trials, and studies that evaluate treatment strategies or dynamic interventions, such as sequences of empiric and definitive therapies. However, the value of a clinical research network lies not only in the results from these important studies but in the creation of new approaches derived from collaborative thinking, carefully examining and defining the most important research questions for clinical practice, recognizing and addressing common but suboptimal approaches, and anticipating that the standard approaches of today may be insufficient for tomorrow. This results in the development and implementation of new methodologies and tools for the design, conduct, analyses, and reporting of research studies. These new methodologies directly impact the studies conducted within the network and have a broad and long-lasting impact on the field, enhancing the scientific value and efficiency of generations of research studies. This article describes innovations from the ARLG in diagnostic studies, observational studies, and clinical trials evaluating interventions for the prevention and treatment of antibiotic-resistant bacterial infections.

The Antibacterial Resistance Leadership Group: Scientific Advancements and Future Directions

In this overview, we describe important contributions from the Antibacterial Resistance Leadership Group (ARLG) to patient care, clinical trials design, and mentorship while outlining future priorities. The ARLG research agenda is focused on 3 key areas: gram-positive infections, gram-negative infections, and diagnostics. The ARLG has developed an innovative approach to clinical trials design, the desirability of outcome ranking (DOOR), which uses an ordinal measure of global outcome to assess both benefits and harms. DOOR was initially applied to observational studies to determine optimal dosing of vancomycin for methicillin-resistant Staphylcococcus aureus bacteremia and the efficacy of ceftazidime-avibactam versus colistin for the treatment of carbapenem-resistant Enterobacterales infection. DOOR is being successfully applied to the analysis of interventional trials and, in collaboration with the US Food and Drug Administration (FDA), for use in registrational trials. In the area of diagnostics, the ARLG developed Master Protocol for Evaluating Multiple Infection Diagnostics (MASTERMIND), an innovative design that allows simultaneous testing of multiple diagnostic platforms in a single study. This approach will be used to compare molecular assays for the identification of fluoroquinolone-resistant Neisseria gonorrhoeae (MASTER GC) and to compare rapid diagnostic tests for bloodstream infections. The ARLG has initiated a first-in-kind randomized, double-blind, placebo-controlled trial in participants with cystic fibrosis who are chronically colonized with Pseudomonas aeruginosa to assess the pharmacokinetics and antimicrobial activity of bacteriophage therapy. Finally, an engaged and highly trained workforce is critical for continued and future success against antimicrobial drug resistance. Thus, the ARLG has developed a robust mentoring program targeted to each stage of research training to attract and retain investigators in the field of antimicrobial resistance research.

Priorities and Progress in Gram-positive Bacterial Infection Research by the Antibacterial Resistance Leadership Group: A Narrative Review

The Antibacterial Resistance Leadership Group (ARLG) has prioritized infections caused by gram-positive bacteria as one of its core areas of emphasis. The ARLG Gram-positive Committee has focused on studies responding to 3 main identified research priorities: (1) investigation of strategies or therapies for infections predominantly caused by gram-positive bacteria, (2) evaluation of the efficacy of novel agents for infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci, and (3) optimization of dosing and duration of antimicrobial agents for gram-positive infections. Herein, we summarize ARLG accomplishments in gram-positive bacterial infection research, including studies aiming to (1) inform optimal vancomycin dosing, (2) determine the role of dalbavancin in MRSA bloodstream infection, (3) characterize enterococcal bloodstream infections, (4) demonstrate the benefits of short-course therapy for pediatric community-acquired pneumonia, (5) develop quality of life measures for use in clinical trials, and (6) advance understanding of the microbiome. Future studies will incorporate innovative methodologies with a focus on interventional clinical trials that have the potential to change clinical practice for difficult-to-treat infections, such as MRSA bloodstream infections.

Under the Hood: The Scientific Leadership, Clinical Operations, Statistical and Data Management, and Laboratory Centers of the Antibacterial Resistance Leadership Group

Developing and implementing the scientific agenda of the Antibacterial Resistance Leadership Group (ARLG) by soliciting input and proposals, transforming concepts into clinical trials, conducting those trials, and translating trial data analyses into actionable information for infectious disease clinical practice is the collective role of the Scientific Leadership Center, Clinical Operations Center, Statistical and Data Management Center, and Laboratory Center of the ARLG. These activities include shepherding concept proposal applications through peer review; identifying, qualifying, training, and overseeing clinical trials sites; recommending, developing, performing, and evaluating laboratory assays in support of clinical trials; and designing and performing data collection and statistical analyses. This article describes key components involved in realizing the ARLG scientific agenda through the activities of the ARLG centers.

Contemporary pharmacologic treatments of MRSA for hospitalized adults: rationale for vancomycin versus non-vancomycin therapies as first line agents

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) remains an important pathogen in the hospital setting and causes significant morbidity and mortality each year. Since the initial discovery over 60 years ago, vancomycin has remained a first-line treatment for many different types of MRSA infections. However, significant concerns related to target attainment and nephrotoxicity have spurred efforts to develop more effective agents in the last two decades.

AREAS COVERED

Newer anti-MRSA antibiotics that have been approved since 2000 include linezolid, daptomycin, and ceftaroline. As clinical evidence has accumulated, these newer agents have become more frequently used, and some are now recommended as co-first-line options (along with vancomycin) in clinical practice guidelines. For this review, a scoping review of the literature was conducted to support our findings and recommendations.

EXPERT OPINION

Vancomycin remains an important standard of care for MRSA infections but is limited with respect to nephrotoxicity and rapid target attainment. Newer agents such as linezolid, daptomycin, and ceftaroline have specific indications for treating different types of MRSA infections; however, newer agents also have unique attributes which require consideration during therapy.

Unlocking the DOOR - how to design, apply, analyse, and interpret desirability of outcome ranking (DOOR) endpoints in infectious diseases clinical trials

BACKGROUND

Desirability of outcome ranking (DOOR) outcomes, with or without response adjusted for antibiotic risk (RADAR), are increasingly used in infectious diseases randomized clinical trials (RCTs), with the advantage of being able to combine multiple clinical outcomes and antibiotic duration in a single metric. However, it remains poorly understood, and there is considerable heterogeneity in its use.

OBJECTIVES

In this scoping review, we explain how to design, use, and analyse a DOOR endpoint, and highlight several pitfalls and potential improvements that can be made to DOOR/RADAR.

SOURCES

The Ovid MEDLINE database was searched for terms related to DOOR in English-language papers published up to 31 December 2022. Papers discussing DOOR methodology and/or reporting clinical trial analyses (as either primary, secondary, or post-hoc analysis) using a DOOR outcome were included.

CONTENT

17 papers were included in the final review, of which 9 reported DOOR analyses of 12 RCTs. 8 papers discussed DOOR methodology. We synthesised information from these papers and discuss (a) How to develop a DOOR scale, (b) How to conduct a DOOR/RADAR analysis, (c) Use in clinical trials, (d) Use of alternative tiebreakers apart from RADAR, (e) Partial credit analyses, and (f) Criticisms and pitfalls of DOOR/RADAR.

IMPLICATIONS

DOOR is an important innovation for RCTs in infectious diseases. We highlight potential areas of methodological improvement for future research. There remains considerable heterogeneity in its implementation, and further collaborative efforts, with a more diverse range of perspectives, should be made to develop consensus scales for use in prospective studies.

REFINE-Lung implements a novel multi-arm randomised trial design to address possible immunotherapy overtreatment

Increasing evidence suggests that some immunotherapy dosing regimens for patients with advanced cancer could result in overtreatment. Given the high costs of these agents, and important implications for quality of life and toxicity, new approaches are needed to identify and reduce unnecessary treatment. Conventional two-arm non-inferiority designs are inefficient in this context because they require large numbers of patients to explore a single alternative to the standard of care. Here, we discuss the potential problem of overtreatment with anti-PD-1 directed agents in general and introduce REFINE-Lung (NCT05085028), a UK multicentre phase 3 study of reduced frequency pembrolizumab in advanced non-small-cell lung cancer. REFINE-Lung uses a novel multi-arm multi-stage response over continuous interventions (MAMS-ROCI) design to determine the optimal dose frequency of pembrolizumab. Along with a similarly designed basket study of patients with renal cancer and melanoma, REFINE-Lung and the MAMS-ROCI design could contribute to practice-changing advances in patient care and form a template for future immunotherapy optimisation studies across cancer types and indications. This new trial design is applicable to many new or existing agents for which optimisation of dose, frequency, or duration of therapy is desirable.

Clinical Impact of Staphylococcus aureus Skin and Soft Tissue Infections

The pathogenic bacterium Staphylococcus aureus is the most common pathogen isolated in skin-and-soft-tissue infections (SSTIs) in the United States. Most S. aureus SSTIs are caused by the epidemic clone USA300 in the USA. These infections can be serious; in 2019, SSTIs with S. aureus were associated with an all-cause, age-standardized mortality rate of 0.5 globally. Clinical presentations of S. aureus SSTIs vary from superficial infections with local symptoms to monomicrobial necrotizing fasciitis, which can cause systemic manifestations and may lead to serious complications or death. In order to cause skin infections, S. aureus employs a host of virulence factors including cytolytic proteins, superantigenic factors, cell wall-anchored proteins, and molecules used for immune evasion. The immune response to S. aureus SSTIs involves initial responders such as keratinocytes and neutrophils, which are supported by dendritic cells and T-lymphocytes later during infection. Treatment for S. aureus SSTIs is usually oral therapy, with parenteral therapy reserved for severe presentations; it ranges from cephalosporins and penicillin agents such as oxacillin, which is generally used for methicillin-sensitive S. aureus (MSSA), to vancomycin for methicillin-resistant S. aureus (MRSA). Treatment challenges include adverse effects, risk for Clostridioides difficile infection, and potential for antibiotic resistance.

Persistent Methicillin-Resistant Staphylococcus aureus Bacteremia: Host, Pathogen, and Treatment

Methicillin-resistant Staphylococcus aureus (MRSA) is a devastating pathogen responsible for a variety of life-threatening infections. A distinctive characteristic of this pathogen is its ability to persist in the bloodstream for several days despite seemingly appropriate antibiotics. Persistent MRSA bacteremia is common and is associated with poor clinical outcomes. The etiology of persistent MRSA bacteremia is a result of the complex interplay between the host, the pathogen, and the antibiotic used to treat the infection. In this review, we explore the factors related to each component of the host-pathogen interaction and discuss the clinical relevance of each element. Next, we discuss the treatment options and diagnostic approaches for the management of persistent MRSA bacteremia.

The hidden cost of dalbavancin: OPAT RN time required in coordination for persons who use drugs

Background

Serious infections in persons who use drugs (PWUD) are rising. Dalbavancin, due to its extended half-life, offers an alternative treatment for patients in whom standard of care antibiotics are not feasible or practical, allowing for reduced hospital days and the avoidance of central line placement or the use of complex oral regimens.

Objectives

We aim to describe the time and effort required for coordination of dalbavancin courses by outpatient registered nurses (RNs) and other outpatient parenteral antimicrobial therapy (OPAT) staff.

Design and methods

We conducted a retrospective review of adult patients with documented substance use who received at least one dose of dalbavancin and quantified the number of interventions required by our OPAT RNs and other OPAT staff for coordination of dalbavancin courses. Additionally, detailed data on time spent per intervention were prospectively collected for a 1-month period.

Results

A total of 52 patients with 53 dalbavancin courses were included. Most substance use was intravenous. Infectious diagnoses included bone and joint infections (61%) and endocarditis (7%), in addition to skin and soft tissue infections (19%). Infections were most commonly caused by Staphylococcus aureus (62%). RN intervention was required in the coordination of 60% of all courses and in 77% of courses in which at least one outpatient dose was needed. Adverse reactions occurred in one patient (2%) and 90-day readmissions due to infectious complications occurred in two patients (4%). Detailed time analysis was performed for seven consecutive patients, with a total of 179 min spent by OPAT RNs on coordination.

Conclusions

The ease of dalbavancin administration does not eliminate the need for extensive RN coordination for successful administration of doses in the outpatient setting for PWUD. This need should be accounted for in program staffing to help increase successful dalbavancin course completion.