A Randomized Clinical Trial of Single-Dose Versus Weekly Dalbavancin for Treatment of Acute Bacterial Skin and Skin Structure Infection

Dalbavancin Population Pharmacokinetic Modeling and Target Attainment Analysis

Dalbavancin is indicated for the treatment of acute bacterial skin and skin structure infections caused by susceptible gram-positive microorganisms. This analysis represents the update of the population pharmacokinetics (popPK) modeling and target attainment simulations performed with data from the single-dose safety and efficacy study and an unrelated but substantial revision of the preclinical pharmacokinetic/pharmacodynamic target (fAUC/MIC, free area under concentration-time curve/minimum inhibitory concentration ratio). A 3-compartment distribution model with first-order elimination provided an appropriate fit, with typical dalbavancin clearance of 0.05 L/h and total volume of distribution of ∼15 L. Impact of intrinsic factors was modest, although statistically significant (P < .05) relationships with total clearance were found for the following covariates: creatinine clearance, weight, and albumin - dose adjustment was only indicated for severe renal impairment. Under the new nonclinical target, simulations of the popPK model projected that >99% of subjects would achieve the nonclinical target at MIC values up to and including 2 mg/L.

Clinical experience with dalbavancin for the treatment of deep sternal wound infection

OBJECTIVES

Deep sternal wound infection (DSWI) is a complication of major heart surgery with high morbidity as well as prolonged antimicrobial treatment and hospital length of stay (LoS). Dalbavancin is a new lipoglycopeptide antibiotic active against Gram-positive micro-organisms, including methicillin-resistant Staphylococcus aureus (MRSA), with a long half-life. This small case series assessed the feasibility of dalbavancin for the treatment of DSWI.

METHODS

This was retrospective, observational, cohort study of patients treated with dalbavancin for DSWI over a 2-year period (March 2016 to April 2018) in two cardiac surgery departments in Italy. All patients with DSWI underwent surgical accurate debridement. Dalbavancin was administered during the hospital stay or in an outpatient facility.

RESULTS

Among 15 patients enrolled in the study, MRSA was isolated in 7 (47%), methicillin-resistant Staphylococcus epidermidis in 6 (40%) and other coagulase-negative staphylococci in 2 (13%). Dalbavancin was administered by two infusions in 9 patients (60%), whereas 5 patients (33%) received a median of four doses. Fourteen patients received a first dose of 1000mg followed by 500mg, whereas one patient received two doses of 1500mg each. All patients were defined as clinically cured. The median hospital LoS was 13 days (interquartile range, 8-18 days). At 6 months after discharge, 14 patients (93%) showed no relapse of DSWI, whereas 1 patient recurred with a diagnosis of DSWI caused by another pathogen (Candida sp.).

CONCLUSION

Dalbavancin may be an alternative option for DSWI caused by Gram-positive bacteria when first-line treatments are contraindicated or as salvage treatment.

Single-dose dalbavancin and patient satisfaction in an outpatient setting in the treatment of acute bacterial skin and skin structure infections

OBJECTIVES

Treatment of acute bacterial skin and skin structure infections (ABSSSIs) in the outpatient setting has potential advantages. We performed a subanalysis of outcomes for patients treated as outpatients versus inpatients with dalbavancin, a long-acting lipoglycopeptide, in a phase 3 clinical trial of ABSSSI.

METHODS

The study was a double-blind trial of patients with ABSSSI randomised to receive dalbavancin 1500 mg intravenously as a single dose or two doses (1000 mg followed by 500 mg a week later). The primary endpoint was ≥20% reduction in erythema at 48-72 h after the start of therapy. Patient satisfaction and preference for antibiotic treatment and care setting were measured using the 10-item Skin and Soft Tissue Infection (SSTI) questionnaire at Day 14.

RESULTS

A total of 698 patients were randomised (386 treated as outpatients and 312 as inpatients). Outpatients were more likely to be younger and to have major abscess or traumatic wound infection; inpatients were more likely to have cellulitis as the type of ABSSSI, to meet SIRS criteria and to have elevated plasma lactate at baseline. Efficacy and safety outcomes at 48-72 h, Days 14 and 28 were similar between patients treated in the outpatient and inpatient setting with either the single-dose or two-dose regimen. Outpatients reported significantly greater convenience and satisfaction with antibiotic treatment and care setting compared with inpatients (P < 0.001).

CONCLUSION

Single-dose dalbavancin is an effective treatment option for outpatients with ABSSSI and is associated with a high degree of patient treatment satisfaction and convenience.

Multicenter clinical experience of real life Dalbavancin use in gram-positive infections

Dalbavancin, a lipoglycopeptide with prolonged half-life approved for the treatment of acute bacterial skin and soft tissue infections, can be used for the treatment of infections caused by gram-positive bacteria requiring long term treatment such as endocarditis, prosthetic joint infections (PJI) or osteomyelitis. Clinical data are limited in these settings.

OBJECTIVES

To evaluate indications, safety, tolerability and long-term outcomes of dalbavancin-treated patients. Patients and methods Our multicenter, retrospective study includes patients who received dalbavancin in Austria from September 2016 to March 2018. 90-day outcomes and tolerability were determined.

RESULTS

A total of 101 patients were included in 3 centers (57% male, median age 65 years). The treated infections were PJI (31%), osteomyelitis (29%), endocarditis (25%) and acute bacterial skin and soft tissue infections (12%). Concomitant use of other antimicrobial substances was common (63%). The mean total cumulative dose of dalbavancin was 3,357mg (±2,283mg). Clinical success rate was 89%. Side effects occurred in 3/101 patients.

CONCLUSION

In this real-life study dalbavancin was primarily used in off-label indications for treatment of PJI, osteomyelitis and endocarditis. Success rate was high (89%), tolerability and safety were excellent in this setting. Dalbavancin may therefore be used in these off-label indications as alternative treatment approach.

Prevention and Treatment of Multidrug-Resistant Organisms in End-Stage Renal Disease

Chronic kidney disease patients are at high risk for infections because of multidrug-resistant organisms. Infections are the second most common cause of death in patients with ESRD. Patients with ESRD are prone to infections given alterations in immunity, increased rates of colonization with multidrug-resistant organisms, increased hospitalizations, and interactions with health care systems. Infections range from urinary tract infections, pneumonia, skin and soft tissue infections, central line-associated bloodstream infections to sepsis. A coordinated collaborative effort using a multipronged approach must be stressed to reduce the burden of infections. Preventive measures such as hand hygiene, antibiotic stewardship, immunizations, and minimizing central venous catheters are critical to curtail infections with multidrug-resistant organisms. Empirical and targeted treatment for multidrug-resistant organisms may require collaboration with infectious disease providers to improve outcomes in these serious infections. It is imperative to address multidrug-resistant organisms in ESRD patients at this juncture to improve medical outcomes now and for the future.

Efficacy of Dalbavancin and Telavancin in the Treatment of Acute Bacterial Skin and Skin Structure Infections

Objectives

Two glycopeptide analogues, such as dalbavancin and telavancin, with improved pharmacokinetic/pharmacodynamic parameters have been developed. These two glycopeptide analogues are approved by Food and Drug Administration (FDA) for treatment of various Gram-positive bacterial skin infections.

Materials and methods

We have conducted an open labelled prospective randomized study to compare the efficacy of these two drugs. A total of 200 patients diagnosed with acute bacterial skin and skin structure infections (ABSSSI) were recruited for the study. They were randomized to receive either a single dose of dalbavancin 1500 mg i.v (Group I) or telavancin 10 mg/kg intravenously (i.v.) every 24 hours for six days (Group II). The skin infection rating score (SIRS) was calculated on Day 0 for all patients at the time of diagnosis. Signs and symptoms of the lesions were assessed based on the following factors: blistering, exudate/pus, erythema/inflammation and itching/pain. Each factor was classified as one of the following: absent - 0, minimal - 1, moderate - 2 and severe - 3.

Results

Clinically successful treatment was defined as complete resolution of clinically meaningful signs and symptoms of infection, including SIRS score of 0. The outcome measure was the percentage of patients with SIRS score of 0 on day 7 (clinical success). The third most common diagnosis at baseline was impetigo (13% in both groups). Patients who received dalbavancin had a higher clinical success rate than those receiving telavancin.

Conclusion

Findings of the present study show that single i.v dose of dalbavancin is better than telavancin repeated doses in treatment of ABSSSI.

Treatment of acute bacterial skin and skin structure infection with single-dose dalbavancin in persons who inject drugs

Background

Persons who inject drugs (PWID) are at increased risk of acute bacterial skin and skin structure infections (ABSSSIs), a growing healthcare concern. Multiple medical, social, and economic issues, including adherence and comorbidities, complicate the medical care of the PWID population, adversely affecting patient outcomes.

Methods

We assessed demographics and outcomes for the PWID population in a double-blind trial of 698 patients randomized to dalbavancin 1500 mg as a single intravenous (IV) infusion or as a 2-dose regimen (1000 mg IV on day 1; 500 mg IV on day 8) for ABSSSI. The primary endpoint was ≥20% reduction in erythema at 48–72 hours in the intent-to-treat population; clinical status was also assessed at days 14 and 28.

Results

There were 212/698 (30.4%) patients with a history of injection drug use in this clinical trial. Dalbavancin efficacy was similar between the single- and 2-dose therapy groups in the PWID and non-PWID populations at all timepoints. Dalbavancin was well tolerated in the PWID population, with similar rates of adverse events as the non-PWID population.

Conclusion

Dalbavancin as a single-dose or 2-dose regimen had similar efficacy for the treatment of ABSSSI at all timepoints in the PWID and non-PWID populations. A single 30-minute IV infusion would eliminate the need for indwelling IV access. The convenience of a single dose supervised in a health setting may also optimize treatment adherence in the PWID population.

Dalbavancin for the Treatment of Osteomyelitis in Adult Patients: A Randomized Clinical Trial of Efficacy and Safety

Background

Osteomyelitis is a challenging infection that can involve 4-6 weeks of intravenous (IV) antibiotics. Dalbavancin, approved for acute bacterial skin and skin structure infections, has potent activity against gram-positive pathogens. This study assessed the efficacy and safety of dalbavancin as a 2-dose regimen for osteomyelitis.

Methods

This study was a randomized, open-label, comparator-controlled trial in adults with a first episode of osteomyelitis defined by clinical symptoms, radiologic findings, and elevated C-reactive protein. Patients were randomized 7:1 to dalbavancin (1500 mg IV on days 1 and 8) or standard of care (SOC) for osteomyelitis (oral or IV) per investigator judgment for 4-6 weeks. The primary endpoint was clinical response at day 42, defined as recovery without need for additional antibiotics in the clinically evaluable (CE) population. Clinical response was also assessed at day 21, 6 months, and 1 year.

Results

Eighty patients were randomized to dalbavancin (n = 70) or SOC (n = 10). All had baseline debridement; Staphylococcus aureus was the most common pathogen (60% of patients). Clinical cure at day 42 was seen in 65/67 (97%) and 7/8 (88%) patients in the dalbavancin group and SOC group in the CE population, respectively. Clinical response was similar in the dalbavancin group at day 21 (94%), 6 months, and 1 year (96%). Treatment-emergent adverse events occurred in 10 patients in the dalbavancin group; no patient discontinued treatment due to an adverse event.

Conclusions

A 2-dose regimen of weekly dalbavancin is effective and well tolerated for the treatment of osteomyelitis in adults.

Clinical Trials Registration

NCT02685033.

Patient preferences for treatment of acute bacterial skin and skin structure infections in the emergency department

Background

Limited research has assessed patient preferences for treatment disposition and antibiotic therapy of acute bacterial skin and skin structure infection (ABSSSI) in the emergency department (ED). Understanding patient preference for the treatment of ABSSSI may influence treatment selection and improve satisfaction.

Methods

A survey was conducted across 6 US hospital EDs. Patients with ABSSSI completed a baseline survey assessing preferences for antibiotic therapy (intravenous versus oral) and treatment location. A follow-up survey was conducted within 30–40 days after ED discharge to reassess preferences and determine satisfaction with care.

Results

A total of 94 patients completed both baseline and follow-up surveys. Sixty (63.8%) participants had a history of ABSSSI, and 69 (73.4%) were admitted to the hospital. Treatment at home was the most common preference reported on baseline and follow-up surveys. Patients with higher education were 82.2% less likely to prefer treatment in the hospital. Single dose intravenous therapy was the most commonly preferred antibiotic regimen on baseline and follow-up surveys (39.8 and 19.1%, respectively). Median satisfaction scores for care in the ED, hospital, home, and with overall antibiotic therapy were all 8 out of a maximum of 10.

Conclusions

In these patients, the most common preference was for outpatient care and single dose intravenous antibiotics. Patient characteristics including higher education, younger age, and current employment were associated with these preferences. Opportunities exist for improving ABSSSI care and satisfaction rates by engaging patients and offering multiple treatment choices.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3751-0) contains supplementary material, which is available to authorized users.

Dalbavancin is a novel antimicrobial against Gram-positive pathogens: clinical experience beyond labelled indications

Very limited labelled indications have been approved for the newer antimicrobials. Data on the clinical uses, efficacy and safety of dalbavancin are scarce, thus here we sought to describe our clinical experience. 16-month observational prospective study was performed. 19 (86%) were used under off-label indications. 10 (46%) for osteoarticular infections, 5 (23%) bloodstream infections and 3 (14%) endocarditis. To highlight, one patient received dalbavancin as long-term suppressive therapy. Most frequent use reasons were promptly hospital discharge, 11 (65%), and the presence of resistant organisms involving limited treatment options, 5 (23%). Successful outcome was observed in >95% of the patients and only 1 (4.5%) adverse event was reported. Further evidence beyond labelled indications is urgently needed. Despite the limitations, dalbavancin appears to be a safe and efficient option for adult patients who have tried and/or failed other therapies due to multidrug-resistant Gram-positive organisms.

Trends in NP and RN enrollment, graduation, and practice

The employment outlook for NPs is expected to continue its growth trend in the coming years. This article summarizes graduation and employment trends for nursing students and provides a synopsis of data from the Bureau of Labor Statistics about the growing demand for NPs and nurses. A brief overview of the history of recent workforce trends is also provided.

Variability in Emergency Medicine Provider Decisions on Hospital Admission and Antibiotic Treatment in a Survey Study for Acute Bacterial Skin and Skin Structure Infections: Opportunities for Antimicrobial Stewardship Education

Background

Acute bacterial skin and skin structure infections (ABSSSIs) are a frequent cause of emergency department (ED) visits. Providers in the ED have many decisions to make during the initial treatment of ABSSSI. There are limited data on the patient factors that influence these provider decisions.

Methods

An anonymous survey was administered to providers at 6 EDs across the United States. The survey presented patient cases with ABSSSIs ≥75 cm² and escalating clinical scenarios including relapse, controlled diabetes, and sepsis. For each case, participants were queried on their decision for admission vs discharge and antibiotic therapy (intravenous, oral, or both) and to rank the factors that influenced their antibiotic decision.

Results

The survey was completed by 130 providers. For simple ABSSSI, the majority of providers chose an oral antibiotic and discharged patients home. The presence of recurrence or controlled diabetes resulted in more variation in responses. Thirty-four (40%) and 51 (60%) providers chose intravenous followed by oral antibiotics and discharged the recurrence and diabetes cases, respectively. Presentation with sepsis resulted in initiation with intravenous antibiotics (122, 95.3%) and admission (125, 96.1%) in most responses.

Conclusions

Variability in responses to certain patient scenarios suggests opportunities for education of providers in the ED and the development of an ABSSSI clinical pathway to help guide treatment.

Attitudes of physicians from 10 European countries on adherence and how treatment modalities in ABSSSI affect adherence: results from a Delphi survey

To explore the attitudes of European physicians on adherence and how treatment modalities impact adherence in complicated forms of soft skin and skin structure infections, now referred as acute bacterial skin and skin structures infections (ABSSSI). After literature review, a questionnaire was prepared. Topics focused on (1) the importance of adherence, (2) the importance of administration regimen on adherence, (3) the importance of drug selection on adherence, (4) the importance of complexity on choice of drug for treatment, (5) the role of adherence in drug resistance, and (6) the role of adherence in administration of long-acting antibiotics (ABs). The questionnaire was administered to 323 European infectious diseases specialists, of whom 74% responded. A modified Delphi method was used to obtain the highest consensus. Results varied by countries. We found a high degree of agreement of the importance of adherence in ABSSSI treatment. Experts agreed that complexity of patient’s conditions, drug selection, drug resistance, the type of regimen, and the number of infusions impact adherence. Two items linking oral switching and adherence did not reach consensus. Adherence for ABSSSI therapies appears a crucial factor for therapeutic management and reduces the risk of AB resistance. Among new treatment opportunities, long-acting agents, with their characteristics, may represent an interesting options.

Optimizing skin and skin structure infection outcomes: considerations of cost of care

INTRODUCTION

Skin and skin structure infections (SSSIs) refer to a collection of clinical infectious syndromes involving layers of skin and associated soft tissues. Although associated with less morbidity and mortality than other common skin infections, SSSIs represent a significant increasing source of healthcare expense, with a prevalence of 500 episodes per 10,000 patient-years in the United States resulting in burdening health care systems, of approximately $6 billion annually.

AREAS COVERED

Opportunities to reduce costs of care associated with SSSI are highlighted, including transitions of care and avoiding unnecessary hospital admissions. Moreover, we reviewed new antibiotics (e.g. single dose glycopeptides), and the impact of consulting specialists in the emergency department on SSSI treatment outcomes.

EXPERT COMMENTARY

New healthcare models and payment strategies combined with new therapeutics are challenging norms of care. Newer drugs to treat skin infections can move a substantive percent of patients previously admitted to hospital care to the outpatient setting. Additionally, patients can be managed with oral or one time intravenous regimens, improving the likelihood of patient adherence and satisfaction. These variables need to be weighed against added acquisition costs and the development of thoughtful algorithms is needed to direct care and optimize treatment, cost, and patient satisfaction.

A cost-minimization analysis of dalbavancin compared to conventional therapy for the outpatient treatment of acute bacterial skin and skin-structure infections

INTRODUCTION

Acute bacterial skin and skin-structure infections (ABSSSI) are common infectious diseases (ID) that often require intravenous (IV) antibiotics. Dalbavancin is a novel lipoglycopeptide antibiotic administered once that is FDA-approved for the treatment of ABSSSI. No literature is available for real-world cost-comparability relative to conventional therapy.

METHODS

This retrospective chart review examined adults diagnosed with ABSSSI and treated with IV antibiotics at an outpatient ID clinic after hospital discharge from January 2015 to August 2016. Patients received either dalbavancin or conventional therapy. In-hospital baseline demographics as well as outpatient clinical variables and outcomes were assessed. The primary outcome was the total ID-related cost of care per patient. A Monte Carlo probalistic sensitivity analysis was conducted.

RESULTS

One hundred and fifty-eight patients were included: 64 received dalbavancin and 94 received conventional therapy. The total ID-related cost of care per patient was greater with dalbavancin (mean $4,561) vs conventional (mean $1,668), p < 0.01. In the subset of patients treated with daptomycin, the total ID-related cost (mean $5,218) was comparable to dalbavancin (mean $4,561).

CONCLUSIONS

Dalbavancin was more costly than conventional therapy for the outpatient treatment of ABSSSI. This greater overall cost was likely driven by the higher acquisition cost of dalbavancin. Dalbavancin may be comparable to the daily use of daptomycin for ABSSSI.

Current and future treatment options for community-associated MRSA infection

INTRODUCTION

Community-associated MRSA (CA-MRSA) represents a global epidemic which beautifully encapsulates the fascinating ability of bacterial organisms to adapt quickly on an evolutionary basis to the extreme selective pressure of antibiotic exposure. In stark contrast to Healthcare-associated MRSA (HA-MRSA), it has become apparent that CA-MRSA is less straight forward of a challenge in terms of controlling its transmission, and has forced clinicians to adjust empiric management of clinical syndromes such as skin and soft tissue infection (SSTI) as well as pneumonia.

AREAS COVERED

This review details the history and epidemiology of CA-MRSA, while covering both current and future treatment options that are and may be available to clinicians. The authors reviewed both historic and more recent literature on this ever-evolving topic.

EXPERT OPINION

While development of new anti-MRSA agents should be encouraged, the importance of antimicrobial stewardship in the battle to stay ahead of the curve with regards to the ongoing control of the MRSA epidemic should be emphasised.

Cellulitis and Soft Tissue Infections

Cellulitis and soft tissue infections are a diverse group of diseases that range from uncomplicated cellulitis to necrotizing fasciitis. Management of predisposing conditions is the primary means of prevention. Cellulitis is a clinical diagnosis and thus is made on the basis of history and physical examination. Imaging may be helpful for characterizing purulent soft tissue infections and associated osteomyelitis. Treatment varies according to the type of infection. The foundations of treatment are drainage of purulence and antibiotics, the latter targeted at the infection's most likely cause.

The role of methicillin-resistant Staphylococcus aureus in skin and soft tissue infections

PURPOSE OF REVIEW

Methicillin-resistant Staphylococcus aureus (MRSA) has become a major public health issue worldwide over the last years. MRSA is frequently implicated in the development of skin and soft tissue infections, leading to significant increases in morbidity, mortality and overall healthcare costs.

RECENT FINDINGS

In order to face the threat of MRSA, major changes in clinical management of skin and soft tissue infections are required. The identification of populations at risk for the acquisition of infections due to MRSA, together with the improvement of the diagnostic techniques, is paramount. Moreover, a number of new antimicrobials with activity against MRSA have been recently developed and approved for the treatment of skin and soft tissue infections, however, the use of the new drugs in the wide clinical practice remains limited.

SUMMARY

We reviewed the current epidemiology of MRSA in skin and soft tissue infections, with particular focus on implications for clinical management. The potential role of new antibiotic options against MRSA infections is also discussed.

Are there any reasons to change our behavior in necrotizing fasciitis with the advent of new antibiotics?

PURPOSE OF REVIEW

The treatment of necrotizing fasciitis requires a multifaceted approach, consisting of surgical source control with immediate surgical debridement along with life support, clinical monitoring, and antimicrobial therapy. Many drugs are now available for the treatment of this life-threatening infectious disease, and the purpose of this review is to provide the reader with an updated overview of the newest therapeutic options.

RECENT FINDINGS

Because most necrotizing soft tissue infections are polymicrobial, broad-spectrum coverage is advisable. Acceptable monotherapy regimens include piperacillin-tazobactam or a carbapenem. However, drugs such as ceftolozane-tazobactam, ceftazidime-avibactam in association with an antianaerobic agent (metronidazole or clindamycin) are currently available as valuable alternatives. The new cephalosporins active against methicillin-resistant Staphylococcus aureus (MRSA), ceftaroline, and ceftobiprole share similar antibacterial activity against Gram-positive cocci, and they might be considered as an alternative to nonbetalactam anti-MRSA agents for necrotizing fasciitis management. Two new long-acting lypoglycopeptides - oritavancin and dalbavancin - share the indications for acute bacterial skin and skin structure infections and had similar activity against Gram-positive cocci including MRSA and streptococci.

SUMMARY

Carbapenem-sparing agents are particularly suitable for antimicrobial stewardship strategy. The new long-acting lypoglycopeptides are very effective in treating necrotizing fasciitis and are uttermost attractive for patients requiring short hospital stays and early discharge.

Dalbavancin treatment in a deep sternal wound MRSA infection after coronary artery bypass surgery: a case report

BACKGROUND

A deep sternal wound infection (DSWI) can become a severe complication after cardiac surgery, with in-hospital mortality rates reaching up to 35%. Staphylococci, particularly methicillin resistant Staphylococcus aureus (MRSA), play important roles in its etiology.

CASE PRESENTATION

This case report presents a patient who underwent coronary artery bypass surgery, and suffered postoperatively from a DSWI caused by MRSA. The pathogen was susceptible to vancomycin and rifampicin in vitro; however, this therapy was clinically ineffective. Both clinical improvement and MRSA eradication were achieved after surgical debridement of the wound and the intravenous administration of dalbavancin.

CONCLUSIONS

We decided to administer dalbavancin because of its convenient pharmacological profile. The patient's tolerance of the antimicrobial was good, the biochemical markers of inflammation returned to the normal ranges, and the microbiological results one week after the dalbavancin administration were negative. A good clinical outcome was achieved with both the surgery and antimicrobial administration. In this case, dalbavancin was more effective in the treatment of the sternal and surrounding tissue infections caused by MRSA, when compared to vancomycin.

What is new in the management of skin and soft tissue infections in 2016?

PURPOSE OF REVIEW

Skin and soft tissue infections (SSTIs) are the most frequent infectious cause of referrals to emergency departments and hospital admissions in developed world, contributing to significant morbidity and healthcare expenditures. We sought to review recent literature covering epidemiology and management of SSTIs.

RECENT FINDINGS

Incidence trends of SSTIs were increasing worldwide with Staphylococcus aureus and streptococci predominating and methicillin-resistant S. aureus (MRSA) posing additional challenges, because of high rates of treatment failure and relapse. Development of new antimicrobials was associated with an appraisal of regulatory definitions and endpoints. Prediction of clinical response can be very tricky, because of variable risk factors for recurrence or treatment failure, depending mostly on the host. Precise indications for new antimicrobials should be established; their integration into clinical practice algorithms may serve reduction of unnecessary admissions, overtreatment and total costs.

SUMMARY

New antimicrobials with activity against MRSA have been recently launched. Long-acting agents, mainly oritavancin and dalbavancin, provide the opportunity of single-dose treatment and early discharge. Further outpatient treatment options include new per os antibiotics such as oxazolidinones. Validated assessment tools are urgently needed to support decision-making toward rational resource utilization and delivery of optimal treatment.

In vitro analysis of the minimal inhibitory concentration values of different generations of anti-methicillin-resistant Staphylococcus aureus antibiotics

Methicillin-resistant Staphylococcus aureus (MRSA) resistance to antimicrobials may result in the increased risk of treatment failure. The objective of the study was to analyse in vitro MRSA susceptibility to vancomycin, linezolid, daptomycin, tigecycline, ceftaroline, dalbavancin, clindamycin, ciprofloxacin and trimethoprim/sulfamethoxazole. All MRSA strains isolated from hospitalised patients were analysed according to the current microbiological recommendations. Finally, a total of 124 MRSA strains were analysed; all were susceptible to tested antibiotics. Dalbavancin had the lowest minimum inhibitory concentration (MIC), and vancomycin the highest MIC value. There were 28/124 strains of MRSA susceptible for clindamycin, 36/124 for ciprofloxacin and 121/124 for trimethoprim/sulfamethoxazole. Dalbavancin was the most effective antimicrobial in our study.

New Antimicrobial Agents for the Treatment of Staphylococcal Infections in Children

Several new antimicrobial agents-daptomycin, ceftaroline, telavancin, dalbavancin, and-tedizolid have been approved for the treatment of staphylococcal infections, including methicillin-resistant Staphylococcus aureus (MRSA), in adults. Ceftaroline and daptomycin have been approved by the US Food and Drug Administration for use in children. Ceftaroline, a beta-lactam antibiotic with activity against MRSA, has been approved for treatment of community-acquired bacterial pneumonia and complicated skin and skin structure infections. Daptomycin has been approved for treatment of complicated skin and skin structure infections. In this article, we review the pharmacokinetics and pharmacodynamics of these antibiotics and available data on use in children.

Dalbavancin in the treatment of different gram-positive infections: a real-life experience

Dalbavancin is a lipoglycopeptide with a very prolonged half-life enabling treatment with a single intravenous administration that has been approved to treat complicated skin and soft-tissue infections. Information on the efficacy and safety of dalbavancin in other situations is very scarce. This retrospective study included adult patients who received at least one dose of dalbavancin between 2016 and 2017 in 29 institutions in Spain. The primary objective was to report the use of dalbavancin in clinical practice, including its efficacy and tolerability. The potential impact of dalbavancin on reducing the length of hospital stay and hospital costs was also evaluated. A total of 69 patients received dalbavancin during the study period (58.0% male; median age 63.5 years). Dalbavancin was used to treat prosthetic joint infection (29.0%), acute bacterial skin and skin-structure infection (21.7%), osteomyelitis (17.4%) and catheter-related bacteraemia (11.6%). These infections were mainly caused by Staphylococcus aureus (27 isolates), coagulase-negative staphylococci (24 isolates) and Enterococcus spp. (11 isolates). All but two patients received previous antibiotics for a median of 18 days. Dalbavancin was administered for a median of 21 days (range 7-168 days), and concomitant antimicrobial therapy was prescribed to 25 patients (36.2%). The overall clinical success rate of dalbavancin was 84.1%. Adverse events, mainly mild in intensity, were reported in nine patients. Overall, dalbavancin was estimated to reduce hospitalisation by 1160 days, with an estimated overall cost reduction of €211 481 (€3064 per patient). Dalbavancin appears to be an effective therapy for many serious Gram-positive infections.

Newer glycopeptide antibiotics for treatment of complicated skin and soft tissue infections: systematic review, network meta-analysis and cost analysis

OBJECTIVES

Skin and soft tissue infections (SSTIs) carry significant economic burden, as well as morbidity and mortality, especially when caused by methicillin-resistant Staphylococcus aureus (MRSA). Several new MRSA-active antibiotics have been developed, including semisynthetic glycopeptides (telavancin, dalbavancin and oritavancin). Of these, dalbavancin and oritavancin offer extended dosing intervals.

METHODS

We performed a systematic review, network meta-analysis and cost analysis to compare the newer glycopeptides to standard care and to each other for the treatment of complicated SSTIs (cSSTI). A search for randomized controlled trials (RCTs) was conducted in Medline, Embase and the Cochrane Central Register of Controlled Trials. We also developed a model to evaluate the costs associated with dalbavancin and oritavancin from the third-party payer perspective.

RESULTS

Seven RCTs met the inclusion criteria. Network meta-analyses suggested that the clinical response to telavancin, dalbavancin and oritavancin was similar to standard care (odds ratio (OR) 1.09, 95% confidence interval (CI) 0.90-1.33; OR 0.78, 95% CI 0.52-1.18; and OR 1.06, 95% CI 0.85-1.33, respectively). Head-to-head comparisons showed no difference in clinical response between oritavancin and dalbavancin (OR 1.36; 95% CI 0.85-2.18), oritavancin and telavancin (OR 0.98; 95% CI 0.72-1.31) or dalbavancin and telavancin (OR 0.72; 95% CI 0.45-1.13). Telavancin had a higher incidence of overall adverse events compared to standard care (OR 1.33; 95% CI 1.10-1.61). Compared to telavancin, there were fewer overall adverse events with dalbavancin (OR 0.58; 95% CI 0.45-0.76) and oritavancin (OR 0.71; 95% CI 0.55-0.92). Studies were of high quality overall. Our cost analyses demonstrated that dalbavancin and oritavancin were less costly compared to standard care under baseline assumptions and many scenarios evaluated. The use of dalbavancin could save third-party payers $1442 to $4803 per cSSTI, while the use of oritavancin could save $3571 to $6932 per cSSTI.

CONCLUSIONS

Dalbavancin and oritavancin demonstrate efficacy and safety comparable to standard care in well-designed RCTs and result in cost savings when standard care is treatment that covers MRSA.

Management of acute bacterial skin and skin structure infections with a focus on patients at high risk of treatment failure

Over the last 25 years, the terminology of skin and soft tissue infections, as well as their classification for optimal management of patients, has changed. The so-called and recently introduced term 'acute bacterial skin and skin structure infections' (ABSSSIs), a cluster of fairly common types of infection, including abscesses, cellulitis, and wound infections, require an immediate effective antibacterial treatment as part of a timely and cautious management. The extreme level of resistance globally to many antibiotic drugs in the prevalent causative pathogens, the presence of risk factors of treatment failure, and the high epidemic of comorbidities (e.g. diabetes and obesity) make the appropriate selection of the antibiotic for physicians highly challenging. The selection of antibiotics is primarily empirical for ABSSSI patients which subsequently can be adjusted based on culture results, although rarely available in outpatient management. There is substantial evidence suggesting that inappropriate antibiotic treatment is given to approximately 20-25% of patients, potentially prolonging their hospital stay and increasing the risk of morbidity and mortality. The current review paper discusses the concerns related to the management of ABSSSI and the patient types who are most vulnerable to poor outcomes. It also highlights the key management time-points that treating physicians and surgeons must be aware of in order to achieve clinical success and to discharge patients from the hospital as early as possible.

Emergence of dalbavancin non-susceptible, vancomycin-intermediate Staphylococcus aureus (VISA) after treatment of MRSA central line-associated bloodstream infection with a dalbavancin- and vancomycin-containing regimen

OBJECTIVES

Dalbavancin is a long-acting lipoglycopeptide with activity against gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA). The potential for lipoglycopeptides, with half-lives greater than 1 week, to select for resistance is unknown. Here we explore a case of MRSA central line-associated bloodstream infection in which dalbavancin and vancomycin non-susceptibility emerged in a urine isolate collected after the patient was treated with vancomycin and dalbavancin sequentially.

METHODS

Isolates from blood and urine underwent susceptibility testing, and whole genome sequencing (WGS). The blood isolate was subjected to successive passage in vitro in the presence of escalating dalbavancin concentrations and the emergent isolate was subjected to repeat susceptibility testing and WGS.

RESULTS

The blood isolate was fully susceptible to vancomycin; however, MICs of the urine isolate to dalbavancin, vancomycin, telavancin, and daptomycin were at least fourfold higher than the blood-derived strain. Both strains were indistinguishable by spa and variable number tandem repeat (VNTR) typing, and WGS revealed only seven variants, indicating clonality. Four variants affected genes, including a 3bp in-frame deletion in yvqF, a gene which has been implicated in glycopeptide resistance. Vancomycin and dalbavancin non-susceptibility emerged in the blood isolate after successive passage in vitro in the presence of dalbavancin, and WGS identified a single non-synonymous variant in yvqF.

CONCLUSIONS

This is the first case in which VISA has emerged in the context of a dalbavancin-containing regimen. The selection for cross-resistance to vancomycin in vitro by dalbavancin exposure alone is troubling. Clinicians should be aware of the possibility for emergence of dalbavancin non-susceptibility and glycopeptide cross-resistance arising following therapy.

Dalbavancin for outpatient parenteral antimicrobial therapy of skin and soft tissue infections in a returning traveller : Proposal for novel treatment indications

Skin and soft tissue infections (SSTIs) are among the most common health problems in travellers returning from tropical and subtropical countries. Importantly, the prevalence of Staphylococcus aureus, the most common pathogen for purulent SSTIs, with specific drug resistance, such as methicillin resistant Staphylococcus aureus (MRSA) and those expressing virulence genes, such as Panton-Valentine-leukocidin is higher in tropical regions than in most high resource settings. This poses challenges for the empirical antimicrobial treatment of SSTIs in returning travellers. This short report describes a patient with a recent travel history to Hong Kong, Singapore and the Philippines who presented with multiple mosquito bites on both upper extremities and secondary bacterial superinfection. He had previously been prescribed oral beta-lactam antimicrobial therapy but lacked adherence to this treatment. Based on the risk for MRSA infection and problems with treatment adherence to oral therapy an outpatient parenteral antimicrobial therapy with dalbavancin was administered on days 0 and 7. Microbiological culture confirmed presence of MRSA and clinical follow-up demonstrated complete remission of the SSTI within 2 weeks. Dalbavancin is a promising treatment option for empirical parenteral treatment of SSTIs in returning travellers, a population at high risk for beta-lactam resistant S. aureus skin infections.

Future trends in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infection: An in-depth review of newer antibiotics active against an enduring pathogen

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major public health problem. Vancomycin and teicoplanin have been in clinical use for several decades but their drawbacks are well described. In the last 10 years, several antibiotics have been made available for clinical use. Daptomycin and linezolid have been extensively used during this period. Other agents such as ceftaroline, ceftobiprole, dalbavancin, oritavancin, tedizolid and telavancin have been approved by regulatory agencies since 2009. Many others, such as the newer tetracyclines, fluoroquinolones, oxazolidinones and pleuromutilins, are in various stages of development. In addition, an ongoing multicentre trial is investigating the role of combination of vancomycin or daptomycin with β-lactam antibiotics. This review discusses the role of the newer antibiotics, reflecting the views of the 6th MRSA Consensus Conference meeting of the International Society of Chemotherapy MRSA Working Group that took place in 2016.

Dalbavancin Pharmacokinetics and Safety in Children 3 Months to 11 Years of Age

BACKGROUND

Dalbavancin is a novel lipoglycopeptide antibiotic that has potent in vitro activity against Gram-positive microorganisms.

METHODS

We performed a phase 1, open-label, multicenter study to investigate the pharmacokinetics (PK) and safety of a single dose of intravenous dalbavancin in hospitalized pediatric subjects 3 months to 11 years of age. We combined these data with previously collected adolescent PK data and performed a population PK analysis.

RESULTS

Model development was performed using 311 dalbavancin plasma concentrations from 43 subjects. The median age was 5.9 years (range: 0.3-16.9). A 3-compartment, linear PK model was developed. Based on simulations, the following age-dependent dosing regimen was found to achieve similar dalbavancin exposure to that in adults administered a 2-dose regimen: children 6 to <18 years of age, 12 mg/kg (1000 mg maximum) on day 1 and 6 mg/kg (500 mg maximum) on day 8 and children 3 months to <6 years of age, 15 mg/kg (1000 mg maximum) on day 1 and 7.5 mg/kg (500 mg maximum) on day 8. Similarly, the following age-dependent regimen was found to match adult exposure after a single-dose (1500 mg): 6 to <18 years of age, 18 mg/kg (1500 mg maximum) on day 1 and 3 months to <6 years of age, 22.5 mg/kg (1500 mg maximum) on day 1. Nineteen subjects experienced 36 treatment-emergent adverse events. Five of 36 adverse events were assessed as possibly or probably related to treatment.

CONCLUSIONS

Dalbavancin pediatric dosing that matched adult exposure was identified. Overall, dalbavancin was well tolerated in our study population.

Early recognition of methicillin-resistant Staphylococcus aureus surgical site infections using risk and protective factors identified by a group of Italian surgeons through Delphi method

BACKGROUND

Surgical site infections (SSIs) constitute a major clinical problem in terms of morbidity, mortality, duration of hospital stay, and overall costs. The bacterial pathogens implicated most frequently are Streptococcus pyogenes (S. pyogenes) and Staphylococcus aureus (S. aureus). The incidence of methicillin-resistant S. aureus (MRSA) SSIs is increasing significantly. Since these infections have a significant impact on hospital budgets and patients' health, their diagnosis must be anticipated and therapy improved. The first step should be to evaluate risk factors for MRSA SSIs.

METHODS

Through a literature review, we identified possible major and minor risk factors for, and protective factors against MRSA SSIs. We then submitted statements on these factors to 228 Italian surgeons to determine, using the Delphi method, the degree of consensus regarding their importance. The consensus was rated as positive if >80% of the voters agreed with a statement and as negative if >80% of the voters disagreed. In other cases, no consensus was reached.

RESULTS

There was positive consensus that sepsis, >2 weeks of hospitalization, age >75 years, colonization by MRSA, and diabetes were major risk factors for MRSA SSIs. Other possible major risk factors, on which a consensus was not reached, e.g., prior antibiotic use, were considered minor risk factors. Other minor risk factors were identified. An adequate antibiotic prophylaxis, laparoscopic technique, and infection committee surveillance were considered protective factors against MRSA SSIs. All these factors might be used to build predictive criteria for identifying SSI due to MRSA.

CONCLUSIONS

In order to help to recognize and thus promptly initiate an adequate antibiotic therapy for MRSA SSIs, we designed a gradation of risk and protective factors. Validation, ideally prospective, of this score is now required. In the case of a SSI, if the risk that the infection is caused by MRSA is high, empiric antibiotic therapy should be started after debriding the wound and collecting material for culture.

Single-Dose Dalbavancin: A Review in Acute Bacterial Skin and Skin Structure Infections

Intravenous dalbavancin (Dalvance^®, Xydalba^®), first approved as a two-dose regimen for the treatment of acute bacterial skin and skin structure infections (ABSSSI), has now been additionally approved as a single-dose regimen. This narrative review discusses the pharmacological properties of intravenous dalbavancin and its clinical efficacy and tolerability as a single-dose regimen in the treatment of adult patients with ABSSSI. Single-dose dalbavancin is an effective and generally well tolerated treatment option for adults with ABSSSI, with noninferior efficacy to the two-dose dalbavancin regimen with regard to early clinical response (at 48-72 h) and low rates of adverse events. Clinical success rates at days 14 and 28 also did not significantly differ between the single- and two-dose dalbavancin regimens; neither did clinical success rates at day 14 when analysed by baseline pathogen. It has a broad spectrum of activity against common ABSSSI-related pathogens, and a favourable pharmacokinetic profile allowing for the convenience of single-dose administration. Thus, dalbavancin presents a promising alternative to conventional antibacterials for the treatment of ABSSSI in adult patients.

Diagnosis and management of skin and soft-tissue infections (SSTI). A literature review and consensus statement: an update

Skin and soft-tissue infections (SSTIs) are among the most common bacterial infections, posing considerable diagnostic and therapeutic challenges. Fourteen members of the Italian Society of Infectious Diseases, after a careful review of the most recent literature using Medline database and their own clinical experience, updated a previous paper published in 2011 by preparing a draught manuscript of the statements. The manuscript was successively reviewed by all members and ultimately re-formulated the present manuscript during a full day consensus meeting. The microbiological and clinical aspects together with diagnostic features were considered for necrotizing and not necrotizing SSTIs in the light of the most recent guidelines and evidences published in the last five years. The antimicrobial therapy was considered as well - both empirical and targeted to methicillin-resistant Staphylococcus aureus and/or other pathogens, also taking into account the epidemiological and bacterial resistance data and the availability of new antibacterial agents.

Predictive score of haematological toxicity in patients treated with linezolid

OBJECTIVE

The aims of our study were to determine the factors associated with developing haematological toxicity (HT) in patients taking linezolid (LZD), to develop a predictive model of HT in these patients, and to evaluate factors associated with 30-day mortality.

METHODS

This was an observational retrospective cohort study of patients treated for at least 5 days with LDZ in 2015. Demographic, clinical and analytical data were collected. Development of HT was defined as a 25% platelet count decrease between the basal count and the 1-week lab test.

RESULTS

Five hundred forty-nine patients were finally included, mean age was 73.3 (SD 15.4) years, and 303 (55.2%) were men. One hundred seventy-five (30.1%) patients achieved HT criteria during treatment with LZD and 41 (7.5%) died. The final model included the presence of cerebrovascular disease (2 points), moderate or severe liver disease (2 points), renal failure (2 points) and basal platelet count less than 90,000/mm3 (8 points). This new model showed an AUC of 0.711 (IC 95% 0.664-0.757; p < 0.001) to predict the development of HT. The probability of HT based on this classification was 6.2, 29.9 and 76.5% for low (0-4 points), intermediate (5-10 points) and high risk (>10 points), respectively. The independent variables associated with 30-day mortality were metastatic solid tumor, lymphoma, age >75 years and HT.

CONCLUSION

This score could help in the identification of patients with high risk for HT and assess the use of an antibiotic other than LZD, an important issue considering its relation with 30-day mortality observed in our study.

Dosing strategies to optimize currently available anti-MRSA treatment options (Part 1: IV options)

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a predominant pathogen resulting in significant morbidity and mortality. Optimal dosing of anti-MRSA agents is needed to help prevent the development of antimicrobial resistance and to increase the likelihood of a favorable clinical outcome. Areas covered: This review summarizes the available data for antimicrobials routinely used for MRSA infections that are not administered orally or topically. We make recommendations and highlight the current gaps in the literature. A PubMed (1966 - Present) search was performed to identify relevant literature for this review. Expert commentary: Improvements in MIC determination and therapeutic drug monitoring are needed to fully implement individualized dosing that optimizes antimicrobial pharmacodynamics.Additional data will become available for these agents in regards to effectiveness for severe MRSA infections and pharmacokinetic data for special patient populations.

Pharmacokinetic drug evaluation of tedizolid for the treatment of skin infections

INTRODUCTION

Tedizolid is indicated for the treatment of acute bacterial skin and skin structure infections (ABSSSI). Although tedizolid shares many similar properties with linezolid, another oxazolidinone used to treat ABSSSI, the two antibiotics have several key differences. Areas covered: This review provides a detailed summary of the overall pharmacodynamics, pharmacokinetics, clinical efficacy, and safety of tedizolid for the treatment of ABSSSI. Expert opinion: Compared to other antibiotics used for ABSSSI, tedizolid has several advantages. Tedizolid has a long half-life, allowing for once daily dosing. Tedizolid also has broad spectrum of activity against Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus, Coagulase-negative Staphylococci, and Enterococci - including isolates demonstrating resistance to linezolid. It is available in both oral and intravenous formulations, and, has outstanding oral bioavailability, allowing for oral-step down therapy. There is also some evidence that, tedizolid has fewer significant interactions with serotonin reuptake inhibitors or monoamine oxidase inhibitors than linezolid. Finally, thrombocytopenia may occur less often with tedizolid than linezolid. However, these benefits must be weighed against the financial cost of tedizolid and the availability of alternative antibiotic choices.

Treatment of Staphylococcus aureus Infections

Staphylococcus aureus, although generally identified as a commensal, is also a common cause of human bacterial infections, including of the skin and other soft tissues, bones, bloodstream, and respiratory tract. The history of S. aureus treatment is marked by the development of resistance to each new class of antistaphylococcal antimicrobial drugs, including the penicillins, sulfonamides, tetracyclines, glycopeptides, and others, complicating therapy. S. aureus isolates identified in the 1960s were sometimes resistant to methicillin, a ß-lactam antimicrobial active initially against a majority S. aureus strains. These MRSA isolates, resistant to nearly all ß-lactam antimicrobials, were first largely confined to the health care environment and the patients who attended it. However, in the mid-1990s, new strains, known as community-associated (CA-) MRSA strains, emerged. CA-MRSA organisms, compared with health care-associated (HA-) MRSA strain types, are more often susceptible to multiple classes of non ß-lactam antimicrobials. While infections caused by methicillin-susceptible S. aureus (MSSA) strains are usually treated with drugs in the ß-lactam class, such as cephalosporins, oxacillin or nafcillin, MRSA infections are treated with drugs in other antimicrobial classes. The glycopeptide drug vancomycin, and in some countries teicoplanin, is the most common drug used to treat severe MRSA infections. There are now other classes of antimicrobials available to treat staphylococcal infections, including several that have been approved after 2009. The antimicrobial management of invasive and noninvasive S. aureus infections in the ambulatory and in-patient settings is the topic of this review. Also discussed are common adverse effects of antistaphylococcal antimicrobial agents, advantages of one agent over another for specific clinical syndromes, and the use of adjunctive therapies such as surgery and intravenous immunoglobulin. We have detailed considerations in the therapy of noninvasive and invasive S. aureus infections. This is followed by sections on specific clinical infectious syndromes including skin and soft tissue infections, bacteremia, endocarditis and intravascular infections, pneumonia, osteomyelitis and vertebral discitis, epidural abscess, septic arthritis, pyomyositis, mastitis, necrotizing fasciitis, orbital infections, endophthalmitis, parotitis, staphylococcal toxinoses, urogenital infections, and central nervous system infections.

Methicillin-resistant Staphylococcus aureus infections: A review of the currently available treatment options

This review is the result of discussions that took place at the 5th MRSA Working Group Consensus Meeting and explores the possible treatment options available for different types of infections due to methicillin-resistant Staphylococcus aureus (MRSA), focusing on those antibiotics that could represent a valid alternative to vancomycin. In fact, whilst vancomycin remains a viable option, its therapy is moving towards individualised dosing. Other drugs, such as the new lipoglycopeptides (oritavancin, dalbavancin and telavancin) and fifth-generation cephalosporins (ceftaroline and ceftobiprole), are showing good in vitro potency and in vivo efficacy, especially for patients infected with micro-organisms with higher vancomycin minimum inhibitory concentrations (MICs). Tedizolid is an attractive agent for use both in hospital and community settings, but the post-marketing data will better clarify its potential. Daptomycin and linezolid have shown non-inferiority to vancomycin in the treatment of MRSA bacteraemia and non-inferiority/superiority to vancomycin in the treatment of hospital-acquired pneumonia. Thus, several options are available, but more data from clinical practice, especially for invasive infections, are needed to assign specific roles to each antibiotic and to definitely include them in the new antibacterial armamentarium.