Multicenter, randomized study of the efficacy and safety of intravenous iclaprim in complicated skin and skin structure infections

Treatment of MRSA Infection: Where are We?

Staphylococcus aureus is a leading cause of septicemia, endocarditis, pneumonia, skin and soft tissue infections, bone and joint infections, and hospital-acquired infections. In particular, methicillin-resistant Staphylococcus aureus (MRSA) is associated with high morbidity and mortality, and continues to be a major public health problem. The emergence of multidrug-resistant MRSA strains along with the wide consumption of antibiotics has made anti-MRSA treatment a huge challenge. Novel treatment strategies (e.g., novel antimicrobials and new administrations) against MRSA are urgently needed. In the past decade, pharmaceutical companies have invested more in the research and development (R&D) of new antimicrobials and strategies, spurred by favorable policies. All research articles were collected from authentic online databases, including Google Scholar, PubMed, Scopus, and Web of Science, by using different combinations of keywords, including 'anti-MRSA', 'antibiotic', 'antimicrobial', 'clinical trial', 'clinical phase', clinical studies', and 'pipeline'. The information extracted from articles was compared to information provided on the drug manufacturer's website and Clinical Trials.gov (https://clinicaltrials.gov/) to confirm the latest development phase of anti-MRSA agents. The present review focuses on the current development status of new anti-MRSA strategies concerning chemistry, pharmacological target(s), indications, route of administration, efficacy and safety, pharmacokinetics, and pharmacodynamics, and aims to discuss the challenges and opportunities in developing drugs for anti-MRSA infections.

Efficacy and safety of optional parenteral antimicrobial therapy for complicated skin and soft tissue infections: A systematic review and Bayesian network meta-analysis

BACKGROUND

Skin and soft tissue infections (SSTIs) carry significant economic burden, as well as morbidity and mortality, especially when caused by methicillin-resistant Staphylococcus aureus. This study aims to investigate the efficacy and safety of optional antimicrobial therapy for the treatment of complicated SSTIs (cSSTIs).

METHODS

We searched PubMed, Medline (Via Ovid SP), Embase (Via Ovid SP), and the Cochrane Central Register of Controlled Trials from their inception to March 22, 2021 for randomized controlled trials (RCTs) that studied the use of optional antimicrobial therapy for cSSTIs. Citations' screening, study selection, data extraction, and risk of bias assessment were independently performed by 2 authors. The primary outcomes were clinical and microbiological treatment success, and adverse events (AEs) were also assessed.

RESULTS

A total of 48 trials covering 24,381 patients assessing 20 types of antimicrobial treatment modalities were included. Overall, omadacycline was associated with the highest beneficial effect on clinical and microbiological treatment success and with the largest rank probability based on surface under the cumulative ranking curve values, avarofloxacin was closely followed. Both had, however, omadacycline was related to moderately safety profiles. Lefamulin ranked as the best option was associated with the lowest risk of severe AEs. Subgroup analysis showed similar results. The quality of primary outcomes was moderate to low.

CONCLUSIONS

The use of omadacycline was associated with higher rates of clinical and microbiological treatment success for the treatment of cSSTIs, with a relative low risk of AEs. Due to the limitations of the included RCTs, high-quality and well-designed RCTs are needed to further confirm the results.

Efficacy and Safety of Iclaprim for the Treatment of Skin Structures and Soft Tissue Infections: A Methodological Framework

Background: Skin and soft tissue infections (SSTIs) are among the most common infections worldwide. They manifest in a variety of forms, such as erysipelas, cellulitis, and necrotizing fasciitis. Antibiotics are the significant method for clinical treatment of SSTIs. This study reported a methodology framework to determine the efficacy and safety of iclaprim in treatment of SSTIs.

Methods: We will search the PubMed, EMbase, CNKI, WanFang Data, VIP, and ClinicalTrials.gov from their inception to June 2022 for randomized controlled trials and cohort studies on iclaprim with SSTIs. Two authors will independently screen the eligible studies, assess the quality of the included papers, and extract the required information. Randomized controlled trials will be assessed using the Cochrane risk-of-bias tool. The Newcastle–Ottawa Scale will be used to evaluate observational studies. The quality of the evidence will be evaluated using the Grading of Recommendations Assessment Development and Evaluation system. RevMan 5.3 will be used for the data synthesis and quantitative analysis.

Results and Discussions: This study will provide the clinicians with more high-quality evidence to choose iclaprim for patients with SSTIs.

Ethics and Dissemination: This systematic review and meta-analysis will be based on published data, so ethical approval is not necessary. The results of this meta-analysis will be published in a peer-reviewed journal.

Emerging Treatment Options for Infections by Multidrug-Resistant Gram-Positive Microorganisms

Antimicrobial agents are currently the mainstay of treatment for bacterial infections worldwide. However, due to the increased use of antimicrobials in both human and animal medicine, pathogens have now evolved to possess high levels of multi-drug resistance, leading to the persistence and spread of difficult-to-treat infections. Several current antibacterial agents active against Gram-positive bacteria will be rendered useless in the face of increasing resistance rates. There are several emerging antibiotics under development, some of which have been shown to be more effective with an improved safety profile than current treatment regimens against Gram-positive bacteria. We will extensively discuss these antibiotics under clinical development (phase I-III clinical trials) to combat Gram-positive bacteria, such as Staphylococcus aureus, Enterococcus faecium and Streptococcus pneumoniae. We will delve into the mechanism of actions, microbiological spectrum, and, where available, the pharmacokinetics, safety profile, and efficacy of these drugs, aiming to provide a comprehensive review to the involved stakeholders.

Iclaprim: a differentiated option for the treatment of skin and skin structure infections

INTRODUCTION

Iclaprim is a selective bacterial dihydrofolate reductase (DHFR) inhibitor. Although there are alternative options for the treatment of acute bacterial skin and skin structure infections (ABSSSI), iclaprim is differentiated from other available antibiotics. Areas covered: Iclaprim is under clinical development for ABSSSI. This review summarizes the mechanism of action, pharmacokinetics, microbiology, clinical development program, and the differentiation of iclaprim from other antibiotics. Expert commentary: Iclaprim has a different mechanism of action (DHFR inhibitor) compared to most other antibiotics, is active and rapidly bactericidal against Gram-positive pathogens including antibiotic-resistant pathogens, and suppresses bacterial exotoxins (alpha hemolysin, Panton Valentine leukocidin, and toxic shock syndrome toxin-1). Compared to trimethoprim, iclaprim has lower MIC_90s, can be given without a sulfonamide, overcomes select trimethoprim resistance, and does not cause hyperkalemia. Iclaprim is administered as a fixed dose, does not require dose adjustment in renally-impaired or obese patients, and was not associated with nephrotoxicity in the Phase 3 pivotal REVIVE studies. Iclaprim represents a novel, alternative option for the treatment of severe skin and skin structure infections due to Gram-positive bacteria, particularly in patients at risk of acute kidney injury.

Iclaprim, a dihydrofolate reductase inhibitor antibiotic in Phase III of clinical development: a review of its pharmacology, microbiology and clinical efficacy and safety

Iclaprim is under clinical development for treating acute bacterial skin and skin structure infections (ABSSSI) and nosocomial pneumonia most often due to Gram-positive bacteria, including infections due to drug-resistant bacteria. In two recent Phase III studies of patients with acute bacterial skin and skin structure infections, intravenous iclaprim 80 mg every 12 h was noninferior to dose-adjusted vancomycin. Additional studies are planned for patients with nosocomial pneumonia. Iclaprim represents an alternative for the treatment of severe skin and pulmonary infections due to Gram-positive bacteria.

Antibiotic resistance in Staphylococcus aureus. Current status and future prospects

The major targets for antibiotics in staphylococci are (i) the cell envelope, (ii) the ribosome and (iii) nucleic acids. Several novel targets emerged from recent targeted drug discovery programmes including the ClpP protease and FtsZ from the cell division machinery. Resistance can either develop by horizontal transfer of resistance determinants encoded by mobile genetic elements viz plasmids, transposons and the staphylococcal cassette chromosome or by mutations in chromosomal genes. Horizontally acquired resistance can occur by one of the following mechanisms: (i) enzymatic drug modification and inactivation, (ii) enzymatic modification of the drug binding site, (iii) drug efflux, (iv) bypass mechanisms involving acquisition of a novel drug-resistant target, (v) displacement of the drug to protect the target. Acquisition of resistance by mutation can result from (i) alteration of the drug target that prevents the inhibitor from binding, (ii) derepression of chromosomally encoded multidrug resistance efflux pumps and (iii) multiple stepwise mutations that alter the structure and composition of the cell wall and/or membrane to reduce drug access to its target. This review focuses on development of resistance to currently used antibiotics and examines future prospects for new antibiotics and informed use of drug combinations.

An Updated Review of Iclaprim: A Potent and Rapidly Bactericidal Antibiotic for the Treatment of Skin and Skin Structure Infections and Nosocomial Pneumonia Caused by Gram-Positive Including Multidrug-Resistant Bacteria

New antibiotics are needed because of the increased morbidity and mortality associated with multidrug-resistant bacteria. Iclaprim, a bacterial dihydrofolate reductase inhibitor, not currently approved, is being studied for the treatment of skin infections and nosocomial pneumonia caused by Gram-positve bacteria, including multidrug-resistant bacteria. Iclaprim showed noninferiority at -10% to linezolid in 1 of 2 phase 3 studies for the treatment of complicated skin and skin structure infections with a weight-based dose (0.8 mg/kg) but did not show noninferiority at -10% to linezolid in a second phase 3 study. More recently, iclaprim has shown noninferiority at -10% to vancomycin in 2 phase 3 studies for the treatment of acute bacterial skin and skin structure infections with an optimized fixed dose (80 mg). A phase 3 study for the treatment of hospital-acquired bacterial and ventilator-associated bacterial pneumonia is upcoming. If, as anticipated, iclaprim becomes available for the treatment of skin and skin structure infections, it will serve as an alternative to current antibiotics for treatment of severe infections. This article will provide an update to the chemistry, preclinical, pharmacology, microbiology, clinical and regulatory status of iclaprim.

A Phase II Randomized, Double-blind, Multicenter Study to Evaluate Efficacy and Safety of Intravenous Iclaprim Versus Vancomycin for the Treatment of Nosocomial Pneumonia Suspected or Confirmed to be Due to Gram-positive Pathogens

PURPOSE

The primary objective of this Phase II study was to compare the clinical cure rates of 2 iclaprim dosages versus vancomycin in the treatment of patients with nosocomial pneumonia suspected or confirmed to be caused by gram-positive pathogens.

METHODS

This study was a double-blind, randomized, multicenter trial. A total of 70 patients were randomized 1:1:1 to receive iclaprim 0.8 mg/kg IV q12h (iclaprim q12h; n = 23), iclaprim 1.2 mg/kg IV q8h (iclaprim q8h; n = 24), or vancomycin 1 g IV q12h (vancomycin; n = 23) for 7 to 14 days. The primary end point was clinical cure in the intention-to-treat population at test of cure (TOC; 7 [1] days' posttreatment) visit.

FINDINGS

The baseline and demographic characteristics of patients treated with either iclaprim or vancomycin were comparable. Cure rates in the intention-to-treat population were 73.9% (17 of 23), 62.5% (15 of 24), and 52.2% (12 of 23) at the TOC visit in the iclaprim q12h, iclaprim q8h, and vancomycin groups, respectively (iclaprim q12h vs vancomycin, P = 0.13; iclaprim q8h vs vancomycin, P = 0.47). The death rates within 28 days of the start of treatment were 8.7% (2 of 23), 12.5% (3 of 24), and 21.7% (5 of 23) for the iclaprim q12h, iclaprim q8h, and vancomycin groups (no statistically significant differences). The adverse event profile of both iclaprim dosing regimens was similar to that of vancomycin.

IMPLICATIONS

Iclaprim had clinical cure rates and a safety profile comparable with vancomycin among patients with nosocomial pneumonia. Iclaprim could be an important new therapeutic option for the treatment of nosocomial pneumonia, and a pivotal clinical trial is warranted to evaluate its safety and efficacy in this indication.

Comparative efficacy of antibiotics for the treatment of acute bacterial skin and skin structure infections (ABSSSI): a systematic review and network meta-analysis

OBJECTIVE

The objective was to conduct a systematic review and network meta-analysis (NMA) of existing treatments for ABSSSI focusing on the novel lipoglycopeptide oritavancin.

METHODS

EMBASE, MEDLINE, MEDLINE in Process, CENTRAL (Cochrane), and select conferences were searched for randomized controlled trials investigating antimicrobial agents for the treatment of ABSSSI. NMA was used to estimate the odds ratios of the Test-Of-Cure (TOC) and Early Clinical Response (ECR) outcomes for treatments relative to vancomycin in the ITT populations. Sub-group analyses in MRSA and MSSA populations were conducted for TOC; sensitivity analyses investigated the use of the clinically evaluable (CE) populations and the restriction to trials following the recent FDA guidelines for clinical trials.

RESULTS

The systematic review identified 52 trials. The most commonly investigated treatments were vancomycin and linezolid; most trials reported TOC, but not ECR. The posterior mean and 95% credible intervals for odds ratios of TOC for antimicrobial agents relative to vancomycin were: linezolid (1.55; 0.91-2.57), daptomycin (2.18; 0.90-5.42), and oritavancin 1200 mg (1.06; 0.80-1.43). The odds ratio of ECR for oritavancin 1200 mg was 1.02 (0.23-4.33). In the MRSA sub-group the odds ratios relative to vancomycin for TOC were: linezolid (1.55; 0.96-2.46), daptomycin (0.74; 0.13-3.66), and oritavancin 1200 mg (0.94; 0.44-2.02). In the MSSA sub-group they were linezolid (1.36; 0.15-13.34) and oritavancin 1200 mg (0.82; 0.08-7.83). These results were robust to the sensitivity analyses.

CONCLUSIONS

This NMA provides a unified framework for the comparison of all available antimicrobial agents used in the treatment of ABSSSI and is the first to assess the ECR end-point. The results suggest equivalence of clinical efficacy between vancomycin, daptomycin, linezolid, and novel antimicrobial agents including oritavancin for the treatment of ABSSSI at TOC. The wide uncertainty margins indicate the heterogeneity of the available evidence and the need for further research.

Staphylococcus aureus infections: epidemiology, pathophysiology, clinical manifestations, and management

Staphylococcus aureus is a major human pathogen that causes a wide range of clinical infections. It is a leading cause of bacteremia and infective endocarditis as well as osteoarticular, skin and soft tissue, pleuropulmonary, and device-related infections. This review comprehensively covers the epidemiology, pathophysiology, clinical manifestations, and management of each of these clinical entities. The past 2 decades have witnessed two clear shifts in the epidemiology of S. aureus infections: first, a growing number of health care-associated infections, particularly seen in infective endocarditis and prosthetic device infections, and second, an epidemic of community-associated skin and soft tissue infections driven by strains with certain virulence factors and resistance to β-lactam antibiotics. In reviewing the literature to support management strategies for these clinical manifestations, we also highlight the paucity of high-quality evidence for many key clinical questions.

Antibiotic therapy for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) in non surgical wounds

BACKGROUND

Non surgical wounds include chronic ulcers (pressure or decubitus ulcers, venous ulcers, diabetic ulcers, ischaemic ulcers), burns and traumatic wounds. The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonisation (i.e. presence of MRSA in the absence of clinical features of infection such as redness or pus discharge) or infection in chronic ulcers varies between 7% and 30%. MRSA colonisation or infection of non surgical wounds can result in MRSA bacteraemia (infection of the blood) which is associated with a 30-day mortality of about 28% to 38% and a one-year mortality of about 55%. People with non surgical wounds colonised or infected with MRSA may be reservoirs of MRSA, so it is important to treat them, however, we do not know the optimal antibiotic regimen to use in these cases.

OBJECTIVES

To compare the benefits (such as decreased mortality and improved quality of life) and harms (such as adverse events related to antibiotic use) of all antibiotic treatments in people with non surgical wounds with established colonisation or infection caused by MRSA.

SEARCH METHODS

We searched the following databases: The Cochrane Wounds Group Specialised Register (searched 13 March 2013); The Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2); Database of Abstracts of Reviews of Effects (2013, Issue 2); NHS Economic Evaluation Database (2013, Issue 2); Ovid MEDLINE (1946 to February Week 4 2013); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, March 12, 2013); Ovid EMBASE (1974 to 2013 Week 10); EBSCO CINAHL (1982 to 8 March 2013).

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) comparing antibiotic treatment with no antibiotic treatment or with another antibiotic regimen for the treatment of MRSA-infected non surgical wounds. We included all relevant RCTs in the analysis, irrespective of language, publication status, publication year, or sample size.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified the trials, and extracted data from the trial reports. We calculated the risk ratio (RR) with 95% confidence intervals (CI) for comparing the binary outcomes between the groups and planned to calculate the mean difference (MD) with 95% CI for comparing the continuous outcomes. We planned to perform the meta-analysis using both fixed-effect and random-effects models. We performed intention-to-treat analysis whenever possible.

MAIN RESULTS

We identified three trials that met the inclusion criteria for this review. In these, a total of 47 people with MRSA-positive diabetic foot infections were randomised to six different antibiotic regimens. While these trials included 925 people with multiple pathogens, they reported the information on outcomes for people with MRSA infections separately (MRSA prevalence: 5.1%). The only outcome reported for people with MRSA infection in these trials was the eradication of MRSA. The three trials did not report the review's primary outcomes (death and quality of life) and secondary outcomes (length of hospital stay, use of healthcare resources and time to complete wound healing). Two trials reported serious adverse events in people with infection due to any type of bacteria (i.e. not just MRSA infections), so the proportion of patients with serious adverse events was not available for MRSA-infected wounds. Overall, MRSA was eradicated in 31/47 (66%) of the people included in the three trials, but there were no significant differences in the proportion of people in whom MRSA was eradicated in any of the comparisons, as shown below.1. Daptomycin compared with vancomycin or semisynthetic penicillin: RR of MRSA eradication 1.13; 95% CI 0.56 to 2.25 (14 people).2. Ertapenem compared with piperacillin/tazobactam: RR of MRSA eradication 0.71; 95% CI 0.06 to 9.10 (10 people).3. Moxifloxacin compared with piperacillin/tazobactam followed by amoxycillin/clavulanate: RR of MRSA eradication 0.87; 95% CI 0.56 to 1.36 (23 people).

AUTHORS' CONCLUSIONS

We found no trials comparing the use of antibiotics with no antibiotic for treating MRSA-colonised non-surgical wounds and therefore can draw no conclusions for this population. In the trials that compared different antibiotics for treating MRSA-infected non surgical wounds, there was no evidence that any one antibiotic was better than the others. Further well-designed RCTs are necessary.

New therapy options for MRSA with respiratory infection/pneumonia

PURPOSE OF REVIEW

Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent causative agent of nosocomial pneumonia. Because of important clinical consequences of inappropriate treatment, a current review of the potential modifications undergone by S. aureus and adaptation to new treatment options is necessary.

RECENT FINDINGS

Vancomycin has been considered the treatment of choice for pneumonia due to MRSA. However, detection of a progressive increase in the minimum inhibitory concentration for this antibiotic, its limited access to the lung parenchyma, and its considerable adverse effects have called into question its position. Linezolid has been shown to have a better pharmacokinetic and safety profiles. The prior uncertainty regarding the clinical superiority of linezolid appears to have been resolved with the publication of a recent trial. Linezolid achieved a higher clinical and microbiological response rate (the latter was not statistically significant), together with a lower incidence of all types of renal adverse effects in patients with nosocomial pneumonia, compared with vancomycin. Tigecycline, teicoplanin and quinupristin/dalfopristin were inferior to the compared drug in their respective clinical trials. The clinical efficacy of telavancin was similar to that of vancomycin. The renal adverse effects of telavancin have to be clarified. Other drugs are efficacious against MRSA but their profile should be evaluated in nosocomial pneumonia.

SUMMARY

Current therapeutic alternatives for nosocomial pneumonia due to MRSA appear to be limited to vancomycin and linezolid. However, vancomycin pitfalls, together with the apparent clinical superiority of linezolid, appear to restrict its indication. Telavancin could be a good alternative in patients without basal renal failure.

Meta-analysis of randomized controlled trials of vancomycin for the treatment of patients with gram-positive infections: focus on the study design

OBJECTIVE

To study the effectiveness and safety of vancomycin compared with that of other antibiotics for the treatment of gram-positive infections.

METHODS

Major electronic databases were searched. Data from published randomized controlled trials (January 1, 1950, to September 15, 2011) were pooled using a meta-analytic method.

RESULTS

Fifty-three trials comparing vancomycin with linezolid, daptomycin, quinupristin-dalfopristin, tigecycline, ceftaroline, ceftobiprole, telavancin, teicoplanin, iclaprim, and dalbavancin were included in the meta-analysis. Individual antibiotics were as effective as vancomycin, except for linezolid, which was more effective than vancomycin for the treatment of skin and soft tissue infections (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.07-2.43). Comparators were as effective as vancomycin in the intent-to-treat population (OR, 1.08; 95% CI, 0.98-1.18) but were more effective in the clinically evaluable population (OR, 1.14; 95% CI, 1.02-1.27) when all infections were pooled. When available data from all trials were pooled, no differences were noted when patients with febrile neutropenia (OR, 1.07; 95% CI, 0.82-1.39), pneumonia (OR, 1.10; 95% CI, 0.87-1.37), bacteremia (OR, 1.05; 95% CI, 0.76-1.45), and skin and soft tissue infections (OR, 1.11; 95% CI, 0.89-1.39) were studied. Comparators were more effective in open-label (OR, 1.28; 95% CI, 1.08-1.50) but not in double-blind trials (OR, 1.04; 95% CI, 0.90-1.20). Total adverse events attributed to studied antibiotics (OR, 1.07; 95% CI, 0.90-1.28) and patients withdrawn from trials (OR, 0.86; 95% CI, 0.68-1.09) were similar in the compared groups. Mortality was not different between vancomycin and comparator antibiotics when all trials were included in the analysis (OR, 1.09; 95% CI, 0.96-1.23). Comparators were associated with higher mortality in open-label (OR, 1.27; 95% CI, 1.05-1.54) but not double-blind trials (OR, 0.96; 95% CI, 0.80-1.14).

CONCLUSION

On the basis mainly of data from open-label trials, vancomycin is a treatment choice that is as effective as other available antibiotics for patients with gram-positive infections. Study design seems to make a major contribution to the outcome.

Application of SBDD to the discovery of new antibacterial drugs

The emergence of bacteria that are multiply resistant to commonly used antibiotics has created the medical need for novel classes of antibacterial agents. The unique challenges to the discovery of new antibacterial drugs include the following: spectrum, selectivity, low emergence of new resistance, and high potency. With the emergence of genomic information, dozens of antibacterial targets have been pursued over the last 2 decades often using SBDD. This chapter reviews the application of structure-based drug design approaches on a selected group of antibacterial targets (DHFR, DHNA, PDF, and FabI) where significant progress has been made. We compare and contrast the different approaches and evaluate the results in terms of the biological profiles of the leads produced. Several common themes have emerged from this survey, resulting in a set of recommendations.

An overview of foot infections in diabetes

Patients with diabetes are prone to ulcerations of the lower extremities, frequently complicated by infection, and are then reliant upon their caregivers for preservation of their limbs without the dreaded outcome of amputation. The enormous tolls of foot infections in diabetes, in terms of both health-related quality of life issues and associated economic burdens, have only been fully realized within the last few decades, and it is anticipated that these burdens will only increase over time. Early and appropriate antibiotic treatment targeting the most likely etiologic pathogens is a cornerstone of management of foot infections in diabetes, but these decisions are now complicated by the emergence of resistant organisms, particularly methicillin-resistant Staphylococcus aureus and multidrug-resistant Gram-negative species. This review will examine the impact of foot infections in diabetes and the overall care and management of the diabetes patient with foot infection, including the potential value of emerging antibiotic therapies within the milieu of antibiotic resistance.

Diabetic foot infections: microbiological aspects, current and future antibiotic therapy focusing on methicillin-resistant Staphylococcus aureus

Diabetic patients are at increased risk of complicated skin, skin structure and bone infections including infections of diabetic foot ulcerations (DFU). Analyses of epidemiology and microbial pathogenicity show that staphylococci seem to be predestined to induce such infections. In addition, multidrug resistance particularly due to an increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) seems to be the challenge for effective antibiotic therapy. With regard to infections with MRSA, classical agents like vancomycin, linezolid, fosfomycin or trimethroprim-sulphametoxazol might be agents of choice in DFU. New-generation drugs including broad-spectrum tetracyclines like tigecycline, first and second generation of cyclic lipopeptides, anti-MRSA β-lactams including ceftobiprole and anti-MRSA antibodies are developed or in progress and the hope for the future.

Cost-effectiveness analysis of linezolid, daptomycin, and vancomycin in methicillin-resistant Staphylococcus aureus: complicated skin and skin structure infection using Bayesian methods for evidence synthesis

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) complicated skin and skin structure infection (cSSSI) is a prominent infection encountered in hospital and outpatient settings that is associated with high resource use for the health-care system.

OBJECTIVE

A decision analytic (DA) model was developed to evaluate the cost-effectiveness analysis (CEA) of linezolid, daptomycin, and vancomycin in MRSA cSSSI.

METHODS

Bayesian methods for evidence synthesis were used to generate efficacy and safety parameters for a DA model using published clinical trials. CEA was done from the US health-care perspective. Efficacy was defined as a successfully treated patient at the test of cure without any adverse reaction. Primary outcome was the incremental cost-effectiveness ratio between linezolid and vancomycin, daptomycin and vancomycin, and linezolid and daptomycin in MRSA cSSSI. Univariate and probabilistic sensitivity analyses were performed to test the robustness of the model.

RESULTS

The total direct costs of linezolid, daptomycin, and vancomycin were $18,057, $20,698, and $23,671, respectively. The cost-effectiveness ratios for linezolid, daptomycin, and vancomycin were $37,604, $44,086, and $52,663 per successfully treated patient, respectively. Linezolid and daptomycin were dominant strategies compared to vancomycin. However, linezolid was dominant when compared to daptomycin. The model was sensitive to the duration of daptomycin and linezolid treatment.

CONCLUSION

Linezolid and daptomycin are potentially cost-effective based on the assumptions of the DA model; however, linezolid appears to be more cost-effective compared to daptomycin and vancomycin for MRSA cSSSIs.