Ceftobiprole versus daptomycin in Staphylococcus aureus bacteremia: a novel protocol for a double-blind, Phase III trial

Real-World Experience of Ceftobiprole for Community- and Hospital-Acquired Pneumonia from a Stewardship Perspective

Ceftobiprole is a fifth-generation cephalosporin approved by European and American regulatory agencies for the treatment of community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP). Ceftobiprole administration is useful in severe CAP as well as HAP where the potential is to save other β-lactams including carbapenems or linezolid/vancomycin in clinical practice. The aim of this study was to report the real-world evidence of ceftobiprole in patients with CAP and HAP in a single center. In this retrospective study, we included 159 patients with CAP or HAP: 105 (66%) had CAP and 54 (34%) had HAP. The median age was 70 years (IQR 60-77), the median Charlson Comorbidity Index was 5 (IQR 3-7.5) and baseline INCREMENT ESBL score was 8 (IQR 6-11). Ceftobiprole was mostly given as a combination treatment (77%) or as a carbapenem-sparing strategy (44%). There were no differences in mortality between shorter and longer duration of treatment (<7 days compared with ≥7 days (HR 1.02, C.I. 0.58-1.77, p = 0.93) or between first-line (HR 1.00, C.I. 0.46-2.17, p = 0.989) and second-line therapy. Ceftobiprole use in CAP or HAP in the real world is effective as a first- and second-line treatment as well as a carbapenem-sparing strategy. Further studies are needed to explore the full potential of ceftobiprole, including its real-world use in antimicrobial stewardship programs.

Ceftobiprole for Treatment of Complicated Staphylococcus aureus Bacteremia

BACKGROUND

Ceftobiprole is a cephalosporin that may be effective for treating complicated Staphylococcus aureus bacteremia, including methicillin-resistant S. aureus.

METHODS

In this phase 3, double-blind, double-dummy, noninferiority trial, adults with complicated S. aureus bacteremia were randomly assigned in a 1:1 ratio to receive ceftobiprole at a dose of 500 mg intravenously every 6 hours for 8 days and every 8 hours thereafter, or daptomycin at a dose of 6 to 10 mg per kilogram of body weight intravenously every 24 hours plus optional aztreonam (at the discretion of the trial-site investigators). The primary outcome, overall treatment success 70 days after randomization (defined as survival, bacteremia clearance, symptom improvement, no new S. aureus bacteremia-related complications, and no receipt of other potentially effective antibiotics), with a noninferiority margin of 15%, was adjudicated by a data review committee whose members were unaware of the trial-group assignments. Safety was also assessed.

RESULTS

Of 390 patients who underwent randomization, 387 (189 in the ceftobiprole group and 198 in the daptomycin group) had confirmed S. aureus bacteremia and received ceftobiprole or daptomycin (modified intention-to-treat population). A total of 132 of 189 patients (69.8%) in the ceftobiprole group and 136 of 198 patients (68.7%) in the daptomycin group had overall treatment success (adjusted difference, 2.0 percentage points; 95% confidence interval [CI], -7.1 to 11.1). Findings appeared to be consistent between the ceftobiprole and daptomycin groups in key subgroups and with respect to secondary outcomes, including mortality (9.0% and 9.1%, respectively; 95% CI, -6.2 to 5.2) and the percentage of patients with microbiologic eradication (82.0% and 77.3%; 95% CI, -2.9 to 13.0). Adverse events were reported in 121 of 191 patients (63.4%) who received ceftobiprole and 117 of 198 patients (59.1%) who received daptomycin; serious adverse events were reported in 36 patients (18.8%) and 45 patients (22.7%), respectively. Gastrointestinal adverse events (primarily mild nausea) were more frequent with ceftobiprole.

CONCLUSIONS

Ceftobiprole was noninferior to daptomycin with respect to overall treatment success in patients with complicated S. aureus bacteremia. (Funded by Basilea Pharmaceutica International and the U.S. Department of Health and Human Services; ERADICATE ClinicalTrials.gov number, NCT03138733.).

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) in Canada: treatment update and the role of new IV antimicrobials

INTRODUCTION

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) continue to be common infections causing significant morbidity and mortality worldwide. The timely initiation of empiric antimicrobial therapy is essential. In this paper, we provide a focused expert opinion on the current and potential empiric antimicrobial treatment options in HABP and VABP in Canada influenced by antimicrobial resistance impacting the use of older agents as well as available new intravenous (IV) antimicrobials.

AREAS COVERED

The authors discuss treatment options for HABP and VABP in Canada. In addition, we focus on the potential role of new IV antimicrobials recently introduced to Canada. A literature search of HABP and VABP treatments was performed via PubMed (up to March 2023), using the following key words: monotherapy, combination therapy, aminoglycosides, carbapenems, cephalosporins, fluoroquinolones, penicillins as well as amoxicillin/clavulanate, ceftobiprole, ceftolozane/tazobactam, dalbavancin, and fosfomycin.

EXPERT OPINION

Empiric antimicrobial treatment for HABP and VABP in Canada continues to focus on both the severity of illness and the presence/absence of patient risk factors for antimicrobial resistance. The role of new IV antimicrobials in the empiric treatment for HABP and VABP depends on their antimicrobial activity and published data on efficacy and safety and influenced by Health Canada-approved indications.

Optimal drug therapy for Staphylococcus aureus bacteraemia in adults

PURPOSE OF REVIEW

Staphylococcus aureus is a significant human pathogen, causing a variety of infections, from skin and soft tissue infections to endocarditis, bone and joint infections and deep tissue abscesses. Mortality from S. aureus bacteraemia remains high, without major therapeutic advances in recent decades.

RECENT FINDINGS

In recent years, optimized dosing of antibiotics is increasingly being recognized as a cornerstone of management for severe infections including S. aureus bacteraemia. This comprehensive review details the pharmacokinetics/pharmacodynamics (PK/PD) targets for commonly used antistaphylococcal antibiotics and the doses predicted to achieve them in clinical practice. Recent advances in dosing of teicoplanin and use of cefazolin in CNS infections and findings from combination therapy studies are discussed. Drug exposure relationships related to toxicity are also detailed.

SUMMARY

This review details the different PK/PD targets for drugs used to treat S. aureus bacteraemia and how to apply them in various scenarios. The drug doses that achieve them, and the risks of toxicity are also provided.

Efficacy of ceftobiprole in a murine model of bacteremia and disseminated infection

Introduction. Ceftobiprole is an advanced-generation broad-spectrum parenteral cephalosporin with activity against MSSA and MRSA.Gap Statement. Ceftobiprole is not currently approved for use to treat S. aureus bacteremia and phase three clinical trials are taking place. Drug approval requires further pre-clinical evidence to support this new indication.Aim. The aim of this study was to evaluate the efficacy of ceftobiprole at the human equivalent efficacious exposure (considering a 500 mg q8h dosing regimen infused over 2 h) against MSSA and MRSA strains in a neutropenic murine model of bacteremia and disseminated infection.Methodology. Two bioluminescent-tagged strains (one MSSA and one MRSA strain) were selected based on their in vitro susceptibility and in vivo growth profiles. Bacterial c.f.u. counts in the blood, lung, kidney, and liver were determined 48 h post-infection or after death. The bioluminescent-tag allowed the visualization of the real-time effects of ceftobiprole therapy compared to the natural progression of the infection in untreated controls.Results. Treatment with ceftobiprole resulted in a significant reduction of the bacterial load with the bioluminescence reduced by 2-log units and bacterial c.f.u. counts reduced by 3- to 6-log units, depending on the organ and bacterial strain. Survival was 100 % in the ceftobiprole-treated group compared to only 0-20 % survival in the untreated control animals for both strains tested.Conclusion. These results suggest that treatment with ceftobiprole using a 500 mg q8h dosing regimen studied in several successful phase three trials, has potential as an antibiotic therapy to treat bacteremia and associated disseminated infections caused by either methicillin-susceptible or methicillin-resistant strains of S. aureus.

Ceftobiprole Medocaril Is an Effective Post-Exposure Treatment in the Fischer 344 Rat Model of Pneumonic Tularemia

Francisella tularensis subspecies tularensis is a category-A biothreat agent that can cause lethal tularemia. Ceftobiprole medocaril is being explored as a medical countermeasure for the treatment of pneumonic tularemia. The efficacy of ceftobiprole medocaril against inhalational tularemia was evaluated in the Fischer 344 rat model of infection. The dose was expected to be effective against F. tularensis isolates with ceftobiprole minimum inhibitory concentrations ≤0.5 µg/mL. Animals treated with ceftobiprole medocaril exhibited a 92% survival rate 31 days post-challenge, identical to the survival of levofloxacin-treated rats. By comparison, rats receiving placebo experienced 100% mortality. Terminally collected blood, liver, lung, and spleen samples confirmed disseminated F. tularensis infections in most animals that died prior to completing treatments (placebo animals and a rat treated with ceftobiprole medocaril), although levels of bacteria detected in the placebo samples were significantly elevated compared to the ceftobiprole-medocaril-treated group geometric mean. Furthermore, no evidence of infection was detected in any rat that completed ceftobiprole medocaril or levofloxacin treatment and survived to the end of the post-treatment observation period. Overall, survival rates, body weights, and bacterial burdens consistently demonstrated that treatment with ceftobiprole medocaril is efficacious against otherwise fatal cases of pneumonic tularemia in the rat model.

Which trial do we need? Next-generation sequencing to individualize therapy in Staphylococcus aureus bacteraemia

We propose a two-stage clinical trial in patients with Staphylococcus aureus bacteremia (SAB). In Stage 1 we will evaluate metagenomic next generation sequencing from blood as a quantitative biological surrogate for clinical endpoint in patients with SAB, similar to quantitative HIV viral load in HIV-infected patients. In Stage 2, we will conduct a randomized controlled trial to individualize duration of antibiotic therapy for based upon the presence of S. aureus genetic material in patients’ blood. The proposed study addresses two critical aspects of treatment of patients with SAB: the identification of a surrogate biological endpoint for future clinical trials, and a new approach by which to individualize patient management.

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.

Current and emerging drug treatment strategies to tackle invasive community-associated methicillin-resistant Staphylococcus aureus (MRSA) infection: what are the challenges?

INTRODUCTION

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections represent a leading cause of purulent skin and soft tissue infections in some geographical regions. Traditionally, 'old antibiotics' such as trimethoprim-sulfamethoxazole, tetracyclines, clindamycin, chloramphenicol,vancomycin, and teicoplanin have been used to treat these infections, but these were often associated with low efficacy and excessive side effects and toxicity, especially nephrotoxicity. Along with the development of new compounds, the last decade has seen substantial improvements in the management of CA-MRSA infections.

AREAS COVERED

In this review, the authors discuss the current and emerging drug treatment strategies to tackle invasive CA-MRSA infections. Articles reported in this review were selected from through literature searches using the PubMed database.

EXPERT OPINION

The availability of new drugs showing a potent in vitro activity against CA-MRSA represents a unique opportunity to face the threat of resistance while potentially reducing toxicity. All these compounds represent promising options to enhance our antibiotic armamentarium. However, data regarding the use of these new drugs in real-life studies are limited and their best placement in therapy and in terms of optimization of medical resources and balance of cost-effectiveness requires further investigation.

Study of Degradation Kinetics and Structural Analysis of Related Substances of Ceftobiprole by HPLC with UV and MS/MS Detection

Ceftobiprole is a novel β-lactam antibiotic, active against methicillin-resistant Staphylococcus aureus, vancomycin-resistant S. aureus and penicillin-resistant Streptococcus pneumoniae. To artificially generate potential degradation products (DPs) of ceftobiprole that may be formed under relevant storage conditions, acidic, alkaline, oxidative, photolytic and thermolytic stress tests were performed in both solution and solid state. A novel selective HPLC method was developed for the separation of ceftobiprole from its DPs and synthesis by-products (SBPs) using Kinetex Biphenyl column, ammonium acetate buffer pH 5.8 and acetonitrile. The kinetic studies demonstrated the low stability of ceftobiprole in alkaline solution, in the presence of an oxidising agent and under irradiation with near UV. In the solid state, ceftobiprole underwent oxidation when the powder was irradiated with visible light and UV. Based on mass spectroscopic analysis, 13 new structural formulas of SBPs and DPs were proposed, along with molecular formulas for three other DPs obtained in solution and four oxidative DPs characteristic of solid-state degradation.

Persistent Methicilin-Resistant Staphylococcus aureus Bacteremia: Resetting the Clock for Optimal Management

A positive follow-up blood culture for methicillin-resistant Staphylococcus aureus (MRSA) while on seemingly appropriate therapy is a common and ominous development. However, the definition and management of persistent MRSA bacteremia is unstandardized. In this Opinion Paper, we identify the presence of bacteremia for > 1 calendar day as a "worry point" that should trigger an intensive diagnostic evaluation to identify metastatic infection sites. Next, we define the duration of MRSA bacteremia that likely constitutes antibiotic failure and outline a potential management algorithm for such patients. Finally, we propose pragmatic clinical trial designs to test treatment strategies for persistent MRSA bacteremia.

Vancomycin, Daptomycin, Antistaphylococcal β-Lactam, and Trimethoprim-Sulfamethoxazole Monotherapy and Combination Therapy in the Management of Methicillin-Resistant Staphylococcus aureus: A Network Meta-Analysis

Objective: The aim was to evaluate the efficacy and safety of vancomycin or daptomycin (VAN/DAP), antistaphylococcal β-lactam (ASBL), trimethoprim-sulfamethoxazole (TMP-SMX), and combination therapy of VAN/DAP + ASBL in the management of methicillin-resistant Staphylococcus aureus (MRSA). Methods: Databases including PubMed, Cochrane Library, Embase database, and google scholar were searched on 1 September 2021. The randomized control trials (RCTs) and comparable clinical studies of VAN/DAP, VAN/DAP + ASBL, ASBL, and TMP-SMX in the management of MRSA were identified. A network meta-analysis was conducted with STATA 14.0. Results: Seven RCTs and two matched cohorts with 1,048 patients were included in the analysis. The pooled results showed that VAN/DAP + ASBL had a significantly lower rate of persistent bacteremia >3 days than VAN/DAP alone [OR:0.46, 95%CI (0.26, 0.81), p < 0.001]. No obvious differences were observed in the outcomes of all-cause mortality, relapsed bacteremia, microbiological treatment failure, embolic or metastatic infection, and total adverse events. However, the ranking results showed that VAN/DAP + ASBL had slightly better efficacy (all-cause mortality, persistent bacteremia >3 days, duration of bacteremia, microbiological treatment failure, and relapsed bacteremia) but slightly higher adverse events than VAN/DAP alone. No obvious differences in the comparisons of VAN/DAP vs. ASBL, and VAN/DAP vs TMP-SMX in the analyzed outcomes. The ranking results revealed that ASBL and TMP-SMX did not have better efficacy or lower adverse events compared with the treatment of VAN/DAP. Conclusion: The efficacy of VAN/DAP + ASBL was slightly but not significantly better than VAN/DAP alone in the management of MRSA.

Investigational agents for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia: progress in clinical trials

INTRODUCTION

Bacteremia caused by Staphylococcus aureus is common. Cases caused by methicillin-resistant S. aureus (MRSA) are particularly formidable and often lethal. The mortality associated with MRSA bacteremia has not significantly decreased over the past couple of decades and concerns regarding efficacy and toxicity of standard therapy highlight the need for novel agents and new therapeutic approaches.

AREAS COVERED

This paper explores clinical trials investigating novel therapeutic approaches to S. aureus bacteremia. There is a special focus on MRSA bacteremia. Monotherapy and combination therapies and novel antimicrobials and adjunctive therapies that are only recently being established for therapeutic use are discussed.

EXPERT OPINION

The unfavorable safety profile of combination antimicrobial therapy in clinical trials has outweighed its benefits. Therefore, future investigation should focus on optimizing duration and de-escalation protocols. Antibody and bacteriophage lysin-based candidates have mostly been limited to safety trials, but progress with these agents is demonstrated through a lysin-based agent receiving a phase III trial. Antibiotics indicated for use in treating MRSA skin infections see continued investigation as treatments for MRSA bacteremia despite the difficulty of completing trials in this patient population. Promising agents include dalbavancin, ceftobiprole, ceftaroline, and exebacase.

OUP accepted manuscript

Objectives

To evaluate the susceptibility to ceftobiprole of clinical bacterial isolates obtained from hospitalized patients in Europe.

Methods

A total of 20 000 non-duplicate bacterial isolates were collected in 2016–19 from patients with documented infections at medical centres located in 17 countries in Europe. Bacterial identification was confirmed and susceptibility to ceftobiprole and comparator agents was tested using the EUCAST broth microdilution methodology and interpretive criteria by a central microbiology laboratory.

Results

Of the 20 000 isolates, 10 007 (50.0%) were Gram-positive and 9993 (50.0%) were Gram-negative. The most common species was Staphylococcus aureus (35.0%), followed by Streptococcus pneumoniae (15.0%), Klebsiella pneumoniae (11.1%), Pseudomonas aeruginosa (11.0%), Escherichia coli (9.7%) and Haemophilus influenzae (3.0%). Overall, 99.7% (6981/7000) of S. aureus, including 99.5% (3483/3502) of MRSA, 97.8% (2941/3007) of S. pneumoniae, 100% (605/605) of H. influenzae and 76.3% (5492/7197) of Enterobacterales isolates were susceptible to ceftobiprole. Susceptibility to ceftobiprole was higher for isolates from northern and western Europe as compared with eastern and southern Europe.

Conclusions

Ceftobiprole continues to exhibit potent and broad-spectrum activity against Gram-positive and Gram-negative clinical isolates from Europe, and as expected, with a slight north-to-south and west-to-east susceptibility gradient.

Pharmacokinetics and Safety of Ceftobiprole in Pediatric Patients

BACKGROUND

Ceftobiprole, the active moiety of the prodrug ceftobiprole medocaril, is an advanced-generation, broad-spectrum, intravenous cephalosporin, which is currently approved for the treatment of adults with hospital-acquired or community-acquired pneumonia.

METHODS

Noncompartmental pharmacokinetics and safety were analyzed from 2 recently completed pediatric studies, a single-dose, phase 1 study in neonates and infants up to 3 months of age (7.5 mg/kg) and a phase 3 study in patients 3 months to 17 years of age with pneumonia (10-20 mg/kg with a maximum of 500 mg per dose every 8 hours for up to 14 days).

RESULTS

Total ceftobiprole plasma concentrations peaked at the end of infusion. Half life (median ranging from 1.9 to 2.9 hours) and overall exposure (median AUC ranging from 66.6 to 173 μg•h/mL) were similar to those in adults (mean ± SD, 3.3 ± 0.3 hours and 102 ± 11.9 μg•h/mL, respectively). Calculated free-ceftobiprole concentrations in the single-dose study remained above a minimum inhibitory concentration (MIC) of 4 mg/L (fT > MIC of 4 mg/L) for a mean of 5.29 hours after dosing. In the pneumonia study, mean fT > MIC of 4 mg/L was ≥5.28 hours in all dose groups. Ceftobiprole was well tolerated in both studies.

CONCLUSIONS

Pharmacokinetic parameters of ceftobiprole characterized in the pediatric population were within the range of those observed in adults. In the pneumonia study, the lowest percentage of the dosing interval with fT > MIC of 4 mg/L was 50.8%, which suggests that pharmacokinetic-pharmacodynamic target attainment can be sufficient in pediatric patients. Ceftobiprole was well tolerated.

Optimizing Ceftobiprole Dosage in Pediatric Patients: A Model-Based Approach

Ceftobiprole is an advanced-generation cephalosporin for intravenous administration with activity against Gram-positive and Gram-negative organisms. A population pharmacokinetic (PK) model characterizing the disposition of ceftobiprole in plasma using data from patients in three pediatric studies was developed. Model-based simulations were subsequently performed to assist in dose optimization for the treatment of pediatric patients with hospital-acquired or community-acquired pneumonia. The population PK data set comprised 518 ceftobiprole plasma concentrations from 107 patients from 0 (birth) to 17 years of age. Ceftobiprole PK was well described by a three-compartment model with linear elimination. Ceftobiprole clearance was modeled as a function of glomerular filtration rate; other PK parameters were scaled to body weight. The final population PK model provided a robust and reliable description of the PK of ceftobiprole in the pediatric study population. Model-based simulations using the final model suggested that a ceftobiprole dose of 15 mg/kg of body weight infused over 2 h and administered every 12 h in neonates and infants <3 months of age or every 8 h in older pediatric patients would result in a ceftobiprole exposure consistent with that in adults and good pharmacokinetic-pharmacodynamic target attainment. The dose should be reduced to 10 mg/kg every 12 h in neonates and infants <3 months of age who weigh <4 kg to avoid high exposures. Extended intervals and reduced doses may be required for pediatric patients older than 3 months of age with renal impairment.

A post hoc analysis of two Phase III trials showing the efficacy and tolerability of ceftobiprole in East Asian patients

Aim: To evaluate the efficacy and safety of ceftobiprole in patients from East Asia. Materials & methods: A post hoc analysis was conducted of two randomized, double-blind, Phase III studies in patients with community- or hospital-acquired pneumonia. Results: Findings for East Asian patients were consistent with the overall study populations. A trend toward higher microbiological eradication rates and numerically lower rates of all-cause mortality were reported for ceftobiprole versus comparators (all-cause mortality [intent-to-treat]: community-acquired pneumonia, 1.5 vs 2.8%; hospital-acquired pneumonia excluding ventilator-associated pneumonia, 5.9 vs 11.4%). The incidence of adverse events was similar between treatment groups. Conclusion: This post hoc analysis supports the efficacy and tolerability of ceftobiprole in East Asian patients. ClinicalTrials.gov trial identifiers: NCT00326287, NCT00210964, NCT00229008.

Efficacy and safety of ceftobiprole in patients aged 65 years or older: a post hoc analysis of three Phase III studies

Aim: To evaluate the efficacy and safety of ceftobiprole in patients aged ≥65 years. Materials & methods: We conducted a post hoc analysis of three randomized, double-blind, Phase III studies in patients with acute bacterial skin and skin structure infections, community-acquired pneumonia and hospital-acquired pneumonia. Results: Findings for patients aged ≥65 years (n = 633) were consistent with those for the overall study populations, although a trend toward improved outcomes was reported in some subgroups, for example, patients aged ≥75 years with community-acquired pneumonia were more likely to achieve an early clinical response with ceftobiprole than comparator (treatment difference 16.3% [95% CI:1.8-30.8]). The safety profile was similar between treatment groups in all studies. Conclusion: This analysis further supports the efficacy and safety of ceftobiprole in older patients with acute bacterial skin and skin structure infections or pneumonia. Clinicaltrials.gov trial identifiers: NCT03137173, NCT00326287, NCT00210964, NCT00229008.

Ceftobiprole Perspective: Current and Potential Future Indications

Ceftobiprole combines an excellent spectrum for community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) pathogens, with a low/medium MDR risk, and the β-lactams' safety in frail patients admitted to the hospital in internal medicine wards which may be at high risk of adverse events by anti-MRSA coverage as oxazolidinones or glycopeptides. We aimed to report the available evidence regarding ceftobiprole use in pneumonia and invasive bacterial infections, shedding light on ceftobiprole stewardship. The clinical application and real-life experiences of using ceftobiprole for bloodstream infections, including infective endocarditis, are limited but nevertheless promising. In addition, extended-spectrum ceftobiprole activity, including Enterococcus faecalis, Enterobacteriaceae, and Pseudomonas aeruginosa, has theoretical advantages for use as empirical therapy in bacteremia potentially caused by a broad spectrum of microorganisms, such as catheter-related bacteremia. In the future, the desirable approach to sepsis and severe infections will be administered to patients according to their clinical situation, the intrinsic host characteristics, the susceptibility profile, and local epidemiology, while the "universal antibiotic strategy" will no longer be adequate.

Real-life experience with ceftobiprole in Canada: Results from the CLEAR (CanadianLEadership onAntimicrobialReal-life usage) registry

OBJECTIVES

Ceftobiprole is an advanced-generation cephalosporin with a favourable safety profile. Published data on the clinical use of ceftobiprole are limited. We report use of ceftobiprole in Canadian patients using data captured by the CLEAR registry.

METHODS

The CLEAR registry uses the web-based research data management program REDCap™ (online survey) to facilitate clinicians entering details associated with their clinical experiences using ceftobiprole.

RESULTS

Data were available for 38 patients treated with ceftobiprole. The most common infections treated were endocarditis (42.1% of patients), bone and joint infection (23.7%) and hospital-associated bacterial pneumonia (15.8%). 92.1% of patients had bacteraemia and 21.1% were in intensive care. Ceftobiprole was used because of failure of (71.1%), resistance to (18.4%) or adverse effects from (10.5%) previously prescribed antimicrobial agents. Ceftobiprole was primarily used as directed therapy for methicillin-resistant Staphylococcus aureus (MRSA) infections (94.7% of patients). Ceftobiprole susceptibility testing was performed on isolates from 47.4% of patients. It was used concomitantly with daptomycin in 55.3% of patients and with vancomycin in 18.4% of patients. Treatment duration was primarily >10 days (65.8% of patients) with microbiological success in 97.0% and clinical success in 84.8% of patients. 2.6% of patients had gastrointestinal adverse effects.

CONCLUSION

In Canada to date, ceftobiprole is used as directed therapy to treat a variety of severe infections caused by MRSA. It is primarily used in patients failing previous antimicrobials, is frequently added to, and thus used in combination with daptomycin or vancomycin with high microbiological and clinical cure rates and an excellent safety profile.

No Evidence for Ceftobiprole-Induced Immune Hemolytic Anemia in Three Phase 3 Clinical Trials

Purpose

Drug-induced immune hemolytic anemia (DIIHA) is a rare but serious adverse event associated with a number of drugs, including second- and third-generation cephalosporins. A positive direct antiglobulin test (DAT) is a reliable finding in DIIHA, but positive results without evidence of hemolysis can occur, particularly in hospitalized patients. There have been no reports of hemolytic anemia in four previous Phase 3 trials or from post-marketing surveillance of the advanced-generation, broad-spectrum cephalosporin, ceftobiprole. The aim of this analysis was to review the incidence of positive DAT results and any evidence of hemolytic anemia from three recent Phase 3 trials of ceftobiprole.

Patients and Methods

Patients were enrolled in three Phase 3 randomized controlled trials: 94 pediatric patients with pneumonia received ceftobiprole in the BPR-PIP-002 trial; 335 adults with acute bacterial skin and skin structure infections received ceftobiprole in the TARGET trial; and 201 adults with Staphylococcus aureus bacteremia have been randomized 1:1 to ceftobiprole or daptomycin ± aztreonam in the ongoing ERADICATE trial. In all three trials, DAT results were obtained at baseline, and follow-up tests were performed either at the test of cure (TOC) visit (BPR-PIP-002), end-of-treatment (EOT) visit (TARGET), or both EOT and post-treatment Day 70 visits (ERADICATE).

Results

In the BPR-PIP-002 trial, five patients (all ceftobiprole treated) had a documented negative DAT result at baseline followed by a positive result at the TOC visit. One patient in the ongoing, blinded ERADICATE trial had a positive DAT result at both baseline and EOT. Results from other laboratory investigations showed no evidence of hemolytic anemia in these patients. No positive DAT results were reported in the TARGET trial.

Conclusion

No evidence of hemolytic anemia associated with ceftobiprole was observed in either adults or children across several indications in this analysis of three large Phase 3 trials.

Ceftobiprole for Treatment of MRSA Blood Stream Infection: A Case Series

While methicillin-resistant Staphylococcus aureus (MRSA) bacteremia has poor outcomes, we describe our experience with Ceftobiprole mainly as a combination therapy for the treatment of MRSA bacteremia. All the cases of MRSA bacteremia in our center at the King Abdulaziz Medical City (KAMC), Riyadh, that had undergone Ceftobiprole treatment were included. We had six cases of MRSA bacteremia between 2018 and 2019, secondary to different infectious syndromes including endocarditis. There was a severe infection that required intensive care unit (ICU) admission in four cases. Ceftobiprole is used in combination with vancomycin in four cases. On day 14, all cases had a favorable outcome with microbiological and clinical improvement. However, three patients died after months of suffering from bacteremia from unrelated causes for the infection. The clinical outcome in our series of treatment of MRSA bacteremia using Ceftobiprole was favorable. Further studies for the evaluation of the use of Ceftobiprole in MRSA bacteremia should be encouraged.

A case study on Staphylococcus aureus bacteraemia: available treatment options, antibiotic R&D and responsible antibiotic-use strategies

Objectives

This case study addresses: (i) antibiotic treatment options for Staphylococcus aureus bacteraemia (SAB), for both empirical and targeted therapy; (ii) the current status of and priorities for the antibiotic pipeline to ensure access of effective antibiotics for SAB; and (iii) strategies for responsible antibiotic use relevant to the clinical management of SAB.

Methods

Evidence to address the aims was extracted from the following information sources: (i) EUCAST and CLSI recommendations, summaries of product characteristics (SPCs), antibiotic treatment guidelines and the textbook Kucers’ The Use of Antibiotics; (ii) the www.clinicaltrial.gov database; and (iii) quality indicators for responsible antibiotic use.

Results

Current monotherapy treatment options for SAB include only three drug classes (β-lactams, glycopeptides and lipopeptides), of which two also cover MRSA bacteraemia (glycopeptides and lipopeptides). The analysis of the antibiotic pipeline and ongoing clinical trials revealed that several new antibiotics with S. aureus (including MRSA) coverage were developed in the past decade (2009–19). However, none belonged to a new antibiotic class or had superior effectiveness and their added clinical value for SAB remains to be proven. Responsible antibiotic use for the treatment of SAB was illustrated using 11 quality indicators.

Conclusions

Awareness of the problem of a limited antibiotic arsenal, together with incentives (e.g. push incentives), is needed to steer the R&D landscape towards the development of novel and effective antibiotics for treating SAB. In the meantime, responsible antibiotic use guided by quality indicators should preserve the effectiveness of currently available antibiotics for treating SAB.