Ceftaroline fosamil: a cephalosporin with activity against methicillin-resistant Staphylococcus aureus

In vitro activity of cefoxitin, imipenem, meropenem, and ceftaroline in combination with vaborbactam against Mycobacterium abscessus

Mycobacterium abscessus (MAB) infections pose a growing public health threat. Here, we assessed the in vitro activity of the boronic acid-based β-lactamase inhibitor, vaborbactam, with different β-lactams against 100 clinical MAB isolates. Enhanced activity was observed with meropenem and ceftaroline with vaborbactam (1- and >4-fold MIC50/90 reduction). CRISPRi-mediated blaMAB gene knockdown showed a fourfold MIC reduction to ceftaroline but not the other β-lactams. Our findings demonstrate vaborbactam's potential in combination therapy against MAB infections.

A review of recent advances in the treatment of adults with complicated urinary tract infection

INTRODUCTION

Complicated urinary tract infections (cUTIs) entail diverse clinical conditions that could be managed differently and not necessarily with premature empiric therapy. Since multidrug-resistant organisms (MDROs) are widely spreading worldwide, the possibility of encountering these resistant bacteria is inevitably part of the daily life of physicians who manage cUTIs.

AREAS COVERED

The advances in the management of cUTIs are explored, illustrating: 1) a proposed therapeutical approach to cUTIs within the antimicrobial stewardship context; 2) evidence regarding novel antibiotics targeting MDROs. Evidence research has been performed through MEDLINE/PubMed using appropriate keywords and terms regarding cUTIs published before June 2022.

EXPERT OPINION

Novel antimicrobial drugs are available in the clinicians' armamentarium. Selecting the optimal therapy for suitable patients may be challenging given the multifaceted group of cUTIs. Carbapenems use is widely increasing, the role of old β-lactam/β-lactamase inhibitors is constantly revised, and novel drugs lack real-life studies. Understanding the different ranges of the complexity of patients affected by cUTIs may help select the most suitable antibiotic for every single case. More multicentric observational studies targeting cUTIs are needed to elucidate the appropriate drug based on patient characteristics and presentations, providing stronger recommendations for cases encountered in everyday clinical practice.

Impact on in-hospital mortality of ceftaroline versus standard of care in community-acquired pneumonia: a propensity-matched analysis

The purpose of this study is to evaluate the in-hospital mortality of community-acquired pneumonia (CAP) treated with ceftaroline in comparison with standard therapy. This was a retrospective observational study in two centers. Hospitalized patients with CAP were grouped according to the empiric regimen (ceftaroline versus standard therapy) and analyzed using a propensity score matching (PSM) method to reduce confounding factors. Out of the 6981 patients enrolled, 5640 met the inclusion criteria, and 89 of these received ceftaroline. After PSM, 78 patients were considered in the ceftaroline group (cases) and 78 in the standard group (controls). Ceftaroline was mainly prescribed in cases with severe pneumonia (67% vs. 56%, p = 0.215) with high suspicion of Staphylococcus aureus infection (9% vs. 0%, p = 0.026). Cases had a longer length of hospital stay (13 days vs. 10 days, p = 0.007), while an increased risk of in-hospital mortality was observed in the control group compared to the case group (13% vs. 21%, HR 0.41; 95% CI 0.18 to 0.62, p = 0.003). The empiric use of ceftaroline in hospitalized patients with severe CAP was associated with a decreased risk of in-hospital mortality.

New cephalosporins for the treatment of pneumonia in internal medicine wards

The burden of hospital admission for pneumonia in internal medicine wards may not be underestimated; otherwise, cases of pneumonia are a frequent indication for antimicrobial prescriptions. Community- and hospital-acquired pneumonia are characterized by high healthcare costs, morbidity and non-negligible rates of fatality. The overcoming prevalence of resistant gram-negative and positive bacteria (e.g., methicillin-resistant Staphylococcus aureus, penicillin and ceftriaxone-resistant Streptococcus pneumoniae, extended-spectrum β-lactamases and carbapenemases producing Enterobacteriaceae) has made the most of the first-line agents ineffective for treating lower respiratory tract infections. A broad-spectrum of activity, favourable pulmonary penetration, harmlessness and avoiding in some cases a combination therapy, characterise new cephalosporins such as ceftolozane/tazobactam, ceftobiprole, ceftazidime/avibactam and ceftaroline. We aimed to summarise the role and place in therapy of new cephalosporins in community- and hospital-acquired pneumonia within the setting of internal medicine wards. The “universal pneumonia antibiotic strategy” is no longer acceptable for treating lung infections. Antimicrobial therapy should be individualized considering local antimicrobial resistance and epidemiology, the stage of the illness and potential host factors predisposing to a high risk for specific pathogens.

Efficacy and Safety of Ceftaroline for the Treatment of Community-Acquired Pneumonia: A Systemic Review and Meta-Analysis of Randomized Controlled Trials

This study aimed to compare the clinical efficacy and safety of ceftaroline with those of ceftriaxone for treating community-acquired pneumonia (CAP). The PubMed, Cochrane Library, Embase, and clinicalTrials.gov databases were searched until April 2019. This meta-analysis only included randomized controlled trials (RCTs) that evaluated ceftaroline and ceftriaxone for the treatment of CAP. The primary outcome was the clinical cure rate, and the secondary outcome was the risk of adverse events (AEs). Five RCTs were included. Overall, at the test of cure (TOC), the clinical cure rate of ceftaroline was superior to the rates of ceftriaxone for the treatment of CAP (modified intent-to-treat population (MITT) population, odds ratio (OR) 1.61, 95% confidence interval (CI) 1.31–1.99, I² = 0%; clinically evaluable (CE) population, OR 1.38, 95% CI 1.07–1.78, I² = 14%). Similarly, the clinical cure rate of ceftaroline was superior to that of ceftriaxone at the end of therapy (EOT) (MITT population, OR 1.57, 95% CI 1.16–2.11, I² = 0%; CE population, OR 1.64, 95% CI 1.15–2.33, I² = 0%). For adult patients, the clinical cure rate of ceftaroline remained superior to that of ceftriaxone at TOC (MITT population, OR 1.66, 95% CI 1.34–2.06, I² = 0%; CE population, OR 1.39, 95% CI 1.08–1.80, I² = 30%) and at EOT (MITT population, OR 1.64, 95% CI 1.20–2.24, I² = 0%; CE population, OR 1.65, 95% CI 1.15–2.36, I² = 0%). Ceftaroline and ceftriaxone did not differ significantly in the risk of serious AEs, treatment-emergent AEs, and discontinuation of the study drug owing to an AE. In conclusion, the clinical efficacy of ceftaroline is similar to that of ceftriaxone for the treatment of CAP. Furthermore, this antibiotic is as tolerable as ceftriaxone.

Ceftaroline Efficacy and Safety in Treatment of Complicated Skin and Soft Tissue Infection: A Systemic Review and Meta-Analysis of Randomized Controlled Trials

This study aims to assess the clinical efficacy and safety of ceftaroline for the treatment of complicated skin and skin structure infections (cSSSIs) in adult patients through meta-analysis. PubMed, Embase, ClinicalTrials.gov, and Cochrane databases were searched up to April 2019. Only randomized controlled trials (RCTs) that evaluated ceftaroline and other comparators for treating cSSSIs in adult patients were included. The primary outcome was the clinical cure rate, whereas the secondary outcomes were clinical failure rate, microbiological eradication rate, relapse rate, and risk of an adverse event (AE). Five RCTs were included. Overall, ceftaroline had a clinical cure rate similar to comparators in the treatment of cSSSIs in the modified intent-to-treat population (risk ratio (RR), 1.00; 95% confidence interval (CI), 0.97–1.04; I² = 0%) and in the clinically evaluable population (RR, 1.00; 95% CI, 0.97–1.03; I² = 0%). In addition, no significant difference was observed between ceftaroline and comparators for the treatment of infection with Staphylococcusaureus (RR, 1.01; 95% CI, 0.98–1.05; I² = 0%), methicillin-resistant S. aureus (RR, 0.99; 95% CI, 0.94–1.05; I² = 0%), methicillin-susceptible S. aureus (RR, 1.01; 95% CI, 0.96–1.06; I² = 26%), Streptococcus spp. (RR, 1.07; 95% CI, 0.92–1.24; I² = 73%), and Gram-negative bacteria (RR, 0.94; 95% CI, 0.83–1.08; I² = 0%). Furthermore, ceftaroline had a similar rate of microbiological eradication (92.2% vs. 92.6%, RR, 1.00; 95% CI, 0.97–1.03; I² = 9%) and relapse (6.9% vs. 9.1%, RR, 0.48; 95% CI, 0.14–1.74; I² = 0%) as comparators. Finally, the risks of treatment-emergent AEs (RR, 0.96; 95% CI, 0.88–1.05; I² = 0%), serious AEs (RR, 1.03; 95% CI, 0.63–1.68; I² = 0%), and discontinuation of study drug due to an AE (RR, 0.86; 95% CI, 0.50–1.49; I² = 34%) did not differ significantly between ceftaroline and comparators. In conclusion, the clinical efficacy of ceftaroline is as high as that of comparators in the treatment of cSSSIs in adult patients, and this antibiotic is well tolerated like the comparators.

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.

In vitro ceftaroline combinations against meticillin-resistant Staphylococcus aureus

We studied in vitro ceftaroline combinations against 61 meticillin-resistant Staphylococcus aureus isolates; 18 of them were also resistant to linezolid, using overlapping E-test method. Daptomycin-ceftaroline combination obtained lower fractional inhibitory concentration values, in comparison with those including vancomycin or linezolid against meticillin-resistant S. aureus (P<0.05). All meticillin- and linezolid-resistant S. aureus strains were resistant to ceftaroline; nevertheless, combinations with vancomycin or daptomycin showed higher synergy or addition rates than those with linezolid.

What's new in the treatment of serious MRSA infection?

PURPOSE OF REVIEW

Vancomycin has been the cornerstone of treatment for methicillin-resistant Staphylococcus aureus (MRSA) infections. This review describes new MRSA-active antibiotics that have recently been introduced and highlights emerging resistance.

RECENT FINDINGS

Elevations in the vancomycin minimum inhibitory concentration within the susceptible range are associated with treatment failure and mortality in the treatment of MRSA infections. Ceftaroline and ceftobiprole are anti-MRSA cephalosporins and are noninferior to comparator agents in the treatment of acute bacterial skin and skin structure infections (ABSSSIs) and pneumonia. Tedizolid is more potent than linezolid, has improved pharmacokinetics and reduced toxicity and is active against cfr-containing S. aureus. Telavancin now has approval for treatment of hospital-acquired pneumonia, and recent phase 2 trial data showed similar cure rates in S. aureus bacteremia. Dalbavancin and oritavancin are administered once weekly and are noninferior to comparators for acute bacterial skin and skin structure infections. Resistance has emerged against many new anti-MRSA antimicrobials including ceftaroline. Combination therapy of β-lactams with vancomycin or daptomycin is increasing.

SUMMARY

Several new MRSA-active agents are now approved for use, although much of the data is derived from treatment of acute bacterial skin and skin structure infections or pneumonia. Further studies are required for more invasive infections, such as bacteremia and endocarditis.

Impact of β-lactamase inhibition on the activity of ceftaroline against Mycobacterium tuberculosis and Mycobacterium abscessus

The production of β-lactamases Bla(Mab) and BlaC contributes to β-lactam resistance in Mycobacterium abscessus and Mycobacterium tuberculosis, respectively. Ceftaroline was efficiently hydrolyzed by these enzymes. Inhibition of M. tuberculosis BlaC by clavulanate decreased the ceftaroline MIC from ≥ 256 to 16 to 64 μg/ml, but these values are clinically irrelevant. In contrast, the ceftaroline-avibactam combination should be evaluated against M. abscessus since it inhibited growth at lower and potentially achievable drug concentrations.

Pharmacokinetic/pharmacodynamic analysis to evaluate ceftaroline fosamil dosing regimens for the treatment of community-acquired bacterial pneumonia and complicated skin and skin-structure infections in patients with normal and impaired renal function

In this study, the probability of pharmacokinetic/pharmacodynamic target attainment (PTA) of ceftaroline against clinical isolates causing community-acquired bacterial pneumonia (CABP) and complicated skin and skin-structure infection (cSSSI) in Europe was evaluated. Three dosing regimens were assessed: 600 mg every 12 h (q12 h) as a 1-h infusion (standard dose) or 600 mg every 8 h (q8 h) as a 2-h infusion in virtual patients with normal renal function; and 400 mg q12 h as a 1-h infusion in patients with moderate renal impairment. Pharmacokinetic and microbiological data were obtained from the literature. The PTA and the cumulative fraction of response (CFR) were calculated by Monte Carlo simulation. In patients with normal renal function, the ceftaroline standard dose (600 mg q12 h as a 1-h infusion) can be sufficient to treat CABP due to ceftazidime-susceptible (CAZ-S) Escherichia coli, CAZ-S Klebsiella pneumoniae, meticillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis (CFR>90%). However, against meticillin-resistant S. aureus (MRSA), the CFR was 72%. In cSSSI, the CFR was also <80% for MRSA. Administration of ceftaroline 600 mg q8 h as a 2-h infusion or 400 mg q12 h as a 1-h infusion in patients with moderate renal insufficiency provided a high probability of treatment success (CFR ca. 100%) for most micro-organisms causing CABP and cSSSI, including MRSA and penicillin-non-susceptible S. pneumoniae. These results suggest that in patients with normal renal function, ceftaroline 600 mg q8 h as a 2-h infusion may be a better option than the standard dose, especially if the MRSA rate is high.

Development of novel antibacterial drugs to combat multiple resistant organisms

BACKGROUND

Infections due to multidrug-resistant (MDR) bacteria are increasing both in hospitals and in the community and are characterized by high mortality rates. New molecules are in development to face the need of active compounds toward resistant gram-positive and gram-negative pathogens. In particular, the Infectious Diseases Society of America (IDSA) has supported the initiative to develop ten new antibacterials within 2020. Principal targets are the so-called ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacteriaceae).

PURPOSE

To review the characteristics and the status of development of new antimicrobials including new cephalosporins, carbapenems, beta-lactamase inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines.

CONCLUSIONS

While numerous new compounds target resistant gram-positive pathogens and have been approved for clinical use, very few new molecules are active against MDR gram-negative pathogens, especially carbapenemase producers. New glycopeptides and oxazolidinones are highly efficient against methicillin-resistant S. aureus (MRSA), and new cephalosporins and carbapenems also display activity toward MDR gram-positive bacteria. Although new cephalosporins and carbapenems have acquired activity against MRSA, they offer few advantages against difficult-to-treat gram-negatives. Among agents that are potentially active against MDR gram-negatives are ceftozolane/tazobactam, new carbapenems, the combination of avibactam with ceftazidime, and plazomicin. Since a relevant number of promising antibiotics is currently in development, regulatory approvals over the next 5 years are crucial to face the growing threat of multidrug resistance.

What is the rate of methicillin-resistant Staphylococcus aureus and Gram-negative infections in open fractures?

BACKGROUND

There have been increasing reports of methicillin-resistant Staphylococcus aureus (MRSA) infections in the community, but it is unclear whether infectious organisms in open fracture infections have changed and if our current regimen of antibiotic prophylaxis is therefore obsolete.

QUESTIONS/PURPOSES

We determined the recent incidence of MRSA and Gram-negative organism infections after open fractures.

METHODS

We performed a retrospective cohort study on 189 patients with 202 open fractures treated from 2009 to 2010. During the followup, patients were evaluated for signs of infection using the Centers for Disease Control and Prevention criteria. We determined the organisms using routine microbiology culture. The minimum followup was 3 months (median, 47 months; range, 3-108 months).

RESULTS

Of the 202 open fractures, 20 (10%) developed infections. The most common organism was Staphylococcus, whereas five (25%) of those infected were positive for MRSA, and 11 (55%) of those with infection were cultured for at least one Gram-negative organism. Six (30%) open fractures had infections that grew out multiple organisms. The incidence of MRSA infections in our open fracture population was 2.5%.

CONCLUSIONS

There is a high incidence of MRSA and Gram-negative infections after open fractures, which may indicate that current antibiotic regimens need to be changed.

LEVEL OF EVIDENCE

Level IV, retrospective case-series. See the Guidelines for Authors for a complete description of levels of evidence.

New antibiotics for bad bugs: where are we?

Bacterial resistance to antibiotics is growing up day by day in both community and hospital setting, with a significant impact on the mortality and morbidity rates and the financial burden that is associated. In the last two decades multi drug resistant microorganisms (both hospital- and community-acquired) challenged the scientific groups into developing new antimicrobial compounds that can provide safety in use according to the new regulation, good efficacy patterns, and low resistance profile. In this review we made an evaluation of present data regarding the new classes and the new molecules from already existing classes of antibiotics and the ongoing trends in antimicrobial development. Infectious Diseases Society of America (IDSA) supported a proGram, called “the ′10 × ´20′ initiative”, to develop ten new systemic antibacterial drugs within 2020. The microorganisms mainly involved in the resistance process, so called the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and enterobacteriaceae) were the main targets. In the era of antimicrobial resistance the new antimicrobial agents like fifth generation cephalosporins, carbapenems, monobactams, β-lactamases inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines active against Gram-positive pathogens, like vancomycin-resistant S. aureus (VRSA) and MRSA, penicillin-resistant streptococci, and vancomycin resistant Enterococcus (VRE) but also against highly resistant Gram-negative organisms are more than welcome. Of these compounds some are already approved by official agencies, some are still in study, but the need of new antibiotics still does not cover the increasing prevalence of antibiotic-resistant bacterial infections. Therefore the management of antimicrobial resistance should also include fostering coordinated actions by all stakeholders, creating policy guidance, support for surveillance and technical assistance.

Ceftaroline fosamil: a review of its use in the treatment of complicated skin and soft tissue infections and community-acquired pneumonia

Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil (Zinforo, Teflaro), is an advanced-generation, parenteral cephalosporin with broad-spectrum antibacterial activity in vitro against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant Streptococcus pneumoniae and Gram-negative bacteria, including Haemophilus influenzae and Moraxella catarrhalis, but not Pseudomonas aeruginosa. Ceftaroline has demonstrated a low potential for the selection of resistance in vitro for drug-resistant Gram-positive organisms, including MRSA, as well as for Gram-negative respiratory pathogens. In pivotal phase III studies, intravenous ceftaroline fosamil demonstrated noninferiority to intravenous vancomycin plus aztreonam in patients hospitalized with complicated skin and soft tissue infections (cSSTIs) and intravenous ceftriaxone in patients hospitalized with community-acquired pneumonia (CAP) [Pneumonia Outcomes Research Team (PORT) risk class III or IV]; however, patients with CAP admitted to the intensive care unit were not evaluated. Ceftaroline fosamil was generally well tolerated in these trials, with an adverse event profile similar to that of other cephalosporins. Diarrhoea was the most commonly reported adverse event; however, the risk of Clostridium difficile-associated diarrhoea with ceftaroline fosamil appeared to be low. Potential limitations of the drug include the lack of an oral formulation and the requirement for twice-daily administration. Nonetheless, ceftaroline fosamil represents an attractive option (either alone or in combination with other agents) for the initial empirical treatment of patients hospitalized with cSSTIs (including those with suspected MRSA infection) or CAP (PORT risk class III or IV) who require intravenous antimicrobial therapy. As with all antibacterial agents, ceftaroline fosamil should be used in accordance with good antimicrobial stewardship.

Organic anion transporter 3 interacts selectively with lipophilic β-lactam antibiotics

Transporters are major determinants of the disposition of xenobiotics and endogenous chemicals in the body. Organic anion transporter 3 (Oat3) functions in the kidney and brain to remove metabolic waste, toxins, and drugs, and thus transports diverse chemicals. Some β-lactam antibiotics interact with Oat3, and penicillin G exhibits a strong dependence on Oat3 for renal elimination. However, over 80 β-lactams exist, and many have not been assessed for an interaction with Oat3. Moreover, β-lactams continue to receive U.S. Food and Drug Administration approval. This study identified new β-lactam-Oat3 interactions, provided a head-to-head comparison with Oat1, and characterized the physicochemical determinants of affinity for Oat3. Cells expressing mouse Oat3 (mOat3) and Oat1 (mOat1), and human OAT3 (hOAT3) were used to test inhibitors, and high-performance liquid chromatography (HPLC) was used to measure transport. Of 26 β-lactams tested, 12 were clear inhibitors of Oat3, and 14 exhibited poor interactions. Inhibitors exhibited a nearly identical rank-order of potency against mOat3 and hOAT3. Oat1 demonstrated a poor interaction with most β-lactams. The majority of Oat3 inhibitors were substrates, and there were clear physicochemical differences between inhibitors and noninhibitors. That is, inhibitors had nearly 40% fewer hydrogen bond donors (P < 0.001), a lower total polar surface area (P < 0.05), and greater lipophilicity (LogP of inhibitors, +1.41; noninhibitors, -1.54; P < 0.001). Pharmacophore mapping revealed a prohibitive hydrogen bond donor group in noninhibitors adjacent to a hydrophobic moiety that was important for binding to Oat3. These findings indicate that Oat3 recognizes lipophilic β-lactams more readily. Moreover, this study has potential implications for designing β-lactams to avoid renal accumulation or brain efflux via Oat3.

New antibiotic agents in the pipeline and how they can help overcome microbial resistance

Bacterial resistance is a growing threat and yet few new antibiotics active against multi-resistant bacteria are being explored. A combination of falling profits, regulatory mechanisms and irrational and injudicious use of antibiotics has led to an alarming situation where some infections have no cure. In this article, we summarize the new developments that have been suggested to incentivize the pharmaceutical industries toward the field of infections. We also briefly mention the new compounds on the horizon and some newly approved compounds that might help us tide over this crisis.