Search

Objectives We evaluated the efficacies of human-simulated regimens (HSRs) of two clinically utilized sulbactam regimens: 1 g q6h 0.5 h infusion (maximum FDA-approved dosage) and 3 g q8h 4 h infusion (high-dose, prolonged-infusion regimen), against Acinetobacter baumannii in a translational murine model. Methods Thirty-two clinical A. baumannii isolates were investigated, of which 16 were sulbactam resistant (MIC ≥ 16 mg/L), 6 were sulbactam intermediate (MIC = 8 mg/L) and 10 were sulbactam susceptible (MIC ≤ 4 mg/L). Efficacies of the two sulbactam HSRs were assessed in the neutropenic murine pneumonia model. Changes in log10 cfu/lungs at 24 h compared with 0 h controls were measured, and efficacy was defined as achieving 1 log kill relative to baseline. WGS of the isolates and bioinformatics analysis were performed to explore potential associations between the genomic backgrounds and the in vivo responses. Results Eleven isolates harboured bla OXA-23, of which 10 were sulbactam resistant, 1 was sulbactam intermediate while none was sulbactam susceptible. Both sulbactam HSRs achieved >1 log kill against sulbactam-susceptible isolates. Against sulbactam-intermediate and sulbactam-resistant isolates, lack of efficacy correlated with the presence of the bla OXA-23 gene; sulbactam 1 g HSR and 3 g HSR did not show efficacy against 11/11 and 9/11 bla OXA-23-positive isolates, respectively, while efficacy was observed against all 11 bla OXA-23-negative sulbactam-intermediate and sulbactam-resistant isolates (i.e. harbouring other resistance genes). Conclusions A sulbactam high-dose prolonged-infusion regimen provides comparable activity to the standard dose against isolates currently considered sulbactam susceptible. However, the activity against isolates with intermediate and resistant susceptibility could be predicted by the detection of bla OXA-23. Enhancing detection capabilities of common diagnostic modalities to include OXA-23 can improve patient outcome. [ABSTRACT FROM AUTHOR]

Background Sulbactam dosing for Acinetobacter baumannii infections has not been standardized due to limited available pharmacokinetics/pharmacodynamics (PK/PD) data. Herein, we report a comprehensive PK/PD analysis of ampicillin-sulbactam against A. baumannii pneumonia. Methods Twenty-one A. baumannii clinical isolates were tested in the neutropenic murine pneumonia model. For dose-ranging studies, groups of mice were administered escalating doses of ampicillin-sulbactam. Changes in log10cfu/lungs relative to 0 h were assessed. Dose-fractionation studies were performed. Estimates of the percentage of of time during which the unbound plasma sulbactam concentrations exceeded the MIC (% f T > MIC) required for different efficacy endpoints were calculated. The probabilities of target attainment (PTA) for the 1-log kill plasma targets were estimated following clinically utilized sulbactam regimens. Results Dose-fractionation studies demonstrated time-dependent kill. Isolates resistant to both sulbactam and meropenem required three times the exposures to achieve 1-log kill; median [IQR] % f T > MIC of 60.37% [51.6–66.8] compared with other phenotypes (21.17 [16.0–32.9] % f T > MIC). Sulbactam standard dose (1 g q6h, 0.5 h infusion) provided >90% PTA up to MIC of 4 mg/L. Sulbactam 3 g q8h, 4 h inf provided greater PTA for isolates with sulbactam-intermediate susceptibility (8 mg/L, 100% versus 86% following the standard dose). Despite the higher exposure following 3 g q8h, 4 h inf, PTA was ≤57% among sulbactam-resistant/meropenem-resistant isolates. Conclusion Sulbactam standard dose is a valuable regimen across sulbactam-susceptible isolates while the high-dose extended-infusion provides additional benefit against sulbactam-intermediate isolates. Given that most of the sulbactam-resistant A. baumannii isolates are meropenem-resistant, high-dose prolonged-infusion regimens are not expected to be effective as monotherapy against infections due to these isolates. [ABSTRACT FROM AUTHOR]

Background: Infections caused by Klebsiella pneumoniae are common and result in high mortality rates. In vitro studies demonstrated the potency of cefoperazone/sulbactam (CPZ/SUL) against Klebsiella pneumoniae. However, the clinical efficacy of CPZ/SUL for the treatment of K. pneumoniae bacteremia has not been studied. Objectives: This study aimed to associate the clinical outcomes of patients with bacteremia with the minimal inhibitory concentrations (MICs) of CPZ/SUL against the causative K. pneumoniae isolates. Methods: This multicenter, retrospective study was conducted in Taiwan between July 2017 and April 2021. Patients with K. pneumoniae bacteremia treated with CPZ/SUL were enrolled in this study. CPZ/SUL MICs were determined using the agar dilution method. Data on the patients' clinical outcomes and characteristics were collected and analyzed. Results: In total, 201 patients were enrolled. Among the causative K. pneumoniae isolates, 180 (89.5%) were susceptible to CPZ/SUL. Most patients (n = 156, 77.6%) had favorable outcomes. The 30-day mortality rate was 11.9% (n = 24). Multivariate risk analyses showed that higher APACHE II score (Odds Ratio [OR], 1.14; Confidence Interval [CI], 1.07–1.21; p < 0.001), metastatic tumors (OR, 5.76; CI, 2.31–14.40; p < 0.001), and causative K. pneumoniae CPZ/SUL MICs > 16 µg/ml (OR, 4.30; CI, 1.50–12.27; p = 0.006) were independently associated with unfavorable outcomes. Conclusion: Patients with K. pneumoniae bacteremia treated with CPZ/SUL at a ratio 1:1 had favorable outcomes when the CPZ/SUL MICs were ≤ 16 µg/ml. Patients with higher APACHE II scores and metastatic tumors had unfavorable outcomes. [ABSTRACT FROM AUTHOR]

Purpose: Infections caused by Acinetobacter baumannii, particularly those resistant to antibiotics such as carbapenem, have become a global health crisis with a significant mortality rate. Hospital‐acquired pneumonia (HAP) and ventilator‐associated pneumonia (VAP) resulting from the A. baumannii‐calcoaceticus (ABC) complex represent a major clinical challenge. This review aimed to understand the approval process, mechanism of action, therapeutic potential, and future implications of sulbactam‐durlobactam therapy (SUL‐DUR). Methods: PubMed, Web of Science, EMBASE, Clinical trials. gov, ICTRP, and CENTRAL were searched for studies on SUL‐DUR for the treatment of hospital‐acquired pneumonia and ventilator‐associated pneumonia. Also, World Health Organization, U.S. Food and Drug Administration, and Centers for Disease Control and Prevention websites were searched for relevant information. Results: SUL‐DUR, marketed as Xacduro, is a novel pharmaceutical combination that functions as a narrow‐spectrum parenterally administered antibiotic. Sulbactam acts as a β‐lactamase inhibitor, whereas durlobactam protects against degradation by A. baumannii enzymes. A phase 1 trial successfully established the safety and tolerability of SUL‐DUR in patients with normal and mild renal impairment. A phase 2 trial demonstrated the safety and tolerability of SUL‐DUR in a larger population with urinary tract infections. A phase 3 trial showed that SUL‐DUR was non‐inferior to colistin in terms of mortality in A. baumannii‐related VAP, HAP, and bacteremia. Conclusion: The combination of sulbactam and durlobactam is a promising treatment option for HAP and VAP caused by ABC complex. [ABSTRACT FROM AUTHOR]

The addition of sulbactam restores the complete range of cefoperazone activity against bacteria and extends its spectrum of action to include the Acinetobacter species. The effectiveness of cefoperazone/sulbactam against multiresistant Acinetobacter baumannii has not been investigated. The purpose of the current meta-analysis was to compare the efficacy of cefoperazone/sulbactam-based therapeutic regimens and non-cefoperazone/sulbactam-based therapeutic regimens in the treatment of multiresistant Acinetobacter baumannii infections. The current meta-analysis of 10 retrospective studies provides evidence that cefoperazone/sulbactam-based therapeutic regimens are superior to non-cefoperazone/sulbactam-based therapeutic regimens in terms of 30-day mortality and clinical improvement in patients with multiresistant Acinetobacter baumannii infections. The risk of mortality was reduced by 38% among multiresistant Acinetobacter baumannii infections in patients who received cefoperazone/sulbactam-based therapeutic regimens. The cefoperazone/sulbactam-based combination therapy was superior to the cefoperazone/sulbactam monotherapy in terms of 30-day mortality when both therapeutic regimens were compared to the tigecycline monotherapy in patients with multiresistant Acinetobacter baumannii infections. [ABSTRACT FROM AUTHOR]

The US Food and Drug Administration recognizes the unmet medical need for antibacterial drugs to treat serious bacterial diseases caused by resistant pathogens for which effective therapies are limited or lacking. The agency also recognizes that designing and conducting clinical trials to assess the safety and efficacy of drugs to treat resistant infections is challenging, especially for drugs only active against a single or a few bacterial species, and that a more flexible development program might be appropriate. In this article, we discuss several regulatory considerations for flexible development programs for antibacterial drugs intended to meet an unmet medical need. As an example, we use the recent approval of sulbactam for injection and durlobactam for injection (XACDURO) for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia caused by susceptible isolates of Acinetobacter baumannii-calcoaceticus complex.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a Priority 1 (Critical) pathogen urgently requiring new antibiotics. Polymyxins are a last-line option against CRAB-associated infections. This transcriptomic study utilized a CRAB strain to investigate mechanisms of bacterial killing with polymyxin B, colistin, colistin B, and colistin/sulbactam combination therapy. After 4 h of 2 mg/L polymyxin monotherapy, all polymyxins exhibited common transcriptomic responses which primarily involved disruption to amino acid and fatty acid metabolism. Of the three monotherapies, polymyxin B induced the greatest number of differentially expressed genes (DEGs), including for genes involved with fatty acid metabolism. Gene disturbances with colistin and colistin B were highly similar (89 % common genes for colistin B), though effects on gene expression were generally lower (0–1.5-fold in most cases) with colistin B. Colistin alone (2 mg/L) or combined with sulbactam (64 mg/L) resulted in rapid membrane disruption as early as 1 h. Transcriptomic analysis of this combination revealed that the effects were driven by colistin, which included disturbances in fatty acid synthesis and catabolism, and inhibition of nutrient uptake. Combination therapy produced substantially higher fold changes in 72 % of DEGs shared with monotherapy, leading to substantially greater reductions in fatty acid biosynthesis and increases in biofilm, cell wall, and phospholipid synthesis. This indicates synergistic bacterial killing with the colistin/sulbactam combination results from a systematic increase in perturbation of many genes associated with bacterial metabolism. These mechanistic insights enhance our understanding of bacterial responses to polymyxin mono- and combination therapy and will assist to optimize polymyxin use in patients.

Treatment of neurosurgical intensive care patients infected with multidrug resistant (MDR) or extensive drug resistant (XDR) Acinetobacter baumannii presents significant challenges and is associated with high mortality rates. Sulbactam has long been an effective treatment for MDR Acinetobacter baumannii, particularly due to its ability to penetrate the inflamed blood -brain barrier, making it highly suitable for use in severe neurosurgical cases. However, in recent years, increasing resistance to sulbactam among Acinetobacter baumannii strains has become a concern. There is a lack of standardized guidelines regarding the dosage, administration methods, routes and combination therapy strategies for sulbactam in the treatment of these resistant infections. Thus, Chinese Neurosurgical Intensive Care Management Collaborative Group has developed the "Chinese expert consensus on the use of sulbactam to treat patients infected with Acinetobacter baumannii in the neurosurgical intensive care unit", through a thorough review of relevant evidence - based medical literature and extensive discussion and revision. This consensus includes 28 recommendations aimed at providing scientific and feasible clinical guidance for the application of sulbactam in the management of neurosurgical intensive care patients.

Objective: To review the pharmacology, efficacy, and safety of intravenous sulbactam-durlobactam (SUL-DUR) in the treatment of carbapenem-resistant Acinetobacter baumannii (CRAB) infections. Data Sources: PubMed databases and ClinicalTrials.gov were searched using the following terms: Sulbactam Durlobactam, ETX2514, Xacduro, Sulbactam-ETX2514, ETX2514SUL. Study Selection and Data Extraction: Articles published in English between January 1985 and September 13, 2023, related to pharmacology, safety, efficacy, and clinical trials were reviewed. Data Synthesis: A phase II trial compared SUL-DUR with placebo with imipenem and cilastatin in both groups. Overall treatment success in the microbiological intention-to-treat analysis was reported in 76.6% of patients in the SUL-DUR group compared with 81% patients in the placebo group. A phase III trial compared SUL-DUR with colistin in adults with confirmed CRAB infections. Patients received either SUL-DUR or colistin and background therapy with imipenem-cilastatin. SUL-DUR was noninferior to colistin for 28-day all-cause mortality (19% vs 32.3%, treatment difference −13.2%; 95% CI [−30.0 to 3.5]). Relevance to Patient Care and Clinical Practice in Comparison to Existing Drugs: Clinicians have limited options to treat CRAB infections. SUL-DUR has demonstrated efficacy against CRAB in patients with pneumonia and may be considered a viable treatment option. Nonetheless, potential impact of concomitant imipenem-cilastatin as background therapy on clinical trial findings is unclear. Further studies are needed to elucidate the role of SUL-DUR alone or in combination with other active antimicrobials for the treatment of CRAB infections. Conclusions: SUL-DUR has shown to be predominantly noninferior to alternative antibiotics in the treatment of pneumonias caused by CRAB, making it a viable treatment option. Further postmarketing data is needed to ascertain its role in other infections. [ABSTRACT FROM AUTHOR]

Treatment of neurosurgical intensive care patients infected with multidrug resistant (MDR) or extensive drug resistant (XDR) Acinetobacter baumannii presents significant challenges and is associated with high mortality rates. Sulbactam has long been an effective treatment for MDR Acinetobacter baumannii, particularly due to its ability to penetrate the inflamed blood -brain barrier, making it highly suitable for use in severe neurosurgical cases. However, in recent years, increasing resistance to sulbactam among Acinetobacter baumannii strains has become a concern. There is a lack of standardized guidelines regarding the dosage, administration methods, routes and combination therapy strategies for sulbactam in the treatment of these resistant infections. Thus, Chinese Neurosurgical Intensive Care Management Collaborative Group has developed the "Chinese expert consensus on the use of sulbactam to treat patients infected with Acinetobacter baumannii in the neurosurgical intensive care unit", through a thorough review of relevant evidence-based medical literature and extensive discussion and revision. This consensus includes 28 recommendations aimed at providing scientific and feasible clinical guidance for the application of sulbactam in the management of neurosurgical intensive care patients. [ABSTRACT FROM AUTHOR]

ABSTRACT Cefiderocol, a siderophore-cephalosporine conjugate antibiotic, shows promise as a therapeutic option for carbapenem-resistant (CR) Acinetobacter infections. While resistance has already been reported in A. baumannii, combination therapies with avibactam or sulbactam reduce MICs of cefiderocol, extending its efficacy. However, careful consideration is necessary when using these combinations. In our experiments, exposure of A. baumannii and A. lwoffii to cefiderocol and sulbactam or avibactam led to the selection of cefiderocol-resistant strains. Three of those were subjected to whole genome sequencing and transcriptomic analysis. The strains all possessed synonymous and non-synonymous substitutions and short deletions. The most significant mutations affected efflux pumps, transcriptional regulators, and iron homeostasis genes. Transcriptomics showed significant alterations in expression levels of outer membrane proteins, iron homeostasis, and β-lactamases, suggesting adaptive responses to selective pressure. This study underscores the importance of carefully assessing drug synergies, as they may inadvertently foster the selection of resistant variants and complicate the management of CR Acinetobacter infections.IMPORTANCEThe emergence of carbapenem-resistant Acinetobacter strains as a serious global health threat underscores the urgent need for effective treatment options. Although few drugs show promise against CR Acinetobacter infections, resistance to both drugs has been reported. In this study, the molecular characterization of spontaneous cefiderocol-resistant variants, a CR A. baumannii strain with antagonism to sulbactam, and an A. lwoffii strain with antagonism to avibactam, provides valuable insights into the mechanisms of resistance to cefiderocol. Some mechanisms observed are associated with mutations affecting efflux pumps, regulators, and iron homeostasis genes. These findings highlight the importance of understanding resistance mechanisms to optimize treatment options. They also emphasize the importance of early evaluation of drug synergies to address the challenges of antimicrobial resistance in Acinetobacter infections.

Abstract Purpose Infections caused by Acinetobacter baumannii, particularly those resistant to antibiotics such as carbapenem, have become a global health crisis with a significant mortality rate. Hospital‐acquired pneumonia (HAP) and ventilator‐associated pneumonia (VAP) resulting from the A. baumannii‐calcoaceticus (ABC) complex represent a major clinical challenge. This review aimed to understand the approval process, mechanism of action, therapeutic potential, and future implications of sulbactam‐durlobactam therapy (SUL‐DUR). Methods PubMed, Web of Science, EMBASE, Clinical trials. gov, ICTRP, and CENTRAL were searched for studies on SUL‐DUR for the treatment of hospital‐acquired pneumonia and ventilator‐associated pneumonia. Also, World Health Organization, U.S. Food and Drug Administration, and Centers for Disease Control and Prevention websites were searched for relevant information. Results SUL‐DUR, marketed as Xacduro, is a novel pharmaceutical combination that functions as a narrow‐spectrum parenterally administered antibiotic. Sulbactam acts as a β‐lactamase inhibitor, whereas durlobactam protects against degradation by A. baumannii enzymes. A phase 1 trial successfully established the safety and tolerability of SUL‐DUR in patients with normal and mild renal impairment. A phase 2 trial demonstrated the safety and tolerability of SUL‐DUR in a larger population with urinary tract infections. A phase 3 trial showed that SUL‐DUR was non‐inferior to colistin in terms of mortality in A. baumannii‐related VAP, HAP, and bacteremia. Conclusion The combination of sulbactam and durlobactam is a promising treatment option for HAP and VAP caused by ABC complex.

Amoxicillin and sulbactam are widely used in animal food compounding. Amoxicillin–sulbactam hybrid molecules are bicester compounds made by linking amoxicillin and sulbactam with methylene groups and have good application prospects. However, the residual elimination pattern of these hybrid molecules in animals needs to be explored. In the present study, the amoxicillin–sulbactam hybrid molecule (AS group) and a mixture of amoxicillin and sulbactam (mixture group) were administered to rats by gavage, and the levels of the major metabolites of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and sulbactam were determined by UPLC–MS/MS. The residue elimination patterns of the major metabolites in the liver, kidney, urine, and feces of rats in the AS group and the mixture group were compared. The results showed that the total amount of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and the highest concentration of sulbactam in the liver and kidney samples of the AS group and the mixture group appeared at 1 h after drug withdrawal. Between 1 h and 12 h post discontinuation, the total amount of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine in the two tissues decreased rapidly, and the elimination half-life of the AS group was significantly higher than that in the mixture group (p < 0.05); the residual amount of sulbactam also decreased rapidly, and the elimination half-life was not significantly different (p > 0.05). In 72 h urine samples, the total excretion rates were 60.61 ± 2.13% and 62.62 ± 1.73% in the AS group and mixture group, respectively. The total excretion rates of fecal samples (at 72 h) for the AS group and mixture group were 9.54 ± 0.26% and 10.60 ± 0.24%, respectively. These results showed that the total quantity of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine was eliminated more slowly in the liver and kidney of the AS group than those of the mixture group and that the excretion rate through urine and feces was essentially the same for both groups. The residual elimination pattern of the hybrid molecule in rats determined in this study provides a theoretical basis for the in-depth development and application of hybrid molecules, as well as guidelines for the development of similar drugs. [ABSTRACT FROM AUTHOR]

This review explores the evolution of the concept of Healthcare-Associated Pneumonia (HCAP) in light of the 2016 guidelines from the Infectious Diseases Society of America (IDSA). These updated guidelines prioritize patient-specific risk factors over healthcare system interactions in pneumonia classification. Recent research has revealed that the risk of contracting Multidrug-Resistant (MDR) pathogens is more closely linked to individual patient risk factors than to healthcare system interactions. Consequently, administering empiric antibiotic therapy targeting MDR bacteria for patients meeting HCAP criteria is discouraged unless specific risk factors for MDR infections are identifiable. Hospital-Acquired Pneumonia (HAP) is a significant challenge, particularly in intensive care units, leading to elevated hospitalization costs and extended inpatient care. The review also delves into the emergence and global prevalence of Carbapenem-Resistant Acinetobacter baumannii (CRAB) infections, known for their high mortality rates. In response to the rising threat of CRAB infections, the review introduces Sulbactam-Durlobactam (SUL-DUR) as a promising therapeutic solution. It examines the unique characteristics of Sulbactam and Durlobactam, both individually and in combination, and their potential in treating CRAB infections. Clinical trial data is presented to demonstrate the effectiveness and safety of SUL-DUR in addressing Hospital-Acquired Bacterial Pneumonia (HABP), Ventilator-Associated Bacterial Pneumonia (VABP), and bacteremia caused by the Acinetobacter baumannii-Calcoaceticus complex. The review also covers FDA-approved prescribing guidelines, dosage recommendations, adverse reactions, drug interactions, and usage in specific populations, including pregnant and lactating individuals. The management of renal and hepatic impairment and underscores the importance of monitoring for potential overdosage. While initial clinical evidence is promising, further research is essential to establish the full efficacy and safety profile of SUL-DUR. [ABSTRACT FROM AUTHOR]

Objectives An Escherichia coli isolate, WGS1363, showed resistance to piperacillin/tazobactam but susceptibility to cephalosporins and contained a previously unrecognized β-lactamase, CTX-M-255, as the only acquired β-lactamase. CTX-M-255 was identical to CTX-M-27 except for a G239S substitution. Here, we characterize the hydrolytic spectrum of CTX-M-255 and a previously reported β-lactamase, CTX-M-178, also containing a G239S substitution and compare it to their respective parental enzymes, CTX-M-27 and CTX-M-15. Methods All β-lactamase genes were expressed in E. coli TOP10 and MICs to representative β-lactam-antibiotics were determined. Furthermore, bla CTX-M-15,   bla CTX-M-27, bla CTX-M-178 and bla CTX-M-255 with C-terminal His-tag fusions were affinity purified for enzyme kinetic assays determining Michaelis–Menten kinetic parameters against representative β-lactam-antibiotics and IC50s of clavulanate, sulbactam, tazobactam and avibactam. Results TOP10-transformants expressing bla CTX-M-178 and bla CTX-M-255 showed resistance to penicillin/β-lactamase combinations and susceptibility to cephalothin and cefotaxime in contrast to transformants expressing bla CTX-M-15 and bla CTX-M-27. Determination of enzyme kinetic parameters showed that CTX-M-178 and CTX-M-255 both lacked hydrolytic activity against cephalosporins and showed impaired hydrolytic efficiency against penicillin antibiotics compared to their parental enzymes. Both enzymes appeared more active against piperacillin compared to benzylpenicillin and ampicillin. Compared to their parental enzymes, IC50s of β-lactamase-inhibitors were increased more than 1000-fold for CTX-M-178 and CTX-M-255. Conclusions CTX-M-178 and CTX-M-255, both containing a G239S substitution, conferred resistance to piperacillin/tazobactam and may be characterized as inhibitor-resistant CTX-M β-lactamases. Inhibitor resistance was accompanied by loss of activity against cephalosporins and monobactams. These findings add to the necessary knowledge base for predicting antibiotic susceptibility from genotypic data. [ABSTRACT FROM AUTHOR]

Objective We aimed to assess the efficacy of cefoperazone/sulbactam (CPZ/SUL) in extended-spectrum β-lactamase (ESBL)-producing Enterobacterales infections and identify factors influencing outcomes. Methods This retrospective multicentre study was conducted in Taiwan (January 2015 to December 2020) and examined the efficacy of CPZ/SUL treatment in ESBL-producing Enterobacterales bacteraemia. The minimum inhibitory concentrations (MICs) were determined using agar dilution; ESBL/AmpC genes were detected using polymerase chain reaction. The primary outcome was clinical success, whereas the secondary outcome was 30-day mortality. Clinical success was defined as the complete resolution of clinical signs and symptoms of K. pneumoniae or E. coli infection, with no evidence of persistent or recurrent bacteraemia. The factors influencing outcomes were identified using a multivariate analysis. Results CPZ/SUL demonstrated a clinical success rate of 82.7% (91/110) in treating ESBL-producing Enterobacterales bacteraemia, with a 30-day mortality rate of 9.1% (10/110). Among 110 ESBL-producing isolates, a high clinical success rate was observed at an MIC of ≤32/32 mg/L. Multivariate analysis revealed that a Charlson comorbidity index (CCI) of ≥6 was associated with lower clinical success [odds ratio (OR): 5.80, 95% confidence interval (CI): 1.15–29.14, P = 0.033]. High Sequential Organ Failure Assessment scores (≥6) were significantly associated with increased 30-day mortality (OR: 14.34, 95% CI: 1.45–141.82, P = 0.023). Discussion CPZ/SUL demonstrated a clinical success rate of 82.7% (91/110) in treating ESBL-producing Enterobacterales bacteraemia. Treatment success was evident when the CPZ and SUL MIC was ≤32/32 mg/L. Comorbidities (CCI ≥6) were associated with lower clinical success, while disease severity (Sequential Organ Failure Assessment score ≥6) correlated with higher mortality. [ABSTRACT FROM AUTHOR]

The treatment of Acinetobacter baumannii infections remains a challenge for physicians worldwide in the 21st century. The bacterium possesses a multitude of mechanisms to escape the human immune system. The consequences of A. baumannii infections on morbidity and mortality, as well on financial resources, remain dire. Furthermore, A. baumannii superinfections have also occurred during the COVID-19 pandemic. While prevention is important, the antibiotic armamentarium remains the most essential factor for the treatment of these infections. The main problem is the notorious resistance profile (including resistance to carbapenems and colistin) that this bacterium exhibits. While newer beta lactam/beta-lactamase inhibitors have entered clinical practice, with excellent results against various infections due to Enterobacteriaceae, their contribution against A. baumannii infections is almost absent. Hence, we have to resort to at least one of the following, sulbactam, polymyxins E or B, tigecycline or aminoglycosides, against multidrug-resistant (MDR) and extensively drug-resistant (XDR) A. baumannii infections. Furthermore, the notable addition of cefiderocol in the fight against A. baumannii infections represents a useful addition. We present herein the existing information from the last decade regarding therapeutic advances against MDR/XDR A. baumannii infections. [ABSTRACT FROM AUTHOR]

Background: Piperacillin/tazobactam has limited activity against Enterobacterales, which concurrently express ESBL/ampC/OXA-1 beta-lactamases, which are widely prevalent in India. Thus, there is a severe dearth for carbapenem sparing options that aggravate more dependent carbapenem therapy. In the Indian market, various cefepime/BLI combinations in diiferent fixed ratios were introduced to clinical practice. We investigated the activity of cefepime with increased sulbactam ratios against contemporary isolates of ESBL/OXA-1 expressing Enterobacterales. Methods: Non-duplicate contemporary ESBL and/or OXA-1 expressing E. coli (n = 117) and K. pneumoniae (n = 71) isolates were included in this study. The MIC of cefepime/sulbactam and its comparators were determined using a broth microdilution method. The presence of ESBL and OXA-1 genes were identified using multiplex PCR. Results: Against ESBL and OXA-1 co-producing E. coli, cefepime combined with sulbactam at 8 mg/L, inhibited 82% of the isolates. Cefoperazone susceptibility against ESBL-E. coli increased from 52% at 4 mg/L to 77% at 8 mg/L with sulbactam. When tested against K. pneumoniae co-expressing ESBL and OXA-1, cefepime susceptibility was 77% at 4 mg/L sulbactam and 88% at 8 mg/L sulbactam. PTZ consistently showed limited activity against ESBL co-harbouring OXA-1 (E. coli, 43% and K. pneumoniae, 61%). Conclusion: The present study demonstrates that adding an increased sulbactam concentration enhances cefepime's activity against contemporary ESBL/OXA-1 expressing Enterobacterales. A reformulated cefepime/sulbactam (2 g/2 g) combination may be the best carbapenem sparing option until cefepime/tazobactam and cefepime/enmetazobactam become available in the future.

The addition of sulbactam restores the complete range of cefoperazone activity against bacteria and extends its spectrum of action to include the Acinetobacter species. The effectiveness of cefoperazone/sulbactam against multiresistant Acinetobacter baumannii has not been investigated. The purpose of the current meta-analysis was to compare the efficacy of cefoperazone/sulbactam-based therapeutic regimens and non-cefoperazone/sulbactam-based therapeutic regimens in the treatment of multiresistant Acinetobacter baumannii infections. The current meta-analysis of 10 retrospective studies provides evidence that cefoperazone/sulbactam-based therapeutic regimens are superior to non-cefoperazone/sulbactam-based therapeutic regimens in terms of 30-day mortality and clinical improvement in patients with multiresistant Acinetobacter baumannii infections. The risk of mortality was reduced by 38% among multiresistant Acinetobacter baumannii infections in patients who received cefoperazone/sulbactam-based therapeutic regimens. The cefoperazone/sulbactam-based combination therapy was superior to the cefoperazone/sulbactam monotherapy in terms of 30-day mortality when both therapeutic regimens were compared to the tigecycline monotherapy in patients with multiresistant Acinetobacter baumannii infections.

A new, simple hight performance thin layer chromatography (HPTLC)-Spectrodensitometric strategy was created and approved for the synchronous estimation of four antibacterial specialists: ceftazidime (CEF), tazobactam (TAZ), tobramycin (TOB) and sulbactam (SUL). The four compounds were separated on TLC aluminum plates covered with silica gel 60 F254, using chloroform–acetonitrile–methanol–ammonia (4:1:0.5:0.15, v/v/v/v) as a mobile phase at 254 nm. Linear correlation was obeyed over the concentration ranges of 12.0–72.0, 2.0–12.0, 3.0–18.0 and 10.0–50.0 μg mL−1 for CEF, TAZ, TOB and SUL, respectively. The proposed approach is efficient, repeatable and convenient as a flexible method for the quality control of diverse combinations of these pharmaceuticals in various pharmaceutical preparations, with high percent recoveries that are highly consistent with labeled data. When the findings of the proposed technique were compared to those of the comparison methods, there were no critical contrasts in terms of precision and accuracy. [ABSTRACT FROM AUTHOR]

Here, we illustrate what happens inside the catalytic cleft of an enzyme when substrate or ligand binds on single-millisecond timescales. The initial phase of the enzymatic cycle is observed with near-atomic resolution using the most advanced X-ray source currently available: the European XFEL (EuXFEL). The high repetition rate of the EuXFEL combined with our mix-and-inject technology enables the initial phase of ceftriaxone binding to the Mycobacterium tuberculosis β-lactamase to be followed using time-resolved crystallography in real time. It is shown how a diffusion coefficient in enzyme crystals can be derived directly from the X-ray data, enabling the determination of ligand and enzyme-ligand concentrations at any position in the crystal volume as a function of time. In addition, the structure of the irreversible inhibitor sulbactam bound to the enzyme at a 66 ms time delay after mixing is described. This demonstrates that the EuXFEL can be used as an important tool for biomedically relevant research.

Objective: Monotherapy with a beta lactam or a cephalosporin has become the standard of care for the treatment of febrile neutropenia (FEN). We aimed to evaluate the efficacy of cefoperazone/sulbactam (CS) as empirical monotherapy for febrile neutropenia in children with solid tumors and lymphomas. Material and Methods: Children with FEN received cefaperazone-sulbactam (80 mg/kg/day, every 8 hours). Treatment responses (a) successful, complete resolution of all signs and symptoms of infection at 72 hours and after 7 days of CS treatment; (b) success with modification, change of therapy for viral, parasitic or fungal infection or addition of glycopeptides; (c) failure was defined as the emergence of a new or resistant infection, treatment-resistant bacteremia, the need to switch to carbapenems. Results: Our study included 157 patients and 350 febrile neutropenia episodes. The most common diagnoses were osteosarcoma (35%), Ewing sarcoma (30%), non-hodgkin lymphoma (13%) and rhabdomyosarcoma (9%), respectively. The origin of fever could not be determined in 223 (64%) of FEN episodes, 79 (22%) had microbiologically documented infection (MDI), and 48 (14%) had clinically documented infection (CDI). The success rate was 65% (229), the success rate with modification was 9% (31) and the failure rate was 26% (90). SC monotherapy was successful in 33% of attacks with MDI and in 60% of attacks with CDI. However, SC monotherapy was successful in 82% of febrile episodes of unknown origin. Conclusion: Cefoperazone/sulbactam is effective and safe in febrile neutropenic children with solid tumors and lymphomas for monotherapy. [ABSTRACT FROM AUTHOR]

Objectives: Different platelet-rich fibrin (PRF) protocols exist and are known to differ in resulting mechanical and bioactive properties. Centrifugation parameters may also influence drug release, in particular antibiotics, when using PRF as a bio-carrier. We thus evaluated three common protocols regarding effects on the bio-carrier properties. Materials and methods: In a prospective trial comprising 33 patients, we compared different protocols for PRF as a bio-carrier for ampicillin/sulbactam (SAM). Blood samples were taken shortly after a single dose of ampicillin/sulbactam (2 g/1 g) was administered to patients intravenously. PRF was obtained by centrifugation and three protocols were used: protocol A (1300 rpm, 8 min, RCF-max = 208 g), B (2300 rpm, 12 min, RCF-max = 652 g), and C (1500 rpm, 14 min, RCF-max = 276 g). The antibacterial activity of PRF was investigated against five oral species in vitro, based on agar diffusion methodology. Results: The study demonstrates that a single dose of SAM is sufficient to reach high concentrations in PRF in all protocols (150 µg/ml), which is comparable to the plasma SAM concentration. Antibacterial activity was inferred from the diameter of inhibition zones seen in agar diffusion tests using PRF discs. Protocol B resulted in the largest inhibition zones. One-way ANOVA revealed statistically improved results for protocol B for some bacteria. Conclusions: The study provides valuable data on PRF antibiotic enrichment, notably SAM. A single dose of SAM is sufficient to reach clinically relevant concentrations in PRF. Clinical relevance: These findings potentially extend the application of PRF, for example in patients with osteonecrosis of the jaw or in oral surgery (e.g., stick bone). [ABSTRACT FROM AUTHOR]

Despite the presence of more than 100 different antibacterials in the therapeutic arsenal, beta-lactam antibiotics, in general, and the third-generation cephalosporins, in particular, remain the main option for the treatment of the most of infections in inpatients. At the same time, the widespread and oftentimes inappropriate use of the third-generation cephalosporins in Russian hospitals lead to the emergence and spread of antimicroabial resistance. The review covers the problems of antibiotic resistance to cephalosporins due to the production of beta-lactamases, the role of beta-lactamase inhibitors in overcoming this type of resistance, options for combinations of cephalosporins with beta-lactamase inhibitors, in vitro activity of cefotaxime/sulbactam and cefepime/sulbactam, the results of clinical studies, and the role of the above combinations in the treatment of infections in the hospital.

Amoxicillin and sulbactam are widely used in animal food compounding. Amoxicillin–sulbactam hybrid molecules are bicester compounds made by linking amoxicillin and sulbactam with methylene groups and have good application prospects. However, the residual elimination pattern of these hybrid molecules in animals needs to be explored. In the present study, the amoxicillin–sulbactam hybrid molecule (AS group) and a mixture of amoxicillin and sulbactam (mixture group) were administered to rats by gavage, and the levels of the major metabolites of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and sulbactam were determined by UPLC–MS/MS. The residue elimination patterns of the major metabolites in the liver, kidney, urine, and feces of rats in the AS group and the mixture group were compared. The results showed that the total amount of amoxicillin, amoxicilloic acid, amoxicillin diketopiperazine, and the highest concentration of sulbactam in the liver and kidney samples of the AS group and the mixture group appeared at 1 h after drug withdrawal. Between 1 h and 12 h post discontinuation, the total amount of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine in the two tissues decreased rapidly, and the elimination half-life of the AS group was significantly higher than that in the mixture group (p < 0.05); the residual amount of sulbactam also decreased rapidly, and the elimination half-life was not significantly different (p > 0.05). In 72 h urine samples, the total excretion rates were 60.61 ± 2.13% and 62.62 ± 1.73% in the AS group and mixture group, respectively. The total excretion rates of fecal samples (at 72 h) for the AS group and mixture group were 9.54 ± 0.26% and 10.60 ± 0.24%, respectively. These results showed that the total quantity of amoxicillin, amoxicilloic acid, and amoxicillin diketopiperazine was eliminated more slowly in the liver and kidney of the AS group than those of the mixture group and that the excretion rate through urine and feces was essentially the same for both groups. The residual elimination pattern of the hybrid molecule in rats determined in this study provides a theoretical basis for the in-depth development and application of hybrid molecules, as well as guidelines for the development of similar drugs.

The treatment of Acinetobacter baumannii infections remains a challenge for physicians worldwide in the 21st century. The bacterium possesses a multitude of mechanisms to escape the human immune system. The consequences of A. baumannii infections on morbidity and mortality, as well on financial resources, remain dire. Furthermore, A. baumannii superinfections have also occurred during the COVID-19 pandemic. While prevention is important, the antibiotic armamentarium remains the most essential factor for the treatment of these infections. The main problem is the notorious resistance profile (including resistance to carbapenems and colistin) that this bacterium exhibits. While newer beta lactam/beta-lactamase inhibitors have entered clinical practice, with excellent results against various infections due to Enterobacteriaceae, their contribution against A. baumannii infections is almost absent. Hence, we have to resort to at least one of the following, sulbactam, polymyxins E or B, tigecycline or aminoglycosides, against multidrug-resistant (MDR) and extensively drug-resistant (XDR) A. baumannii infections. Furthermore, the notable addition of cefiderocol in the fight against A. baumannii infections represents a useful addition. We present herein the existing information from the last decade regarding therapeutic advances against MDR/XDR A. baumannii infections.