"Temocillin"

Impact of the phenotypic expression of temocillin resistance in Escherichia coli on temocillin efficacy in a murine peritonitis model. Temocillin is a narrow spectrum β-lactam active against MDR Enterobacterales. Mechanisms of acquired resistance to temocillin are poorly understood. We analysed resistance mechanisms in clinical isolates of Escherichia coli and evaluated their impact on temocillin efficacy in vitro and in a murine peritonitis model. Two sets of isogenic clinical E. coli strains were studied: a susceptible isolate (MLTEM16S) and its resistant derivative, MLTEM16R (mutation in nmpC porin gene); and temocillin-resistant derivatives of E. coli CFT073: CFT-ΔnmpC (nmpC deletion), CFTbaeS-TP and CFTbaeS-AP (two different mutations in the baeS efflux-pump gene).Fitness cost, time

Role of amino acid 159 in carbapenem and temocillin hydrolysis of OXA-933, a novel OXA-48 variant. OXA-48 has rapidly disseminated worldwide and become one of the most common carbapenemases in many countries with more than 45 variants reported with, in some cases, significant differences in their hydrolysis profiles. The R214 residue, located in the ß5-ß6 loop, is crucial for the carbapenemase

Temocillin for febrile urinary tract infections caused by ESBL-producing Enterobacteriaceae in children: a monocentric exposed/non-exposed study. To compare the efficacy of temocillin with standard of care (SOC) for treatment of ESBL-producing Enterobacteriaceae (ESBL-E) febrile urinary tract infection (ESBL-E FUTI) in children. A monocentric retrospective study of children hospitalized with confirmed ESBL-E FUTI from January 2015 to May 2022 was conducted, comparing clinical cure and a 3 month relapse between two groups of patients: 'exposed' patients (EP) and 'non-exposed' patients (NEP) to temocillin. EP received temocillin for at least 3 days. They were matched (1:1 ratio) on age group, sex and presence of uropathy with NEP who received SOC antibiotic therapy. Thirty-six temocillin

Implications of two-component systems EnvZ/OmpR and BaeS/BaeR in in vitro temocillin resistance in Escherichia coli. BaeS/BaeR is a two-component system of Escherichia coli that controls the expression of porins and efflux pumps. Its role in beta-lactam resistance is limited. To study the role of baeS/baeR two-component system in temocillin resistance in E. coli. E. coli strain BW25113 and single-gene deletion mutants related to two-component systems were collected from the KEIO collection. Double-gen deletion mutants were generated. Temocillin-resistant mutant frequencies were determined at 32 mg/L. E. coli BW25113 mutants were selected by selective pressure from serial passages. Biological costs were analysed by growth curves. Genomes of the generated mutants were sequenced

Pharmacokinetic/pharmacodynamic model-based optimization of temocillin dosing strategies for the treatment of systemic infections. Temocillin is increasingly considered as an alternative to carbapenems. However, there is no consensus on optimal dosing strategies and limited data on temocillin efficacy in systemic infections. We compared temocillin dosing strategies using pharmacokinetic /pharmacodynamic (PK/PD) modelling and simulation based on plasma exposure and in vitro time-kill data. Temocillin effects on four Escherichia coli strains were evaluated using static time-kill experiments and the hollow-fibre infection model, in which unbound plasma concentrations following intermittent and continuous infusion regimens of 4 and 6 g daily were replicated over 72 h. A PK/PD model was developed

Pharmacokinetics and pharmacological target attainment of standard temocillin dosing in non-critically ill patients with complicated urinary tract infections. Temocillin, a carbapenem-sparing β-lactam antibiotic, is commonly used at the standard 4 g/day dosage for treating complicated urinary tract infections (cUTIs). However, pharmacokinetic/pharmacodynamic (PK/PD) data supporting this regimen is limited. This study evaluated the plasma pharmacokinetics (PK) and PTA of temocillin in non-critically ill cUTI patients with varying degrees of renal insufficiency (RI). In this single-centre clinical study, 22 cUTI patients received a fixed 4 g/day (2 g q12h, intravenously) temocillin dose, irrespective of renal function (no RI: n = 5, mild RI: n = 8, moderate RI: n = 9). Plasma samples were collected

Evaluation of temocillin efficacy against KPC-2-producing Klebsiella pneumoniae isolates in a hollow-fibre infection model. Temocillin is an old antimicrobial that is resistant to hydrolysis by ESBLs but has variable activity against carbapenemase-producing Enterobacteriaceae. The current EUCAST susceptibility breakpoints for Enterobacterales are set at ≤16 mg/L (susceptible with increased exposure) based on a dose of 2 g q8h, but there is limited information on the efficacy of this dose against temocillin-susceptible carbapenemase-producing Klebsiella pneumoniae isolates. To evaluate the efficacy of this dose using a hollow-fibre infection model (HFIM) against six KPC-2-producing clinical isolates of K. pneumoniae. The isolates were characterized by WGS and temocillin susceptibility

Population pharmacokinetics and dosing simulations of temocillin in liver transplanted paediatric patients: a prospective, open-label, non-randomized study. Temocillin is a β-lactam antibiotic used for preventing or treating bacterial infections in liver-transplanted children. We characterized its pharmacokinetics in plasma and ascitic fluid and proposed dosing regimens that maximize achievement of effective drug exposures in this patient group. Patients aged 6-36 months received 25 mg/kg/12h (n=14) or 25 mg/kg/8h (n=23). Total and unbound temocillin concentrations were measured in plasma and ascitic fluid. Drug safety was monitored. Non-compartmental and population pharmacokinetic analyses were performed, together with Monte-Carlo simulations. No safety concerns were reported. For 25 mg/kg/12h

Temocillin efficacy against AmpC β-lactamase-producing Enterobacterales: a relevant alternative to cefepime? Temocillin is a semi-synthetic β-lactam with a narrow spectrum but high stability against hydrolysis by β-lactamases, including AmpC. Despite its favourable properties, data regarding its clinical value in the treatment of AmpC β-lactamase-producing Enterobacterales (ABPE) infections are scarce. Most recent guidelines do not include temocillin in the therapeutic strategy for ABPE infection. This study investigated (i) the proportion of ABPE isolates susceptible to temocillin and (ii) the clinical outcomes of patients treated with temocillin for ABPE infections. This retrospective multicentre (Bordeaux and Reunion Island) study was performed in two parts. First, all the antimicrobial

Stability of temocillin in outpatient parenteral antimicrobial therapy: is it a real option? Temocillin is an interesting alternative to carbapenems for susceptible Enterobacteriaceae. Although its use in outpatient parenteral antimicrobial therapy (OPAT) programmes has generated interest, this has been hampered by the lack of stability data. The purpose of the present study was to evaluate the physical and chemical stability of temocillin at the recommended dose for its use in OPAT programmes, contained in polypropylene infusion bags or polyisoprene elastomeric devices at different temperatures, and to describe a novel LC-MS/MS developed for the quantification of temocillin. Temocillin daily dose (6 g) was diluted in 500 mL of 0.9% sodium chloride to obtain a final concentration of 12 g/L

Population pharmacokinetics and dosing simulations of total and unbound temocillin in the plasma and CSF of neurocritically ill patients with external ventricular drain-related cerebral ventriculitis. Cerebral ventriculitis might be caused by Gram-negative bacteria, including ESBL producers. Temocillin may be a useful treatment option in this scenario; however, no consistent data are available regarding its penetration into the CSF. To describe the population pharmacokinetics of temocillin in plasma and CSF and to determine the probability for different simulated dosing regimens to achieve pharmacokinetic/pharmacodynamic (PK/PD) targets in the CSF. Ten post-neurosurgical critically ill adult patients requiring continuous drainage of CSF were included in this monocentric, prospective, open-label

Pharmacodynamics of Temocillin in Neutropenic Murine Infection Models. Temocillin is used for the treatment of various infections caused by . The pharmacokinetic (PK)/pharmacodynamic (PD) index that is best correlated with the activity of beta-lactams is the percentage of time that the unbound concentration exceeds the MIC (%T>MIC). However, the %T>MIC needed for a bacteriostatic or killing effect of temocillin is unknown in thigh and lung infection models. In the present study, we studied the temocillin PK in plasma and epithelial lining fluid (ELF) of infected neutropenic mice and determined the plasma exposure-response relationships for Escherichia coli and Klebsiella pneumoniae. Neutropenic murine thigh and lung infection models were used. The bacterial loads in the thighs or lungs

Usefulness of inclusion of ertapenem and temocillin screening breakpoints in the EUCAST rapid antimicrobial susceptibility testing (RAST) for rapid detection of OXA-48-producing Klebsiella pneumoniae directly from positive blood cultures. The aims of this study were: (i) to assess the ability of the meropenem screening breakpoint as part of the screening rapid antimicrobial susceptibility testing (sRAST) of EUCAST for the detection of OXA-48 carbapenemase-producing Klebsiella pneumoniae directly from positive blood cultures (BCs); and (ii) to evaluate the inclusion of ertapenem and temocillin discs into the sRAST to enhance the detection of OXA-48-producing isolates. BC bottles were spiked with a total of 117 K. pneumoniae isolates, including 77 previously characterized OXA-48 producers

Temocillin Resistance in the Enterobacter cloacae Complex Is Conferred by a Single Point Mutation in BaeS, Leading to Overexpression of the AcrD Efflux Pump. The Enterobacter cloacae complex (ECC) has become a major opportunistic pathogen with antimicrobial resistance issues. Temocillin, an "old" carboxypenicillin that is remarkably stable toward β-lactamases, has been used as an alternative for the treatment of multidrug-resistant ECC infections. Here, we aimed at deciphering the never-investigated mechanisms of temocillin resistance acquisition in . By comparative genomic analysis of two clonally related ECC clinical isolates, one susceptible (Temo_S [MIC of 4 mg/L]) and the other resistant (Temo_R [MIC of 32 mg/L]), we found that they differed by only 14 single-nucleotide polymorphisms, including

Binding of temocillin to plasma proteins in vitro and in vivo: the importance of plasma protein levels in different populations and of co-medications. Temocillin plasma protein binding (PPB) in healthy individuals is reported to be ∼85% but had not been studied in patients. To obtain normative data on temocillin PPB in patients in relation to infection and impact of co-medications widely used in ICU. Plasma was obtained from healthy individuals (Group #1), non-ICU patients with UTI (Group #2), ICU patients with suspected/confirmed ventriculitis (Group #3) or with sepsis/septic shock (Group #4). Total and unbound temocillin concentrations were measured in spiked samples from temocillin-naive donors (in vitro) or in plasma from temocillin-treated subjects (in vivo). The impact of diluting

Modelled Target Attainment after Temocillin Treatment in Severe Pneumonia: Systemic and Epithelial Lining Fluid Pharmacokinetics of Continuous versus Intermittent Infusions. The objective of this article is to describe the population pharmacokinetics (PK) of temocillin administered via continuous infusion (CI) versus intermittent infusion (II) in critically ill patients with pneumonia. Secondary objectives included characterization of epithelial lining fluid (ELF)/plasma penetration ratios and determination of the probability of target attainment (PTA) for a range of MICs. Thirty-two mechanically ventilated patients who were treated for pneumonia with 6 g of temocillin daily for sensitive pathogens were assigned to either the II (2 g every 8 h over 0.5 h) or the CI (6 g over 24 h after a loading

The clinical and microbiological efficacy of temocillin versus cefotaxime in adults with febrile urinary tract infection, and its effects on the intestinal microbiota: a randomised multicentre clinical trial in Sweden. Use of third-generation cephalosporins, such as cefotaxime, is associated with an increased risk of selection for antimicrobial resistance, so alternative antibiotics need to be considered. The aim of the present study was to evaluate intestinal colonisation with third-generation cephalosporin-resistant pathogens following use of temocillin-an alternative antibiotic to cefotaxime that is potentially less prone to disturbing the intestinal microbiota-in empirical treatment of febrile urinary tract infection (UTI). We did a randomised, multicentre, superiority, open-label phase 4

Temocillin versus carbapenems for urinary tract infection due to ESBL-producing Enterobacteriaceae: a multicenter matched case-control study. To compare the efficacy of temocillin with carbapenems for extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae urinary tract infections (ESBL-E UTI). A multicenter retrospective case-control study of adults with ESBL-E UTI was conducted between January 2015 and October 2019. Cases received temocillin ≥ 50% of the effective antibiotic therapy duration and controls exclusively received carbapenem; they were statistically matched (1:1 ratio) on 6-month period, sex and age. The clinical cure at the end of antibiotic therapy was analysed using conditional logistic regression. Seventy-two temocillin cases were matched to 72 carbapenem

Temocillin versus meropenem for the targeted treatment of bacteraemia due to third-generation cephalosporin-resistant Enterobacterales (ASTARTÉ): protocol for a randomised, pragmatic trial. Alternatives to carbapenems are needed in the treatment of third-generation cephalosporin-resistant (3GCR-E). Temocillin is a suitable candidate, but comparative randomised studies are lacking. The objective is to investigate if temocillin is non-inferior to carbapenems in the targeted treatment of bacteraemia due to 3GCR-E. Multicentre, open-label, randomised, controlled, pragmatic phase 3 trial. Patients with bacteraemia due to 3GCR-E will be randomised to receive intravenously temocillin (2 g three times a day) or carbapenem (meropenem 1 g three times a day or ertapenem 1 g once daily). The primary endpoint

Single-dose pharmacokinetics of temocillin in plasma and soft tissues of healthy volunteers after intravenous and subcutaneous administration: a randomized crossover microdialysis trial. The antibiotic temocillin has recently been rediscovered as a promising therapeutic option against MDR Gram-negative bacteria. However, some aspects of the pharmacokinetic (PK) profile of the drug are still to be elucidated: subcutaneous administration of temocillin might be of interest as an alternative to the intravenous route in selected patients. Similarly, information on the penetration of temocillin into human soft tissues is lacking. To investigate the feasibility and plasma PK of subcutaneous dosing as well as soft tissue PK of temocillin after intravenous administration to healthy volunteers. Eight healthy