scholarly journals In VivoPharmacodynamic Study of Cefiderocol, a Novel Parenteral Siderophore Cephalosporin, in Murine Thigh and Lung Infection Models

2019 ◽  
Vol 63 (9) ◽  
Author(s):  
Rio Nakamura ◽  
Tsukasa Ito-Horiyama ◽  
Miki Takemura ◽  
Shinsuke Toba ◽  
Shuhei Matsumoto ◽  
...  
Keyword(s):  
Lung Infection ◽  
Infection Model ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Mueller Hinton ◽  
Infection Models ◽  
Resistant Strains ◽  
The Mean ◽  
Mueller Hinton Broth

ABSTRACTThe pharmacokinetic (PK) and pharmacodynamic (PD) parameters which correlated with thein vivoefficacy of cefiderocol were evaluated using neutropenic murine thigh and lung infection models in which the infections were caused by a variety of Gram-negative bacilli. The dose fractionation study using the thigh infection model in which the infection was caused byPseudomonas aeruginosashowed that the cumulative percentage of a 24-h period that the free drug concentration in plasma exceeds the MIC (%fT>MIC) rather than the free peak level divided by the MIC (fCmax/MIC) and the area under the free concentration-time curve over 24 h divided by the MIC (fAUC/MIC) was the PK/PD parameter that best correlated with efficacy. The study with multiple carbapenem-resistant strains revealed that the %fT>MICdetermined in iron-depleted cation-adjusted Mueller-Hinton broth (ID-CAMHB) better reflected thein vivoefficacy of cefiderocol than the %fT>MICdetermined in cation-adjusted Mueller-Hinton broth (CAMHB). The mean %fT>MICof cefiderocol required for a 1-log10reduction against 10 strains ofEnterobacteriaceaeand 3 strains ofPseudomonas aeruginosain the thigh infection models were 73.3% and 77.2%, respectively. The mean %fT>MICforEnterobacteriaceae,P. aeruginosa,Acinetobacter baumannii, andStenotrophomonas maltophiliain the lung infection model were 64.4%, 70.3%, 88.1%, and 53.9%, respectively. These results indicate that cefiderocol has potent efficacy against Gram-negative bacilli, including carbapenem-resistant strains, irrespective of the bacterial species, in neutropenic thigh and lung infection models and that thein vivoefficacy correlated with thein vitroMIC under iron-deficient conditions.

scholarly journals Assessment of the In Vivo Efficacy of WCK 5222 (Cefepime-Zidebactam) against Carbapenem-Resistant Acinetobacter baumannii in the Neutropenic Murine Lung Infection Model

2018 ◽  
Vol 62 (11) ◽  
Author(s):  
Lindsay M. Avery ◽  
Kamilia Abdelraouf ◽  
David P. Nicolau
Keyword(s):  
Acinetobacter Baumannii ◽  
Lung Infection ◽  
Infection Model ◽  
Bacterial Burden ◽  
In Vivo Efficacy ◽  
Content Type ◽  
Murine Lung ◽  
Carbapenem Resistant ◽  
The Mean

ABSTRACT We evaluated the in vivo efficacy of human-simulated WCK 5222 (cefepime-zidebactam) against cefepime-resistant Acinetobacter baumannii strains (n = 13) in the neutropenic murine lung infection model. Twelve isolates were meropenem resistant. In control animals and those that received cefepime or zidebactam alone, the mean bacterial growth at 24 h was >2 log10 CFU/lung compared with 0-h controls (6.32 ± 0.33 log10 CFU/lung). WCK 5222 produced a decline in the bacterial burden for all isolates (mean reduction, −3.34 ± 0.85 log10 CFU/lung) and demonstrated remarkable potency.

scholarly journals Activity of Meropenem-Vaborbactam in Mouse Models of Infection Due to KPC-Producing Carbapenem-Resistant Enterobacteriaceae

2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Mojgan Sabet ◽  
Ziad Tarazi ◽  
Thomas Nolan ◽  
Jonathan Parkinson ◽  
Debora Rubio-Aparicio ◽  
...  
Keyword(s):  
Body Weight ◽  
Lung Infection ◽  
Infection Model ◽  
Bacterial Killing ◽  
Gram Negative ◽  
Content Type ◽  
Highly Active ◽  
Carbapenem Resistant ◽  
Infection Models ◽  
Carbapenem Resistant Enterobacteriaceae

ABSTRACT Meropenem-vaborbactam (Vabomere) is highly active against Gram-negative pathogens, especially Klebsiella pneumoniae carbapenemase (KPC)-producing, carbapenem-resistant Enterobacteriaceae. The objective of these studies was to evaluate the efficacy of meropenem alone and in combination with vaborbactam in mouse thigh and lung infection models. Thighs or lungs of neutropenic mice were infected with KPC-producing carbapenem-resistant Enterobacteriaceae, with meropenem MICs ranging from ≤0.06 to 8 mg/liter in the presence of 8 mg/liter vaborbactam. Mice were treated with meropenem alone or meropenem in combination with vaborbactam every 2 h for 24 h to provide exposures comparable to 2-g doses of each component in humans. Meropenem administered in combination with vaborbactam produced bacterial killing in all strains tested, while treatment with meropenem alone either produced less than 0.5 log CFU/tissue of bacterial killing or none at all. In the thigh model, 11 strains were treated with the combination of meropenem plus vaborbactam (300 plus 50 mg/kg of body weight). This combination produced from 0.8 to 2.89 logs of bacterial killing compared to untreated controls at the start of treatment. In the lung infection model, two strains were treated with the same dosage regimen of meropenem and vaborbactam. The combination produced more than 1.83 logs of bacterial killing against both strains tested compared to untreated controls at the start of treatment. Overall, these data suggest that meropenem-vaborbactam may have utility in the treatment of infections due to KPC-producing carbapenem-resistant Enterobacteriaceae.

scholarly journals In Vivo Efficacy of Novel Monobactam LYS228 in Murine Models of Carbapenemase-Producing Klebsiella pneumoniae Infection

2019 ◽  
Vol 63 (4) ◽  
Author(s):  
W. J. Weiss ◽  
M. E. Pulse ◽  
P. Nguyen ◽  
E. J. Growcott
Keyword(s):  
Klebsiella Pneumoniae ◽  
Clinical Development ◽  
Murine Models ◽  
Bacterial Burden ◽  
In Vivo Efficacy ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Infection Models ◽  
Resistant Strains

ABSTRACT LYS228 has potent antibacterial activity against carbapenem-resistant strains of Enterobacteriaceae. LYS228 was efficacious in neutropenic thigh models established with Klebsiella pneumoniae producing KPC-2 or NDM-1; pretreatment with uranyl nitrate considerably shifted calculated static doses of LYS228. In murine ascending pyelonephritis, LYS228 reduced bacterial burden in kidney, urine, and bladder. The successful treatment of murine infection models established with carbapenem-resistant K. pneumoniae further supports the clinical development of LYS228.

scholarly journals Pharmacokinetic-Pharmacodynamic Evaluation of Gepotidacin against Gram-Positive Organisms Using Data from Murine Infection Models

2016 ◽  
Vol 61 (2) ◽  
Author(s):  
Catharine C. Bulik ◽  
Ólanrewaju O. Okusanya ◽  
Elizabeth A. Lakota ◽  
Alan Forrest ◽  
Sujata M. Bhavnani ◽  
...  
Keyword(s):  
Lung Infection ◽  
Free Drug ◽  
Dose Fractionation ◽  
Infection Model ◽  
Time Curve ◽  
Content Type ◽  
Drug Plasma ◽  
Infection Models

ABSTRACT Gepotidacin (formerly called GSK2140944) is a novel triazaacenaphthylene bacterial topoisomerase inhibitor with in vitro activity against conventional and biothreat pathogens, including Staphylococcus aureus and Streptococcus pneumoniae. Using neutropenic murine thigh and lung infection models, the pharmacokinetics-pharmacodynamics (PK-PD) of gepotidacin against S. aureus and S. pneumoniae were characterized. Candidate models were fit to single-dose PK data from uninfected mice (for doses of 16 to 128 mg/kg of body weight given subcutaneously [s.c.]). Dose fractionation studies (1 isolate/organism; 2 to 512 mg/kg/day) and dose-ranging studies (5 isolates/organism; 2 to 2,048 mg/kg/day; MIC ranges of 0.5 to 2 mg/liter for S. aureus and 0.125 to 1 mg/liter for S. pneumoniae) were conducted. The presence of an in vivo postantibiotic effect (PAE) was also evaluated. Relationships between the change from baseline in log10 CFU at 24 h and the ratio of the free-drug plasma area under the concentration-time curve (AUC) to the MIC (AUC/MIC ratio), the ratio of the maximum concentration of drug in plasma (C max) to the MIC (C max/MIC ratio), and the percentage of a 24-h period that the drug concentration exceeded the MIC (%T>MIC) were evaluated using Hill-type models. Plasma and epithelial lining fluid (ELF) PK data were best fit by a four-compartment model with linear distributional clearances, a capacity-limited clearance, and a first-order absorption rate. The ELF penetration ratio in uninfected mice was 0.65. Since the growth of both organisms was poor in the murine lung infection model, lung efficacy data were not reported. As determined using the murine thigh infection model, the free-drug plasma AUC/MIC ratio was the PK-PD index most closely associated with efficacy (r 2 = 0.936 and 0.897 for S. aureus and S. pneumoniae, respectively). Median free-drug plasma AUC/MIC ratios of 13.4 and 58.9 for S. aureus, and 7.86 and 16.9 for S. pneumoniae, were associated with net bacterial stasis and a 1-log10 CFU reduction from baseline, respectively. Dose-independent PAE durations of 3.07 to 12.5 h and 5.25 to 8.46 h were demonstrated for S. aureus and S. pneumoniae, respectively.

scholarly journals Pharmacodynamics of a New Streptogramin, XRP 2868, in Murine Thigh and Lung Infection Models

2006 ◽  
Vol 50 (1) ◽  
pp. 243-249 ◽  
Author(s):  
D. Andes ◽  
W. A. Craig
Keyword(s):  
Time Course ◽  
Lung Infection ◽  
Infection Model ◽  
Pharmacokinetic Studies ◽  
Strain Atcc ◽  
Beta Lactam ◽  
Time Curve ◽  
Infection Models ◽  
Resistant Strains

ABSTRACT XRP 2868 is a new streptogramin antibiotic with broad-spectrum activity against gram-positive cocci. We used the neutropenic murine thigh and lung infection models to characterize the time course of antimicrobial activity of XRP 2868 and determine which pharmacokinetic/pharmacodynamic (PK/PD) parameter and magnitude best correlated with efficacy. Serum levels following four two- to fourfold-escalating single-dose levels of XRP 2868 were measured by liquid chromatography mass spectrometry assay. In vivo postantibiotic effects (PAEs) were determined after doses of 2.5, 10, and 40 mg/kg. Mice had 106.8 to 108.4 CFU/thigh of strains of Streptococcus pneumoniae ATCC 10813 or Staphylococcus aureus ATCC 29213 at the start of therapy when treated for 24 h with 2.5 to 640 mg/kg/day of XRP 2868 fractionated for 3-, 6-, 12-, and 24-h dosing regimens. Nonlinear regression analysis was used to determine which PK/PD parameter best correlated with CFU/thigh at 24 h. Pharmacokinetic studies exhibited peak dose values of 0.03 to 0.07, area under the concentration-time curve (AUC) dose values of 0.02 to 0.07, and half-lives of 0.35 to 1.27 h. XRP 2868 produced in vivo PAEs of 0.5 to 3.4 h with S. pneumoniae strain ATCC 10813 and −1.5 to 10.7 h with S. aureus strain ATCC 29213. The 24-h AUC/MIC was the PK/PD parameter that best correlated with efficacy. In subsequent studies, we used the neutropenic murine thigh infection model to determine if the magnitude of the AUC/MIC needed for the efficacy of XRP 2868 varied among pathogens (including resistant strains). Mice had 106.1 to 107.8 CFU/thigh of four isolates of S. aureus (three methicillin-susceptible and one methicillin-resistant strain) and nine isolates of S. pneumoniae (one penicillin-susceptible, four penicillin-intermediate, and four penicillin-resistant strains) when treated for 24 h with 0.16 to 640 mg/kg of XRP 2868 every 6 h. A sigmoid dose-response model was used to estimate the doses (mg/kg/24 h) required to achieve a net bacteriostatic affect over 24 h. MICs ranged from 0.06 to 0.25 μg/ml. The 24-h AUC/MICs for each static dose (20.7 to 252 mg/kg/day) varied from 3 to 70. Mean 24-h AUC/MICs ± standard deviations (SDs) for S. pneumoniae and S. aureus isolates were 14 ± 10 and 31 ± 16, respectively. Beta-lactam and macrolide resistance did not alter the magnitude of AUC/MIC required for efficacy.

scholarly journals In Vivo Pharmacodynamic Characterization of a Novel Odilorhabdin Antibiotic, NOSO-502, against Escherichia coli and Klebsiella pneumoniae in a Murine Thigh Infection Model

2018 ◽  
Vol 62 (9) ◽  
Author(s):  
Miao Zhao ◽  
Alexander J. Lepak ◽  
Karen Marchillo ◽  
Jamie VanHecker ◽  
David R. Andes
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Subcutaneous Administration ◽  
Dose Fractionation ◽  
Infection Model ◽  
Pharmacokinetic Studies ◽  
Time Curve ◽  
Content Type ◽  
The Mean

ABSTRACT NOSO-502 is a novel odilorhabdin antibiotic with potent activity against Enterobacteriaceae. The goal of these studies was to determine which pharmacokinetic/pharmacodynamic (PK/PD) indices and magnitude best correlated with efficacy in the murine thigh infection model. Six Escherichia coli and 6 Klebsiella pneumoniae isolates were utilized. MICs were determined using CLSI methods and ranged from 1 to 4 mg/liter. A neutropenic murine thigh infection model was utilized for all treatment studies. Single-dose plasma pharmacokinetics were determined in mice after subcutaneous administration of 7.81, 31.25, 125, and 500 mg/kg of body weight. Pharmacokinetic studies exhibited peak concentration (Cmax) values of 1.49 to 84.6 mg/liter, area under the concentration-time curve from 0 h to infinity (AUC0–∞) values of 1.94 to 352 mg · h/liter, and beta elimination half-lives of 0.41 to 1.1 h. Dose fractionation studies were performed using total drug doses of 7.81 mg/kg to 2,000 mg/kg fractionated into regimens of every 3 h (q3h), q6h, q12h, or q24h. Nonlinear regression analysis demonstrated that AUC/MIC was the PK/PD parameter that best correlated with efficacy (R2, 0.86). In subsequent studies, we used the neutropenic murine thigh infection model to determine the magnitude of NOSO-502 AUC/MIC needed for the efficacy against a diverse group of Enterobacteriaceae. Mice were treated with 4-fold-increasing doses (range, 3.91 to 1,000 mg/kg) of NOSO-502 every 6 h. The mean 24-h free-drug AUC/MIC (fAUC)/MIC) magnitudes associated with net stasis and 1-log kill endpoint for K. pneumoniae were 4.22 and 17.7, respectively. The mean fAUC/MIC magnitude associated with net stasis endpoint for E. coli was 10.4. NOSO-502 represents a promising novel, first-in-class odilorhabdin antibiotic with in vivo potency against Enterobacteriaceae.

scholarly journals Simultaneous Administration of 2-Aminoethyl Diphenylborinate and Chloroquine Reverses Chloroquine Resistance in Malaria Parasites

2015 ◽  
Vol 59 (5) ◽  
pp. 2890-2892 ◽  
Author(s):  
Ehab Mossaad ◽  
Wakako Furuyama ◽  
Masahiro Enomoto ◽  
Satoru Kawai ◽  
Katsuhiko Mikoshiba ◽  
...  
Keyword(s):  
Chloroquine Resistance ◽  
Infection Model ◽  
Simultaneous Administration ◽  
Plasmodium Chabaudi ◽  
Content Type ◽  
Mouse Infection Model ◽  
Complete Reversal ◽  
The Mean

ABSTRACTA nearly complete reversal of chloroquine (CQ) resistance in the CQ-resistantPlasmodium falciparumK-1 strain, with a significant decrease in the mean ± standard deviation (SD) 50% inhibitory concentration (IC50) from 1,050 ± 95 nM to 14 ± 2 nM, was achievedin vitroby the simultaneous administration of 2-aminoethyl diphenylborinate (2-APB). The CQ resistance-reversing activity of 2-APB, which showed the same efficacy as verapamil, was also observed in anin vivomouse infection model with the CQ-resistantPlasmodium chabaudiAS(30CQ) strain.

scholarly journals Atovaquone and ELQ-300 Combination Therapy as a Novel Dual-Site Cytochromebc1Inhibition Strategy for Malaria

2016 ◽  
Vol 60 (8) ◽  
pp. 4853-4859 ◽  
Author(s):  
Allison M. Stickles ◽  
Martin J. Smilkstein ◽  
Joanne M. Morrisey ◽  
Yuexin Li ◽  
Isaac P. Forquer ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Acute Infection ◽  
Quinone Reductase ◽  
Infection Model ◽  
Combination Therapies ◽  
Content Type ◽  
Infection Models ◽  
Dual Site ◽  
High Parasitemia

ABSTRACTAntimalarial combination therapies play a crucial role in preventing the emergence of drug-resistantPlasmodiumparasites. Although artemisinin-based combination therapies (ACTs) comprise the majority of these formulations, inhibitors of the mitochondrial cytochromebc1complex (cytbc1) are among the few compounds that are effective for both acute antimalarial treatment and prophylaxis. There are two known sites for inhibition within cytbc1: atovaquone (ATV) blocks the quinol oxidase (Qo) site of cytbc1, while some members of the endochin-like quinolone (ELQ) family, including preclinical candidate ELQ-300, inhibit the quinone reductase (Qi) site and retain full potency against ATV-resistantPlasmodium falciparumstrains with Qosite mutations. Here, we provide the firstin vivocomparison of ATV, ELQ-300, and combination therapy consisting of ATV plus ELQ-300 (ATV:ELQ-300), usingP. yoeliimurine models of malaria. In our monotherapy assessments, we found that ATV functioned as a single-dose curative compound in suppressive tests whereas ELQ-300 demonstrated a unique cumulative dosing effect that successfully blocked recrudescence even in a high-parasitemia acute infection model. ATV:ELQ-300 therapy was highly synergistic, and the combination was curative with a single combined dose of 1 mg/kg of body weight. Compared to the ATV:proguanil (Malarone) formulation, ATV:ELQ-300 was more efficacious in multiday, acute infection models and was equally effective at blocking the emergence of ATV-resistant parasites. Ultimately, our data suggest that dual-site inhibition of cytbc1is a valuable strategy for antimalarial combination therapy and that Qisite inhibitors such as ELQ-300 represent valuable partner drugs for the clinically successful Qosite inhibitor ATV.

The paradoxical in vivo activity of β-lactams against metallo-β-lactamase-producing Enterobacterales is not restricted to carbapenems

2020 ◽  
Author(s):  
Kamilia Abdelraouf ◽  
Sergio Reyes ◽  
David P Nicolau
Keyword(s):  
Infection Model ◽  
Murine Models ◽  
Mueller Hinton ◽  
Fold Reduction ◽  
Testing Medium ◽  
Zinc Concentrations ◽  
Mueller Hinton Broth ◽  
Positive Controls

Abstract Background Using murine models of infection, we previously reported the potent in vivo activity of carbapenems against MBL-producing Enterobacterales despite the observed resistance in vitro. In the current study, we examined the in vivo activity of a cefepime human-simulated regimen against MBL-producing Enterobacterales in a murine thigh infection model. Methods A population of clinical isolates and isogenic engineered MBL-producing Enterobacterales transformants expressing MBLs but no detectable cefepime-hydrolysing serine β-lactamases were utilized. KPC-producing isolates were included as positive controls. Cefepime, piperacillin/tazobactam and meropenem MICs were determined using broth microdilution in conventional CAMHB and EDTA-supplemented (zinc-limited) broth. In vivo efficacy of a cefepime human-simulated regimen (2 g q8h as a 2 h infusion) was determined in the neutropenic murine thigh infection model against the test strains. Efficacy was measured as the change in log10 cfu/thigh at 24 h compared with 0 h controls. Results MBL-producing Enterobacterales strains were found to be cefepime, piperacillin/tazobactam and meropenem non-susceptible in conventional broth. Supplementation with EDTA at a concentration of 300 mg/L resulted in multi-fold reduction in the MICs and restoration of susceptibility. In accordance with the MICs generated in zinc-limited broth, administration of a cefepime human-simulated regimen was associated with substantial bacterial reductions among mice infected with MBL-producing Enterobacterales. Absence of MIC reduction in zinc-limited broth and lack of efficacy among mice infected with KPC-producing isolates were observed. Conclusions For MBL-producing Enterobacterales, susceptibility testing with Mueller–Hinton broth, a zinc-rich testing medium, is flawed since it does not recapitulate the host environment, in which zinc concentrations are low.

scholarly journals Efficacy of Humanized Carbapenem and Ceftazidime Regimens against Enterobacteriaceae Producing OXA-48 Carbapenemase in a Murine Infection Model

2013 ◽  
Vol 58 (3) ◽  
pp. 1678-1683 ◽  
Author(s):  
Dora E. Wiskirchen ◽  
Patrice Nordmann ◽  
Jared L. Crandon ◽  
David P. Nicolau
Keyword(s):  
Wild Type Strain ◽  
Treatment Options ◽  
Infection Model ◽  
Wild Type ◽  
Content Type ◽  
Phenotypic Profile ◽  
Infection Models ◽  
The Relationship ◽  
Growth Controls

ABSTRACTEnterobacteriaceaeproducing the OXA-48 carbapenemase are emerging worldwide, leaving few treatment options. Efficacy has been demonstratedin vivowith ceftazidime against a ceftazidime-susceptible OXA-48 isolate but not with imipenem despite maintaining susceptibility. The relationship between phenotype andin vivoefficacy was assessed for OXA-48 producers using humanized regimens of 2 g doripenem every 8 h (q8h; 4 h infusion), 1 g ertapenem q24h, 2 g ceftazidime q8h (2 h inf), and 500 mg levofloxacin q24h. Each regimen was evaluated over 24 h against an isogenic pair (wild-type and OXA-48Klebsiella pneumoniaestrains) and six clinical OXA-48 isolates with and without other extended-spectrum β-lactamases in immunocompetent and neutropenic murine thigh infection models. Efficacy was determined using the change in bacterial density versus 24-h growth controls in immunocompetent studies and 0-h controls in neutropenic studies. Bacterial reductions of ≥1 log CFU were observed with all agents for the wild-type strain. Consistent with low MICs, ceftazidime and levofloxacin exhibited efficacy against the isogenic OXA-48 strain, whereas doripenem did not, despite having a susceptible MIC; no activity was observed with ertapenem, consistent with a resistant MIC. Similar trends were observed for the clinical isolates evaluated. Ceftazidime, levofloxacin, and ertapenem efficacy against isogenic and clinical OXA-48-producing strains correlated well with phenotypic profiles and pharmacodynamic targets, whereas efficacy with doripenem was variable over the MIC range studied. These data suggest that carbapenems may not be a reliable treatment for treating OXA-48 producers and add to previous observations with KPC and NDM-1 suggesting that genotype may better predict activity of the carbapenems than the phenotypic profile.

Sign in / Sign up

Export Citation Format

Share Document