In Vitro Pharmacodynamics of a Novel Ceftibuten-Clavulanate Combination Antibiotic against Enterobacteriaceae.
Antimicrob Agents Chemother
; 63(7)2019 07.
Article
en En
| MEDLINE
| ID: mdl-31061148
ABSTRACT
A novel antibiotic combination of the oral cephalosporin ceftibuten (CTB) and the ß-lactamase inhibitor clavulanate (CLA) is currently in development for urinary tract infections, including those caused by extended-spectrum-ß-lactamase (ESBL)-producing organisms. This study aimed to identify the pharmacodynamic index and magnitude of this index for CLA, when combined with a fixed CTB exposure (â¼59% free time above the CTB-CLA MIC) against ESBL-producing Escherichia coli and Klebsiella pneumoniae (CTB-CLA MICs of 0.25/0.125 to 1/0.5 µg/ml) using the in vitro chemostat model. Dose fractionation studies identified the time that free CLA concentrations remained above a threshold concentration (fT>threshold) to be the best pharmacodynamic index (R2 = 0.85) compared with the free area under the curve (AUC)/threshold ratio (R2 = 0.62) and free maximum concentration/threshold ratio (R2 = 0.37). For E. coli isolates, stasis and 1-log10 CFU reductions were achieved at 30.9 and 47.9% fT>CTB concentrations of the 21 CTB-CLA MIC (fT>MIC here), respectively. For K. pneumoniae isolates, stasis and 1-log10 CFU reductions were achieved at 51.9 and 92.0% fT>MIC, respectively. These data inform exposure requirements for CLA combined with CTB for optimizing pharmacodynamics against Enterobacteriaceae and should be useful in designing dosage regimens for this combination antibiotic.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Infecciones Urinarias
/
Ácido Clavulánico
/
Enterobacteriaceae
/
Ceftibuteno
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Antimicrob Agents Chemother
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos