What is it about?

Cefquinome is administered in horses for the treatment of respiratory infection caused by Streptococcus equi subsp. zooepidemicus, and septicemia caused by Escherichia coli. However, there have been no attempts to use cefquinome against Streptococcus equi subsp. equi (S. equi), the causative agent of strangles. Hence the objective of this study was to calculate an optimal dosage of cefquinome against S. equi based on pharmacokinetics and pharmacodynamics integration. Cefquinome (1.0 mg/kg) was administered by intravenous and intramuscular routes to six healthy thoroughbred foals. Serum cefquinome concentrations were determined by high-performance liquid chromatography. The in vitro and ex vivo antibacterial activity were determined from minimum inhibitory concentrations (MIC) and bacterial killing curves. The optimal dosage was calculated from the integration of pharmacokinetic parameters and area under the curve (AUC24h/MIC) values. Total body clearance and volume of distribution of cefquinome after intravenous administration were 0.06 L/h/kg and 0.09 L/kg, respectively. Following intramuscular administration, a maximum concentration of 0.73 μg/mL at 1.52 h (Tmax) and a systemic bioavailability of 37.45% were observed. The MIC of cefquinome against S. equi was 0.016 μg/mL. The ex vivo AUC24h/MIC values representing bacteriostatic, and bactericidal activity were 113.11, and 143.14 h, respectively. Whereas the %T > MIC for bactericidal activity was 153.34%. In conclusion, based on AUC24h/MIC values and pharmacokinetic parameters, cefquinome when administered by intramuscularly at a dosage of 0.53 mg/kg every 24 h, would be effective against infection caused by S. equi in foals. Further studies may be necessary to confirm its therapeutic efficacy in a clinical environment.

Featured Image

Perspectives

Although studies regarding the integration of PK/PD of cefquinome have been conducted previously in some animals, there have been no previous attempts to suggest an optimized dosage of cefquinome against S. equi in horses using PK/PD integration. So this study (1) determine the concentrations of cefquinome in serum and PK parameters following intravenous (IV) and intramuscular (IM) administration at a dose of 1 mg/kg in horses using high-performance liquid chromatography (HPLC); (2) provide the degree of serum protein binding; (3) estimate the in vitro and ex vivo antibacterial activity of cefquinome against S. equi; and (4) calculate the optimal dosage regimen for the infections caused by S. equi based on cefquinome PK/PD parameters.

Dr Biruk Tesfaye Birhanu
University of Notre Dame

Read the Original

This page is a summary of: Pharmacokinetic and pharmacodynamic integration for optimal dosage of cefquinome against Streptococcus equi subsp. equi in foals, Veterinary Research, October 2020, Springer Science + Business Media,
DOI: 10.1186/s13567-020-00853-2.
You can read the full text:

Read

Contributors

The following have contributed to this page