ATCvet code: QJ01MA97
Pharmacodynamic properties
Mode of Action
The primary mode of action of the fluoroquinolones involves interaction with enzymes essential for major DNA functions such as replication, transcription and recombination. The primary targets for pradofloxacin are the bacterial DNA gyrase and topoisomerase IV enzymes. Reversible association between pradofloxacin and DNA gyrase or DNA topoisomerase IV in the target bacteria results in inhibition of these enzymes and rapid death of the bacterial cell. The rapidity and extent of bacterial killing are directly proportional to the drug concentration.
Antibacterial Spectrum
Although pradofloxacin has in-vitro activity against a wide range of Gram-positive and Gram-negative organisms, including anaerobic bacteria, this veterinary medicinal product should only be used for the approved indications (see section: Indications for use, specifying the target species) and in accordance with the prudent use recommendations in section: special precautions for use of this SPC
MIC-Data
Bacterial Species | Number of strains | MIC50 (mcg/ml) | MIC90 (mcg/ml) | MIC range (mcg/ml) |
Pasteurella multocida - respiratory tract infections (RTI)1 | 64 | 0.008 | 0.008 | 0.004 - 0.03 |
Pasteurella multocida– wound infections2 | 42 | 0.008 | 0.008 | 0.004 - 0.03 |
Escherichia coli - respiratory tract infections (RTI)1 | 22 | 0.015 | 4 | 0.008 - 8 |
Staphylococcus intermedius group (including S. pseuintermedius) - respiratory tract infections (RTI)1 | 25 | 0.12 | 2 | 0.008-4 |
Staphylococcus intermedius group (including S. pseudintermedius) – wound infections2 | 20 | 0.03 | 2 | 0.15-2 |
1 Data collected between 2017–2018 2 Data collected between 2021-2022 The bacteria were isolated from clinical cases in Belgium, Czech Republic, France, Germany, Hungary, Italy, the Netherlands, Poland, Spain Sweden, Switzerland and UK.
Clinical breakpoints established by CLSI in 2024 (7th edition) for pradofloxacin in cats for respiratory tract infections are:
Organism | Minimum Inhibitory Concentration breakpoints of pradofloxacin (mcg/ml) |
Susceptible | intermediate | resistant |
E.coli | ≤0.25 | 0.5-1 | ≥2 |
S.pseudintermedius | ≤0.25 | 0.5-1 | ≥2 |
Types and Mechanisms of Resistance
Resistance to fluoroquinolones has been reported to arise from five sources, (i) point mutations in the genes encoding for DNA gyrase and/or topoisomerase IV leading to alterations of the respective enzyme, (ii) alterations of drug permeability in Gram-negative bacteria, (iii) efflux mechanisms, (iv) plasmid mediated resistance and (v) gyrase protecting proteins. All mechanisms lead to a reduced susceptibility of the bacteria to fluoroquinolones. Cross-resistance within the fluoroquinolones class of antimicrobials is common.
Pharmacokinetic particulars
In laboratory studies the bioavailability of pradofloxacin was reduced in fed cats compared to fasted animals. However in clinical studies feeding did not reveal any impact on the treatment effect.
After oral administration of the veterinary medicinal product to cats at the recommended therapeutic dose, absorption of pradofloxacin is rapid, reaching peak concentrations of 2.1 mg/l within 1 hour. The bioavailability of the veterinary medicinal product is at least 60%. Repeated dosing shows no impact on the pharmacokinetic profile, (accumulation index = 1.2). In vitro plasma protein binding is low (30%). The high volume of distribution (Vd) >4 l/kg body weight indicates good tissue penetration. Pradofloxacin is eliminated from serum with a terminal half-life of 7 hours. The major elimination pathway in cats is glucuronidation. Pradofloxacin is cleared from the body at 0.28 l/h/kg.