ATC Vet code: QJ01MA93
Pharmacotherapeutic group: antibacterials for systemic use
Marbofloxacin is a synthetic, bactericidal antimicrobial, belonging to the fluoroquinolone group, which acts by inhibition of DNA gyrase. It has a broad-spectrum activity in vitro against Gram-positive bacteria and Gram-negative bacteria. Between 2009 and 2013, the activity of marbofloxacin against Pasteurella multocida (n=444) and Escherichia coli (n= 1226) isolated from swine diseases in Europe was for P. multocida: MIC range: 0.004-1 μg/ml, MIC50: 0.013µg/ml MIC90: 0.028μg/ml, for E. coli (digestive infections): MIC range 0.008-64µg/ml; MIC50:0.026µg/ml; MIC90:0.681µg/ml, for E. coli (MMA syndrome): MIC range 0.015-16µg/ml; MIC50:0.024µg/ml; MIC90:0.475µg/ml. Marbofloxacin MIC distribution among E. coli strains isolated from digestive or MMA syndrome are similar with a trimodal distribution.
The clinical breakpoints defined for marbofloxacin are S ≤ 1 µg/mL, I = 2 µg/mL and R ≥ 4 µg/mL for Pasteurellaceae according to the “Comité de l’Antibiogramme de la Société Française de Microbiologie” (=French Society of Microbiology) (CA-SFM 2013).
Between 2009 and 2012, the activity of marbofloxacin against Actinobacillus pleuropneumoniae (n=157) isolated from swine diseases in Europe was: MIC range: 0.015-2µg/mL, MIC50: 0.03µg/mL, MIC90: 0.06µg/mL
The activity of marbofloxacin against the target bacterial species is bactericidal concentration-dependent. A decrease of susceptibility of Campylobacter spp. against fluoroquinolones was observed since 1999.
Resistance to fluoroquinolones occurs by chromosomal mutation with three mechanisms: decrease of the bacterial wall permeability, expression of efflux pump or mutation of enzymes responsible for molecule binding. To date, only sporadic cases have been reported for plasmid mediated fluoroquinolone resistance in animals. Depending on the underlying resistance mechanism cross-resistance to other (fluoro)quinolones and co-resistance to other antimicrobial classes can occur.
After administration of an intramuscular dose of 8 mg/kg, the following mean pharmacokinetic parameters were observed:
Cmax=maximal plasmatic concentration; Tmax=mean observed occurrence time of the Cmax; AUCINF=area under the concentration-time curve extrapolated to infinity; T½λz=mean elimination half-life;F mean absolute bioavailability; nc: not calculated
Marbofloxacin is extensively distributed. Uterus tissue concentrations in sows reach Cmax of 9.346 µg/g in the uterine body observed at Tmax of 1.00 h after administration and the AUC last was 105.4 µg.h/g. Binding to plasma proteins is weak, about 4%. In pigs, the elimination is predominantly as the active form in urine and faeces.
In the studies performed, marbofloxacin was eliminated slightly faster in post-weaning piglets than in heavier animals.