Cefovecin is a third generation cephalosporin with a broad-spectrum of activity against Gram-positive and Gram-negative bacteria. It differs from other cephalosporins in that it is highly protein bound and has a long duration of activity. As with all cephalosporins, the action of cefovecin results from the inhibition of bacterial cell wall synthesis; cefovecin has bactericidal activity.
Cefovecin exhibits in vitro activity against Staphylococcus pseudintermedius and Pasteurella multocida which are associated with canine and feline skin infections. Anaerobic bacteria such as Bacteroides spp. and Fusobacterium spp. collected from feline abscesses were shown to be susceptible. Porphyromonas gingivalis and Prevotella intermedia collected from canine periodontal disease were also shown to be susceptible. In addition, cefovecin exhibits in-vitro activity against Escherichia coli which is associated with canine and feline urinary tract infections.
Resistance to cephalosporins results from enzymatic inactivation (β-lactamase production) or from other mechanisms. Resistance may be chromosomal or plasmid-encoded and may be transferred if associated with transposons or plasmids. Cross resistance with other cephalosporins and other beta-lactam antibacterial agents can be observed. When applying a proposed microbiological breakpoint of S < 2 μg/ml, no resistance to cefovecin was detected in Pasteurella multocida, Fusobacterium spp or Porphyromonas spp. field isolates. When applying a proposed microbiological breakpoint of I < 4 μg/ml, cefovecin resistance in S. pseudintermedius and beta-haemolytic Streptococci isolates was less than 0.02% and 3.4% in Prevotella intermedia isolates. The percentage of cefovecin resistant isolates in E. coli, Prevotella oralis, Bacteroides spp. and Proteus spp. were 2.3%, 2.7%, 3.1% and 1.4%, respectively. The percentage of cefovecin resistant isolates in coagulase negative Staphylococci spp. (e.g. S. xylosus, S. schleiferi, S. epidermidis) is 9.5%. Pseudomonas spp., Enterococcus spp, and Bordetella bronchiseptica isolates are inherently resistant to cefovecin.
Cefovecin has unique pharmacokinetic properties with extremely long elimination half-lives in both dogs and cats.