Cefetamet (sodium)

Cefetamet (Ro 15-8074) sodium is a cephalosporin antibiotic and the active metabolite of Cefetamet pivoxil (HY-B1894A). Cefetamet sodium binds to bacterial penicillin-binding protein (PBP) (IC₅₀ for PBP3 in Escherichia coli W3110 is 2.5 μg/mL). Cefetamet sodium has significant activity against Gram-negative bacteria such as Enterobacteriaceae, Neisseria species, and Haemophilus influenzae, as well as Gram-positive bacteria such as Streptococcus. Cefetamet sodium kills and lyses Treponema pallidum. Cefetamet sodium can be used in the research of respiratory tract, urinary tract, ear, nose and throat infections, and syphilis^{[1][2][3][4][5]}. In Vitro:Cefetamet sodium exhibits high in vitro activity against most members of the Enterobacteriaceae, Haemophilus influenzae, Neisseria spp., and Streptococcus pneumoniae (MIC₉₀ ≤ 2 μg/mL)^[2].
Cefetamet sodium shows high in vitro activity against Enterobacteriaceae, Neisseria spp., Vibrio spp., Haemophilus influenzae and streptococci other than enterococci^[3].
Cefetamet sodium exhibits poor affinity for the PBPs of Staphylococcus aureus, with IC₅₀s of 90, >100, 52 and >100 μg/mL for PBP 1 to 4^[3].
Cefetamet (0.05-0.1 μg/mL; 24 h) sodium kills and lyses Treponema pallidum in vitro^[4].
In Vivo:Cefetamet (1-30 mg/kg; i.m.; once) sodium cures experimental syphilis in rabbits, with the best effect when administered before clinical manifestations^[4].