Efficacy of cefmenoxime in experimental group b streptococcal bacteraemia and meningitis

Cefmenoxime, a new semisynthetic cephalosporin, was evaluated in vitro and in vivo in comparison with penicillin G against a type III group B streptococcal strain. In vitro, the minimal inhibitory and minimal bactericidal concentrations of the two drugs were very close (≤2 dilutions). In-vivo studies using experimental bacteraemia and meningitis in newborn rats revealed that despite similar drug levels, cefmenoxime had significantly greater bactericidal titres in blood at 6-7 h after administration and bacterial clearance from blood was significantly faster with cefmenoxime than with penicillin G at the end of one day of treatment. In addition, all animals with cefmenoxime therapy had bactericidal titres in cerebrospinal fluid ≥ 1:8 at 1-2 h after administration, whereas most (67%) animals receiving penicillin G had titres < 1:8. However, overall efficacy of cefmenoxime was similar to that of penicillin G. These findings suggest that cefmenoxime may be an effective alternative against group B streptococcal infection.