BL-S786 (ceforanide), a new parenteral cephalosporin: in vitro studies.

BL-S786 (ceforanide) is a new cephalosporin which showed broad-spectrum activity in vitro against 453 clinical isolates. At a concentration of 3.12 mug/ml, it inhibited greater than 75% of isolates of Escherichia coli, Klebsiella spp., Proteus mirabilis, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae. Essentially no activity was observed against isolates of Serratia marcescens, and only minimal activity was observed against Enterobacter spp. Its activity was directly related to the size of the inoculum. The minimal bactericidal concentrations were similar to the minimal inhibitory concentrations for isolates of all organisms except S. aureus and S. pyogenes. The minimal bactericidal concentrations were considerably higher than the minimal inhibitory concentrations for these organisms.