BL-S 640, a Cephalosporin with a Broad Spectrum of Antibacterial Activity: Properties In Vitro

The in vitro antibacterial activity of nine cephalosporins (cephalothin, cephaloridine, cephalexin, cefazolin, cefamandole, cefuroxime, cefatrizine, cefoxitin, and cefazaflur) was determined against 344 strains ofEnterobacteriaceae and 99 nonfermentative gram-negative bacilli. Cefamandole, cefazaflur, and cefuroxime were the most active cephalosporins against the Enterobacteriaceae (with the exception of Serratia marcescens). However, cefoxitin was the only cephalosporin that inhibited all 30 S. marcescens strains in a concentration of 16 ,g/ml and was by far the most active compound against selected cephalothin-resistant strains ofEscherichia coli, Klebsiella, and Proteus mirabilis. Acinetobacter spp. were inhibited best by cefuroxime, but none of the cephalosporins had appreciable activity against the Pseudomonas spp.

mentioning

confidence: 99%

Comparison of the Antibacterial Activity of Nine Cephalosporins Against Enterobacteriaceae and Nonfermentative Gram-Negative Bacilli

Verbist¹

1976

“…At 25 C, half-life times were 6 h at pH 8.0, 12 h at pH 7.0, and about 30 h at pH 6.0. At pH 5.0 no loss in activity could be detected after 24 h. DISCUSSION BL-S640 is known to display considerable antibacterial activity against a variety of both gram-negative and gram-positive clinical isolates (6,10). In the present study the antibiotic was found to be less active than three of the control compounds against S. aureus, but nevertheless more active than cephalexin.…”

Section: Resultsmentioning

confidence: 44%

“…However, most derivatives have little or no effect against the more resistant Enterobacteriaceae such as members of the genera Enterobacter, Serratia, Providencia, and indole-positive Proteus. Preliminary studies with BL-S640 suggest good activity against all these isolates except Serratia, which is highly resistant (6,10). The compound is well adsorbed orally and parenterally, and its therapeutic efficacy in rodents infected systemically with a variety of pathogenic bacteria appears to be significantly greater than would be predicted on the basis of its comparative activity in vitro (7).…”

mentioning

confidence: 99%

In Vitro Activity of BL-S640 Against Gram-Negative Bacilli and Staphylococcus aureus Compared with Activity of Four Other Semisynthetic Cephalosporins

Vuye

Pijck²,

Soep³

1976

The in vitro activity of BL-S640 (cefatrizine) was determined against 674 recent clinical isolates of Staphylococcus aureus and Enterobacteriaceae. Activity against S. aureus was less than that of cephapirin, cephalothin, and cefazolin, but greater than that of cephalexin. Activity against gram-negative isolates was variable: BL-S640 was slightly less potent than cefazolin against Escherichia coli and Klebsiella, but more active than the other compounds. As for the more resistant gram-negative genera, BL-S640 was significantly superior to the control cephalosporins. The effect of inoculum size on the antibacterial activity was moderate for most organisms except Enterobacter, Providencia stuartii, and indole-positive Proteus, the median minimal inhibitory concentrations of which were 6 to 27 times lower when determined with a 10-4-diluted culture compared with the undiluted one. The stability in aqueous solution at 37 C was remarkably high at the lower pH values, but low at the neutral point.

“…A similar situation was found with an Acinetobacter isolate. DISCUSSION Earlier publications (1,2,6,8,9) have suggested that cefatrizine is an agent that would extend the spectrum of oral and parenteral cephalosporins, but these studies compared its activity with that of older agents and not with that of cefamandole, cefuroxime, and cefoxitin, which have an expanded spectrum of activity (3)(4)(5). Although cefatrizine has excellent stability com- …”

Section: Resultsmentioning

confidence: 99%

Cefatrizine Activity Compared with That of Other Cephalosporins

Neu

1979

Cefatrizine, a new orally administered cephalosporin, was tested against 400 clinical isolates. Cefatrizine had excellent activity against gram-positive cocci, inhibiting all except enterococci at minimal inhibitory concentrations below 1 μg/ml. Cefatrizine inhibited the majority of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis , and Salmonella at concentrations below 12.5 μg/ml. Although cefatrizine was not hydrolyzed by many β-lactamases, it did not inhibit a number of strains of Enterobacter, Serratia , or indole-positive Proteus . Cefatrizine was more active than cephalothin or cephalexin against E. coli, Klebsiella, Enterobacter, Citrobacter, Salmonella , and Shigella . Its overall activity was less than that of cefoxitin against strains resistant to cephalothin, but its activity against cephalothin-susceptible strains was equivalent to that of cefamandole.