Comparative in vitro antibacterial activities of two new oral cephalosporins, ceftetrame (Ro 19-5247) and cefetamet (Ro 15-8074)

ME1207 (pivaloyloxymethyl ester of ME1206) is a new oral cephalosporin. ME1206 is (6R,7R)-7-[(Z)-2-(2-aminothiazol-4-yl)-2-(methoxyimino)- acetamido]-3-[(Z)-2-(4-methylthiazol-5-yl)-ethyl]-cephem-4-carboxy lic acid. The susceptibilities of about 1,600 clinical isolates to ME1206 were determined by the agar dilution method. ME1206 showed a broad spectrum of activity against gram-positive and gram-negative bacteria. ME1206 was more active than cefaclor, T-2525, and cefixime against Staphylococcus aureus and Staphylococcus epidermidis. Against gram-negative bacteria, the activity of ME1206 was comparable with that of T-2525, but ME1206 was less active than cefixime. Against Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria gonorrhoeae, ME1206 had high activity (MIC, less than or equal to 0.05 microgram/ml). ME1206 was stable against various beta-lactamases, except beta-lactamases from Providencia rettgeri, Pseudomonas cepacia, and Escherichia coli W3630 (Rms213). The 50% effective doses of ME1207 after oral administration against systemic infections in mice were comparable with those of T-2588 against gram-negative bacteria and about one-fourth that of T-2588 against Staphylococcus aureus Smith.

mentioning

confidence: 99%

In vitro and in vivo antibacterial activities of ME1207, a new oral cephalosporin

Tamura¹,

Okamoto²,

Yoshida³

et al. 1988

“…Cefetamet is active against a large number of gramnegative microorganisms; at least 22 different species have been shown to be susceptible (1,4,5). T. pallidum can now be added to this list.…”

Section: Discussionmentioning

confidence: 99%

“…In vitro, the active metabolite cefetamet is especially effective against gram-negative microorganisms; it is also active against a few gram-positive organisms (1,4,5). In vivo, cefetamet has been successfully used to treat pyelonephritis in rats and septicemia in mice (1).…”

mentioning

confidence: 99%

Effects of cefetamet (Ro 15-8074) on Treponema pallidum and experimental syphilis

Fitzgerald

1992

Cefetamet pivoxil (Ro 15-8075) is a newly developed, expanded-spectrum cephalosporin that is orally active.In vitro, the active form, cefetamet (Ro 15-8074),-at a concentration of 0.05 ;Lg/ml killed and lysed Treponema paUlidum. Rabbit serum did not diminish its effectiveness. The antibiotic rapidly entered the circulation following intramuscular inection into rabbits, attaining its highest levels of 24 to 37 ,ug/ml within 10 to 30 min.Animals were infected intradermally with T. paUlidum and then treated with different doses of cefetamet.Accelerated healing was detected following treatment with 15 and 30 mg/kg of body weight. The antibiotic was also effective in killing organisms that had disseminated to distant tissues. In three separate sets of experiments, rabbits were infected with treponemes and then treated with cefetamet intramuscularly at 1, 15, or 30 mg/kg as follows: (i) after lesions had just become clinically apparent, (ii) after lesions were enlarged and well developed, or (iii) prior to the appearance of clinical lesions. Antibiotic effectiveness was determined by sacrificing the animals 1 week after antibiotic treatment and exawining splenic tissue for residual, disseminated treponemes. Cefetamet was treponemicidal in all three situations. Maximum effects occurred when the antibiotic was injected before lesions had become clinically apparent (incubation period). These results suggest that cefetamet pivoxil might be useful for treating syphilitic infections.

“…Cefaclor is active against gram-positive and some gram-negative bacteria but is hydrolyzed by various f-lactamases (13). Cefixime and cefteram (T-2525) (2,12,14) have good activity against gram-negative bacteria and streptococci and are not hydrolyzed readily by various P-lactamases, but these compounds have relatively low activities against staphylococci (2,6,12,14).…”

mentioning

confidence: 99%

“…BMY-28232 and BMY-28271 (the acetoxyethyl ester of BMY-28232) were synthesized at the Tokyo Research Center of Bristol Myers Research Institute, Ltd., Tokyo, Japan.-The other antimicrobial agents used in this study were obtained from the indicated sources: cefixime, Fujisawa Pharmaceutical Co., Ltd., Osaka, Japan; cefteram (T-2525, Ro 19-5247) and cefteram pivoxil (T-2588) (2,12,14), Toyama Chemical Co., Ltd., Tokyo, Japan; cefaclor, Shionogi Pharmaceutical Co., Ltd., Osaka, Japan; benzylpenicillin, Meiji Seika Kaisha, Ltd., Tokyo, Japan; cephaloridine, Nihon Glaxo Co., Ltd., Tokyo, Japan; and methicillin, Banyu Pharmaceutical Co., Ltd., Tokyo, Japan. Organisms. The bacterial strains used in this study were recent clinical isolates from various hospitals in Japan.…”

mentioning

confidence: 99%

Antimicrobial activity and stability to beta-lactamase of BMY-28271, a new oral cephalosporin ester

Matsui¹,

Hiraoka²,

Inoue³

et al. 1990

BMY-28271, the acetoxyethyl ester of BMY-28232, 7-[(Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3(Z) -propen-1-yl-3- cephem-4-carboxylic acid, is a new oral cephalosporin. BMY-28232 has a widely expanded spectrum with high activity against gram-positive and gram-negative bacteria. BMY-28232 is far more active than cefixime or cefteram against Staphylococcus aureus and Staphylococcus epidermidis. Against gram-negative bacteria, the activity of BMY-28232 was comparable to or somewhat weaker than that of cefixime or cefteram. BMY-28232 was a poor substrate for various beta-lactamases. Orally administered BMY-28271 had a good therapeutic effect on systemic infections with S. aureus and some gram-negative bacteria in mice. Oral BMY-28271 was efficacious against S. aureus Smith infection: the efficacy of BMY-28271 was 80 to 90 times higher than that of cefixime or cefteram.