In vitro and in vivo antibacterial activities of ME1207, a new oral cephalosporin.
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.
Tamura
A
A
Episome Institute, Gunma, Japan.
Okamoto
R
R
Yoshida
T
T
Yamamoto
H
H
Kondo
S
S
Inoue
M
M
Mitsuhashi
S
S
D000284:Administration, Oral; D000818:Animals; D001419:Bacteria / Q000187:drug effects*; D002352:Carrier Proteins; D002511:Cephalosporins / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases / Q000378:metabolism
D002352:Carrier Proteins; D002511:Cephalosporins; C057710:cefditoren pivoxil; D001618:beta-Lactamases