In vitro susceptibilities of 185 penicillin-susceptible and -resistant pneumococci to WY-49605 (SUN/SY 5555), a new oral penem, compared with those to penicillin G, amoxicillin, amoxicillin-clavulanate, cefixime, cefaclor, cefpodoxime, cefuroxime, and cefdinir.
In vitro susceptibility of 185 penicillin-susceptible and -resistant pneumococci to WY-49605, a new oral penem, was compared with susceptibility to penicillin G, amoxicillin with and without clavulanate, cefixime, cefaclor, cefpodoxime, cefuroxime, and cefdinir. WY-49605 yielded MICs for 50 and 90% of the strains tested (MIC50 and MIC90, respectively) of 0.03 and 0.06, 0.125 and 0.5, and 0.5 and 1.0 micrograms/ml, respectively, against penicillin-susceptible, intermediately resistant, and fully resistant strains, respectively. The MIC50 and MIC90 for both amoxicillin and amoxicillin-clavulanate were identical and approximately 1 doubling dilution higher than those for WY-49605 and were < or = 0.06 and 0.125, 0.25 and 1.0, and 1.0 and 1.0 micrograms/ml, respectively. Cephalosporin MIC90s were all significantly higher than those of the latter three compounds for intermediately resistant and fully resistant strains.
Spangler
S K
SK
Department of Pathology (Clinical Microbiology), Hershey Medical Center, Pennsylvania 17033.
Jacobs
M R
MR
Appelbaum
P C
PC
D000658:Amoxicillin / Q000494:pharmacology; D019980:Amoxicillin-Potassium Clavulanate Combination; D015780:Carbapenems / Q000494:pharmacology*; D002433:Cefaclor / Q000494:pharmacology; D000077525:Cefdinir; D020682:Cefixime; D002439:Cefotaxime / Q000031:analogs & derivatives / Q000494:pharmacology; D015296:Ceftizoxime / Q000031:analogs & derivatives / Q000494:pharmacology; D002444:Cefuroxime / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D002969:Clavulanic Acids / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D010400:Penicillin G / Q000494:pharmacology; D010403:Penicillin Resistance; D000097623:Cefpodoxime
D000658:Amoxicillin; D019980:Amoxicillin-Potassium Clavulanate Combination; D015780:Carbapenems; D002433:Cefaclor; D000077525:Cefdinir; D020682:Cefixime; D002439:Cefotaxime; D015296:Ceftizoxime; D002444:Cefuroxime; D002511:Cephalosporins; D002969:Clavulanic Acids; D010400:Penicillin G; D000097623:Cefpodoxime; C060114:SUN 5555