CS-023 (R-115685), a novel carbapenem with enhanced in vitro activity against oxacillin-resistant staphylococci and Pseudomonas aeruginosa.
OBJECTIVE
To compare the in vitro activities of the carbapenem, CS-023, four representative beta-lactam antibiotics and levofloxacin, against 970 Gram-positive or Gram-negative US clinical isolates.


METHODS
Susceptibilities of bacteria chosen for their varying levels of resistance to the comparator agents were determined by NCCLS microdilution methodology.


RESULTS
CS-023 exhibited activity comparable to that of imipenem against most Gram-positive isolates, but was approximately 8-fold more potent against oxacillin-resistant staphylococci. It was comparable to meropenem against most Gram-negative isolates, but was 4- to 8-fold more potent against five isolates of meropenem-resistant Pseudomonas aeruginosa.


CONCLUSIONS
If tissue and body fluid concentrations >8 mg/L can safely be achieved, further studies of CS-023 are warranted to determine its clinical efficacy.
Thomson
Kenneth S
KS
Center for Research in Anti-Infectives and Biotechnology, Department of Medical Microbiology and Immunology, Creighton University School of Medicine, Omaha, NE 68178, USA. kstaac@creighton.edu
Moland
Ellen Smith
ES
D000890:Anti-Infective Agents / Q000494:pharmacology; D001424:Bacterial Infections / Q000382:microbiology; D015780:Carbapenems / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D010068:Oxacillin / Q000494:pharmacology*; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013210:Staphylococcus / Q000187:drug effects*; D014481:United States
D000890:Anti-Infective Agents; D015780:Carbapenems; D010406:Penicillins; C492232:tomopenem; D010068:Oxacillin