In vitro activity of biapenem (L-627), a new carbapenem, against anaerobes.

We tested 441 clinical strains of anaerobes by using a broth microdilution method to determine the in vitro activity of biapenem for comparison with those of other agents. Biapenem had activity comparable to those of imipenem and meropenem against all groups of anaerobes with MICs for 90% of the strains tested of 0.06 to 2 micrograms/ml. Against the Bacteroides fragilis group, biapenem was more active than ampicillin-sulbactam, ticarcillin-clavulanate, piperacillin, cefoxitin, cefotaxime, and ceftriaxone. Biapenem was also active against all of the B. capillosus, Prevotella, Clostridium, and Eubacterium strains and anaerobic cocci tested. Against all of the anaerobes tested, biapenem was 32- and 4-fold more active than clindamycin and metronidazole, respectively. These data indicate broad-spectrum activity by biapenem against anaerobes.