Antibacterial activity of Ro 17-2301 and other antimicrobial agents against cefotaxime-resistant aerobic...

The in vitro activity of Ro 17-2301 was determined and compared with those of aztreonam, ceftazidime, amikacin, and piperacillin against 141 cefotaxime-resistant gram-negative bacilli. Ro 17-2301 was bactericidal, and its activity against the majority of these organisms was equal or superior to those of ceftazidime, aztreonam, and piperacillin. An inoculum effect of Ro 17-2301 and aztreonam for many Pseudomonas aeruginosa and Enterobacter spp. isolates was demonstrated.