Grepafloxacin.

Grepafloxacin (OPC-17116) is a new once-daily fluoroquinolone antimicrobial agent which appears to have high tissue penetration and the wide spectrum of antimicrobial activity typical of this class of agents, but with improved activity against Gram-positive organisms, notably Streptococcus pneumoniae. The in vitro activity of grepafloxacin was similar to or slightly lower than that of ciprofloxacin against Enterobacteriaceae but better than that of ciprofloxacin against most Gram-positive organisms. In particular, grepafloxacin showed good activity against pathogens implicated in community-acquired pneumonia, with 4-fold higher potency than ciprofloxacin against S. pneumoniae, including penicillin-resistant strains. In animal studies, grepafloxacin did not induce convulsions when administered at high doses in conjunction with nonsteroidal anti-inflammatory agents. Grepafloxacin has a weak propensity for causing phototoxicity, similar to that of ciprofloxacin. In comparative clinical trials, grepafloxacin demonstrated similar efficacy to amoxicillin in community-acquired pneumonia, ofloxacin in pneumonia and chronic respiratory tract infection, and cefixime in uncomplicated gonococcal urethritis and gonococcal cervicitis. Grepafloxacin has also shown clinical efficacy in preliminary studies in patients with chlamydial endocervical infection or bacillary dysentery.