In vitro comparison activity of OPC-17116, a new fluoroquinolone, against more than 5,000 recent clinical isolates from five medical centers.

The in vitro activity of OPC-17116, a new fluoroquinolone, was compared with those of ciprofloxacin, ofloxacin and cefixime. A total of 5,231 fresh clinical isolates from five geographically separate US medical centers were tested. The primary results of this study are: 1. OPC-17116 is very active against Enterobacteriaceae [MIC90s, 0.015-1 microgram/ml, except Providencia rettgeri (MIC90, > 8 micrograms/ml)], 2. among nonenteric Gram-negative bacilli (e.g. Xanthomonas maltophilia, MIC90, 2 micrograms/ml) and Gram-positive cocci (e.g. oxacillin-susceptible staphylococci, MIC90s, 0.12-0.5 microgram/ml) OPC-17116 demonstrated higher activity than ciprofloxacin or ofloxacin, 3. the quinolones were more active than cefixime against most of the species tested, especially against Gram-positive and non-enteric Gram-negative organisms. The results of this study, associated with prior documented favorable qualities, support continued investigation of OPC-17116 for clinical use.