In vitro evaluation of difloxacin (A-56619), A-56620, and other 4-quinolones against isolates from cancer patients.

The in vitro activity of two new quinolones, difloxacin and A-56620, was compared with that of other quinolones against isolates obtained from bacteremic cancer patients. Both agents had a broad antimicrobial spectrum which included both gram-positive and gram-negative organisms. A-56620 had lower MIC values against most organisms tested than difloxacin, and its activity was comparable to that of ciprofloxacin.