Bioevaluation of the antibacterial flumequine for urinary tract use

The antimicrobial activity of flumequine (R-802) was characterized by in vitro and in vivo procedures. Assay of the minimal inhibitory concentrations for 321 recent clinical isolates revealed that 88% of the gram-negative bacteria were inhibited by an R-802 concentration of 6.2 mug/ml or less. Cross-resistance in laboratory-derived mutants of Proteus vulgaris was essentially complete for R-802, nalidixic acid, and oxolinic acid, although quantitative differences were evident. R-802 was more effective than either of these quinolone antibacterials in preventing the development of experimental murine pyelonephritis (P. vulgaris). R-802 and trimethoprim/sulfamethoxazole (1:5) were equally effective in resolving a P. mirabilis-induced prostatitis of rats.