IN-VITRO ACTIVITY OF CLINAFLOXACIN (CI-960) AND PD-131628-2 AGAINST ANAEROBIC-BACTERIA

The antimicrobial activities of two new quinolones, CI-960 and PD 1316 28-2 were determined against 339 strains of anaerobic bacteria and com pared to cefoxitin, imipenem and metronidazole. The NCCLS-approved Wad sworth agar dilution technique with Brucella-lysed blood agar was used throughout the study. Breakpoints of the new quinolones are 2 mg/L, a nd breakpoints for cefoxitin, imipenem and metronidazole are 32, 8 and 16 mg/L, respectively. CI-960 displayed excellent activity, inhibitin g all strains tested at 1 mg/L. PD 131628-2 inhibited 94% of Bacteroid es fragilis, 75% of other B. fragilis group isolates, 87% of Prevotell a spp, 79% of the Fusobacterium mortiferum-varium group, 74% of non-sp oring gram-positive bacilli, and 89-100% of Clostridium spp other than Clostridium difficile at 2 mg/L. None of the eight strains of C. diff icile was inhibited at 2 mg/L although they were inhibited at 4 mg/L. PD 131628-2 inhibited all strains of other Bacteroides spp, Porphyromo nas spp, and Fusobacterium nucleatum at less than or equal to 1 mg/L.