E. Gradelski et al., Comparative killing kinetics of the novel des-fluoro(6) quinolone BMS-284756, fluoroquinolones, vancomycin and beta-lactams, INT J ANT A, 18(1), 2001, pp. 43-48
The primary bactericidal classes used therapeutically as single agents, are
the quinolones and the cell-wall active agents. In this study, their rates
of killing were compared. The des-fluoro(6) quinolone BMS-284756 (T-3811ME
), fluoroquinolones (trovafloxacin, levofloxacin) and cell wall-active agen
ts (beta -lactams, vancomycin) were evaluated against Enterobacteriaceae, S
taphylococcus aureus, streptococci, and Enterococcus faecalis. Time-kill an
alysis was done at 10 x the MIC, using Mueller-Hinton broth (supplemented w
ith 7% lysed horse blood for Streptococcus pneumoniae and the viridans stre
ptococci), or Brain Heart Infusion broth for beta -haemolytic streptococci.
Using a 3-log(10) decrease in viable count as an index of bactericidal act
ivity, BMS-284756 and the fluoroquinolones killed Enterobacteriaceae rapidl
y, requiring < 2 h versus greater than or equal to 6 h for beta -lactams. T
he staphylococcal cell counts generally decreased more rapidly with quinolo
ne exposure. compared with those treated with vancomycin or the beta -lacta
ms. The antimicrobial agents killed streptococci and enterococci more slowl
y, requiring > 6 It to decrease the viable count by 99.9%. In summary, BMS-
284756 killing rates are similar to those of recent fluoroquinolones and ar
e bacterial group-dependent. Overall, the quinolones are more rapidly bacte
ricidal than vancomycin and the beta -lactam antibiotics. (C) 2001 Elsevier
Science B.V. and International Society of Chemotherapy. All rights reserve
d.