AFN-1252, a FabI inhibitor, demonstrates a Staphylococcus-specific spectrum of activity.

AFN-1252, a potent inhibitor of enoyl-acyl carrier protein reductase (FabI), inhibited all clinical isolates of Staphylococcus aureus (n = 502) and Staphylococcus epidermidis (n = 51) tested, including methicillin (meticillin)-resistant isolates, at concentrations of <or=0.12 microg/ml. In contrast, AFN-1252 was inactive (MIC(90), >4 microg/ml) against clinical isolates of Streptococcus pneumoniae, beta-hemolytic streptococci, Enterococcus spp., Enterobacteriaceae, nonfermentative gram-negative bacilli, and Moraxella catarrhalis. These data support the continued development of AFN-1252 for the treatment of patients with resistant staphylococcal infections.