Eftersom moxifloxacin hos nogle grampositive bakterier hæmmer både topoisomerase II og IV med ens aktivitet, så kan disse bakterier dog kan være resistente mod andre quinoloner, men følsomme overfor moxifloxacin.
However, as moxifloxacin inhibits both topoisomerase II and IV with similar activity in some Gram-positive bacteria, such bacteria may be resistant to other quinolones, but susceptible to moxifloxacin.