In-vitro activity of grepafloxacin, a new fluoroquinolone, against mycoplasmas

The in-vitro activity of grepafloxacin, a new oral fluoroquinolone antibiot ic, was compared with those of three other fluoroquinolones and two unrelat ed antimicrobials, doxycycline and erythromycin, against various Mycoplasma spp. For 65 mycoplasma and 42 ureaplasma strains, grepafloxacin (MIC range 0.03-2 mg/L) was some two to 16 times more active than ofloxacin and cipro floxacin, showing similar activity to that of sparfloxacin. MBCs of grepafl oxacin increased two- to 16-fold when compared with MICs and were comparabl e to those of sparfloxacin, and lower than those of ofloxacin and ciproflox acin.