In Vitro Activity of Gepotidacin against Gram-Negative and Gram-Positive Anaerobes.

Gepotidacin (formerly GSK2140944) is a first-in-class triazaacenaphthylene antibacterial currently in phase III clinical trials. When tested against Gram-negative (n = 333) and Gram-positive (n = 225) anaerobes by agar dilution, gepotidacin inhibited 90% of isolates at concentrations of 4 and 2 µg/mL, respectively. Given gepotidacin's in vitro activity against the anaerobic isolates tested, further study is warranted to better understand the utility of gepotidacin in the treatment of infections caused by clinically relevant anaerobic organisms.

Comparison of minimum inhibitory concentration results for gepotidacin obtained using agar dilution and broth microdilution methods.

Gepotidacin (GSK2140944) is a first in class, novel triazaacenaphthylene bacterial type II topoisomerase inhibitor in Phase 3 clinical development for the treatment of gonorrhea and uncomplicated urinary tract infections (acute cystitis). This study tested the equivalency of minimal inhibitory concentrations (MICs) obtained by two reference susceptibility testing methods, agar dilution and broth microdilution, for gepotidacin when tested against various gram-positive and gram-negative organisms. Equivalency, measured as the essential agreement >89.9%, was established between the two methods for determining gepotidacin susceptibility results against Staphylococcus spp., Streptococcus spp., and Escherichia coli. However, for Neisseria gonorrhoeae and Haemophilus influenzae, equivalency was not established. Agar dilution remains the sole dilution reference method for determining gepotidacin MICs against N. gonorrhoeae.