Animal experiment:

Mice: For neutropenic pharmacokinetic studies, at 3 h postinoculation (0 h), groups of 48 infected mice are administered GSK2140944 s.c. in single doses of 6.25, 50, or 200 mg/kg. Blood samples are collected from groups of six mice at 5 min and 0.25, 0.5, 1, 1.5, 2, 3, and 4 h postdose for 6.25- or 50-mg/kg doses and 5 min and 0.25, 0.5, 1, 1.5, 2, 4, and 6 h postdose for the 200-mg/kg dose via cardiac puncture[4].

Gepotidacin (GSK2140944) is a novel triazaacenaphthylene bacterial type II topoisomerase inhibitor.

Gepotidacin is a novel, first-in-class, triazaacenaphthylene antibacterial that inhibits bacterial DNA gyrase and topoisomerase IV via a unique mechanism and has demonstrated in vitro activity against gram-negative and gram-positive bacterias , including drug-resistant strains, and also targets pathogens associated with other conventional and biothreat infections. The MIC50 and MIC90 for gepotidacin against the 25 N. gonorrhoeae isolates tested are 0.12 and 0.25 μg/mL, respectively[1]. The gepotidacin MIC90s are as follows (in μg/mL): Streptococcus pyogenes, 0.25; Escherichia coli, 2; Moraxella catarrhalis, ≤0.06; Streptococcus pneumoniae, 0.25; Haemophilus influenzae, 1; Clostridium perfringens, 0.5; and Shigella spp., 1[2]. Gepotidacin hasin vitroactivity against causative pathogens of acute bacterial skin and skin structure infections (ABSSSIs)[3].

GSK2140944 MICs are 0.125 to 0.5 mg/L against the six MRSA isolates. ELF penetration ratios range from 1.1 to 1.4. Observed maximal decreases are 1.1 to 3.1 log10 CFU in neutropenic mice. The mean fAUC/MIC ratios required for stasis and 1-log-unit decreases are 59.3 ± 34.6 and 148.4 ± 83.3, respectively.

[1]. Farrell DJ, et al. In Vitro Activity of Gepotidacin (GSK2140944) against Neisseria gonorrhoeae. Antimicrob Agents Chemother. 2017 Feb 23;61(3). [2]. Biedenbach DJ, et al. In Vitro Activity of Gepotidacin, a Novel Triazaacenaphthylene Bacterial Topoisomerase Inhibitor, against a Broad Spectrum of Bacterial Pathogens. Antimicrob Agents Chemother. 2016 Jan 4;60(3):1918-23. [3]. O'Riordan W, et al. Efficacy, Safety, and Tolerability of Gepotidacin (GSK2140944) in the Treatment of Patients with Suspected or Confirmed Gram-Positive Acute Bacterial Skin and Skin Structure Infections. Antimicrob Agents Chemother. 2017 May 24;61(6). [4]. So W, et al. Pharmacodynamic Profile of GSK2140944 against Methicillin-Resistant Staphylococcus aureus in a Murine Lung Infection Model. Antimicrob Agents Chemother. 2015 Aug;59(8):4956-61.