Table 2.
MIC range and MIC50 of gepotidacin and ciprofloxacin for 252 clinical N. gonorrhoeae isolates and international reference strains divided into the different mutation patterns observed in the QRDRs of the gyrA and parC genes
| Mutation | Gepotidacin |
Ciprofloxacin |
||
|---|---|---|---|---|
| MIC range | MIC50 | MIC range | MIC50 | |
| gyrAa | ||||
| WT (n = 101) | 0.032–2 | 0.25 | <0.002–0.125 | 0.004 |
| S91F, D95G (n = 107) | 0.032–4b | 0.5 | 0.5 to >32 | >32 |
| S91F, D95A (n = 21) | 0.125–2 | 0.5 | 0.5 to >32 | 2 |
| S91F, D95N (n = 13) | 0.064–4c | 0.5 | 1 to >32 | >32 |
| S91F (n = 8) | 0.25–2 | 2 | 0.125–1 | 0.25 |
| S91F, D95Y (n = 1) | 4d | – | >32 | – |
| S91Y (n = 1) | 1 | – | 0.25 | – |
| parC | ||||
| WT (n = 118) | 0.032–2 | 0.5 | <0.002–4 | 0.004 |
| S87R (n = 75) | 0.032–2 | 0.5 | 2 to >32 | >32 |
| E91G (n = 21) | 0.125–1 | 0.5 | 1 to >32 | 4 |
| D86N (n = 20) | 0.5–4 | 2 | 1 to >32 | 8 |
| S87R, S88P (n = 6) | 0.064–0.5 | 0.5 | 8 to >32 | >32 |
| S87N, E91Q (n = 3) | 0.125–0.25 | – | 2–8 | – |
| S87N, E91K (n = 2) | 0.5 | – | 4–8 | |
| S87N (n = 2) | 0.5, 2 | – | 1 to >32 | – |
| S87I (n = 1) | 0.5 | – | 4 | – |
| S87W (n = 1) | 0.25 | – | 0.002 | – |
| E91K (n = 1) | 4 | – | >32 | – |
| E91Q (n = 1) | 0.5 | – | 1 | – |
| D86N, S88P (n = 1) | 4 | – | >32 | – |
MICs (mg/L) were determined by agar dilution for gepotidacin and Etest for ciprofloxacin.
a
Of the 151 isolates with any gyrA QRDR mutation, 133 (88.1%) also had a parC QRDR mutation.
b
Includes one isolate with a gepotidacin MIC of 4 mg/L, which also had the ParC D86N mutation.
c
Includes one isolate with a gepotidacin MIC of 4 mg/L, which also had the ParC D86N and S88P mutations.
d
Isolate also had the ParC E91K mutation.