TABLE 1

MIC distribution for meropenem alone and combined with vaborbactam at various concentrations against 315 Enterobacteriaceae strains producing serine carbapenemases

Antimicrobial agent(s)No. (cumulative %) of strains with indicated MIC (μg/ml)aMIC (μg/ml)
≤0.060.120.250.51248163264>6450%90%
Meropenem alone1 (0.3)6 (2.2)16 (7.3)43 (21.0)53 (37.8)82 (63.8)36 (75.2)24 (82.9)54 (100.0)16>64
Meropenem + vaborbactam at fixed concn (μg/ml) of:
 0.560 (19.0)51 (35.2)46 (49.8)31 (59.7)25 (67.6)16 (72.7)9 (75.6)8 (78.1)6 (80.0)17 (85.4)28 (94.3)18 (100.0)0.564
 1124 (39.4)47 (54.3)36 (65.7)16 (70.8)10 (74.0)10 (77.1)4 (78.4)2 (79.0)19 (85.1)17 (90.5)19 (96.5)11 (100.0)0.1232
 2182 (57.8)30 (67.3)16 (72.4)11 (75.9)7 (78.1)5 (79.7)14 (84.1)15 (88.9)15 (93.7)12 (97.5)3 (98.4)5 (100.0)≤0.0616
 4207 (65.7)22 (72.7)13 (76.8)9 (79.7)18 (85.4)15 (90.2)15 (94.9)5 (96.5)7 (98.7)1 (99.0)1 (99.4)2 (100.0)≤0.062
 8224 (71.1)20 (77.5)18 (83.2)21 (89.8)12 (93.7)9 (96.5)4 (97.8)0 (97.8)6 (99.7)0 (99.7)0 (99.7)1 (100.0)≤0.061
 16233 (74.0)21 (80.6)29 (89.8)17 (95.2)5 (96.8)4 (98.1)0 (98.1)1 (98.4)4 (99.7)0 (99.7)0 (99.7)1 (100.0)≤0.060.5
 32236 (74.9)30 (84.4)26 (92.7)13 (96.8)1 (97.1)3 (98.1)1 (98.4)0 (98.4)4 (99.7)0 (99.7)0 (99.7)1 (100.0)≤0.060.25
Vaborbactam alone315 (100.0)>64>64
  • a —, dilution not tested or no isolates displaying MIC values at this concentration.