TABLE 1

In vitro activity of cefiderocol and comparators against Gram-negative bacilli (n = 4,239) isolated by 50 medical center laboratories in North America from 2014 to 2015

Family/genus/species (no. of isolates)Antimicrobial agentMIC (μg/ml)aMIC interpretationb
RangeMIC50MIC90% susceptible% intermediate% resistant
Enterobacteriaceae (3,007)Cefiderocol≤0.002–80.060.5
Cefepime≤0.06 to >64≤0.060.593.72.24.2
Ceftazidime-avibactam≤0.06 to >640.120.599.900.1
Ceftolozane-tazobactam≤0.06 to >640.25194.31.84.0
Ciprofloxacin≤0.12 to >8≤0.12>886.21.412.3
Colistin≤0.25 to >80.5>882.4017.6
Meropenem≤0.06 to >64≤0.06≤0.0699.00.10.9
Meropenem-nonsusceptible Enterobacteriaceae (30)Cefiderocol0.008–20.121
Cefepime≤0.06 to >6416>6410.023.366.7
Ceftazidime-avibactam0.12 to >641496.703.3
Ceftolozane-tazobactam1 to >6464>6413.36.780.0
Ciprofloxacin≤0.12 to >88>820.016.763.3
Colistin≤0.25 to >80.5>866.7033.3
Meropenem2 to >64864013.386.7
Klebsiella spp.c (1,010)Cefiderocol≤0.002–40.060.25
Cefepime≤0.06 to >64≤0.060.593.92.04.2
Ceftazidime-avibactam≤0.06–80.120.510000
Ceftolozane-tazobactam≤0.06 to >640.25196.80.62.6
Ciprofloxacin≤0.12 to >8≤0.120.592.90.86.3
Colistin≤0.25 to >80.5199.400.6
Meropenem≤0.06 to >64≤0.06≤0.0698.40.11.5
Klebsiella pneumoniae (765)Cefiderocol≤0.002–40.030.5
Cefepime≤0.06 to >64≤0.060.592.72.25.1
Ceftazidime-avibactam≤0.06–80.120.510000
Ceftolozane-tazobactam≤0.06 to >640.25196.30.82.9
Ciprofloxacin≤0.12 to >8≤0.12191.51.17.5
Colistin≤0.25 to >80.5199.400.7
Meropenem≤0.06 to >64≤0.06≤0.0698.00.11.8
Klebsiella oxytoca (245)Cefiderocol≤0.002–20.060.25
Cefepime≤0.06 to >64≤0.060.1297.61.21.2
Ceftazidime-avibactam≤0.06–20.120.2510000
Ceftolozane-tazobactam≤0.06–640.250.598.401.6
Ciprofloxacin≤0.12 to >8≤0.12≤0.1297.102.9
Colistin≤0.25 to >80.5199.600.4
Meropenem≤0.06–8≤0.06≤0.0699.600.4
Escherichia coli (740)Cefiderocol≤0.002–20.060.25
Cefepime≤0.06 to >64≤0.06888.81.89.5
Ceftazidime-avibactam≤0.06–20.120.2510000
Ceftolozane-tazobactam≤0.06 to >640.250.597.41.01.6
Ciprofloxacin≤0.12 to >8≤0.12>866.00.133.9
Colistin≤0.25 to >80.5199.700.3
Meropenem≤0.06–4≤0.06≤0.0699.900.1
Serratia spp.d (503)Cefiderocol≤0.002–80.060.25
Cefepime≤0.06 to >64≤0.060.2598.01.20.8
Ceftazidime-avibactam≤0.06–20.120.510000
Ceftolozane-tazobactam0.12 to >640.5197.21.41.4
Ciprofloxacin≤0.12 to >8≤0.12190.34.85.0
Colistin0.5 to >8>8>85.0095.0
Meropenem≤0.06–64≤0.060.1298.20.41.4
Serratia marcescens (472)Cefiderocol0.004–80.060.25
Cefepime≤0.06 to >64≤0.060.2597.91.30.9
Ceftazidime-avibactam≤0.06–20.120.510000
Ceftolozane-tazobactam0.12 to >640.5197.01.51.5
Ciprofloxacin≤0.12 to >8≤0.12289.65.15.3
Colistin0.5 to >8>8>85.1094.9
Meropenem≤0.06–64≤0.060.1298.10.41.5
Enterobacter spp.e (494)Cefiderocol0.004–40.251
Cefepime≤0.06 to >64≤0.06193.94.51.6
Ceftazidime-avibactam≤0.06–40.250.510000
Ceftolozane-tazobactam≤0.06–640.25881.86.311.9
Ciprofloxacin≤0.12 to >8≤0.120.2594.91.83.2
Colistin≤0.25 to >80.5291.308.7
Meropenem≤0.06–32≤0.060.1299.600.4
Enterobacter aerogenes (238)Cefiderocol0.004–40.120.5
Cefepime≤0.06–16≤0.060.597.12.50.4
Ceftazidime-avibactam≤0.06–40.250.510000
Ceftolozane-tazobactam≤0.06–160.25481.910.18.0
Ciprofloxacin≤0.12 to >8≤0.120.2597.50.42.1
Colistin≤0.25 to >80.5198.301.7
Meropenem≤0.06–8≤0.060.1299.600.4
Enterobacter cloacae (213)Cefiderocol0.008–40.251
Cefepime≤0.06 to >64≤0.06489.27.53.3
Ceftazidime-avibactam≤0.06–40.25110000
Ceftolozane-tazobactam≤0.06–640.5880.33.316.4
Ciprofloxacin≤0.12 to >8≤0.12192.53.34.2
Colistin≤0.25 to >80.5194.805.2
Meropenem≤0.06–32≤0.060.1299.500.5
Enterobacter asburiae (30)Cefiderocol≤0.06–0.50.251
Cefepime≤0.06–2≤0.060.2510000
Ceftazidime-avibactam0.12–160.250.510000
Ceftolozane-tazobactam≤0.12 to >80.25886.7013.3
Ciprofloxacin≤0.25 to >8≤0.120.593.306.7
Colistin≤0.06–0.25>8>813.3086.7
Meropenem≤0.06–0.5≤0.060.1210000
Citrobacter spp.f (260)Cefiderocol≤0.002–20.120.25
Cefepime≤0.06 to >64≤0.060.2597.71.50.8
Ceftazidime-avibactam≤0.06 to >640.120.2599.200.8
Ceftolozane-tazobactam≤0.06 to >640.25193.10.86.2
Ciprofloxacin≤0.12 to >8≤0.120.593.90.45.8
Colistin≤0.25–20.5110000
Meropenem≤0.06–8≤0.06≤0.0699.20.40.4
Citrobacter freundii (143)Cefiderocol≤0.002–10.060.25
Cefepime≤0.06 to >64≤0.06196.52.11.4
Ceftazidime-avibactam≤0.06 to >640.120.599.300.7
Ceftolozane-tazobactam≤0.06 to >640.25888.11.410.5
Ciprofloxacin≤0.12 to >8≤0.12191.60.77.7
Colistin≤0.25–20.5110000
Meropenem≤0.06–8≤0.06≤0.0698.60.70.7
Citrobacter koseri (99)Cefiderocol0.06–20.250.5
Cefepime≤0.06–0.25≤0.06≤0.0610000
Ceftazidime-avibactam≤0.06–0.50.120.1210000
Ceftolozane-tazobactam≤0.06–10.250.510000
Ciprofloxacin≤0.12 to >8≤0.12≤0.1296.004.0
Colistin≤0.25–1≤0.25110000
Meropenem≤0.06–0.12≤0.06≤0.0610000
Pseudomonas aeruginosa (765)Cefiderocol≤0.002–80.060.5
Cefepime≤0.06 to >6441685.58.16.4
Ceftazidime-avibactam≤0.06 to >642898.002.0
Ceftolozane-tazobactam≤0.06 to >640.5297.71.21.2
Ciprofloxacin≤0.12 to >80.25877.97.514.6
Colistin≤0.25–41299.50.50
Meropenem≤0.06 to >640.25880.36.013.7
Meropenem-nonsusceptible Pseudomonas aeruginosa (151)Cefiderocol≤0.002–40.060.5
Cefepime1 to >6483253.621.924.5
Ceftazidime-avibactam0.5 to >644890.709.3
Ceftolozane-tazobactam0.25 to >641490.14.65.3
Ciprofloxacin≤0.12 to >82>843.712.643.7
Colistin≤0.25–41199.30.70
Meropenem4 to >64816030.569.5
Acinetobacter baumannii (309)Cefiderocol≤0.002–80.121
Cefepime0.25 to >64166449.220.130.7
Ceftazidime-avibactam1 to >6416>64
Ceftolozane-tazobactam≤0.06 to >648>64
Ciprofloxacin≤0.12 to >8>8>834.30.365.4
Colistin≤0.25 to >80.5194.805.2
Meropenem≤0.06 to >648>6444.01.654.4
Meropenem-nonsusceptible Acinetobacter baumannii (173)Cefiderocol≤0.002–80.251
Cefepime4 to >6432>6416.831.851.5
Ceftazidime-avibactam4 to >6432>64
Ceftolozane-tazobactam0.5 to >6416>64
Ciprofloxacin0.25 to >8>8>81.7098.3
Colistin≤0.25 to >80.5291.308.7
Meropenem4 to >6464>6402.997.1
Stenotrophomonas maltophilia (152)Cefiderocol≤0.002–40.060.5
Cefepime1 to >6432>64
Ceftazidime-avibactam0.5 to >64864
Ceftolozane-tazobactam0.12 to >648>64
Ciprofloxacin0.25 to >82>8
Colistin≤0.25 to >82>8
Meropenem1 to >64>64>64
Burkholderia cepacia (6)Cefiderocol0.015–16
Cefepime16 to >64
Ceftazidime-avibactam4
Ceftolozane-tazobactam2–16
Ciprofloxacin0.5–8
Colistin>8
Meropenem2–883.316.70
  • a MIC50 and MIC90 calculated only for genus or species where >30 isolates were tested. Species of Enterobacteriaceae with <30 isolates were grouped with the overall genus data.

  • b Blank spaces mean that there are no CLSI, EUCAST, or FDA MIC breakpoints available for this agent.

  • c The 1,010 isolates of Klebsiella spp. were composed of 765 Klebsiella pneumoniae and 245 Klebsiella oxytoca isolates.

  • d The 503 isolates of Serratia spp. were composed of 472 Serratia marcescens, 22 Serratia liquefaciens, 4 Serratia ureilytica, 3 Serratia odorifera, 1 Serratia grimesii, and 1 Serratia rubidaea isolates.

  • e The 494 isolates of Enterobacter spp. were composed of 238 Enterobacter aerogenes, 213 Enterobacter cloacae, 30 Enterobacter asburiae, 10 Enterobacter kobei, 2 Enterobacter ludwigii, and 1 Enterobacter amnigenus isolates.

  • f The 260 isolates of Citrobacter spp. were composed of 143 Citrobacter freundii, 99 Citrobacter koseri, 10 Citrobacter braakii, 5 Citrobacter amalonaticus, 2 Citrobacter farmeri, and 1 Citrobacter sedlakii isolates.