TABLE 1.

Activities of doripenem and comparator agentsa

Organism (nb) and antimicrobial agentMIC50MIC90Geometric mean MICRange%S%I%R
B. fragilis (81)
    Doripenem (116)c0.510.50.25-169631
    Ertapenem0.250.50.30.12-410000
    Imipenem0.250.50.20.06-210000
    Meropenem0.120.50.20.12-89730
    Ceftriaxone32>3225.78->32154837
    Levofloxacin221.50.50-89154
B. ovatus (20)
    Doripenem (27)0.510.40.12-210000
    Ertapenem0.510.50.12-210000
    Imipenem0.250.50.20.06-0.5010000
    Meropenem0.250.50.20.03-0.5010000
    Ceftriaxone32>32258->32205030
    Levofloxacin8167.54-1602575
B. thetaiotaomicron (42)
    Doripenem (44)0.510.60.12-210000
    Ertapenem0.520.60.06-210000
    Imipenem0.510.40.03-110000
    Meropenem0.250.50.30.06-110000
    Ceftriaxone32>3231.116->3225840
    Levofloxacin886.31->3222969
Other B. fragilis grp. species (23)
    Doripenem (39)0.520.60.12-169802
    Ertapenem0.520.60.12-210000
    Imipenem0.510.40.03-110000
    Meropenem0.250.50.30.06-110000
    Ceftriaxone32>3230.316->3245343
    Levofloxacin2163.91-32521335
Bilophila wadsworthia (21)
    Doripenem0.120.120.10.03-0.1210000
    Ertapenem0.120.120.10.03-0.1210000
    Imipenem0.120.250.10.06-0.2510000
    Meropenem0.0620.120.10.03-0.1210000
    Ceftriaxone>32>3213.40.03->32104743
    Levofloxacin141.10.25-168695
Fusobacterium species (15)
    Doripenem0.03110.10.03-110000
    Ertapenem0.031100.03->329307
    Imipenem0.1210.10.03-210000
    Meropenem0.0310.1200.03-0.5010000
    Ceftriaxone0.5320.60.06->328767
    Levofloxacin110.80.25-110000
Porphyromonas species (20)
    Doripenem0.0310.50.10.03-410000
    Ertapenem0.0310.50.10.03-329505
    Imipenem0.0310.120.10.03-110000
    Meropenem0.0310.50.10.03-89550
    Ceftriaxone0.1210.20.03->329505
    Levofloxacin0.2510.40.06-210000
Prevotella oris/buccae (10)
    Doripenem0.120.50.20.03-0.5010000
    Ertapenem0.120.250.20.06-0.5010000
    Imipenem0.0620.250.10.03-0.5010000
    Meropenem0.120.250.10.03-0.2510000
    Ceftriaxone8>323.30.50->32502030
    Levofloxacin111.10.50-490100
Prevotella bivia and disiens (15)
    Doripenem0.120.50.10.03-410000
    Ertapenem0.250.50.20.03-110000
    Imipenem0.0620.250.10.03-210000
    Meropenem0.120.50.10.03-210000
    Ceftriaxone2321.90.12->328767
    Levofloxacin181.40.25-873720
Prevotella intermedia/nigrescens (10)
    Doripenem0.0310.06200.03-0.0610000
    Ertapenem0.0310.06200.03-0.0610000
    Imipenem0.0310.03100.03-0.0310000
    Meropenem0.0620.0620.10.03-0.0610000
    Ceftriaxone0.1240.30.03-810000
    Levofloxacin0.50.50.50.50-0.5010000
Other Prevotella species (22)
    Doripenem0.0620.120.10.03-0.2510000
    Ertapenem0.0620.250.10.03-0.2510000
    Imipenem0.0310.06200.03-0.1210000
    Meropenem0.0620.250.10.03-0.2510000
    Ceftriaxone0.25160.40.06->329505
    Levofloxacin110.90.50-110000
Sutterella wadsworthensis (12)
    Doripenem482.30.06-3273189
    Ertapenem0.510.30.03-110000
    Imipenem141.20.03-169109
    Meropenem441.10.03->329208
    Ceftriaxone>32>323.20.25->3225075
    Levofloxacin0.520.70.25-210000
Clostridium species (25)
    Doripenem120.50.03-410000
    Ertapenem280.80.03-884160
    Imipenem280.90.03-880200
    Meropenem120.50.03-410000
    Ceftriaxone8325.30.25->3272244
    Levofloxacin43240.25-32282844
Anaerobic gram-positive cocci (18)
    Doripenem0.0310.1200.03-0.2510000
    Ertapenem0.0310.250.10.03-0.2510000
    Imipenem0.0620.06200.03-0.1210000
    Meropenem0.0310.1200.03-0.1210000
    Ceftriaxone0.2540.40.12-410000
    Levofloxacin0.520.50.25-89505
Nonsporing gram-positive rods (30)
    Doripenem0.120.250.20.03-89730
    Ertapenem0.120.50.20.03-169703
    Imipenem0.120.250.10.03-110000
    Meropenem0.0620.250.10.03-89730
    Ceftriaxone0.250.50.20.06-1610000
    Levofloxacin281.70.25-3280713
Total (364)
    Doripenem (424)0.2510.30.03-329811
    Ertapenem0.2510.20.03->329811
    Imipenem0.1210.20.03-169820
    Meropenem0.120.50.20.03->329910
    Ceftriaxone32>3230.03->32472924
    Levofloxacin181.70.06->32691120
  • a %S, %I, and %R, percentage of isolates susceptible, intermediate, or resistant, respectively; grp., group. Susceptible (intermediate) breakpoints used were as follows: for ertapenem, imipenem, and meropenem, 4 (8) μg/ml; and for ceftriaxone, 16 (32) μg/ml. Doripenem does not have a CLSI-approved breakpoint, and a tentative breakpoint of 4 (8) μg/ml was used to facilitate comparison with the other carbapenems. A tentative breakpoint of 2 (4) μg/ml was used for levofloxacin, which also does not have a CLSI-approved breakpoint.

  • b No. of isolates.

  • c No. of isolates tested with doripenem.