TABLE 3.

In vitro activities of PPI-0903M and comparator agents tested against anaerobes

Bacterium group or antimicrobial agent (no. of isolates tested)MIC (μg/ml)% of isolates by category
50%90%RangeSusceptibleResistant
Bacteroides fragilis (20)
    PPI-0903M32>324->32a
    Meropenem0.2510.12-2100.00.0
    Metronidazole120.5-2100.00.0
    Clindamycin4>161->1635.050.0
Clostridium difficile (10)
    PPI-0903M240.06-8
    Meropenem221-4100.00.0
    Metronidazole0.50.5≤0.12-1100.00.0
    Clindamycin480.5-1640.040.0
Clostridium spp. (16)b
    PPI-0903M0.061≤0.016-1
    Meropenem≤0.0160.5≤0.016-1100.00.0
    Metronidazole440.5-4100.00.0
    Clindamycin0.58≤0.12->1668.812.5
Other gram-positive anaerobes (14)c
    PPI-0903M0.060.120.03-0.12
    Meropenem0.120.12≤0.016-0.12100.00.0
    Metronidazole>32>321->327.192.9
    Clindamycin0.252≤0.12->1692.97.1
Prevotella spp. (16)d
    PPI-0903M8>320.03->16
    Meropenem0.120.120.03-0.25100.00.0
    Metronidazole281-1693.80.0
    Clindamycin≤0.12>16≤0.12->1662.537.5
  • a —, no breakpoints have been established by the CLSI/NCCLS (3, 12).

  • b Includes 12 C. perfringens strains, 3 C. septicum strains, and 1 Clostridium sp. strain.

  • c Includes two Proprionibacterium acnes strains, nine Proprionibacterium sp. strains, and three Peptostreptococcus sp. strains.

  • d Includes six Prevotella bivia strains, one P. intermedia strain, one P. melaninogenica strain, two P. oralis strains, and six Prevotella sp. strains.