Table 1

Summary of ceftaroline-avibactam activity tested against 20,089 organisms from U.S. medical centers (2010-2011)

Organism (no. of isolates tested)aNo. of isolates (cumulative %) inhibited at MIC (μg/ml):MIC50 (μg/ml)MIC90 (μg/ml)
≤0.030.060.120.250.5124816>16
Enterobacteriaceae (4,908)2,028 (41.3)1,656 (75.0)656 (88.4)325 (95.0)172 (98.5)61 (99.8)7 (>99.9)3 (100.0)0.060.25
    Escherichia coli (1,375)1,024 (74.5)287 (95.3)49 (98.9)13 (99.9)2 (100.0)≤0.030.06
        Non-ESBL phenotype (1,217)961 (79.0)228 (97.7)24 (99.7)4 (100.0)≤0.030.06
        ESBL phenotype (158)63 (39.9)59 (77.2)25 (93.0)9 (98.7)2 (100.0)0.060.12
    Klebsiella spp. (1,964)619 (31.5)851 (74.8)311 (90.6)114 (96.4)44 (98.7)24 (99.8)2 (100.0)0.060.12
        Non-ESBL phenotype (1,689)590 (34.9)801 (82.4)232 (96.1)56 (99.4)10 (100.0)0.060.12
        ESBL phenotype (275)29 (10.5)50 (28.7)79 (57.5)58 (78.5)34 (90.9)23 (98.6)2 (100.0)0.120.5
        Meropenem nonsusceptible (72)3 (4.2)2 (6.9)11 (22.2)13 (40.3)20 (68.1)21 (95.8)2 (100.0)0.51
        Klebsiella pneumoniae (1,471)390 (26.5)674 (72.3)262 (90.1)84 (95.9)38 (98.4)21 (99.8)2 (100.0)0.060.12
        Klebsiella oxytoca (493)229 (46.5)177 (82.4)49 (92.3)30 (98.4)6 (99.6)2 (100.0)0.060.12
    Proteus mirabilis (230)39 (17.0)142 (78.7)41 (96.5)7 (99.6)1 (100.0)0.060.12
        Non-ESBL phenotype (222)38 (17.1)136 (78.4)41 (96.8)6 (99.5)1 (100.0)0.060.12
        ESBL phenotype (8)1 (12.5)6 (87.5)0 (87.5)1 (100.0)0.06
    Enterobacter cloacae (379)29 (7.7)101 (34.3)143 (72.0)70 (90.5)22 (96.3)11 (99.2)3 (100.0)0.120.25
        Ceftazidime susceptible (299)29 (9.7)100 (43.1)130 (86.6)35 (98.3)4 (99.7)1 (100.0)0.120.25
        Ceftazidime nonsusceptible (80)1 (1.3)13 (17.5)35 (61.3)18 (83.8)10 (96.3)3 (100.0)0.251
    Enterobacter aerogenes (143)66 (46.2)60 (88.1)10 (95.1)5 (98.6)2 (100.0)0.060.12
        Ceftazidime susceptible (123)66 (53.7)44 (89.4)8 (95.9)4 (99.2)1 (100.0)≤0.030.12
        Ceftazidime nonsusceptible (20)16 (80.0)2 (90.0)1 (95.0)1 (100.0)0.060.12
    Morganella morganii (308)165 (53.6)94 (84.1)30 (93.8)13 (98.1)6 (100.0)≤0.030.12
    Citrobacter koseri (115)57 (49.6)45 (88.7)8 (95.7)4 (99.1)0 (99.1)1 (100.0)0.060.12
    Citrobacter freundii (157)29 (18.5)75 (66.2)39 (91.1)8 (96.2)1 (96.8)4 (99.4)1 (100.0)0.060.12
    Serratia marcescens (237)1 (0.4)25 (11.0)91 (49.4)94 (89.0)22 (98.3)1 (98.7)3 (100.0)0.51
Pseudomonas aeruginosa (213)1 (0.5)10 (5.2)61 (33.8)63 (63.4)45 (84.5)18 (93.0)15 (100.0)416
Streptococcus pneumoniae (3,349)2,278 (68.0)287 (76.6)504 (91.6)247 (99.0)33 (100.0)≤0.030.12
    Penicillin MIC of ≥2 μg/ml (758)1 (0.1)32 (4.4)446 (63.2)246 (95.6)33 (100.0)0.120.25
    Penicillin MIC of ≥8 μg/ml (52)1 (1.9)5 (11.5)28 (65.4)18 (100.0)0.250.5
    Ceftriaxone nonsusceptible (372)1 (0.3)2 (0.8)134 (36.8)202 (91.1)33 (100.0)0.250.5
Haemophilus influenzae (1,679)1,675 (99.8)4 (100.0)≤0.03≤0.03
    β-Lactamase negative (1,220)1,218 (99.8)2 (100.0)≤0.03≤0.03
    β-Lactamase positive (459)457 (99.6)2 (100.0)≤0.03≤0.03
Haemophilus parainfluenzae (190)187 (98.4)2 (99.5)1 (100.0)≤0.03≤0.03
Moraxella catarrhalis (494)491 (99.4)2 (99.8)1 (100.0)≤0.03≤0.03
Staphylococcus aureus (4,315)2 (0.0)15 (0.4)363 (8.8)1,790 (50.3)1,495 (84.9)582 (98.4)68 (100.0)0.251
    MSSA (2,172)2 (0.1)15 (0.8)361 (17.4)1,723 (96.7)71 (100.0)0.250.25
    MRSA (2,143)2 (0.1)67 (3.2)1,424 (69.7)582 (96.8)68 (100.0)0.51
CoNS (1,131)63 (5.6)217 (24.8)204 (42.8)373 (75.8)246 (97.5)22 (99.5)6 (100.0)0.250.5
    MSCoNS (413)56 (13.6)203 (62.7)130 (94.2)24 (100.0)0.060.12
    MRCoNS (718)7 (1.0)14 (2.9)74 (13.2)349 (61.8)246 (96.1)22 (99.2)6 (100.0)0.250.5
    Staphylococcus epidermidis (240)15 (6.3)40 (22.9)37 (38.3)86 (74.2)59 (98.8)3 (100.0)0.250.5
    Staphylococcus haemolyticus (20)3 (15.0)9 (60.0)3 (75.0)2 (85.0)3 (100.0)0.252
    Staphylococcus hominis (27)2 (7.4)10 (44.4)11 (85.2)4 (100.0)0.250.5
β-Hemolytic streptococci (2,345)2,323 (99.1)21 (100.0)1 (100.0)≤0.03≤0.03
    Group A Streptococcus (913)909 (99.6)3 (99.9)1 (100.0)≤0.03≤0.03
    Group B Streptococcus (1,137)1,132 (99.6)5 (100.0)≤0.03≤0.03
    Group C Streptococcus (157)152 (96.8)5 (100.0)≤0.03≤0.03
Viridans group streptococci (1,051)801 (76.2)123 (87.9)58 (93.4)30 (96.3)27 (98.9)12 (100.0)≤0.030.12
    Streptococcus anginosus (90)81 (90.0)8 (98.9)0 (98.9)0 (98.9)1 (100.0)≤0.03≤0.03
Enterococcus faecalis (414)4 (1.0)11 (3.6)72 (21.0)212 (72.2)55 (85.5)49 (97.3)11 (100.0)28
  • a Abbreviations: MSSA, methicillin-susceptible S. aureus; CoNS, coagulase-negative staphylococci; MSCoNS, methicillin-susceptible coagulase-negative staphylococci; MRCoNS, methicillin-resistant coagulase-negative staphylococci.