Table 3

Activities of BC-3781 and comparator antimicrobial agents against bacterial pathogens causing predominantly ABSSSI and other infections

Species (no. tested) and antimicrobial agentMIC50 (μg/ml)MIC90 (μg/ml)Range (μg/ml)CLSI %S/%RaEUCAST %S/%Ra
S. aureus (5,527)
    BC-37810.120.120.015–>16
    Clindamycin≤0.25>2≤0.25–>282.0/17.881.4/18.0
    Daptomycin0.250.5≤0.06–2>99.9/−>99.9/<0.1
    Doxycycline0.120.25≤0.06–>897.9/0.495.3/3.1
    Erythromycin2>4≤0.25–>449.2/49.149.2/50.0
    Levofloxacin≤0.5>4≤0.5–>463.4/35.363.4/35.3
    Linezolid11≤0.12–4100.0/0.0100.0/0.0
    Oxacillin0.5>2≤0.25–>257.1/42.957.1/42.9
    Quinupristin-dalfopristin≤0.5≤0.5≤0.5–>499.9/0.199.9/0.1
    Tigecyclineb0.120.25≤0.03–0.5100.0/−100.0/0.0
    Trimethoprim-sulfamethoxazole≤0.5≤0.5≤0.5–>497.7/2.397.7/2.0
    Vancomycin110.25–2100.0/0.0100.0/0.0
MRSA (2,370)
    BC-37810.120.250.015–4
    Clindamycin≤0.25>2≤0.25–>263.5/36.463.1/36.5
    Daptomycin0.250.5≤0.06–299.9/−99.9/0.1
    Doxycycline0.121≤0.06–>896.2/0.893.0/5.4
    Erythromycin>4>4≤0.25–>415.0/84.115.0/84.6
    Levofloxacin>4>4≤0.5–>426.8/71.226.8/71.2
    Linezolid11≤0.12–2100.0/0.0100.0/0.0
    Oxacillin>2>2>20.0/100.00.0/100.0
    Quinupristin-dalfopristin≤0.5≤0.5≤0.5–>499.9/0.199.9/0.1
    Tigecyclineb0.120.25≤0.03–0.5100.0/−100.0/0.0
    Trimethoprim-sulfamethoxazole≤0.5≤0.5≤0.5–>495.8/4.295.8/3.8
    Vancomycin110.25–2100.0/0.0100.0/0.0
Beta-hemolytic Streptococcus spp. (763)
    BC-37810.030.03≤0.008–16
    Clindamycin≤0.25>2≤0.25–>287.3/12.687.4/12.6
    Daptomycin≤0.060.25≤0.06–0.5100.0/−100.0/0.0
    Doxycycline0.258≤0.06–>851.1/48.1
    Erythromycin≤0.25>4≤0.25–>476.4/22.776.4/22.7
    Levofloxacin≤0.51≤0.5–>499.2/0.495.8/0.8
    Linezolid110.5–2100.0/−100.0/0.0
    Penicillin≤0.030.06≤0.03–0.12100.0/−100.0/0.0
    Quinupristin-dalfopristin≤0.5≤0.5≤0.5–1100.0/0.0
    Tigecyclineb≤0.030.06≤0.03–0.25100.0/−100.0/0.0
    Trimethoprim-sulfamethoxazole≤0.5≤0.5≤0.5–>498.4/1.4
    Vancomycin0.250.5≤0.12–1100.0/−100.0/0.0
S. pyogenes, group A streptococci (267)
    BC-37810.030.03≤0.008–0.06
    Clindamycin≤0.25≤0.25≤0.25–>295.9/4.195.9/4.1
    Daptomycin≤0.06≤0.06≤0.06–0.25100.0/−100.0/0.0
    Doxycycline0.128≤0.06–>885.4/13.5
    Erythromycin≤0.25≤0.25≤0.25–>490.6/9.490.6/9.4
    Levofloxacin≤0.51≤0.5–>498.5/0.791.8/1.5
    Linezolid110.5–1100.0/−100.0/0.0
    Penicillin≤0.03≤0.03≤0.03–0.12100.0/−100.0/0.0
    Quinupristin-dalfopristin≤0.5≤0.5≤0.5100.0/0.0
    Tigecyclineb≤0.030.06≤0.03–0.12100.0/−100.0/0.0
    Trimethoprim-sulfamethoxazole≤0.5≤0.5≤0.5–>497.4/2.2
    Vancomycin0.250.5≤0.12–0.5100.0/−100.0/0.0
S. agalactiae, group B streptococci (334)
    BC-37810.030.03≤0.008–16
    Clindamycin≤0.25>2≤0.25–>278.4/21.378.7/21.3
    Daptomycin0.120.25≤0.06–0.5100.0/−100.0/0.0
    Doxycycline88≤0.06–>816.2/83.2
    Erythromycin≤0.25>4≤0.25–>463.8/34.463.8/34.4
    Levofloxacin≤0.51≤0.5–>499.7/0.397.6/0.3
    Linezolid110.5–1100.0/−100.0/0.0
    Penicillin≤0.030.06≤0.03–0.06100.0/−100.0/0.0
    Quinupristin-dalfopristin≤0.5≤0.5≤0.5–1100.0/0.0
    Tigecyclineb≤0.030.06≤0.03–0.25100.0/−100.0/0.0
    Trimethoprim-sulfamethoxazole≤0.5≤0.5≤0.5–>499.7/0.3
    Vancomycin0.50.50.25–1100.0/−100.0/0.0
Viridans group Streptococcus spp.c (245)
    BC-37810.120.5≤0.008–2
    Clindamycin≤0.25≤0.25≤0.25–>290.2/8.691.4/8.6
    Daptomycin0.250.5≤0.06–1100.0/−
    Doxycycline0.25>8≤0.06–>8
    Erythromycin≤0.25>4≤0.25–>451.8/46.1
    Linezolid110.25–2100.0/−
    Levofloxacin12≤0.5–>494.7/4.5
    Penicillin0.060.5≤0.03–>475.1/3.786.5/3.7
    Quinupristin-dalfopristin≤0.51≤0.5–1100.0/0.0
    Tigecyclineb≤0.030.06≤0.03–0.12100.0/−
    Trimethoprim-sulfamethoxazole≤0.52≤0.5–>4
    Vancomycin0.50.5≤0.12–1100.0/−100.0/0.0
E. faecium (536)
    BC-37810.1240.015–>16
    Ampicillin>8>8≤1–>85.8/94.25.8/94.2
    Daptomycin22≤0.06–4100.0/−
    Doxycycline4>8≤0.06–>855.6/32.8
    Erythromycin>4>4≤0.25–>43.4/87.1
    Levofloxacin>4>4≤0.5–>44.7/93.7
    Linezolid110.5–>898.7/0.999.1/0.9
    Quinupristin-dalfopristin≤0.52≤0.5–>488.2/4.788.2/0.2
    Tigecyclineb0.120.25≤0.03–>499.1/−99.1/0.2
    Vancomycin>16>160.25–>1643.3/56.343.3/56.7
  • a %S, percentage of susceptible organisms; %R, percentage of resistant organisms. Criteria were as published by the CLSI (2012) and EUCAST (2011) (25, 26).

  • b U.S. FDA breakpoints were applied (Tygacil label [27]).

  • c Includes the following species (isolate numbers): S. anginosus (22), S. bovis (9), S. canis (2), S. constellatus (6), S. gallolyticus (11), S. gordonii (5), S. intermedius (2), S. milleri (5), S. mitis (64), S. mutans (4), S. oralis (16), S. parasanguinis (7), S. salivarius (20), S. sanguinis (13), S. vestibularis (2), and unspecified viridans group streptococci (57).