TABLE 2.
Activity of contezolid (MRX-1) and comparator antimicrobial agents when tested against Gram-positive organisms from U.S. and European medical centers
| Organism/antimicrobial agent | MIC (mg/liter) |
Susceptibility (%) according toa
: |
||||
|---|---|---|---|---|---|---|
| CLSI |
EUCAST |
|||||
| MIC50 | MIC90 | S | R | S | R | |
| S. aureus (n = 606) | ||||||
| Contezolid | 0.5 | 1 | –c | – | – | – |
| Linezolid | 1 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Oxacillin | 0.5 | >4 | 65.7 | 34.3 | 65.7 | 34.3 |
| Doxycycline | 0.06 | 0.12 | 99.2 | 0.3 | 97.2 | 2.1 |
| Erythromycin | 0.5 | >8 | 50.3 | 45.9 | 52.5 | 47.4 |
| Clindamycin | ≤0.06 | >4 | 87.0 | 12.9 | 86.8 | 13.0 |
| Levofloxacin | 0.25 | >8 | 69.1 | 30.9 | 69.1 | 30.9 |
| TMP-SMXb | ≤0.12 | ≤0.12 | 99.2 | 0.8 | 99.2 | 0.5 |
| Vancomycin | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| MRSA (n = 208) | ||||||
| Contezolid | 0.5 | 1 | – | – | – | – |
| Linezolid | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Doxycycline | 0.06 | 0.25 | 98.6 | 0.5 | 96.2 | 2.9 |
| Erythromycin | >8 | >8 | 11.1 | 87.5 | 11.5 | 88.5 |
| Clindamycin | ≤0.06 | >4 | 66.8 | 33.2 | 66.8 | 33.2 |
| Levofloxacin | 8 | >8 | 20.7 | 79.3 | 20.7 | 79.3 |
| TMP-SMX | ≤0.12 | ≤0.12 | 98.1 | 1.9 | 98.1 | 1.0 |
| Vancomycin | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| CoNS (n = 100) | ||||||
| Contezolid | 0.25 | 0.5 | – | – | – | – |
| Linezolid | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Oxacillin | 4 | >4 | 35.0 | 65.0 | 35.0 | 65.0 |
| Doxycycline | 0.12 | 0.5 | 100.0 | 0.0 | 96.0 | 1.0 |
| Erythromycin | >8 | >8 | 43.0 | 56.0 | 44.0 | 56.0 |
| Clindamycin | ≤0.06 | >4 | 71.0 | 27.0 | 70.0 | 29.0 |
| Levofloxacin | 0.5 | >8 | 54.0 | 40.0 | 54.0 | 40.0 |
| TMP-SMX | ≤0.12 | >4 | 69.0 | 31.0 | 69.0 | 18.0 |
| Vancomycin | 1 | 2 | 100.0 | 0.0 | 100.0 | 0.0 |
| E. faecalis (n = 52) | ||||||
| Contezolid | 0.5 | 1 | – | – | – | – |
| Linezolid | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Levofloxacin | 1 | >8 | 75.0 | 25.0 | 75.0 | 25.0d |
| Vancomycin | 1 | 2 | 98.1 | 1.9 | 98.1 | 1.9 |
| E. faecium (n = 51) | ||||||
| Contezolid | 0.5 | 1 | – | – | – | – |
| Linezolid | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Levofloxacin | >8 | >8 | 5.9 | 92.2 | 7.8 | 92.2d |
| Vancomycin | >16 | >16 | 49.0 | 51.0 | 49.0 | 51.0 |
| Vancomycin resistant (n = 26) | ||||||
| Contezolid | 0.5 | 1 | – | – | – | – |
| Linezolid | 0.5 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Levofloxacin | >8 | >8 | 0.0 | 100.0 | 0.0 | 100.0d |
| Vancomycin | >16 | >16 | 0.0 | 100.0 | 0.0 | 100.0 |
| S. pneumoniae (n = 201) | ||||||
| Contezolid | 1 | 1 | – | – | – | – |
| Linezolid | 1 | 1 | 100.0 | – | 100.0 | 0.0 |
| Ceftriaxone | 0.03 | 1 | 90.0 | 2.5e | 90.0 | 0.5 |
| 97.5 | 0.5f | – | – | |||
| Erythromycin | 0.12 | >8 | 66.2 | 33.3 | 66.2 | 33.3 |
| Doxycycline | 0.12 | 8 | 76.1 | 23.4 | 77.1 | 22.4 |
| Clindamycin | ≤0.06 | >4 | 83.1 | 16.4 | 83.6 | 16.4 |
| Levofloxacin | 1 | 1 | 100.0 | 0.0 | 100.0 | 0.0 |
| Penicillin | ≤0.06 | 2 | 95.5 | 0.0g | 63.5 | 4.5f |
| TMP-SMX | 0.25 | >4 | 69.2 | 16.4 | 75.6 | 16.4 |
| Vancomycin | 0.25 | 0.25 | 100.0 | – | 100.0 | 0.0 |
| Beta-hemolytic streptococci (n = 102) | ||||||
| Contezolid | 1 | 1 | – | – | – | – |
| Linezolid | 1 | 1 | 100.0 | – | – | – |
| Ceftriaxone | 0.03 | 0.06 | 100.0 | – | 100.0 | 0.0 |
| Erythromycin | 0.12 | >8 | 72.5 | 27.5 | 72.5 | 27.5 |
| Doxycycline | 0.12 | 16 | – | – | 57.8 | 42.2 |
| Clindamycin | ≤0.06 | >4 | 82.4 | 17.6 | 82.4 | 17.6 |
| Levofloxacin | 0.5 | 2 | 98.0 | 0.0 | 88.2 | 2.0 |
| TMP-SMX | ≤0.12 | ≤0.12 | – | – | 99.0 | 1.0 |
| Vancomycin | 0.25 | 0.5 | 100.0 | – | 100.0 | 0.0 |
| Viridans group streptococci (n = 99) | ||||||
| Contezolid | 1 | 1 | – | – | – | – |
| Linezolid | 1 | 1 | 100.0 | – | – | – |
| Ceftriaxone | 0.12 | 0.5 | 94.9 | 4.0 | 93.9 | 6.1 |
| Erythromycin | 2 | >8 | 47.5 | 52.5 | – | – |
| Clindamycin | ≤0.06 | >4 | 84.8 | 13.1 | 86.9 | 13.1 |
| Levofloxacin | 1 | 2 | 93.9 | 4.0 | – | – |
| Vancomycin | 0.5 | 0.5 | 100.0 | – | 100.0 | 0.0 |
b
TMP-SMX, trimethoprim-sulfamethoxazole.
c
–, no breakpoint has been established.
d
Uncomplicated urinary tract infections only.
e
Using meningitis breakpoints.
f
Using nonmeningitis breakpoints.
g
Using parenteral, nonmeningitis breakpoints.