TABLE 1.
Ki values (in nanomolar) of β-lactamase inhibition by xeruborbactam and comparator BLIs a
| Enzyme | Class | CARB | Xeruborbactam | Vaborbactam | Avibactam | Relebactam | Taniborbactam | Durlobactam |
|---|---|---|---|---|---|---|---|---|
| KPC-2 | A | + | 1.4 ± 0.2 | 56 ± 15 | 11 ± 3 | 40 ± 8 | 32 ± 0.009 | 1.7 ± 0.4 |
| CTX-M-14 | A | − | 0.29 ± 0.06 | 33 ± 13 | 0.41 ± 0.13 | 10 ± 3 | 1.2 ± 0.5 | 0.37 ± 0.16 |
| CTX-M-15 | A | − | 0.37 ± 0.01 | 30 ± 4 | 0.18 ± 0.08 | 24 ± 1 | 2.6 ± 0.1 | 0.21 ± 0.12 |
| SHV-12 | A | − | 0.74 ± 0.21 | 21 ± 4 | 0.24 ± 0.07 | 36 ± 6 | 0.15 ± 0.03 | 0.74 ± 0.21 |
| TEM-10 | A | − | 0.66 ± 0.23 | 140 ± 40 | 1.4 ± 0.4 | 48 ± 7 | 2.8 ± 0.8 | 0.99 ± 0.44 |
| P99 | C | − | 8.5 ± 2.4 | 35 ± 15 | 10 ± 2 | 14 ± 2 | 2.4 ± 0.5 | 0.17 ± 0.08 |
| PDC1 | C | − | 14 | ND | 56 | 78 | 22 | ND |
| OXA-48 | D | + | 0.22 ± 0.08 | 1.4 ± 0.5 × 104 | 36 ± 10 | 1.8 ± 0.1 × 103 | 6.1 ± 0.7 | 0.72 ± 0.27 |
| OXA-23 | D | + | 0.74 ± 0.28 | 6.6 ± 1.1 × 103 | 1.7 ± 0.4 × 103 | ND | >2 × 104 | 94 ± 32 |
| VIM-1 | B | + | 32 ± 14 | >1.6 × 105 | >1.6 × 105 | >1.6 × 105 | 31 ± 3 | >1.6 × 105 |
| NDM-1 | B | + | 7.5 ± 2.1 | >1.6 × 105 | >1.6 × 105 | >1.6 × 105 | 4.5 ± 1.3 | >1.6 × 105 |
| IMP-1 | B | + | 240 ± 30 | >1.6 × 105 | >1.6 × 105 | >1.6 × 105 | >2 × 104 | >1.6 × 105 |
| IMP-26 | B | + | 4.1 × 103 ± 103 | >1.6×105 | >1.6×105 | >1.6×105 | >2 × 104 | >2 × 104 |
| L1 | B | + | 1.4 × 103 | ND | ND | ND | 1.7 × 104 | ND |
a
Nitrocefin was used as a substrate for all the enzymes except NDM-1 and IMP-1; for these two enzymes, Ki was determined using imipenem. K i app values are used for class A, C, and B enzymes, and Ki values are used for class B enzymes. CARB, carbapenemase; ND, not determined.