Table I.
Binding Kinetics of ABP 980, Trastuzumab (EU) and Trastuzumab (US) to Recombinant HER2
| Sample | ka (M−1 s−1) × 105 | kd (s−1) × 10−5 | Kd (pM) |
|---|---|---|---|
| Trastuzumab (EU) Lot #1 | 6.33 | 5.77 | 91.6 |
| Trastuzumab (EU) Lot #2 | 6.99 | 4.41 | 63.0 |
| Trastuzumab (EU) Lot #3 | 6.67 | 4.64 | 69.0 |
| ABP 980 Lot #1 | 6.64 | 4.98 | 75.3 |
| ABP 980 Lot #2 | 6.61 | 5.16 | 78.7 |
| ABP 980 Lot #3 | 6.54 | 4.91 | 74.9 |
| ABP 980 Lot #4 | 6.65 | 5.13 | 76.7 |
| Trastuzumab (US) Lot #1 | 6.67 | 5.34 | 79.5 |
| Trastuzumab (US) Lot #2 | 7.30 | 4.90 | 67.1 |
| Trastuzumab (US) Lot #3 | 7.24 | 5.37 | 74.6 |
ka association rate constant, kd dissociation rate constant, Kd dissociation equilibrium binding constant, recombinant HER2 human epidermal growth factor receptor 2 extracellular domain, recombinantly expressed, trastuzumab (EU) EU authorized trastuzumab, trastuzumab (US) FDA licensed trastuzumab, s seconds, M molar