Table 1.

Affinity of ABT-806 and affinity-matured variants

Surface plasmon resonance (binding constants)a
EGFR 1-501EGFRvIII
ka (1/Ms)kd (1/s)KD (M)Fold increasebka (1/Ms)kd (1/s)KD (M)Fold increaseb
Cetuximab4.26E+051.71E–034.0E–093.46E+061.32E–033.8E–10
ABT-8063.53E+038.02E–032.3E–068.43E+047.93E–049.4E–09
AM13.26E+037.31E–042.2E–0710.17.61E+041.73E–042.3E–094.1
  • aEGFR: 6-point, 3-fold dilution series from 3 μmol/L to 12.35 nmol/L, fit to a 1:1 binding model using Biacore T100 Evaluation Software.

  • bThe Kd ratio of the affinity-matured variant relative to the parental ABT-806 (AM variant Kd/ABT-806 Kd).