Patent ID: 7985559

Claim:
A method of selecting a specific binding agent to an epidermal growth factor receptor (EGFr) polypeptide, wherein the specific binding agent binds to at least a portion of a panitumumab epitope on an EGFr polypeptide, comprising: a) contacting an EGFr polypeptide with an agent, wherein the EGFr polypeptide comprises the L2 domain of EGFr set forth in SEQ ID NO:3; b) determining the affinity of the agent for the EGFr polypeptide; c) contacting a mutant EGFr polypeptide with the agent, wherein the mutant EGFr polypeptide comprises at least one point mutation in at least one amino acid position selected from P349A, D355T, F412A, I438A, K443A, K465A, and I467A; d) determining the affinity of the agent for the mutant EGFr polypeptide; and e) selecting the agent if the affinity for the EGFr polypeptide is at least 2-fold greater than the affinity for the mutant EGFr polypeptide.