Cetuximab interacts with the LR subdomain of EGFR.

Cetuximab, a chimeric mouse/human monoclonal antibody to EGFR used in the treatment of head, neck, and colorectal cancers. Cetuximab interacts with the LR2 domain sterically preventing the receptor from undergoing the necessary conformational change upon ligand binding to facilitate dimerization. .

Li S, Schmitz KR, Jeffrey PD, Wiltzius JJ, Kussie P, Ferguson KM. Structural basis for inhibition of the epidermal growth factor receptor by cetuximab. Cancer Cell. 2005;7(4):301-311. PMID: 15837620

1YY9 (PDB)

Herceptin binds to CR2 domain of HER2 (ErbB2)

Herceptin, a monoclonal antibody approved for treatment of breast cancers overexpressing HER2. Herceptin binds to the cysteine rich subdomain which may prevent ligand-independent dimerization similar to the autoinhibition between the CR1 and CR2 in the other members of ErbB. .

Choo HS, Mason K, Ramyar KX, Stanley AM, Gabelli SB, Denney DW, Leahy DJ. Structure of the extracellular region of HER2 alone and in complex with Herceptin Fab. Nature 2003;421(6924):451-4260. PMID: 12610629

1N8Z (PDB)