The Herceptin^® molecule
Herceptin^® is a recombinant humanised IgG1 kappa monoclonal antibody that selectively binds with high affinity to the extracellular domain of HER2. The molecule contains antigen-binding loops from within the variable region of an anti-HER2 murine monoclonal antibody (4D5), linked to human variable region framework residues and IgG1 constant domains¹.

Figure 1.2 Herceptin® binding to HER2

As the majority of the molecule is of human origin, Herceptin^® has low potential for immunogenicity and resultant production of anti-Herceptin^® antibodies.

REFERENCES
1. Cho HS et al. Nature 2003; 421: 756-760.