Engineering an Enhanced EGFR Engager: Humanization of Cetuximab for Improved Developability

Area of Science:

• Oncology
• Immunology
• Biotechnology

Background:

• Epidermal growth factor receptor (EGFR) overexpression drives solid tumor development.
• Cetuximab, an EGFR inhibitor, is a chimeric antibody used since 2004 for cancer treatment.
• Mouse sequences in cetuximab can cause immunogenicity, and a glycosylation site may lead to hypersensitivity.

Purpose of the Study:

• To humanize cetuximab to reduce immunogenicity and improve biophysical properties.
• To engineer a more stable and less immunogenic EGFR inhibitor.
• To explore the potential of computationally guided protein engineering for therapeutic antibodies.

Main Methods:

• Humanization of cetuximab onto 11 new frameworks using framework grafting and sequence-/structure-guided methods.
• Removal of a variable heavy chain (VH) glycosylation site.
• Assessment of stability using dynamic light scattering and binding affinity using bio-layer interferometry.

Main Results:

• Humanization increased the overall 'humanness' of the antibody.
• The VH glycosylation site was successfully removed.
• Enhanced stability and minimal loss of binding affinity to EGFR were observed.
• Consistent improvements were noted across different humanization strategies.

Conclusions:

• Protein engineering can significantly improve first-generation biologics like cetuximab.
• Computational methods offer advantages for enhancing therapeutic antibody properties.
• Humanized cetuximab shows potential for reduced immunogenicity and improved stability in cancer therapy.