Site-specific conjugation of native antibody

Area of Science:

• Bioconjugation Chemistry
• Antibody Engineering
• Pharmaceutical Sciences

Background:

• Non-specific conjugation methods (e.g., acylation, alkylation) yield heterogeneous antibody conjugates with potential drawbacks like reduced binding affinity.
• Site-specific conjugation produces homogenous antibody conjugates, crucial for consistent developability and clinical efficacy.
• Comparisons show site-specific methods offer improved plasma stability, dose-dependent reproducibility, binding efficiency, and tumor uptake for antibody conjugates.

Purpose of the Study:

• To review standard and practical site-specific bioconjugation methods for native antibodies.
• To highlight the advantages of site-specific over non-specific conjugation strategies.
• To discuss the clinical relevance and future of site-specific antibody conjugates.

Main Methods:

• Chemo-enzymatic approaches: transglutaminase (TGase)-mediated transamidation and glycan remodeling (GlyCLICK) in the Fc region.
• Chemical approaches: selective disulfide reduction (ThioBridge) and N-terminal amine modification.
• Review of site-specific antibody-drug conjugates (ADCs) currently in clinical trials.

Main Results:

• Site-specific methods yield homogenous antibody conjugates with enhanced functional properties.
• Chemo-enzymatic and chemical strategies provide practical routes for site-specific modification of native antibodies.
• Numerous site-specific ADCs are progressing through clinical trials, demonstrating the clinical utility of these approaches.

Conclusions:

• Site-specific bioconjugation is essential for developing well-defined, homogenous antibody conjugates with improved therapeutic potential.
• The reviewed methods offer practical solutions for creating advanced antibody therapeutics.
• Future perspectives indicate continued growth and innovation in site-specific antibody conjugate development for clinical applications.