AbClick Pro H: Scavenger-Free, Traceless Lys248 Conjugation Via O-Acyl Hydroxamate Chemistry for Homogeneous Antibody-Drug Conjugates (ADCs).

A traceless O-acyl hydroxamate Fc-binding peptide linker enables rapid, scavenger-free, and site-selective conjugation at Lys248 of human IgG1. The resulting homogeneous DAR2 antibody-drug conjugates (ADCs) retain antigen binding and internalization with payload-dependent stability and cytotoxicity. The linker's intrinsic leaving-group mechanism ensures clean FcBP release and broad payload compatibility. This robust, scalable traceless Lys248 conjugation chemistry underpins investigational new drug (IND)-approved and nonclinical ADC pipelines, offering a predictable platform for next-generation ADC design.