Application of immunocapture extraction coupled with LC-MS/MS methodology to the bioanalysis of a bispecific ADC

CBF 2.0 2025 -- A bispecific antibody-drug conjugate (ADC) combines the dual-targeting capability of a bispecific antibody with the potent killing payload of an ADC. By simultaneously binding two different tumor-associated antigens, it enhances tumor selectivity, improves internalization efficiency, and helps overcome tumor heterogeneity and drug resistance, thereby offering a promising strategy for precision cancer therapy. Immunocapture extraction coupled with LC-MS/MS offers a selective and sensitive strategy to quantify ADCs in biological matrices, which minimizes matrix interferences. Subsequent enzymatic cleavage allows for accurate measurement of the cytotoxic drug as a surrogate for ADC concentration. Compound A is a bispecific ADC. This study presents the development and application of an immunocapture LC-MS/MS method for the bioanalysis of a bispecific ADC, demonstrating its potential for supporting pharmacokinetic studies and therapeutic monitoring.