Antibody drug conjugates (ADCs): an expanding rational treatment paradigm in breast cancer

Abstract

Recent advances in bioengineering and manufacturing have catapulted Antibody–drug conjugates (ADCs) to broader clinical applications. ADCs take advantage of the exquisite specificity of monoclonal antibodies (mAb) to deliver a highly potent cytotoxic agent to a specifically targeted cell expressing a selected antigen. HER2-positive breast cancer has served as a testing ground for ADC development in solid tumors that over-express HER2/neu by linking trastuzumab to a payload agent. With the current advances, ADCs leverage the selective targeting of monoclonal antibodies to deliver highly potent agents which otherwise have a narrow therapeutic index. Ado-trastuzumab emtansine (T-DM1) was the first ADC approved for patients with HER2-postive metastatic breast cancer (MBC) and fam-trastuzumab deruxtecan-nxki (T-DXd) was recently approved as well. Sacituzumab govitecan-hziy (SG) was approved in 2020 for patients with triple negative breast cancer (TNBC). Studies focusing on utilizing ADCs in earlier stages of breast cancer in the neoadjuvant or adjuvant setting, and central nervous system (CNS) disease are in progress. New ADCs and bispecific antibodies (bAbs) are also in development.