A Review of Current and Future Antibody Drug Conjugates in Breast Cancer

Antibody–drug conjugates (ADCs) are a novel class of anti-cancer agents that have changed the standard of care for patients with breast cancer. Their targeted approach delivers potent anti-cancer drugs to cancer cells bearing specific surface antigens, thereby maximizing anti-cancer effects and minimizing systemic toxicity. Currently, there are three ADCs available for use in breast cancer: trastuzumab emtansine for HER2 positive breast cancer (early stage and metastatic), trastuzumab deruxtecan for HER2 positive and HER2 low breast cancer (metastatic) and sacituzumab govitecan for triple negative and hormone receptor positive (HR +), HER2 negative breast cancer(metastatic). Trials have shown that these drugs have improved both progression free survival and overall survival in the metastatic setting, and trastuzumab emtansine has improved overall survival in early-stage breast cancer as well. The future of this class of compounds is very exciting. This field is rapidly evolving with new ADCs being investigated and clinical trials looking at the use of known ADCs in earlier stage disease.