Selective estrogen receptor degraders (SERDs) and covalent antagonists (SERCAs): a patent review (2015-present)

The estrogen receptor (ER) is a clinically validated oncology target with a pivotal role in hormonally driven breast cancer, the most prevalent form of female cancer. Current treatments that directly modulate ER include antagonists (SERMs), such as tamoxifen, and degraders (SERDs), such as fulvestrant which is administered by intramuscular injection.This review covers patent applications that claim estrogen receptor degraders (SERDs) and covalent antagonists (SERCAs) between the period January 2015 to June 2021. A total of 114 patent applications from 23 different applicants are evaluated with stratification into acidic SERDs, basic SERDs, and SERCAs.The clinical success of fulvestrant in the treatment of ER+ breast cancer has spurred research over the last decade into the discovery and development of novel SERDs, with a particular focus on the discovery of orally bioavailable drugs. This has resulted in a diverse range of candidates entering clinical trials. Although some have faltered in development, a cohort of oral SERDs has generated encouraging efficacy and safety data that has allowed advancement into late stage clinical trials. Data from these trials is eagerly awaited, with these molecules having the potential to offer significant benefits in the treatment of ER+ breast cancer.