The FDA has approved elacestrant (Orserdu – Stemline), an oral estrogen receptor antagonist, for treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer in postmenopausal women or men who had disease progression following endocrine therapy. Elacestrant is the first oral selective estrogen receptor degrader (SERD) to be approved for treatment of breast cancer; the injectable SERD fulvestrant (Faslodex, and generics) was approved more than 20 years...