molecules of the month

What is it? Elacestrant (Orserdu) is an oral, selective estrogen receptor modulator and degrader (SERM/SERD) that was recently approved for ER-positive, HER2-negative, estrogen receptor ɑ (ESR1)-mutated advanced or metastatic breast cancer (345 mg PO QD) based on progression-free survival (PFS) data from EMERALD (NCT03778931). As the first novel endocrine therapy approved in over 20 years and the first approved oral SERD, the drug marks an inflection point in the exciting and highly competitive pursuit of oral SERDs and a milestone for breast cancer treatment in general. The drug’s activity against difficult-to-treat ER-mutant tumors, thanks to a novel binding mode, allows it to improve survival among patients with ESR1-mutations detected in the ligand-binding domain via a circulating tumor DNA (ctDNA) companion…