ESR1 and breast cancer: lidERA BC (NCT04961996) (Study Details A Study Evaluating the Efficacy and Safety of Adjuvant Giredestrant Compared With Physician’s Choice of Adjuvant Endocrine Monotherapy in Participants With Estrogen Receptor-Positive, HER2-Negative Early Breast Cancer lidERA Breast Cancer ClinicalTrials.gov, 2023)is a phase III, randomized, global, multicenter, open-label study evaluating adjuvant giredestrant versus physician’s choice endocrine therapy (PCET) in ER+/HER2-eBC.