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)

This is a Phase III, global, randomized, open-label, multicenter, study evaluating the efficacy and safety of adjuvant giredestrant compared with endocrine therapy of physician's choice in participants with medium- and high-risk Stage I-III histologically confirmed estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative early breast cancer.

In addition, an open-label exploratory substudy will explore the safety and efficacy of giredestrant in combination with abemaciclib in a subset of the primary study population.