EMBER-4: This phase III study is measuring how well a new hormone therapy (imlunestrant) works compared to standard hormone therapy (tamoxifen, anastrozole, letrozole, or exemestane) in people with early breast cancer that is ER+ and HER2-A Randomized, Open-Label, Phase 3 Study of Adjuvant Imlunestrant vs Standard Adjuvant Endocrine Therapy in Patients Who Have Previously Received 2 to 5 Years of Adjuvant Endocrine Therapy for ER+, HER2- Early Breast Cancer With an Increased Risk of Recurrence

Exclusion

• Have any evidence of metastatic disease (including contralateral ALN) or inflammatory breast cancer at primary breast cancer diagnosis.
• Participants with more than a 6-month consecutive gap in therapy during the course of prior adjuvant ET.
• Participants who have completed or discontinued prior adjuvant ET >6 months prior to screening.
• Participants with a history of previous breast cancer are excluded, with the exception of ipsilateral DCIS treated by locoregional therapy alone ≥5 years ago.
• Pregnant, breastfeeding, or expecting to conceive or father children within the projected duration of the trial, starting with the screening visit through 180 days after the last dose of study intervention.
• Participant has previously received ET of any duration for breast cancer prevention (tamoxifen or AIs) or raloxifene.
• Participants with a history of any other cancer.
• Have serious preexisting medical conditions that, in the judgment of the investigator, would preclude participation in this study.