A Phase IIIb, Single-Arm, Open-Label Study Evaluating Adherence, Tolerability, and Patient Reported Outcomes (PRO) of Giredestrant in Patients With ER+/HER2- Early Breast Cancer Who Are Intolerant to Adjuvant Aromatase Inhibitor Therapy
The purpose of this study is to understand treatment adherence and patient-reported outcomes of switching to giredestrant due to prior aromatase inhibitor (AI) intolerance. Giredestrant will be administered as adjuvant endocrine therapy for participants with low-, medium-, and high-risk, Stage I-III, histologically confirmed, estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-), early breast cancer (eBC), as defined by the investigator. Participants will enroll if considered to be intolerant to a prior adjuvant AI therapy.
• Considered appropriate for treatment with endocrine therapy (ET)
• Histologically confirmed diagnosis of ER+/HER2-, Stage I-III (low-/medium-/high-risk) early breast cancer (eBC)
• Documented ER+ tumor according to American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP), defined as ≥1% of tumor cells stained positive
• Documented HER2- tumor according to ASCO/CAP
• Postmenopausal females at the time of signing the Informed Consent Form
• Documented use of a prior adjuvant aromatase inhibitor (AI) (i.e., anastrozole, exemestane, or letrozole) for a total of ≥6 months
• Documented use of an adjuvant AI (i.e., anastrozole, exemestane, or letrozole) for the consecutive ≥3 months immediately prior to consent
• Participant and investigator agree that current symptoms on AI are intolerable and warrant a switch in therapy to attempt sustained treatment
• Documented Grade 2 or 3 adverse events, per NCI CTCAE v6.0, determined by the investigator to be associated with AI therapy's intolerance
• Participant and investigator planning the first switch from an AI
• Has completed the following: (neo)adjuvant chemotherapy (if administered), definitive surgery of primary breast tumor(s) and/or axillary lymph nodes dissection (ALND) and/or sentinel lymph node biopsy (SLNB) and/or radiotherapy
• Eastern Cooperative Oncology Group Performance (ECOG) Performance Status 0 or 1