Breast Cancer Clinical Trials

⁃ Cohort 1:

• Have histologically confirmed Stage I to III Estrogen Receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-) invasive breast carcinoma with Ki-67 at least 10%

• Be willing and able to provide pre- and on-treatment tumor samples.

• Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.

• Be able to swallow capsules or tablets.

• Be premenopausal women.

• If of childbearing potential must use 1 highly effective method of non-hormonal contraception while receiving study treatment and for the duration specified in protocol.

• Have adequate organ function.

⁃ Cohort 2:

• Have a diagnosis of ER+, HER2- early-stage, resected, invasive breast cancer without evidence of distant metastasis

• Have undergone definitive loco-regional therapy.

• Have received at least 4.5 years of any adjuvant endocrine therapy (ET), or at least 2 years of adjuvant ET with no additional ovarian suppression planned.

• Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.

• Be able to swallow capsules or tablets.

• Be premenopausal women

• If of childbearing potential must use 1 highly effective method of non-hormonal contraception while receiving study treatment and for the duration specified in protocol.

• Have adequate organ function.