- Adult women with locoregionally recurrent or metastatic disease not amenable to
- Confirmed diagnosis of ER positive breast cancer
- No prior systemic anti-cancer therapy for advanced ER+ disease.
- Postmenopausal women
- Measurable disease as per Response Evaluation Criterion in Solid Tumors [RECIST] or
- Eastern Cooperative Oncology Group [ECOG] 0-2
- Adequate organ and marrow function
- Patient must agree to provide tumor tissue
- Confirmed diagnosis of HER2 positive disease
- Patients with advanced, symptomatic, visceral spread that are at risk of life
threatening complication in the short term
- Known uncontrolled or symptomatic CNS metastases
- Prior (neo)adjuvant treatment with letrozole or anastrozole with DFI ? 12-months from
completion of treatment.
- Prior treatment with any CDK 4/6 inhibitor.