Anti PD-L1 Antibody + Anti CTLA-4 Antibody in Combination With Hormone Therapy in Patients With Hormone Receptor Positive HER2-negative Recurrent or Metastatic Breast Cancer

Phase II Study to Assess Efficacy, Safety & Immunological Biomarker of Anti PD-L1 Antibody + Anti CTLA-4 Antibody in Combination With Hormone Therapy in Patients With Hormone Receptor Positive HER2-negative Recurrent or Metastatic Breast Cancer

The aim of this study is to evaluate the safety and efficacy of anti PD-L1 antibody + anti CTLA-4 antibody in combination with hormone therapy in patients with hormone receptor positive HER2-negative recurrent or metastatic breast cancer.

Inclusion Criteria:

1. Patients aged >= 20 years at informed consent.
2. Patients who have provided written informed consent themselves.
3. Patients who have metastatic and/or advanced lesion
4. Documentation of ER-positive and/or PR-positive tumor (>=1% positive stained cells).
5. Patients with cancer confirmed to be HER2-negative.
6. Patients with confirmed menopause
7. Patients who have plans of 2nd hormone therapy.
8. Patients with a measurable lesion based on RECIST 1.1
9. Patients with ECOG PS of 0 to 1.
10. Patients without any severe disorder in the major organs.

Exclusion Criteria:

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Exclusion Criteria:

1. Active or prior documented autoimmune disease within the past 2 years.
2. Current or prior use of immunosuppressive medication within 28 days before the first dose of durvalumab or tremelimumab
3. Patients with central nervous system metastasis
4. Patients with life-threatening disease.
5. Patients with a history of treatment with anti-PD-1, anti-PD-L1, anti-PD-L2 or anti-CTLA-4 antibody drug.
6. Patients who have received live vaccination within 30 days before start of the investigational products.
7. Patients with a past medical history of pneumonia requiring steroid treatment or with a past medical history of interstitial pneumonia.
8. Patients considered ineligible for participation in this study by their attending physicians.