A Study of Multiple Immune and Disease Treatment Combinations in Participants With ER+HER2- Breast Cancer That Has Spread

For more information regarding Bristol-Myers Squibb Clinical Trial participation, please visit www.BMSStudyConnect.com

Inclusion Criteria:

Histological and cytological confirmation of adenocarcinoma of the breast
Documented HER2 negative and estrogen receptor (ER) positive status of primary or metastatic tumor tissue using the most recently assessed tumor specimen, according to the local laboratory parameters
ER negativity is defined as < 1% of tumor cells expressing hormonal receptors via IHC analysis
At least one measurable lesion, as per Response Evaluation Criteria in Solid Tumors version 1.1 [RECIST v1.1] that can be accurately assessed at baseline and is suitable for repeated assessment by computed tomography (CT) or magnetic resonance imaging (MRI)
Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
Women and Men must agree to follow specific methods of contraception, if applicable, while participating in the trial

Exclusion Criteria:

Allergy or hypersensitivity to any study drugs or their excipients
Any other sound medical, psychiatric and/or social reason as determined by the investigator
Active, known, or suspected autoimmune disease or immune-related diseases
History of unstable or deteriorating cardiac disease within the previous 12 months prior to screening
Prior therapy with anti-programmed death 1 (PD-1), anti-programmed death-ligand 1 (PD-L1) or anti-Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) class antibody
Any major surgery within 4 weeks of the first dose of study treatment

Other protocol-defined inclusion/exclusion criteria apply