Nivolumab, Ipilimumab, and Bicalutamide in Human Epidermal Growth Factor (HER) 2 Negative Breast Cancer Patients

This is a phase II trial to assess the clinical efficacy and safety of nivolumab (anti-Programmed Death receptor-1, or anti-PD-1) combined with bicalutamide (Androgen Receptor (AR) inhibitor) and ipilimumab (anti-cytotoxic T-lymphocyte-associated protein 4, or anit-CTLA4) in patients with advanced breast cancer.

This study will include adult women with metastatic or locally advanced unresectable Human Epidermal Growth Factor (HER2)-negative breast cancer (by National Comprehensive Cancer Network (NCCN) criteria). Triple-negative breast cancer tumors will require confirmation of AR positivity at screening. Participants will have had no more than one line of previous chemotherapy in non-curative setting; subjects with metastatic progression within 1 year following completion of curative-intent chemotherapy are eligible if they have not received any additional lines of systemic therapy in the non-curative setting.

Women who meet all of the study inclusion criteria, none of the study exclusion criteria, and agree to participate will receive a combination of the following:

* Intravenous nivolumab 240mg, every 2 weeks until progression or unacceptable toxicity * Intravenous ipilimumab 1mg/kg, every 6 weeks until progression or unacceptable toxicity * Oral bicalutamide 150mg, daily until progression or unacceptable toxicity

Participants are to be treated for up to 24 months. Patients who have ongoing response will discontinue ipilimumab and nivolumab after 24 months, but at the discretion of the investigator may continue bicalutamide, and will continue assessments as per standard of care. Any patient who subsequently progresses will have the option to resume treatment upon disease progression.