- Adult women and men at least 18 years of age and willing and able to provide informed
- Has advanced TNBC:
- TNBC is defined as staining by immunohistochemistry (IHC) estrogen receptor (ER) and progesterone receptor (PgR), and 0 or 1+ by IHC for human
epidermal growth factor receptor 2 (HER2) or negative for gene amplification (average
HER2 copy number
- Advanced disease is defined as locally advanced or metastatic disease not amenable to
curative intent surgery or radiotherapy.
- Has diagnostic-positive status as determined by a central diagnostic testing
- Received 0 or 1 prior line of systemic therapy in the advanced disease setting.
- Patients who received 1 prior line of therapy for locally advanced or metastatic TNBC
must have objective disease progression as assessed by the investigator.
- Has measurable and/or disease that is not measurable but is evaluable using RECIST 1.1
(eg, bone metastases, pathologic lymph nodes, or skin lesions).
- Patients with nonmeasurable and nonevaluable TNBC (eg, malignant effusions or bone
marrow as the only manifestations of disease) are not eligible for enrollment.
- Patients with metastatic disease limited to the bone must have disease adequately
visualized by computed tomography (CT) with bone windows, magnetic resonance imaging
(MRI), or x-ray.
- Has an Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1 at
screening and a life expectancy of at least 3 months from randomization.
- Received a taxane regimen ? 28 days in duration in the advanced disease setting.
- Prior taxane therapy for neoadjuvant and/or adjuvant disease is permitted.
- A single dose of a taxane given as part of an every-3-weeks regimen is permitted.
- Two doses of a taxane given as part of a once-weekly regimen is permitted.
- Had a disease-free interval of ? 12 months from the last dose of taxane when used as
part of adjuvant therapy for patients who did not receive prior therapy for locally
advanced or metastatic breast cancer.
- Has history of or known central nervous system (CNS) metastasis or active
leptomeningeal disease; brain imaging is required for all patients during screening.
- Received any anticancer agent (commercially available or investigational) within 14
days before randomization.
- Received treatment with any of the following medications within 14 days before
- Estrogens, including hormone replacement therapy
- Androgens (eg, testosterone, dehydroepiandrosterone)
- Systemic radionuclides (eg, samarium, strontium)
- Had major surgery within 4 weeks before randomization.
- Has a history of another invasive cancer within 3 years before randomization, with the
exception of fully treated cancers with a remote probability of recurrence.
- Has a history of a seizure condition or any condition that may predispose to seizure
(eg, prior cortical stroke or significant brain trauma).
- Has known hypersensitivity to any of the enzalutamide/placebo capsule components.
- Had a hypersensitivity reaction to Cremophor EL (polyoxyethylated castor oil) or a
drug formulated in Cremophor EL, such as paclitaxel, unless successfully treated and
rechallenged with appropriate premedications.