Inclusion Criteria:

   - Histologically or cytologically confirmed carcinoma of the breast

   - Locally advanced and/or metastatic disease

   - Deleterious or pathogenic germline BRCA 1 or BRCA 2 mutation

   - Prior chemotherapy: Cohort 1) PR or CR to prior platinum-containing regimen for
   metastatic disease with disease progression > 8 weeks following the last dose of
   platinum; or Cohort 2) > 2 prior chemotherapy regimens for metastatic disease and no
   prior platinum for metastatic disease

   - ECOG performance status ≤ 1

   - Have adequate organ function

Exclusion Criteria:

   - Prior enrollment into a clinical trial of a PARP inhibitor

   - CNS metastasis except adequately treated brain metastasis documented by baseline CT or
   MRI scan that has not progressed since previous scans and that does not require
   corticosteroids for management of CNS symptoms

   - Prior malignancy except for prior BRCA-associated cancer as long as there is no
   current evidence of the prior cancer, carcinoma in situ of the cervix or non-melanoma
   skin cancer, and a cancer diagnosed and definitively treated >5 years prior to study
   enrollment with no subsequent evidence of recurrence

   - Known to be HIV positive, active hepatitis C virus, or active hepatitis B virus

   - Known hypersensitivity to any of the components of talazoparib