This is an open-label, randomized, active comparator, multicenter, international Phase 3 study of NKTR-102 versus TPC in patients with metastatic breast cancer who have stable brain metastases and have been previously treated with an anthracycline, a taxane, and capecitabine in either the adjuvant or metastatic setting (prior anthracycline may be omitted if medically appropriate or contraindicated for the patient).~In Group A, NKTR-102 will be administered at a dose level of 145 mg/m2 on a q21d schedule as a 90-minute intravenous (IV) infusion on Day 1 of each treatment cycle. In Group B, TPC will be administered per standard of care. Patients randomized to TPC will receive single-agent IV chemotherapy, limited to choice of one of the following 7 agents: eribulin, ixabepilone, vinorelbine, gemcitabine, paclitaxel, docetaxel, or nab-paclitaxel.~This study will randomize approximately 220 patients using a 1:1 randomization ratio and stratification based on geographic region, tumor receptor status, and Eastern Cooperative Oncology Group (ECOG) status. At Screening, the Investigator must determine which TPC will be offered to the patient.~Data will be collected on subsequent anticancer therapies in both treatment groups from the time patients come off the study treatment until the time of primary data analysis for Overall Survival (OS).~An independent data monitoring committee (DMC) will assess interim safety and efficacy data and determine final number of death events needed to provide 80% conditional power based on the zone adaptive design.
This is an open-label, randomized, active comparator, multicenter, international Phase 3 study of NKTR-102 versus TPC in patients with metastatic breast cancer who have stable brain metastases and have been previously treated with an anthracycline, a taxane, and capecitabine in either the adjuvant or metastatic setting (prior anthracycline may be omitted if medically appropriate or contraindicated for the patient).