3. Histologically -confirmed metastatic or unresectable TNBC that has either progressed on or after an thracycline -based chemotherapy (or other approved standard of care therapy) or subject NANT TNBC Vaccine NantKwest, Inc. Clinical Trial Protocol: QUILT -3.067 Amendment 5 Confidential and Proprietary 10 has refused anthracycline -based chemotherapy, or other taxane - and platinum -based therapies. TNBC is defined as breast cancer that lacks estrogen receptor (ER) and progesterone receptor (PR) expression, and human epidermal growth factor receptor 2 (HER2) overexpression and/or amplification. 4.