Morris Plains-based biopharmaceutical company, Immunomedics’ lead investigational antibody-drug conjugate, sacituzumab govitecan, has received Breakthrough Therapy Designation from the FDA for the treatment of patients with triple-negative breast cancer (TNBC) who have failed at least 2 prior therapies for metastatic disease. TNBC is a serious disease, with an annual incidence estimated to be about 40,000 people, 20,000 for metastatic TNBC, in the United States. As the name implies, TNBC does not express estrogen, progesterone or the HER2 receptor, and is, therefore, insensitive to most of the available targeted therapies for breast cancer treatment, including HER2-directed therapy (such as trastuzumab), and endocrine therapies (such as tamoxifen or the aromatase inhibitors). The median overall survival is 6-13 months. There is currently no single standard chemotherapy to treat patients with relapsed/refractory metastatic TNBC. Rapid relapse, with visceral and brain metastases, is very common.