Immunomedics (NASDAQ: IMMU) May call option implied volatility is at 160, June is at 77; compared to its 52-week range of 52 to 172 into announcing lead investigational ADC, sacituzumab govitecan, induced "promising" objective responses as a single agent in heavily pre-treated patients with estrogen receptor-positive /human epidermal growth factor receptor 2-negative metastatic breast cancer. Sacituzumab govitecan generated a confirmed overall response rate of 31% in heavily pre-treated ER+/HER2- mBC patients. The six-month clinical benefit rate was 48%. Sacituzumab govitecan treatment was generally well tolerated, with no treatment-related deaths. Consistent with safety data obtained in metastatic TNBC, grade 3 or 4 toxicity with greater than 10% frequency included neutropenia and leukopenia. There was one case of grade 3/4 diarrhea and febrile neutropenia. Additional findings, including durability of responses and patient sub-group analyses will be presented in an oral session on June 3 at the ASCO meeting.