Sesen Bio, Inc., a late-stage clinical company, focuses on designing, engineering, developing, and commercializing targeted fusion protein therapeutics (TFPTs) for the treatment patients with cancer. The company's lead product candidates include Vicinium, a locally-administered targeted fusion protein that is in phase 3 clinical trials for the treatment of high-risk non-muscle invasive bladder cancer (NMIBC); and VB6-845d, a systemically-administered product candidate for use in the treatment of various types of EpCAM-positive solid tumors. It also develops Vicinium in combination with Durvalumab, which is in Phase I clinical trials for use in the treatment of high-risk NMIBC; and Vicinium in combination with AstraZeneca's checkpoint inhibitor for the treatment of squamous cell carcinoma of the head and neck. The company was formerly known as Eleven Biotherapeutics, Inc. and changed its name to Sesen Bio, Inc. in May 2018. Sesen Bio, Inc. was founded in 2008 and is headquartered in Cambridge, Massachusetts.