A clinical-stage biotechnology company focused on developing targeted biopharmaceuticals for the treatment of cancer, neurodegenerative and autoimmune diseases through inhibition of Semaphorin 4D (SEMA4D). The company is developing product candidates for specific cancer indications, particularly head and neck squamous cell carcinoma, pancreatic cancer, and neurodegenerative diseases such as Huntington's disease. The company is based in Delaware.