F-star

F-star is a UK-based clinical-stage biopharmaceutical company pioneering bispecific antibodies for cancer immunotherapy. Founded in 2006 in Vienna and later headquartered at the Babraham Research Campus near Cambridge, UK, F-star developed its proprietary Modular Antibody Technology platform, which introduces additional antigen-binding sites into the constant region (Fcab) of an antibody to create tetravalent bispecifics. The company's pipeline focused on next-generation checkpoint inhibitors including FS118 (LAG-3/PD-L1) and FS222 (CD137/PD-L1). After a 2020 reverse merger with Spring Bank Pharmaceuticals took it public on NASDAQ under the ticker FSTX, F-star was acquired in March 2023 by invoX Pharma, a UK subsidiary of China's Sino Biopharmaceutical, for approximately $161 million and delisted.