Radiopharmaceutical biotech Actithera closed a $75.5 million Series A round, despite operating as a single-person company during fundraising. The financing will support clinical development of fibroblast activation protein (FAP)-targeted radiopharmaceutical candidates aimed at enhancing cancer treatment efficacy. Actithera’s approach involves delivering radioisotopes precisely to tumor-supporting fibroblasts to dismantle tumor microenvironment barriers. The funding round attracted participation from multiple prominent venture investors and underpins growing interest in radiopharmaceuticals driven by recent commercial successes.