Radiopharmaceutical biotech Actithera successfully closed a $75.5 million Series A financing to advance its cancer drug pipeline targeting fibroblast activation protein (FAP). Despite operating as essentially a solo-founder startup prior to funding, the company leveraged industry experience and key opinion leader support to attract top-tier investors. Actithera aims to eliminate tumor-supportive connective tissue cells, improving immune and therapeutic access within tumors. This financing positions the company to enter clinical development amid growing investor interest in radioligand therapies, which offer precision targeting with attached radioisotopes. The company counts M Ventures, Hadean Ventures, Sofinnova Partners, and others among its backers.