Oslo, Norway, 8 December 2025 - Oncoinvent, a clinical stage, radiopharmaceutical company developing innovative treatments for solid cancers, today announced the publication of 12-month data from its Phase 1 study of patients with platinum-sensitive recurrent ovarian cancer and peritoneal carcinomatosis. The results from the first patients have been published in the respected peer-reviewed journal Gynecologic Oncology, under the title: "First experience with intraperitoneal 224Ra-labeled microparticles after cytoreductive surgery in patients with peritoneal recurrence of platinum-sensitive epithelial ovarian cancer."

"We are proud to announce that our article has been published in Gynecologic Oncology. This recognition underscores the importance of our research and validates our ongoing efforts. As our phase 2 study progresses in patients with peritoneal metastasis from ovarian cancer, we remain fully committed to advancing new treatment options to address this urgent medical need," said Kari Myren, Chief Medical Officer at Oncoinvent.

The primary objectives of the phase 1 study were to evaluate the safety and tolerability of the alpha emitting therapy using ²²⁴Ra-labeled microparticles (Radspherin®) and to determine the recommended dose for subsequent clinical development. Initial experiences indicate that all dose levels were well tolerated, no dose limiting toxicity was observed during dose escalation and the highest dose of 7 MBq was selected as the recommended dose for the expansion phase.  Alongside the now published  12-month data, Oncoinvent has also released topline 24-month follow-up data for the phase 1 study in ovarian cancer patients.

A randomized controlled phase 2 study is ongoing to evaluate the efficacy and safety of Radspherin® in patients with peritoneal metastasis from ovarian cancer. The primary aim is to compare progression-free survival (PFS) between two groups: those who receive Radspherin® following complete surgical resection after pre-operative chemotherapy, and those treated with pre-operative chemotherapy and surgery alone. Further details can be found at clinicaltrials.gov.