Oncoinvent secures new patent expanding protection for Radspherin®

First patent from a new patent family granted in China, strengthening the long‑term intellectual property protection for the Company’s lead product candidate.

Oslo, Norway, 19 March 2026: Oncoinvent (OSE: ONCIN), a biotech company developing a receptor-independent alpha radiopharmaceutical to eradicate cancer cells in the abdominal cavity after surgery with a single, targeted dose, today announces that the China National Intellectual Property Administration (CNIPA) has granted a new patent for Radspherin®, the Company’s lead product candidate, marking the first approval worldwide within this patent family.

The newly granted patent covers a key technical development to optimize Radspherin’s® performance, specifically the size-controlled calcium carbonate microparticle technology. With this grant, patent protection for Radspherin® in China is expanded in scope and duration, with a term extending to 2041. This complements the existing composition‑of‑matter patent, which is valid until 2035 (2036 in some jurisdictions). Corresponding patent applications from the same patent family remain under review in several major jurisdictions worldwide.

“We are very pleased to obtain this additional patent in China for Radspherin®,” said Oystein Soug, Chief Executive Officer at Oncoinvent. “As we continue to advance clinical development, it is essential that our innovation is backed by a strong and durable global intellectual property position.”

About Oncoinvent

Oncoinvent is developing Radspherin®, a receptor-independent alpha radiation therapy that leverages the unique anatomy of the abdominal cavity to destroy residual micrometastases using a single, highly localized dose of alpha radiation. The initial clinical focus is treatment of ovarian and colorectal cancer patients after surgical removal of the primary tumor and visible metastases in the peritoneum, the thin membrane lining the abdominal cavity and covering the abdominal organs.

This radiopharmaceutical is designed to prevent or delay recurrence in the peritoneal cavity, keeping patients disease-free for longer than the current standard of care and thereby also impacting overall survival. It is broadly applicable to any cancer that spreads to the peritoneum, e.g. ovarian, colorectal, and gastric cancers. Radspherin stands out for its simplicity, excellent safety profile, and seamless integration into existing surgical workflows. Oncoinvent’s product is easy to use, avoids systemic delivery and significant toxicity. It is also differentiated in being simple to manufacture, scalable, and supply de-risked.

Data from two trials in ovarian (phase 1) and colorectal (phase 1/2a) cancers are highly promising, showing an excellent safety profile and meaningful signals of efficacy. Interim data from an ongoing, randomized, controlled phase 2 ovarian cancer trial is expected in 2026. With cost-effective manufacturing, blockbuster potential, active pharma partnership momentum, plus strong endorsements from leading experts, Oncoinvent is built for scale and commercial success, and is set to become the new standard for post-surgical cancer care. The Company was founded by the originators of Algeta and Xofigo (acquired by Bayer).