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."

For further information, please contact:

Oystein Soug, Chief Executive Officer
Email: IR@oncoinvent.com (soug@oncoinvent.com)

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).