Oslo, Norway, 26 February 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 its second half 2025 results.

Oncoinvent's management team will give an online presentation to investors,
analysts and the press at 09:30 CET today (details below).

Highlights:

Radspherin[®]

  · Reported positive final data from Phase 1 Trial of Radspherin[®] to treat
ovarian cancer
  · Published Phase 1 trial results for Radspherin[®] in ovarian cancer in
Gynecologic Oncology
  · Presented final safety and efficacy results from the Phase 1/2a trial of
Radspherin[®] to treat colorectal cancer at the 15th PSOGI International
Congress on Peritoneal Surface Malignancies

Corporate

  · Completed merger with BerGenBio and successfully uplisted to Oslo Stock
Exchange
  · Raised NOK 130 million in equity
  · Appointed Dr Ramzi Amri as Chief Financial Officer

Post-period highlights

  · January 2026: Included four additional sites in Oncoinvent's Phase 2 trial
  · February 2026: Present positive 24-month follow-up data from Phase 1 ovarian
cancer trial of Radspherin[®] at 27th Congress of the European Society of
Gynecological Oncology (ESGO) 2026

Oystein Soug, CEO, commented: "The second half of 2025 marked another productive
period for Oncoinvent, with solid advances across our clinical programs together
with important corporate and financial milestones. During the period, we
progressed the Radspherin[®] Phase 2 trial in ovarian cancer, delivered
meaningful scientific updates in two cancer indications, completed significant
strategic transactions, and in the process strengthened the company's financial
foundation ahead of the planned Phase 2 interim readout."

Presentation:

We invite to a live webcast today at 09.30 CET. It will be possible to submit
questions during the presentation.

  · Date: Thursday, 26 February 2026
  · Time: 9:30am CET
  · Webcast link: https://qcnl.tv/p/l-V8RQZomSSettvFIGnxjg

A recording of the webcast will be made available on www.oncoinvent.com after
the live sending.

Reporting material:

  · Oncoinvent 2H 2025
report (https://mb.cision.com/Public/15728/4313178/b79ae34c93871998.pdf)
  · Oncoinvent 2H25
presentation (https://mb.cision.com/Public/15728/4313178/b034e378391f908e.pdf)

The reporting material are also available in the Investor Relations section of
the Company's website at www.oncoinvent.com.

***

For further information, please contact:

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

This information is considered to be inside information pursuant to the EU
Market Abuse Regulation and is subject to the disclosure requirements pursuant
to Section 5-12 the Norwegian Securities Trading Act. This stock exchange
announcement was published by Renate Birkeli, Director Investor Relations, on
behalf of the Company, at the time and date stated above in this announcement.

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).