The Japan Atomic Energy Agency (JAEA) has submitted a request to the Nuclear Regulation Authority to expand the goals of the Joyo experimental fast reactor in Oarai, Ibaraki Prefecture, to include medical radioisotope production. The agency has high hopes for the potential of actinium-225, a radioactive substance produced in the reactor, as a cancer treatment drug.
JAEA envisions a therapy where a drug containing actinium-225 is injected into a patient's body to target and destroy cancer cells. The use of a fast reactor for actinium-225 production is a unique approach with few parallels globally. The agency aims to begin manufacturing the radioisotope by the end of fiscal year 2026.
To further this goal, JAEA and the National Cancer Center Japan signed a collaboration agreement in February 2020 for research and development of actinium-225-based cancer therapy. While clinical trials are ongoing in various countries, the limited global supply of actinium-225 restricts treatment access to approximately 3,000 patients annually.
The Joyo reactor, originally designed for developing a plutonium-fueled fast reactor, has been offline since 2007 due to equipment issues. JAEA plans to reactivate the reactor around the middle of fiscal year 2026 and is currently seeking approvals from Ibaraki Prefecture and the town of Oarai.