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. This expansion would include the production of medical radioisotopes, specifically actinium-225, which holds promise as a cancer treatment drug.
JAEA envisions a therapy where actinium-225 is injected into a patient to target and eliminate cancer cells. The agency believes that utilizing a fast reactor for actinium-225 production is a unique approach with few global parallels. They aim to begin manufacturing the radioisotope by the end of fiscal year 2026.
In February 2023, JAEA and the National Cancer Center Japan signed a collaboration agreement to research and develop cancer therapy using actinium-225. While therapeutic trials are ongoing in various countries, the limited global supply of actinium-225 restricts treatment to approximately 3,000 patients annually.
The Joyo reactor, designed for developing plutonium-fueled fast reactors, commenced operation in 1977 but has been offline since 2007 due to equipment issues. JAEA plans to reactivate Joyo around the middle of fiscal year 2026 and is currently pursuing the necessary approvals from Ibaraki Prefecture and the town of Oarai.