The Japan Atomic Energy Agency (JAEA) is looking to expand the capabilities of the Joyo experimental fast reactor in Oarai, Ibaraki Prefecture, by incorporating the production of medical radioisotopes, specifically focusing on actinium-225 for cancer treatment purposes. This initiative seeks to develop a therapy where actinium-225, contained in a drug, is administered to patients to specifically locate and treat cancer cells within the body. The JAEA officials are optimistic about the potential of using a fast reactor like Joyo to manufacture actinium-225 for medical applications, a process that is relatively rare on a global scale.
In collaboration with the National Cancer Center Japan, the JAEA signed an agreement for joint research and development efforts on cancer therapy utilizing actinium-225. While therapeutic trials involving radiation therapy for cancer treatment are ongoing in various countries, the limited supply of actinium-225 worldwide restricts the number of patients that can be treated each year to around 3,000 individuals. The aspiration of the JAEA to produce this radioisotope by the conclusion of fiscal 2026 is driven by the critical need for expanding treatment options for cancer patients.
The Joyo experimental fast reactor, designed for advancing plutonium-fueled fast reactor technology, has been out of operation since 2007 due to equipment malfunctions. The JAEA plans to revive the reactor by approximately the middle of fiscal 2026 and is actively engaging in the necessary procedures to secure approval from authorities in Ibaraki Prefecture and the town of Oarai for reactivation.