Actineer has successfully completed a closed-loop process to recycle Radium-226 and produce Actinium-225, the world’s most sought-after medical isotope in the fight against cancer. The joint venture between Canadian Nuclear Laboratories (CNL) and ITM Isotope Technologies Munich SE (ITM), established in October 2023 in Chalk River, Ontario, has reached a milestone long awaited by the global radiopharmaceutical community.
Actineer’s process is defined as “closed-loop”: Radium-226, a scarce and valuable material, is recovered after cyclotron irradiation, purified, and reintroduced into the production cycle. This minimizes waste and progressively increases irradiation capacity. Radium-226 is the essential precursor to Actinium-225 and is obtained primarily from decommissioned radioactive sources accumulated over decades by hospitals and industries worldwide. Global annual production of Ac-225 is currently estimated at just 1.7 Curies — enough to treat approximately 2,000 cancer patients. A figure far short of actual demand.
Actinium-225 decays with a ten-day half-life, emitting high-energy alpha particles. When paired with targeting molecules, it reaches cancer cells directly and destroys them with minimal damage to surrounding healthy tissue. This technique — Targeted Alpha Therapy (TAT) — is active in dozens of clinical trials targeting prostate cancer, breast cancer, and myeloid leukemia. Today’s bottleneck is not scientific: it is isotope availability. Actineer was created precisely to address this gap.
Actineer’s path toward commercial scale had already begun with the first production of Ac-225 in Canada through cyclotron irradiation of Ra-226 targets, in collaboration with the Sylvia Fedoruk Canadian Centre for Nuclear Innovation and Advanced Cyclotron Systems. That achievement earned the CNL team the CNIC 2024 Ecosystem Innovation Award. The closed-loop recycling of Ra-226 is the next step: it stabilizes the supply chain over the long term, removing dependence on external feedstock that is already scarce. CNL has built part of its Ra-226 inventory from decommissioned sources originating in countries such as Thailand and the Philippines, under the IAEA-promoted Global Radium-226 Management Initiative — a program that has completed 14 transfers from 14 different countries to date.
ITM brings to the joint venture the expertise it has developed as a global supplier of Lutetium-177 (Lu-177), the other major isotope in precision radiotherapy. The combination of German radiochemical know-how and Canadian nuclear infrastructure underpins Actineer’s plans to build a new Actinium Production Facility in Canada, designed to meet international demand in the years ahead. GMP-grade Ac-225 production was targeted for mid-2025, alongside the submission of a Drug Master File in the United States.
The market is moving quickly on multiple fronts: TerraPower Isotopes already produces Ac-225 at commercial scale on a weekly basis starting from Thorium-229, SpectronRx uses a proprietary accelerator-based method, and the U.S. Department of Energy has launched clinical trials with Ac-225 produced at Brookhaven and Los Alamos laboratories. Actineer’s distinguishing factor lies in its closed-loop approach to Ra-226: whoever solves the feedstock problem controls the value chain. If closed-loop recycling becomes the production standard, the scarcity of Actinium-225 could become a problem of the past — and with it, one of the main barriers to the global adoption of TAT.
