U.S. Department of Energy (DOE) efforts to dispose of spent nuclear waste left over from the Cold War has turned into a boon for supplies of actinium-225 (Ac-225), a highly sought-after radioisotope for new cancer treatments.
Key players recently updated AuntMinnie.com about the initiative, a spin-off of sorts of the DOE’s Oak Ridge Office of Environmental Management (OREM) in Tennessee.
“It’s been really neat for us to not only have the beneficial reuse, where we’re offsetting the cost of the American taxpayer, but you’re actually seeing something pretty cool come out of it in nuclear medicine space,” explained OREM manager Jay Mullis.
Ac-225 decays from parent isotope thorium-229 (Th-229), and that’s what’s being extracted from the uranium-233 in Tennessee and sent to TerraPower’s facility in Everett, WA, explained Sarah Schafer of Isotek, the DOE’s contractor on the project. She said the source material is considered a thorium-229 “cow.”
TerraPower Isotopes expects to “milk” on the order of 2,000 millicuries of Actinium-225 per gram per year from the Th-229, said Scott Claunch, president of TerraPower Isotopes, a subsidiary of TerraPower.
“So, if you do that math, it’s about 90,000 millicuries per year that we would expect to be harvesting once our supply chain is at scale,” he said.
TerraPower recently shipped its first batch of Ac-225 through the project, and boasts more than 10 supply agreements with radiopharmaceutical developers in the U.S., Canada, Australia, and in Europe. Other isotope developers are are gaining access to Ac-225 through the International Atomic Energy Association, while the U.K. recently launched an effort similar to OREM’s.
Ultimately, the demand for Ac-225 is driven by the rapid development of new cancer treatments — including theranostic “pairs” used in imaging and therapy in breast cancer, for instance.
“Many of these next generation drugs can be trialed clinically in humans and hopefully some of them will be approved and we can fight cancer more effectively than we are today,” Claunch noted.