Oak Ridge Partnership Helps Move Cancer Treatments Closer to Market

Through an innovative public-private partnership, Isotek employees supporting the Uranium-233 Disposition Project extract thorium-229, which is shipped to TerraPower to support cancer treatment research.

OAK RIDGE, Tenn. - One of the Oak Ridge Office of Environmental Management's (OREM) highest priority cleanup projects continues to advance efforts to develop and make available a promising form of next generation cancer treatment.

OREM and contractor Isotek are leading an effort to eliminate the nation's inventory of uranium-233 (U-233) from storage at Oak Ridge National Laboratory (ORNL).

U-233 presents risks and is costly to keep safe and secure. Originally created in the 1950s and 1960s for potential use in reactors, it proved to be an unviable fuel source.

OREM's project is converting that material into a form safe for shipment and disposal. Additionally, an agreement with TerraPower is allowing Isotek employees to extract thorium-229 (Th-229), an extremely rare isotope, from the material before it is processed and disposed of.

"It's important to extract Th-229 because that isotope only comes from U-233," said Sarah Schaefer, Isotek president and project manager. "Most of the world's supply of U-233 is stored at ORNL, so once this material is dispositioned, no more Th-229 will be available."

Scott Claunch, president of TerraPower Isotopes, speaks at an event in Oak Ridge celebrating growing partnerships that are helping provide rare medical isotopes to support next generation cancer treatment research.

Isotek extracts the Th-229 before it's shipped to TerraPower. Then, TerraPower uses that material to recover actinium-225 (Ac-225), a medical isotope behind a promising form of cancer treatment called targeted alpha therapy.

TerraPower Isotopes announced last week that it has achieved another major milestone.

The company now produces Ac-225 at commercial scale, providing sustained access to the global pharmaceutical community through weekly production runs. As a result, this material is now used in multiple drug developers' radiopharmaceuticals in human clinical trials across the globe.

"This scale-up of production capacity of TerraPower Isotopes' Actinium-225 opens a new chapter in the development of cancer treatment options, and I'm proud to be part of the journey," said Scott Claunch, president of TerraPower Isotopes. "We are proud to be the first company to provide Actinium-225 at this scale, transforming how the pharmaceutical industry approaches cancer treatment with targeted alpha therapies."

Thorium-229 is extracted from uranium-233 (U-233) before the U-233 is processed and downblended for shipment and disposal. TerraPower then uses that material to recover actinium-225, a medical isotope behind a promising form of cancer treatment called targeted alpha therapy.

In treatments, the Ac-225 is attached to a molecule to selectively target and deliver the alpha-emitting radionuclide to a cancer site to potentially treat diseases such as prostate, breast, colon and neuroendocrine cancers, melanoma, and lymphoma, destroying the cancerous tissue with minimal damage to nearby healthy cells.

"We feel an incredible amount of pride that the gram quantities of thorium Isotek has extracted is now fueling clinical trials in cancer patients," said Schaefer. "It is no longer something that will happen in the future. The time is now."

Once all Th-229 has been extracted from the U-233 material currently stored at ORNL over the next four years - an estimated 40 grams - 100 times more doses of next generation cancer treatments will be available annually than are currently available worldwide.

Global demand for Ac-225 is expected to increase as more treatments are developed, making the work performed by OREM and Isotek more vital and impactful.

-Contributor: Ben Williams