TerraPower Isotopes Commits $450 Million to Build Philadelphia Actinium-225 Facility

TerraPower Isotopes committed $450 million to construct a 250,000-square-foot, cGMP-compliant actinium-225 production facility in Philadelphia's Bellwether District, positioning the Bill Gates co-founded company to become the world's top distributor of one of radiopharmaceuticals' most sought-after alpha emitters.

The facility, to be leased on the site of the former Philadelphia Energy Solutions refinery, is expected to begin producing Ac-225 in 2029. Combined with a concurrent capacity expansion at TPI's existing Everett, Washington site, the two projects are projected to deliver a 20-fold increase in TPI's total Ac-225 output. TPI expects to generate 225 full-time jobs in Philadelphia over the next three years, with approximately 500 construction jobs created during the build-out phase.

"This new facility is a testament to the demand for actinium-225 as part of the growing industry which is transforming how cancer is treated," said Scott Claunch, president of TerraPower Isotopes. "Our team is proud to be building a large-scale manufacturing facility in Philadelphia, which will play a pivotal role in expanding global access to this rare isotope."

The site selection came after TPI evaluated more than 350 U.S. locations and visited 49 sites across eight metropolitan areas. Ac-225's half-life of approximately 10 days drove the logic behind an East Coast presence: proximity to patients and treatment centers is a material constraint in radioisotope logistics, and the Bellwether District puts TPI inside one of the country's densest life sciences corridors.

The Department of Energy Isotope Program has identified Ac-225 as a critical isotope due to high demand and limited availability. The radioisotope's alpha decay path makes it a prime candidate for targeted alpha therapy, and multiple Ac-225-based cancer treatment programs are currently in human clinical trials. The isotope is central to radiopharmaceutical pipelines at AstraZeneca, Bristol Myers Squibb, Eli Lilly, and Novartis.

TPI has disclosed Ac-225 supply agreements with Aktis Oncology, Clarity Pharmaceuticals, and Point Biopharma, the latter of which Eli Lilly acquired for $1.4 billion in 2023. The company also struck a deal with PanTera, a European firm that supplies Ac-225 to Bayer.

Pennsylvania backed the project with $10 million in state support, structured as a $3 million Pennsylvania First grant and $7 million through the Pennsylvania Strategic Investments to Enhance Sites program. The Bellwether District location qualifies the facility for Keystone Opportunity Zone tax benefits through 2043. Governor Josh Shapiro's office announced the investment as part of a broader economic development push that the administration says has attracted more than $40.4 billion in private sector investment and over 22,400 new jobs since taking office.

Philadelphia Mayor Cherelle L. Parker called the project a "major win for Philadelphia" that will strengthen the city's manufacturing and life sciences sectors.

TerraPower president and CEO Chris Levesque framed the Philadelphia plant in terms of global supply constraints: "This new facility will help us increase the global supply of actinium-225 and increase access for researchers and drug developers who are advancing new cancer treatments."

Having initially built its Ac-225 operations from Washington State, TPI's dual-site strategy represents the most significant domestic capacity expansion for this isotope announced to date, at a moment when pharmaceutical demand is outpacing available supply.