TerraPower Isotopes announced on Mar. 18 that it will invest $450 million to build a manufacturing facility in Philadelphia, aiming to increase production capacity for the radioisotope actinium-225 by twenty times.
The move comes as demand for actinium-225, an alpha-emitting isotope used in next-generation radioligand therapies, has outpaced supply. The shortage has affected clinical trials, including a Phase 3 study by Bristol Myers Squibb’s RayzeBio that was paused due to limited availability of the isotope in 2024.
TerraPower, co-founded by Bill Gates, plans to establish its new cGMP-compliant production facility at the former Philadelphia Energy Solutions refinery site. The company expects to create 225 full-time jobs over the next three years at the 250,000-square-foot leased facility and aims to begin producing actinium-225 there in 2029. The Commonwealth of Pennsylvania is contributing $10 million toward the project.
The company evaluated more than 350 locations across the United States and visited 49 sites in eight metropolitan areas before selecting Philadelphia’s Bellwether District as its East Coast base. TerraPower has also secured supply agreements with companies such as Aktis Oncology, Clarity Pharmaceuticals, Point Biopharma (acquired by Eli Lilly for $1.4 billion in 2023), and PanTera, which supplies Bayer.
Historically, Oak Ridge National Laboratory supplied actinium-225 from thorium-229 left over from nuclear weapons programs dating back to the mid-twentieth century. As demand increased, other suppliers like BWXT Medical, Eckert & Ziegler, Ionetix, ITM, Niowave, NorthStar Medical Radioisotopes and Nusano entered the market.
With major pharmaceutical companies including AstraZeneca, Bristol Myers Squibb (BMS), Lilly and Novartis advancing radioisotope-based cancer therapies and expanding their pipelines involving actinium-225 since last year, industry observers expect continued growth in both research activity and demand for this key material.
