Alpha radiation therapy uses a radioactive substance that gives off a type of high-energy radiation called an alpha-particle to kill cancer cells. The radioactive substance is injected into a vein, travels through the blood, and collects in certain tissues in the body, such as areas of bone with cancer. This type of radiation causes less damage to nearby healthy tissue. Alpha emitter radiation therapy is being studied in the treatment of multiple types of cancer.
Niowave is operating a closed-loop cycle to domestically produce high-purity Ac-225 and other alpha emitters from Ra-226 using a superconducting electron linear accelerator. The commercial-scale system will produce 10 Ci per week of Ac-225 from a nitrate-based solution of Ra-226. The electron beam impinges on a photon converter to irradiate the Ra-226, inducing a photon-neutron reaction to Ra-225, which decays to Ac-225. Ac-225 is eluted continuously from the target vessel then centrifugal contactors are used to harvest and purify Ac-225 through a separation cascade. Unlike other production methods, including proton linacs (spallation of Th-232) and proton cyclotrons (Ra-226 bombardment), Niowave’s method does not generate any Ac-227 contamination in the Ac-225 product. Niowave’s superconducting linacs can handle higher production output (>500 Ci per year using a 20 MeV, 210 kW beam) than any other method. Demonstration-scale production of 10 mCi batches of Ac-225 at Niowave’s HQ has begun and will be complete in April 2019. Niowave is in a unique position to quickly take the lead in manufacturing alpha-emitters for cancer therapy.