'Rarest Drug on Earth' Cancer Treatment Could Become More Common After Lab Creates Radioactive Isotope

A pair of Canadian labs claim to have produced "the rarest drug on earth," after unveiling a new batch of a scarce cancer fighting tool.

The "drug" in question is actually a rare radioactive isotope known as actinium-225. The isotope was produced at the TRIUMF particle accelerator at the University of British Columbia, and processed at the Canadian Nuclear Lab (CNL) Chalk River facility in Ontario.

TRIUMF announced their intention to produce the medicine last year, after experimental treatments suggested the isotope could be a powerful tool for doctors treating cancer. The treatments continue to be investigated, but a limited amount of mostly anecdotal evidence is said to suggest that treatments using the isotope may be very effective, especially in treating metastatic and late-stage cancers.

The unique properties of actinium-225 mean that when used in combination with cancer killing drugs as part of "targeted alpha therapy," the isotope can be specifically focused on cancer cells, while ignoring normal cells. Most effective cancer treatments remain unable to prevent healthy cells from being destroyed along with the cancer.

"While targeted alpha therapy using actinium-225 is one of the most promising new forms of cancer treatment, research has been limited due to global scarcity of the isotope," said CNL President Mark Lesinski in a press release. "Together, CNL and TRIUMF have now successfully demonstrated the viability of our production and separation processes, which could eventually enable hundreds of thousands of medical treatments every year across Canada and around the world. This achievement is a major leap forward in the availability of one of the rarest medical isotopes in the world."

The radioactive isotope may be a powerful tool in a promising form of targeted cancer treatment, but it has so far proved exceedingly difficult to produce in larger amounts. Getty

While the efficacy and safety of actinium-225 treatments are yet to be proven, the promising experimental data has only extended to a handful of patients per year, due to the extreme difficulty of producing the isotope.

"We have now successfully demonstrated a method of production that can be scaled up to produce meaningful quantities of actinium-225," claims Kathryn McCarthy, Vice President of Science and Technology at CNL. "There is still a long road to travel before these treatments are generally available to the public, but we've overcome a big hurdle that has prevented researchers from verifying the promising results that have been seen in early laboratory testing."

The majority of actinium-225 used on cancer patients so far has been produced at the U.S. Department of Energy Oak Ridge Laboratory in Tennessee, but the total amount produced worldwide is said to be enough for no more than a few hundred patients per year. CNF and TRIUMF say their method could mean a large increase in actinium-225 production, but the method needs to be perfected and is not expected to impact human use for another 5-10 years.