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Study confirms bioequivalency of cyclotron-produced Tc-99m


Sherbrooke, QC – Researchers at the Centre de research du Centre hospitalier universitaire de Sherbrooke (CRCHUS) have released the results of a clinical study demonstrating equivalency between cyclotron-produced technetium (Tc-99m) and that produced in a nuclear reactor. Based on the study’s findings, not only are the CRCHUS’s medical-imaging research positioned as leaders in this area, they are demonstrating that tomorrow’s supply of medical isotopes can be produced with a promising green technology.

“We are proud to present the preliminary results of this clinical study carried out in patients with thyroid disorders,” stated Éric E. Turcotte, MD, nuclear-medicine physician at the CHUS,researcher at the CRCHUS and professor in the Université de Sherbrooke’s Faculty of Medicine and Health Sciences. “We received Health Canada’s approval for this study in July 2014. The images for the first patient were taken in September 23, 2014; to date, a total of eleven patients have been injected with cyclotron-produced Tc-99m in the context of a medically indicated diagnostic testing. I want to thank them for having consented to take part in our study and having participated with such enthusiasm.”

Dr. Turcotte views the results as conclusive. “The images obtained with Tc-99m produced by our cyclotron are equivalent to those produced with Tc-99m from a nuclear reactor. They enabled us to make accurate diagnoses. As expected, none of the patients experienced side effects. We now intend to use this Tc-99m for more complex nuclear-medicine tests, in particular, assessing myocardial contractility and possibly ventilation studies in investigating pulmonary embolism.”

Tc-99m is used in more than 85% of nuclear-medicine diagnostic tests, such as cardiac imaging, bone scintigraphy to detect cancers, and many other tests to determine the functioning of various organs. The worldwide demand for Tc-99m is currently estimated at about 40 million doses per year, but scientists predict a 15% increase over the next ten years due to the aging of our populations. This means that the future supply of medical isotopes must be ensured.

Cyclotron-production of Tc-99m can offset these needs. The process does not produce nuclear waste, making it a promising green technology. It is also less expensive compared to the investment required to build a nuclear reactor.

“We have to bank on this technology, especially since the five main nuclear reactors producing close to 80% of the Tc-99m needed worldwide have been in service for more than 50 years (see below). Several are approaching the end of their service lives,” explained Dr. William D. Fraser, scientific director of the CRCHUS and professor at the Université de Sherbrooke’s Faculty of Medicine and Health Sciences. “The expected closure of some reactors in the near future will impact on the supply chain, and we must be ready to respond to the growing need for patient diagnostic tests.”

This clinical study represents an initial critical step towards marketing Tc-99m,” said Brigitte Guérin, researcher at the CRCHUS and professor in the Faculty of Medicine and Health Sciences at the Université de Sherbrooke. “We have demonstrated the process’s feasibility and confirmed the bioequivalency of Tc-99m produced in a high-performance cyclotron compared to that produced in a nuclear reactor. Our efforts are currently focused on implementing production on a larger scale and a system for distributing isotopes to regional and provincial hospitals in 2016.”