Grant: Alternative Radiopharmaceuticals for Medical Imaging

Technetium-99m (Tc99m) is the most commonly used isotope in nuclear medicine clinics across the country. This isotope is currently produced by a device called a generator, which is made from a parent radioactive compound called molybdenum-99 (Mo-99). Due to the widespread availability of technetium generators available from production of Mo-99 from nuclear reactors for many years, the fact that Tc radioisotopes can be produced directly from conventional medical cyclotrons has long been overlooked. Given the shortage of Mo-99 caused by the unexpected prolonged shutdown of the Chalk River reactor, alternative methods of producing technetium radioisotopes would allow continued use of all existing radiopharmaceuticals designed for Tc-99m in nuclear medicine. We do not need to reinvent 50 years of radiopharmaceutical development. Direct on-target production of technetium radioisotopes, notably Tc-99m and Tc-94m has already been achieved in proof-of-principle experiments and provide the simplest solution to the isotope shortage problem. The potential yields of direct Tc production are quite sufficient to manufacture Tc-99m on-site for supplying regional radiopharmacies and hospitals, without the need for Mo-99 generators. The purpose of this proposal is to develop improved methods for cyclotron production of technetium radioisotopes, implement automated methods to extract and purify these radioisotopee and assess their suitability for human use. As an expected deliverable for this project, we plan to manufacture and formulate tehnetium produced directly from a cyclotron and demonstrate its safe use for human subjects.