Speaker
Adriano Duatti
(International Atomic Energy Agency (IAEA))
Description
Progress in nuclear medicine has been always closely connected to the availability of a variety of radionuclides having both suitable decay characteristics and chemical properties to allow the development of useful diagnostic and therapeutic agents. Since there’s no ‘universal’ radionuclide capable to cover all clinical needs and imaging applications, nuclear medicine still relies on the supply of a number of radioisotopes having different roles and relative clinical importance. For instance, despite the current emphasis on PET, Tc-99m still remains a key radionuclide for nuclear imaging with SPECT, and the recent decline of reliability of the supply chain of the father nuclide Mo-99, due to unexpected and extended shutdowns at the few ageing research reactors and processing facilities, has caused serious problems and patient’s damage particularly in those countries placed at the outskirts of the radioisotope market. Similarly, the complexity of cyclotron-based technology required for the production of positron-emitting radionuclides like F-18 and C-11, has partially hampered and slowed down the growth and diffusion of diagnostic PET in those countries having a limited network of nuclear medicine centres. In this respect, the introduction of the Ge-68/Ga-68 transportable generator system has provided a new convenient option for the widespread application of a new class of PET radiopharmaceuticals.
The need of novel radiolabelled agents appears particularly urgent in the field of radionuclide therapy. Although radioiodine therapy is a well-established protocol, this specialty can be still considered in its infancy mainly because of the difficulties supplying some relevant radioisotopes like Y-90 and Re-188. Recently, Lu-177 has attracted much interest due to the favourable nuclear properties and ease of production through conventional research reactors. Since lutetium shares common chemical properties with yttrium, the investigation of the clinical efficacy of analogous pairs of radiotherapeutic agents labelled with Y-90 and Lu-177 is currently an active field of research. It is also worth mentioning the rapid surge of interest in copper radiopharmaceuticals labelled with Cu-64 or Cu-67. The rich chemical behaviour of the element copper combined with the attractive nuclear characteristics of many radioisotopes has strongly stimulated the research for this new class of radiopharmaceuticals and some promising product is already in the pipeline.
In order to promote the introduction in Member States (MS) of new diagnostic and therapeutic approaches based on the use of radiolabelled compounds, IAEA is deeply committed in the widespread development of national and regional capacity building of reliable sources of medical radionuclides. This objective is commonly pursued through the implementation of both national and regional projects and by promoting research investigations in the field of radiopharmaceuticals by means of Coordinated Research Projects involving a remarkable number of MS. All main topics and developments are currently covered by on-going and programmed projects including the most relevant and promising radionuclides cited above. To mention a few examples, IAEA is supporting (i) the search of alternative methods of production of Mo-99 and Tc-99m including accelerator-based technologies, (ii) the assessment of the clinical utility of antibody- and peptide-based Lu-177 radiopharmaceuticals, (iii) the optimization of the performance of the Ge-68/Ga-68 and Sr-90/Y-90 generator systems through the application of advanced separation methods, and (iv) the search of novel agents labelled with Cu-64 and Re-188.
Author
Adriano Duatti
(International Atomic Energy Agency (IAEA))
