Opportunity Amidst Isotope Crisis
June 16, 2009 - “Our profession faces one of the most significant crises in its history,” said Michael Graham, M.D., the new president of the Society of Nuclear Medicine (SNM), as he addressed a room packed with national and international press, hungry for accountability and solutions to the shortage of nuclear medicine radioisotopes.
Since the May 14, 2009, emergency shut down of the National Research Universal (NRU) reactor in Chalk River, Canada, the subsequent worldwide shortage of nuclear radioisotope molybdenum-99 (Moly-99), has become a healthcare problem of international proportions. It was made headline news from the floors of the SNM’s 56th Annual Meeting June 13–17, 2009, in Toronto, where the nuclear medicine thought leaders convened to resolve the issue.
The shut down of the nuclear reactor at Chalk River has spiraled into the depletion of roughly 30-40 percent of the world’s supply of Moly-99, from which technetium-99m (Tc-99m) is derived. Approximately 70-80 percent of all nuclear medicine procedures use Tc-99m used in combination with SPECT and PET imaging to diagnose cancer, and cardiovascular and neurological diseases. Each year more than 20 million people in the U.S., 2 million in Canada, 10 million in Europe, and 14 million in the rest of the world benefit from nuclear medicine tests involving medical isotopes. The shortage has already delayed procedures in Canada and other parts of the world. To further complicate the situation, another major supplier of Moly-99, the Petten reactor located in The Netherlands, which produces 33 percent of global supplies, plans to shut down for maintenance for several days at the end of July. The combined shut down of the Chalk River and Petten plants accounts for an estimated 64 percent deficiency in Moly-99 worldwide.
Yet, Dr. Graham noted that like the Chinese symbol for crisis connotes - where there a crisis there is opportunity. In the case of the radioisotope shortage, there is an opportunity to utilize other resources, and the leaders at SNM are acting quickly to facilitate these opportunities.
SNM has solicited the FDA to approve the use of PET, instead of SPECT, with 18F sodium fluoride (NaF) to replace technetium for MDP bone scans to help offset shortages of molybdenum. The reintroduction of thallium for myocardial perfusion imaging will ease the drain on Moly-99. The society is also working with healthcare leaders to triage patients scheduled for Moly-99 dependant exams to CT and MR.
However, any immediate solution is only a band-aid to the long-term challenges the industry faces with Moly-99 production. The five reactors that produce the nuclear isotope are 45 years-old on average, and are already susceptible to power failures, leaks and other systemic breakdowns. Despite efforts to maintain and modernize these facilities, they are worn down and too undependable to keep up with the growing demand for medical isotopes and, therefore, can no longer be relied on as the sole sources of Mo-99.
“We need to have a stable isotope supply for nuclear medicine to move forward in the field,” said SNM President Robert W. Atcher, Ph.D.
In search of a sustainable supply chain, an SNM task force was created in 2008 to explore alternatives to the world’s aging isotope production facilities, and has identified two alternatives as being the most viable to provide a domestic supply of medical isotopes: the University of Missouri Research Reactor Center (MURR) in Columbia, Mo., and in the longer-term, the Babcock & Wilcox (B&W)-Covidien collaboration. MURR could meet approximately 50 percent of the current market need for Mo-99 with little change to the current reactor.
SNM also recommends that the Department of Energy’s (DOE) National Nuclear Security Administration (NNSA) fund the construction and development of the processing capability, especially since the major thrust of the NNSA is to demonstrate a high-level production path using low enriched uranium (LEU). Success at MURR and by Babcock & Wilcox would reduce the amount of highly enriched uranium (HEU) that is now exported by the U.S. for Mo-99 production by 50 percent.
Canada has mobilized through the appointment of former SNM president Alexander J. (Sandy) McEwan, as special advisor on Medical Isotopes by Canada’s Minister of Health. Dr. McEwan will provide on-the-ground updates on the isotope situation, how it is affecting patient care, and he will advise the health minister on the use of alternatives and mitigation strategies and on short- and long-term strategies for retaining a supply of medical isotopes.
"A continuous supply of medical isotopes is essential to ensure that patients have access to critical nuclear medicine and molecular imaging tools. Dr. McEwan can provide the sound guidance the health minister needs to move forward on these issues," said Dr. Atcher.
Manufacturers are also jockeying to tap into immediate supply chains for both short- and long-term solutions to establishing a reliable supply chain.
Lantheus Medical Imaging will work with the Australian Nuclear Science and Technology Organization (ANSTO) to receive the nuclear imaging radiotracer component Moly-99 produced from low-enriched uranium (LEU) targets in ANSTO’s new OPAL reactor. It will also import the isotope from the SAFARI reactor in Pelindaba, South Africa.
MDS Nordion similarly has upped its imports from the South African reactor to satisfy current orders. As a long-term solution, MDS Nordion and the Karpov Institute of Physical Chemistry in Moscow, Russia, have agreed to study the feasibility of the Karpov Institute providing the company with a flexible, reliable and responsive medical-isotope solution supplier of Moly-99 for the global nuclear medicine market.
PETNET Solutions, a Siemens Medical Solutions subsidiary, said it is prepared to increase production and availability of 18F sodium fluoride (NaF) to replace Technetium for MDP bone scans to help offset shortages of molybdenum, which can result in limited availability of 99mTc-labeled radiopharmaceuticals.
While the nuclear medicine community and Tech-99m providers scramble to replenish current Moly-99 supplies and lay the foundation for a reliable and sustainable supply chain for the future, amidst the crisis the biggest opportunity is for medical imaging to demonstrate to the world its value and importance to global healthcare.