Phoenix and SHINE Medical face the key challenge of producing the Mo-99 Isotope, which is derived from uranium. The Uranium they have been using for this process comes from decommissioned nuclear bombs and it requires a lot of neutrons (which historically could only be produced by nuclear reactors).
The U.S. consumes more than half of the global Mo-99 supply. To help to address supply issues, the innovation aims to help to help to meet the global need for nuclear medicine.
To learn more, Digital Journal spoke with Greg Piefer, founder and CEO, SHINE Medical and Evan Sengbusch, PhD, MBA, President, Phoenix.
Digital Journal: What are medical isotopes used for?
Greg Piefer: Medical isotopes are used in medical imaging procedures such as SPECT (single-photon emission computed tomography) scans. Medical professionals create images of the structures inside your body—your skeletal, circulatory, and lymphatic systems; your organs, etc.—by measuring the emissions of medical isotopes that you ingest or is injected into your body before the imaging procedure.
Radioactive, unstable variations of normally stable elements called radioisotopes are used for a variety of applications, but few are suitable for medical imaging. Medical radioisotopes, such as technetium-99m, the decay product of Mo-99, are ideal because they decay in only a few hours which is enough time to provide detailed information while deteriorating in an appropriate time.
If a radioisotope decays back to its stable form too quickly, the doctors will not receive enough data needed for a complete scan. Conversely, if a radioisotope decays too slowly, the patient will be exposed to more radiation that strictly necessary.
DJ: Why are there shortages in many countries?
Evan Sengbusch: There have been multiple medical isotope shortages since 2009 and there are major two reasons why these shortages keep reoccurring. First, as technology advances and medical imaging procedures become more commonplace, the global demand for isotopes, a requirement for these procedures, also rises and begins to outstrip supply. The United States alone consumes half of the global patient demand for medical isotopes, but produces none of its own.
Second, because the isotopes decay in a matter of hours, they cannot be stockpiled. There is no way to arrest the natural process of radioactive decay that results in these radioisotopes breaking down and becoming useless in a matter of hours. Facilities must continuously produce isotopes to create the ability to “stockpile” them.
Molybdenum-99 has a half-life of 66 hours and decays to Tc-99m, with a half-life of roughly six hours, neither of which can be stored. Further complicating matters, Mo-99 is only produced at a significant scale in a handful of nuclear reactor facilities around the world. There are no sources of Mo-99 in the Western Hemisphere. Between the logistical difficulties of this arrangement coupled with aging nuclear reactors, it is critical that the United States creates a domestic supply.
DJ: How did Phoenix and SHINE Medical team up?
Sengbusch: Dr. Greg Piefer, who holds a doctorate from the University of Wisconsin-Madison’s nuclear engineering program founded Phoenix in 2005 with a grant from the DOE to work towards a domestic supply of Mo-99 that did not rely on nuclear reactors. Piefer spun SHINE off from Phoenix in 2010 to focus solely on medical isotope production while Phoenix broadened its focus to other high-yield neutron applications outside of medicine like industrial neutron radiography.
Each organization offers key contributions to the Mo-99 supply chain and their collaboration is paramount in addressing both U.S. and global demand. Phoenix’s high-yield fusion neutron generators drive the SHINE isotope production system. SHINE’s system uses the neutrons produced by this reaction to strike a SHINE target of low-enriched uranium (LEU) that is dissolved in a water-based solution to produce moly-99.
When SHINE’s production facility in Janesville comes online in 2021, it will house eight of Phoenix’s generators and be capable of providing up to one-third of the global patient need for Mo-99.
DJ: What have been the challenges around sourcing the Mo-99 Isotope?
Piefer: Inside a nuclear reactor, enriched uranium atoms are split in fission reactions. When the atoms split, they leave behind new, lighter elements and isotopes, one of which is molybdenum-99. For decades, the only source of Mo-99 was nuclear reactors. If one of the world’s handful of working Mo-99 producing reactors encounters an unexpected problem and needs to be shut down for even a few days, the steady trickle of Mo-99 to world is disrupted. The world’s nuclear reactor infrastructure is aging, leaving the supply chain of Mo-99 in a precarious state.
DJ: How do you get hold of the necessary material?
Piefer:Isotope producing nuclear reactors use high quantities of enriched uranium (HEU). However, HEU is also a global security threat as it can be used for nuclear weapons, should it fall into the wrong hands.
SHINE will be participating in a program of the U.S. government that seeks to remove weapons-grade uranium from the world. SHINE will be using low-enriched uranium (LEU), which contains far less U-235 than that used in power plants and nuclear weapons. The LEU that SHINE uses will have started as weapons-grade uranium that has been down-blended by the U.S. government. With the help of the government, SHINE is taking one of the most potent and feared destructive materials and turning it into the linchpin of lifesaving medical treatments, literally turning bombs into medicine.
DJ: What hurdles did you face in getting permission?
Sengbusch:Getting approval to build a medical isotope production facility is a long process. SHINE’s construction permit was issued by the Nuclear Regulatory Commission in 2016—the first permit granted for a new isotope production facility in fifty year. In 2019, SHINE broke ground on the site of its future production facility. In October 2019, the NRC accepted SHINE’s application for an operating license to run the production facility, which begins another review process.
Phoenix and SHINE wouldn’t be going through it and all of the hurdles yet to come if we didn’t believe wholeheartedly that we were going to change the world for the better.
