Collaboration begins on U.S. Mo-99 production facility

An experienced radiopharmaceutical manufacturer and a leading nuclear power plant builder have joined forces to bring back molybdenum-99 production to the U.S.

Covidien and Babcock & Wilcox Technical Services Group announced Jan. 26 that they have agreed to jointly develop technology to produce Mo-99, the parent isotope of technetium-99m, the primary isotope used in diagnostic nuclear imaging.

Under the agreement, B&W TSG and Mallinckrodt, a subsidiary of Covidien, will work together on an aqueous homogeneous reactor design originally developed by B&W in the 1950s. Also called a solution reactor, the configuration potentially bypasses many pitfalls encountered with conventional fission reactors during the production of Mo-99.

"It has numerous benefits, one being its smaller scale: its cost-effectiveness, its generation of less waste, and its ability to use low-enriched uranium, a factor that addresses concerns about using high-enriched uranium," said Dale Simpson, Covidien's manager of R&D.

The reliance of most existing production facilities on high-enriched uranium is a national security concern that led Congress to ban HEU exports and then exempt shipments to Canada, the Netherlands, and other U.S. allies to assure continued Mo-99 supplies.

A 200-kw aqueous homogeneous reactor is theoretically efficient enough to produce about 1100 six-day curies of Mo-99 per week. It would meet about 20% of current U.S. demand. The B&W TSG/Mallinckrodt collaboration has the potential to supply more than 50% of U.S. demand, according to the companies.

U.S. hospitals and clinics have relied on foreign sources of Mo-99 since the last domestic production facility closed in 1989. Their vulnerability to Mo-99 shortages has been underscored by the current five-month safety-related closure of the High Flux Reactor at Petten in the Netherlands. A month-long shutdown of the 45-MW National Research Universal reactor at Chalk River, ON, in Canada, in late 2007 stirred calls by the SNM and others for a new U.S.-based producer.

The HFR at Petten is a major source of Mo-99 for Covidien. The supply disruption from the Petten shutdown did not influence Covidien's decision to collaborate with B&W, according to Simpson. Negotiations between Covidien and B&W TSG began before the reactor shutdown.

Covidien refines and purifies the isotope at a processing plant in the Netherlands. The agent is then flown to manufacturing facilities at Maryland Heights, MO, where it is inserted in Tc-99m generators for distribution to nuclear imaging services.

Access to a domestic production source would cut transportation times and reduce the amount of radioactive isotope that decays before distribution, according to Simpson.

Covidien will contribute expertise with Mo-99 purification, processing, transportation, and regulatory affairs to the partnership, Simpson said. B&W has a long history in nuclear power as a designer and builder of civilian nuclear reactors for electrical power generation and as a nuclear power plant provider to the U.S. Navy.

"We feel we have a very good combination between the two companies for working together on this development and commercialization effort," he said.

Project costs will be far in excess of $100 million, said S. Robert Cochran, president of B&W TSG. The company is entering a 12 to 18-month development phase in which remaining questions about the reactor's design configuration and how to conduct isotope separation will be addressed.

A number of undisclosed sites in the U.S. are under consideration for the reactor and processing facilities. The plant may be ready for production in five or six years, Simpson said.

For more information from the Diagnostic Imaging and SearchMedica archives:

High-volume production of Mo-99 appears feasible with low-grade uranium

European Mo-99 production at Petten may resume in February

SNM panel finds no easy path to expand molybdenum-99 supplies