The clock starts ticking when
Boston Scientific
‘s TheraSpheres exit the nuclear reactors where they get their cancer-killing radioactivity.
That radioactive power immediately begins to wane due to the half life of yttrium-90, the beta-radiation-emitting isotope in the a glass beads that slow or halt the growth of liver cancer tumors.
“As soon as they come out [of the reactor] they’re starting to decay,” Boston Scientific Interventional Oncology President Peter Pattison said in an interview.
“It’s like we’re shipping ice cubes in the desert,” he continued. “… You have to have a good process.”
Pattison — who previously explained to Medical Design & Outsourcing readers how Boston Scientific’s TheraSphere devices work, how they’re manufactured and what other cancers they might be able to treat — discussed the logistics and supply chain challenges posed by this radioactive medtech.
Nuclear reactors in the supply chain
After the inert TheraSphere glass beads are made, Boston Scientific partners with government-run research reactors to bombard the microscopic devices with neutrons to make them radioactive.
Boston Scientific’s global network of reactors include the Missouri University Research Reactor (MURR), the Petten High Flux Reactor in the Netherlands, and reactors in Australia, Belgium, Poland and South Africa.
“These are very big, very complicated, very regulated facilities. As a result, they will go down for maintenance. Usually it’s planned maintenance, but sometimes something’s come up and they need to shut it down and do a safety check,” Pattison said.
“For us, it’s important to have a network so if we know that a reactor will go down for the next two months, that’s OK because we have four or five other reactors or more that we can draw from. It requires a lot of hand-holding from our supply chain group,” he continued.
“The most fascinating part of the process”
All of the irradiated TheraSpheres then go to Boston Scientific’s dispensing contractor, BWXT Medical, in Ottawa, Ontario. There, BWXT employees dispense and package the radioactive glass beads behind a protective layer of lead glass.
Each dose is packaged in a 100 microliter glass vial with a Lucite shield. (Lucite is a brand name for polymethyl methacrylate, a synthetic polymer also called PMMA.) The vial and shield are packaged in a lead container to block all beta radiation, and then that’s packaged in styrofoam and a bright yellow cardboard box measuring about one cubic foot.
The dispensing employees use manual manipulators rather than electronic systems that would malfunction inside the “hot cell” due to the radiation.
“These very skilled operators are able to open vials, dispense, close vials, move things in and out … remotely with these very sensitive, manual and non-electronic, non-automated manipulators,” Pattison said. “… Our contract manufacturer that does the actual dispensing is probably the most fascinating part of the process.”
Shipping radioactive devices
Boston Scientific aims for the dose to reach the interventional radiologist within two to three days, but can get it to them the next day in an emergency.
“Our ability to move in a timely fashion is world class,” Pattison said. “We’ve had to charter aircraft at the last minute, we’ve had to send people in trucks to go get things. The hero stories — I don’t love when they happen, but I love that they turn out the right way.”
The company uses couriers rather than owning or leasing its own fleet of aircraft or delivery vehicles. To make the shipments easier for couriers to spot if they go missing in a warehouse, Boston Scientific picked a “super-bright, obnoxious” yellow color for the cardboard boxes.
“Having these bright yellow boxes for the couriers is something that’s proved to be quite helpful to us,” he said.
Based on how much radiation is needed for a patient (measured in a unit known as the becquerel, abbreviated Bq) and when the procedure is scheduled to take place, Boston Scientific works out the the transit time from Ottawa, the becquerel needed to arrive with just the right dose, and the chain of custody along the way.
“We just want the customer to worry about the dose and the day and where they are,” Pattison said. “We’ll figure out the rest of that supply chain, work back from the last-mile courier to maybe the trucking company to maybe the airline. It’s really quite astounding the detail that’s required to make sure all these packages get around the world every day.”