* Medical isotope shortage brings delayed, canceled tests
* Shortage could hit drug company clinical trials
By Julie Steenhuysen
CHICAGO, June 12 (Reuters) - A North American shortage of medical isotopes has forced many U.S. hospitals to begin rationing scores of diagnostic tests, and doctors said on Friday they see no quick solution.
Last month, Canadian health officials shut down a nuclear reactor in eastern Ontario that produces a third of the world’s supply of medical isotopes, used in scans to check for an impending heart attack or see if cancer has spread.
Repairs of a leak of heavy water at the Chalk River reactor, first estimated to take a month, may now take three, and Canadian officials say they eventually may leave the isotope business altogether. [ID:nN10440068]
The Canadian plant is one of five aging reactors worldwide -- none located in the United States -- to produce molybdenum-99, the most commonly used medical isotope. The rapidly decaying substance has a shelf life of just 67 hours, making it impossible to stockpile.
“We are seeing a shortage,” said Dr. Peter Conti of the University of Southern California in Los Angeles.
Conti said the university’s three hospitals have begun rationing supplies, and they are not alone.
Conti said a prolonged shortage could threaten clinical trials for cancer drugs because patients may not be able to get needed scans on schedule, forcing them to drop out.
The Society of Nuclear Medicine said 91 percent of 375 members including doctors and nuclear medicine technicians at hospitals across the nation reported in an e-mail survey this week that they had been affected by the shortage, with 60 percent postponing procedures and 31 percent canceling some.
At the University of Chicago Medical Center, doctors are recommending alternative diagnostic tests that do not rely on this medical isotope but may not be as good and may cost more.
“Pretty much every reasonable-sized medical center is going to have a nuclear medicine department that relies very heavily on this isotope,” said Dr. Daniel Appelbaum, who heads the university’s nuclear medicine department.
‘GONE BY THE WAYSIDE’
Conti said doctors at USC are performing only the most urgent tests, typically for heart scans. He said tests to check if cancer has spread to bones “have gone by the wayside.”
He said some cancer patients will be switched to more expensive positron emission tomography scans, known as PET scans. The test is approved by the U.S. Food and Drug Administration, but is not covered by Medicare, the federal health insurance program for the elderly and disabled.
“For Medicare, we’re going to have to eat some of those costs. We’ll try to bill on the private side,” he said.
The shortage has taken a toll on Toronto-based MDS Inc MDS.TO, which distributes medical isotopes worldwide from the Canadian reactor. MDS on Thursday said it lost $17 million in the second quarter. [ID:nN11267505]
Privately held Lantheus Medical Imaging of Massachusetts, which processes isotopes for medical use, got most of its supply from Chalk River. The company last month cut a deal with other suppliers to cope with the impact of the shutdown.
Covidien COV.N, another major U.S. supplier, gets most of its isotopes from a reactor in Petten, the Netherlands, which has shielded its clients somewhat from the Canadian shutdown. But that may change next month when the Dutch reactor goes off line for a four-week maintenance shutdown.
In a May 22 letter on the FDA website, Covidien said, “Even with numerous global efforts and collaborations now underway, there will be challenges meeting full market need.”
Dr. Robert Atcher, president of the Society of Nuclear Medicine, said the nearest-term solution would be to accelerate a U.S. Department of Energy plan to convert a research reactor at the University of Missouri to medical isotopes production.
Without added capacity and a stable domestic supply, he said, patients will be at risk.
Editing by Maggie Fox and Will Dunham