The U.S. Food and Drug Administration (FDA) says that Cardiogen-82 problems, which led to a product recall last year, are linked to device misuse. This, following a preliminary agency investigation.
The FDA’s investigation revealed that “improper usage” of the CardioGen-82 generators—a cardiac PET imaging agent—were what led to excessive patient radiation exposure, said DotMed, noting that the recall of the medical device took place last summer.
In its January 12th safety announcement, the FDA said that continuing tests conducted by the nuclear medicine agent’s manufacturer, Bracco Diagnostics Inc., revealed manufacturing “deficiencies” that the FDA said do not appear to be connected to the increased radiation exposure that had been detected in some patients, wrote DotMed.
“None of the tested generators showed signs of [strontium] breakthrough. FDA continues to work with the manufacturer to resolve their manufacturing deficiencies,” the agency said, according to DotMed.
The devices produce rubidium-82 chloride injections, which is, currently, the only commercially available PET agent for myocardial perfusion studies, the Society of Nuclear Medicine explained, added DotMed.
CardioGen-82 is a generator used at clinical sites to produce rubidium (Rb)-82. When extracted from the CardioGen-82, the Rb-82 contains a tiny, fixed amount of strontium-82 and strontium-85, explained MedPage Today. Two sites that the FDA investigated were found to have excessive levels of both compounds in the generators, a so-called “strontium breakthrough.” This phenomena results in radioactive strontium isotopes, which create the PET agent, being injected into patients, explained MedPage Today.
To date, studies conducted by the device maker on 375 patients from 43 clinical sites, revealed that 54 patients required follow-up testing over abnormal screening results, said the FDA in its letter, wrote DotMed. But, noted the FDA, all 54 patients were seen in two sites, which the agency said lack sufficient “documentation of compliance with the CardioGen-82 labeling recommendations” for radiation overexposure testing, according to DotMed.
“FDA continues to work with the manufacturer and other federal agencies to better characterize the problems that led to excessive radiation exposure to patients at certain clinical sites. FDA is also working with the manufacturer to revise the CardioGen-82 labeling to better describe how to use the generator and to implement a plan for the return of CardioGen-82 to the market,” the agency added, wrote DotMed.
The July recall was prompted after two patients set off what DotMed described as “very sensitive radiation detectors” at the United States boarder. This led to FDA notification by the U.S. Dept. of Homeland Security. One patient was stranded in Canada and, ultimately, both were sent to Tennessee’s Oak Ridge National Laboratories for full-body scans, said DotMed. A third patient also reportedly set off alarms. All three underwent Pet stress tests and, later, scans at the same clinic in Florida.