The U.S. Food and Drug Administration (FDA) has confirmed that the "improper usage" of Bracco Diagnostics' CardioGen-82 cardiac PET radiopharmaceutical caused three patients from two different facilities to have increased levels of radiation in their bodies following PET scans.
Preliminary information from investigations conducted by the FDA and Bracco found that the increased radiation exposure was due to the administration of CardioGen-82 generator eluates that contained excessive concentrations of strontium-82 (Sr-82) and strontium-85 (Sr-85), a phenomenon called "strontium breakthrough." The FDA concluded that it is "unlikely" that the excessive exposure posed any significant health risk to patients.
In July 2011, the FDA identified possible deficiencies with Bracco's manufacturing processes for CardioGen-82. The company then voluntarily recalled the generators from its customer sites.
Bracco's ensuing probe last month found that all CardioGen-82 generators had Sr-82 and Sr-85 levels "well within specification limits set forth in the prescribing information," and its generators were not to blame for the patients' excess radiation levels, according to a December 29 letter sent to customers. In addition, data from customer sites showed no other patients with higher-than-expected radiation levels.
Bracco and the FDA are working to revise CardioGen-82's labeling to better describe how to use the generator and to implement a plan for the return of CardioGen-82 to the market.
Bracco expects the radiopharmaceutical to be available before the end of the first quarter.
