by Brendon Nafziger
, DOTmed News Associate Editor | February 16, 2012
Bracco Diagnostics Inc. has resumed shipments of its recalled CardioGen-82 generators, which now come with new boxed warnings and quality control guidelines, the company told government officials at a conference Thursday afternoon.
Further tests on the product have also confirmed previous reports that excess radiation levels found in two patients that triggered the voluntary recalls last summer were not indicative of manufacturing problems, the company said.
The "patient incidents are isolated, site-related and not of a product manufacturing nature," said a Bracco slide shown at the public meeting with the U.S. Nuclear Regulatory Commission in Rockville, Md.
The company said it shipped out generators to 27 sites on Feb. 14, the first sites to get shipments since the generators were recalled last summer. Bracco said another batch of 24 shipments was expected soon, and it expects to have the nearly 160 sites that use CardioGen-82 "back on board' by the end of the second quarter.
The generators produce rubidium-82 chloride injections, used in PET heart function scans, and were recalled last July after two patients who had recently undergone the scans triggered sensitive detectors at the U.S.-Canadian border.
The patients were likely affected by what's called a "strontium breakthrough," where radioactive strontium is injected into the patients, resulting in elevated radiation levels. However, the Food and Drug Administration said in announcements last year that the higher radiation levels, while undesirable, did not appear to put the patients in jeopardy. The two patients also came from only two sites: one in Florida, another in Nevada.
On Thursday, Bracco said of the more than 200 recalled generators tested, none had evidence of a strontium breakthrough near the so-called specification levels.
Bracco said, under its revised protocols approved by the Food and Drug Administration, the products carry new boxed warnings of radiation dangers if safety limits are exceeded.
Users also have to abide by a series of new rules.
For one, they need to be re-trained, and technologists and site radiation safety officers need to pass knowledge assessment tests before getting a new shipment of the product. They also must re-take the test every year, Bracco said. Also, providers have to record daily values of volume of product used and levels of strontium, which they'll enter into an online database. Bracco said it would monitor the database, which it's still setting up, to make sure users were following the new guidelines.
Previously, users had to test the generator before use in the morning. Now, they also have to perform additional testing if alert limits are reached. These are reached when levels of strontium isotope 82 exceed 0.002 microcuries per millicurie of rubidium-82 (strontium-85 must exceed 0.02 microcuries), or about one-tenth the legal limit, Bracco said. Alert limits are also reached when total liquid volume exceeds 14 liters passed through the generator columns.
New expiration limits were also set up, Bracco said. The products expire if strontium-82 exceeds 0.01 microcuries per millicurie of rubidium-82 (strontium-85 has to go above 0.1 microcuries), about half of legal breakthrough limits. They also expire if total liquid volume exceeds 17 liters, or if 42 days post-calibration have elapsed, Bracco said. Bracco said only in cases when the product is modestly used, with say four patients per day, would it likely last until the 42nd day.