Cardiogen-82 (rubidium Rb 82 generator)

CardioGen-82 is a closed system used to produce rubidium Rb 82 chloride injection for intravenous administration.

Rubidium Rb 82 chloride injection is indicated for Positron Emission Tomography (PET) imaging of the myocardium under rest or pharmacologic stress conditions to evaluate regional myocardial perfusion in adult patients with suspected or existing coronary artery disease.

WARNING

UNINTENDED STRONTIUM-82 (Sr-82) AND STRONTIUM-85 (Sr-85) RADIATION EXPOSURE

Unintended radiation exposure occurs when the levels of Sr-82 or Sr-85 in the rubidium Rb 82 chloride injection exceed specified limits

Perform generator eluate tests:

1) Record each generator eluate volume, including waste and test volumes, and keep a record of the cumulative eluate volume.

2) Determine Rb-82, Sr-82, Sr-85 in the generator eluate:

• Once a day, prior to any drug administrations, and
• At additional daily tests after detection of an Alert Limit. Alert Limits are:
  • 14 L for the generator's cumulative eluate volume, or
  • An eluate Sr-82 level of 0.002 μCi/ mCi Rb-82, or
  • An eluate Sr-85 level of 0.02 Sr-85 μCi/ mCi Rb-82.
  • Perform the additional daily tests at time points determined by the day's elution volume; tests are performed every 750 mL.

3) Stop use of a generator at an Expiration Limit of:

• 17 L for the generator's cumulative eluate volume, or
• 42 days post generator calibration date, or
• An eluate Sr-82 level of 0.01 μCi /mCi Rb-82, or
• An eluate Sr-85 level of 0.1 µCi /mCi Rb-82.

The following serious adverse reactions have been identified during postapproval use of CardioGen-82. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

• Unintended radiation exposure has occurred in some patients who received rubidium Rb 82 chloride injections at clinical sites where generator eluate testing appeared insufficient.

Infusion System

Use CardioGen-82 only with an infusion system specifically designed for use with the generator and capable of accurate measurement and delivery of doses of rubidium Rb 82 chloride injection. Follow instructions in the Infusion System User's Guide for the set up and intravenous infusion of rubidium Rb 82 chloride injection dose(s).

Rubidium Rb 82 Chloride Injection Dosage

The recommended adult single dose of rubidium Rb 82 chloride injection is 1480 MBq (40 mCi) with a range of  1110-2220 MBq (30-60 mCi).

• Do not exceed a single dose of 2220 MBq (60 mCi).
• Use the lowest dose necessary to obtain adequate cardiac visualization consistent with the dosing goal of as low as reasonably achievable (ALARA).
• Individualize the dose by considering factors such as body size, and the imaging equipment and technique.
• Administer the single dose at 50 mL/minute through a catheter inserted into a large peripheral vein; do not to exceed a total infusion volume of 100 mL.

Administer two separate single doses to complete rest and stress myocardial perfusion imaging as follows:

For rest imaging:

• Administer a single (“rest”) rubidium Rb-82 chloride dose;
• Start imaging 60-90 seconds after completion of the infusion of the rest dose and acquire images for 5 minutes; if a longer circulation time is anticipated (e.g., in a patient with severe left ventricular dysfunction), start imaging 120 seconds after the rest dose.

For stress imaging:

• Begin the study 10 minutes after completion of the resting dose infusion, to allow for sufficient Rb-82 decay;
• Administer a pharmacologic stress agent in accordance with its prescribing information;
• After an interval of 3 minutes, infuse a single (“stress”) rubidium Rb-82 chloride dose;
• Start imaging 60-90 seconds after completion of the stress Rb-82 chloride dose infusion and acquire images for 5 minutes; if a longer circulation time is anticipated start imaging 120 sec after the stress dose.

• It is also not known whether rubidium Rb 82 chloride injection can cause fetal harm when administered to a pregnant woman; however, all radiopharmaceuticals have the potential to cause fetal harm depending on the fetal stage of development and the magnitude of the radiation dose.
• If considering rubidium Rb 82 chloride injection administration to a pregnant woman, inform the patient about the potential for adverse pregnancy outcomes based on the radiation dose from rubidium Rb-82 and the gestational timing of exposure.
• Administer rubidium Rb-82 to a pregnant woman only if clearly needed.
• It is not known whether rubidium Rb 82 chloride injection is excreted in human milk.
• Due to the short half-life of rubidium Rb-82 (75 seconds) it is unlikely that the drug would be excreted in human milk during lactation.
• However, because many drugs are excreted in human milk, caution should be exercised when rubidium Rb-82 chloride injection is administered to nursing women.
• Do not resume breastfeeding until one hour after the last infusion.