An In Vitro Evaluation of Four Types of Drug-Eluting Embolics Loaded with Idarubicin

Purpose: This study compared loading, elution, and stability of drug-eluting embolic beads (DEBs) loaded with idarubicin. Materials and Methods: DC Bead (100-300 mu m), HepaSphere (30-60 mu m), LifePearl (200 mu m), and Tandem (100 mu m) DEBs were loaded with 5 mg/mL idarubicin. Loading, elution, diameter changes, loading stability over 2 weeks in storage, and time in suspension were determined for each of the DEBs. Results: Loading of more than 99% of idarubicin was achieved within 15 minutes for LifePearl, DC Bead, and Tandem beads. LifePearl, DC Bead, HepaSphere, and Tandem beads eluted 75% of the total idarubicin released in 13, 24, 42, and 91 minutes, respectively. In vitro elution was completed in 2 hours with 73% +/- 3%, 74% +/- 3%, 65% +/- 6%, and 7% +/- 0% of the loaded idarubicin eluted for LifePearl, DC Bead, HepaSphere, and Tandem, respectively. Statistically significant differences were observed at every time point between at least 2 of the products. Overall, in vitro idarubicin elution was rapid and nearly complete for LifePearl, DC Bead, and HepaSphere beads but was minimal and slow from Tandem beads. The average diameter of DEBs after loading was reduced by 5% for LifePearl, whereas it was increased by 9% and 1% for DC Bead and Tandem, respectively. After loading, time in suspension was 11 +/- 4 and 10 +/- 2 minutes for LifePearl and HepaSphere, respectively, whereas DC Bead and Tandem beads were held in suspension for greater than 20 minutes. Conclusions: Although all 4 DEBs loaded idarubicin within 15 minutes with minimal changes in diameter, the elution amounts, rates of release, and time in suspension varied.