An In Vitro Comparative Study of Three Drug-Eluting Beads Loaded with Raltitrexed

This study investigated the raltitrexed loading method, compatible stability with contrast agent, release profiles, and morphological properties of CalliSpheres, DC Bead, and HepaSphere. The amounts of raltitrexed added, loading medium, loading condition, and drug concentrations were investigated as factors influencing drug loading efficiency. Compatible stability with iopamidol was tested. Release profiles were accessed by a flowthrough apparatus system. Morphological properties were evaluated by a scanning electron microscope (SEM). Diameters were measured by a laser diffraction particle size analyzer. With the optimized method, the amount of raltitrexed loading to a marketed drug-eluting beads (DEBs) package was 2.67 mg for CalliSpheres, 2.34 mg for DC Bead, and 3.19 mg for HepaSphere. For all three DEBs, the drug leak rate was >50% within 2 h after mixing with iopamidol, and the time to reach 75% of the release plateau was within 10 min. Diameters increased after drug loading. Drug crystals were observed on the surface of DEBs in SEM. The amount of drug loading could meet clinical requirements by the optimized method. All three raltitrexed-loaded DEBs showed poor compatible stability with iopamidol, as well as rapid drug release performance, which should be noticed in clinical practice.