Aim: To evaluate the pharmacokinetic profile (PK) and embolization effect of 70-150-μm doxorubicin eluting beads (DEBs) following intra-arterial injection (i.a.) in the rabbit liver VX2 tumour model.
Materials and methods: In this ACUC-approved study, 25 white New Zealand rabbits were randomly assigned into a small DEB group (SDB, n = 7, 70-150-μm DEBs), large DEB group (LDB, n = 7, 100-300-μm DEBs), untreated controls (n = 7), and doxorubicin controls (n = 4, without tumour, received i.a. 12.5 mg doxorubicin). Plasma PK was assessed up to 180 min post-injection. Drug tissue and liver enzyme levels, radiologic tumor response and histopathologic tumour necrosis were assessed at 7 days.
Results: Mean tumour doxorubicin concentrations were 922.83 nM (SD = 722.05) and 361.48 nM (SD = 473.23) for the SDB and LDB, respectively (p = 0.005). There was no statistically significant difference in tumour doxorubicinol, plasma doxorubicin and doxorubicinol PK values. More beads were observed in the SDB tumours (p = 0.01). Liver enzymes increased and gradually declined over the observation period, with significantly higher values in the SDB.
Conclusion: In this preclinical study, plasma PK of i.a.-injected 70-150-μm DEBs was not different than that of 100-300-μm DEBs. More beads and higher tissue doxorubicin levels were observed in the SDB tumours.
Key points: • Small and large doxorubicin-eluting beads show similar plasma pharmacokinetic profiles. • Higher tissue doxorubicin levels were observed in the small bead group. • Liver enzymes were overall significantly higher in the small bead group.
Keywords: Doxorubicin; Drug-eluting beads, DEBs; Injections, intra-arterial; Liver neoplasms; Microspheres.