Irinotecan drug-eluting beads in the treatment of chemo-naive unresectable colorectal liver metastasis with concomitant systemic fluorouracil and oxaliplatin: results of pharmacokinetics and phase I trial.

PURPOSE: The primary objective of this study is to evaluate the safety, tolerance, and pharmacokinetic profile of liver-directed therapy with drug-eluting beads irinotecan (DEBIRI) in combination with systemic modified FOLFOX in the treatment of unresectable liver metastases in chemotherapy-naive patients with colorectal cancer.
DESIGN: DEBIRI, loaded with 100 mg irinotecan (100-300 μm beads), was administered via hepatic artery during the off week of FOLFOX therapy. Primary endpoints were safety, tolerance, systemic dose-limiting toxicities, and pharmacokinetics of systemic irinotecan and its active metabolite SN-38 at each infusion at 1-, 4-, and 24-h post-DEBIRI. Secondary endpoints were response rate and survival.
RESULTS: The ten patients have undergone at least 12 cycles of FOLFOX in combination with at least two DEBIRI bead treatments during the patients' off week. Pharmacokinetic data has demonstrated minimal detectable levels of irinotecan (18.6, 21, and 18.6 ng/ml) and SN-38 (1.06, 1.47, and 1.55 ng/ml) after the first, second, and third DEBIRI treatments, respectively. Currently, there has been only one severe device-related adverse event, a grade 3 hypertensive episode that required 1 day of observation in the hospital. The initial 9- and 12-month response rates have been 100 % (2 CR, 8 PR). Four (40 %) patients were successfully downstaged to resection and/or ablation with a median overall survival of 15.2 months.
CONCLUSION: Concomitant DEBIRI and FOLFOX±bevacizumab is safe, with a minimal adverse event rate, no dose-limiting toxicities, and enhanced overall response rate.