A Phase I Trial of Isolated Hepatic Perfusion (IHP) Using 5-FU and Oxaliplatin in Patients with Unresectable Isolated Liver Metastases from Colorectal Cancer

Background

Isolated hepatic perfusion (IHP) with melphalan is an established approach for patients with unresectable metastatic liver lesions. This study determined the safety and maximum tolerated dose (MTD) of 5-FU with oxaliplatin via IHP.

Methods

Standard 3 × 3 Phase I design. Subjects with unresectable isolated CRC liver metastases scheduled for HAI pump were eligible. IHP used fixed-dose oxaliplatin with escalating 5-FU doses. Toxicity (CTCAE v 4.0) and response (RECIST), progression-free survival, and overall survival (OS) were assessed. Systemic and IHP plasma PK of 5-FU, anabolites, and platinum were determined.

Results

All 12 patients had received ≥1 line of pre-IHP chemotherapy. There were 4 grade 3 serious adverse events (33.3 %) and 1 grade 4 event (8.3 %). Also, 2 dose-limiting toxicities occurred at DL2 at 300 mg/m², resulting in expansion of DL1 at 200 mg/m² 5-FU, the eventual MTD. At 6-month follow-up, 9 patients (82 %) demonstrated partial response, while 2 (18 %) exhibited stable disease. Also, 64 % of patients demonstrated a >50 % decrease in CEA. The 1- and 2-year OS probabilities were 90.9 and 71.6 %, respectively, with median follow-up of 24 months. IHP exposures (AUC_0–60 min) were 10.9 ± 4.5 μgPt h/mL, 49.3 ± 30.7 μg h/mL 5-FU (DL1), and 70.5 ± 35.5 μg h/mL 5-FU (DL2). Systemic exposure (AUC_0–inf) relative to IHP exposure was negligible for both platinum (1.1 ± 1.5 %) and 5-FU (0.09 ± 0.10 %).

Conclusions

The MTD for IHP was 200 mg/m² 5-FU with 40 mg/m² oxaliplatin. Systemic exposure to the agents was minimal during IHP. The response and survival observed warrants assessment in a larger phase II trial.