A Phase I/II Study of Eniluracil Plus Oral 5-Fluorouracil Combined With Oxaliplatin (FOX-E) in Patients With Previously-Treated Colorectal Cancer

OBJECTIVES: I. Determine the maximum tolerated dose, dose limiting toxicity, and recommended phase II dose of eniluracil, fluorouracil, and oxaliplatin in patients with previously treated advanced colorectal cancer. II. Determine the response rate in patients treated with this regimen.

OUTLINE: This is a dose escalation study of eniluracil and fluorouracil. Patients receive oral eniluracil and oral fluorouracil twice daily on days 1-21. Patients receive oxaliplatin IV over 2 hours on days 1 and 15. Treatment continues every 4 weeks in the absence of disease progression or unacceptable toxicity. Patients with complete response are treated with 2 more courses and then therapy is stopped. Cohorts of 3-6 patients receive escalating doses of eniluracil and fluorouracil until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose limiting toxicity. The recommended phase II dose (RPTD) is defined as 1 dose level below the MTD. Patients are followed at 1 month.

PROJECTED ACCRUAL: A total of 3-30 patients will be accrued for phase I of the study, and an additional 27-40 patients will be accrued for phase II of the study.