OBJECTIVES: I. Determine the maximum tolerated dose of raltitrexed when administered with fluorouracil in patients with advanced colorectal carcinoma. II. Determine the toxicity and safety of this regimen in these patients. III. Assess, in a preliminary manner, the antitumor activity of this regimen in these patients.
OUTLINE: This is a dose-escalation study of raltitrexed. Patients receive raltitrexed IV over 15 minutes followed 24 hours later by fluorouracil IV. Treatment continues every 3 weeks in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses of raltitrexed until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose immediately preceding that at which 2 of 6 patients experience dose-limiting toxicity. An additional 6-10 patients are treated at the MTD. Patients are followed for 6 weeks.
PROJECTED ACCRUAL: A total of 20-40 patients will be accrued for this study within 5-20 months.