Vaccine Therapy and Chemotherapy With or Without Tetanus Toxoid Compared With Chemotherapy Alone in Treating Patients With Metastatic Colorectal Cancer

RATIONALE: Vaccines may make the body build an immune response to kill tumor cells. Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Tetanus toxoid may make tumor cells more sensitive to chemotherapy and vaccine therapy. PURPOSE: Randomized phase II trial to study the effectiveness of chemotherapy and vaccine therapy with or without tetanus toxoid compared with chemotherapy alone in treating patients who have metastatic colorectal cancer.

OBJECTIVES: * Determine the safety of ALVAC-CEA-B7.1 vaccine and chemotherapy, with or without tetanus toxoid, vs chemotherapy alone in patients with metastatic colorectal adenocarcinoma. * Determine whether tetanus toxoid enhances the immune response in patients treated with the vaccine and chemotherapy. OUTLINE: This is a randomized, open-label, multicenter study. Patients are randomized to 1 of 3 treatment arms. * Arm I: Patients receive a priming dose of tetanus toxoid. Beginning 2 weeks later, patients receive tetanus toxoid and ALVAC-CEA-B7.1 vaccine subcutaneously (SC) once weekly for 3 weeks. Two weeks after the third vaccine administration, patients receive tetanus toxoid and ALVAC-CEA-B7.1 vaccine SC on day 1 and irinotecan IV over 90 minutes, leucovorin calcium IV, and fluorouracil IV on days 1, 8, 15, and 22. Treatment repeats every 6 weeks for 4 courses in the absence of disease progression or unacceptable toxicity. * Arm II: Patients receive ALVAC-CEA-B7.1 vaccine and chemotherapy as in arm I. * Arm III: Patients receive chemotherapy as in arm I. After completion of chemotherapy, patients with partial or complete response may receive ALVAC-CEA-B7.1 vaccine SC once weekly on weeks 1-3 and 6. PROJECTED ACCRUAL: A total of 90 patients (30 per treatment arm) will be accrued for this study.