The objectives of this trial are to determine if CoFactor in combination with 5-FU are effective in the treatment of metastatic colorectal cancer and to determine the side effects observed with the administration of CoFactor and 5-FU.

Inclusion Criteria:

• Patients must have surgically incurable colon or rectal adenocarcinoma
• Karnofsky Performance Status of 60% or greater
• Patients may have symptomatic neuropathy
• Patients must have a life expectancy of at least 4 months
• Patients must be alimenting, receiving at least 1500Kcal/day nutrition, by any route
• Patients must have bidimensional measurable disease for response assessment
• Patients may have received adjuvant chemotherapy with fluoropyrimidine therapy
• Patients must have recovered from the toxicities of prior therapy, at least 4 weeks since prior adjuvant chemotherapy and major surgery
• Serum creatinine less than 2.4mg%, serum bilirubin less than 3.0mg%, WBC greater than 3,200/mm2, AGC greater than 1,500/mm3, platelet count greater than 90,000/mm3 and SGOT (AST) and SGPT (ALT) less than 3 times the upper limit of normal
• Male and non-pregnant, non-lactating female patients must be >18 years old.

Exclusion Criteria:

• Concurrent infection
• Failure of the patient or the patient's legal representative to sign the Informed consent
• Inability to obtain Informed Consent because of psychiatric or complex medical problem
• Patients with unstable oncologic emergency
• Patients with unstable medical conditions such as angina, transient ischemic attacks, rising creatinine, accelerated hypertension, etc.
• Cerebellar neurologic syndromes such as Parkinson's Disease, multiple sclerosis and amyotonia
• Known intolerance to fluoropyrimidine therapy suggestive of dihydropyrimidine dehydrogenase deficiency.