Inclusion Criteria:

- Male or female patients, >18 years of age, able to understand and give written
informed consent.

- Histologically or cytologically confirmed colorectal adenocarcinoma.

- Stage IV (metastatic) disease.

- Failed at least one prior standard treatment regimen for colorectal cancer

- Adequate performance status (ECOG 0 or 1)

- Expected survival > 6 months.

- CEA plasma levels > 5 ng/mL

- Measurable disease by CT or MRI

- At least 4 weeks beyond major surgery and recovered from all acute toxicities

- At least 2 weeks beyond corticosteroids, except low doses (i.e., 20 mg/day of
prednisone or equivalent) to treat nausea or other illness such as rheumatoid
arthritis

- Adequate hematology without ongoing transfusional support (hemoglobin > 9 g/dL, ANC >
1,500 per mm3, platelets > 100,000 per mm3)

- Adequate renal and hepatic function (creatinine ≤ 1.5 x IULN, bilirubin ≤ IULN, AST
and ALT ≤ 3.0 x IULN or 5 x IULN if know liver metastases).

- Otherwise, all toxicity at study entry
Exclusion Criteria:

- Women who are pregnant or lactating.

- Women of childbearing potential and fertile men unwilling to use effective
contraception during study until conclusion of 12-week post-treatment evaluation
period.

- Patient's with Gilbert's disease or known CNS Metastatic disease. However, patients
with CNS metastases who are asymptomatic and have completed a course of therapy are
eligible for the study provided they are clinically stable for 1 month prior to entry
as defined as: (1) no evidence of new enlarging CNS metastasis (2) off steroids or on
a stable dose of steroids

- Patients with CEA plasma level > 1000 ng/mL are excluded during dose escalation, but
may be included after the MTD is determined

- Patients with active grade 3 anorexia, nausea or vomiting, and/or signs of intestinal
obstruction.

- Patients with non-melanoma skin cancer or carcinoma in situ of the cervix are not
excluded, but patients with other prior malignancies must have had at least a 3-year
disease free interval.

- Patients known to be HIV positive, hepatitis B positive, or hepatitis C positive.

- Known history of unstable angina, MI, or CHF present within 6 months or clinically
significant cardiac arrhythmia (other than stable atrial fibrillation) requiring
anti-arrhythmia therapy,

- Known history of clinically significant active COPD, or other moderate-to-severe
chronic respiratory illness present within 6 months.

- Known autoimmune disease or presence of autoimmune phenomena (except rheumatoid
arthritis requiring only low dose maintenance corticosteroids, and other than
diabetes, vitiligo, or stable thyroid disease).

- Infection requiring intravenous antibiotic use within 1 week.

- Other concurrent medical or psychiatric conditions that, in the Investigator's
opinion, may be likely to confound study interpretation or prevent completion of
study procedures and follow-up examinations.