Inclusion Criteria:

- Signed written informed consent.

- Female patients of childbearing potential (and if appropriate male patients with
female partners of childbearing potential) must be willing to use an adequate method
of contraception for 4 weeks prior to, during and 12 weeks after the last dose of
trial medication. A negative pregnancy test is required for female subjects.
Adequate contraception for female subjects is defined as two barrier methods, or one
barrier method with a spermicide, or intrauterine device or use of hormonal female
contraceptive.

- Histologically confirmed diagnosis of adenocarcinoma of the colon or rectum with
complete resection of primary tumor and no evidence of local relapse.

- Metastatic disease of the liver, with recent (< 8 weeks prior to randomization), both
primary or secondary resection (R0 or R1) of all liver metastases. Metastasectomy may
have been either synchronous or metachronous. Neoadjuvant therapy may have been
applied prior to metastasectomy.

- Subject has had a colonoscopy or rectoscopy within the last three months prior to
initiation of therapy

- Subject has an ECOG performance status of 0 or 1.

- Subject has adequate hematologic, hepatic, and renal function within 2 weeks prior to
initiation of therapy as defined by the following: Absolute neutrophils > 1,500/mm3
and platelets > 140,000/mm3. Bilirubin < 1.5 x upper limit of normal (ULN). AST and
ALT < 2.5 x ULN. Creatinine < 1.5 x ULN. International Normalized Ratio (INR) and
partial thromboplastin time (PTT) in the normal range of the local lab.

- Willingness to comply with study protocol requirements.

Exclusion Criteria:

- Metastases other than liver metastases.

- R2 and Rx resected liver metastases. Patients with R1 resected liver metastases can
be included if a further surgical resection is seen as not indicated or necessary in
the surgeon´s opinion.

- Chemotherapy within 4 weeks prior to randomization.

- Receipt of immunotherapy (e.g. interferons, tumor necrosis factor, interleukins, or
growth factors [GM-CSF, G-CSF, M- CSF], monoclonal antibodies) within 4 weeks (28
days) prior to randomization.

- Any known autoimmune disease, past or current.

- A recognized immunodeficiency disease including cellular immuno-deficiencies,
hypogammaglobulinemia or dysgammaglobulinemia; hereditary or congenital
immunodeficiencies.

- Known or newly diagnosed active hepatitis B infection and/or hepatitis C infection,
autoimmune hepatitis, known human immunodeficiency virus infection, or any other
infectious process that in the opinion of the investigator could compromise the
subject's ability to mount an immune response, or expose him/ her to likelihood of
more and/or severe side effects.

- Past or current history of malignant neoplasm other than CRC, except for curatively
treated non-melanoma skin cancer, in-situ carcinoma of the cervix or other cancer
curatively treated and with no evidence of disease for at least 5 years.

- Medical or psychiatric conditions that would interfere with ability to provide
informed consent, communicate side effects, or comply with protocol requirements.

- Clinically significant cardiac disease, e.g. cardiac failure of New York Heart
Association classes III-IV; uncontrolled angina pectoris, uncontrolled arrhythmia,
uncontrolled hypertension, myocardial infarction in the previous 12 months as
confirmed by an ECG.

- Splenectomy.

- Previous (less than 4 weeks prior to randomization) or concurrent treatment with a
non-permitted drug.

- Pregnancy and lactation period.

- Participation in another clinical study within 30 days prior to randomization.

- Known hypersensitivity to the study treatment drugs.

- Known alcohol or drug abuse.

- Legal incapacity or limited legal capacity.

- Any other reason that, in the opinion of the investigator, precludes the subject from
participating in this study.