Inclusion Criteria:

- Colorectal adenocarcinoma, Wild KRAS, 18-75 yr

- Estimated life expectancy of more than 3 months

- ECOG performance status of 0 to 1 at study entry

- Adequate bone marrow function

- Adequate liver function

- Documented progression during or within 3 months of irinotecan-containing regimens as
a first-line chemotherapy

- Immunohistochemical evidence of a presence or absence of EGFR expression by PharmDx
Kit

- Informed Consent

Exclusion Criteria:

- Central nervous system (CNS) metastases or prior radiation for CNS metastases.

- Intestinal obstruction or impending intestinal obstruction due to peritoneal
carcinomatosis

- Surgery (excluding biopsy for diagnosis) during 4 weeks prior to inclusion in the
study.

- Evidence of gastrointestinal bleeding

- Exposure to Cetuximab

- Prior administration of monoclonal antibodies, EGFR signal transduction inhibitors or
EGFR-targeted treatment

- KRAS mutant Status

- Patients with serious toxicity to previous irinotecan-based chemotherapy

- Other serious illness or medical conditions