A Phase I,open label study to assess the safety and tolerability of ZD6474 in combination with 5-Fluorouracil, Leucovorin and Oxaliplatin (mFOLFOX6) as first and second line therapy in patients with advanced colorectal adenocarcinoma.

Inclusion Criteria:

1. Histologically confirmed locally advanced, recurrent or metastatic colorectal adenocarcinoma (Stage IV)
2. WHO performance status 0-1
3. one or more measurable lesions min 10mm by spiral CT or min 20mm by conventional techniques

Exclusion Criteria:

1. Brain metastasis or spinal cord compression unless irradiated at least 4 weeks before entry and stable
2. last dose of prior chemotherapy discontinued at least 4 weeks before start study treatment
3. prior unanticipated severe reaction to oxaliplatin