A Randomized, Multicenter, Open-label Phase II Study of RO5083945 in Combination With FOLFIRI Versus FOLFIRI Plus Cetuximab or FOLFIRI Alone as Second Line Treatment in Patients With KRAS Wild-type or Mutant Metastatic Colorectal Cancer

Inclusion Criteria:

- Adult patients, >/= 18 years of age

- Carcinoma of the colon and/or rectum

- Disease progression during or within 6 months of last dose of oxaliplatin containing
first-line combination therapy for metastatic disease

- ECOG performance status 0-1

- Adequate hematological, renal and liver function

Exclusion Criteria:

- Prior treatment with monoclonal antibody/small molecule against epidermal growth
factor receptor (EGFR)

- Prior treatment with irinotecan

- Radiotherapy within the last 4 weeks before first dose of study drug (except for
limited field palliative radiotherapy for bone pain relief)

- CNS metastasis

- History of or active autoimmune disorders/conditions