A Trial to Compare Oxaliplatin, Folinic Acid (FA) and 5-Fluorouracil (5FU) Combination Chemotherapy (FOLFOX-4) With or Without Cetuximab in the 1st Line Treatment of Metastatic Colorectal Cancer (mCRC) in Chinese Rat Sarcoma Viral Oncogene Homolog (RAS) Wild-type Patients

Inclusion Criteria: * Signed written informed consent (first and second) * Chinese with Chinese citizenship * Male or female subjects greater than or equal to (\>=) 18 years of age * Medically accepted effective contraception if procreative potential exists (applicable for both male and female subjects until at least 90 days after the last dose of trial treatment) * Diagnosis of histologically confirmed adenocarcinoma of the colon or rectum * First occurrence of metastatic disease (not curatively resectable) RAS wild-type status in tumor tissue * At least one measurable lesion by computer tomography (CT) or magnetic resonance imaging (MRI) according to RECIST (not in an irradiated area) * Life expectancy of at least 12 weeks * Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 at trial entry * White blood cell count \>= 3 × 10x9/L with neutrophils \>= 1.5 × 10x9/L, platelet count \>= 100 × 10x9/L and hemoglobin \>= 6.21 mmol/L (10 g/dL) * Total bilirubin \<= 1.5 × upper limit of reference range * Aspartate transaminase (AST) and alanine transaminase (ALT) \<= 2.5 × upper limit of reference range or \<= 5 × upper reference range in subjects with liver metastasis * Serum creatinine \<= 1.5 × upper limit of reference range * Recovery from relevant toxicity due to previous treatment before trial entry Exclusion Criteria: * Previous chemotherapy for CRC except adjuvant treatment if terminated \> 9 months (oxaliplatin-based chemotherapy) or \> 6 months (non-oxaliplatin-based chemotherapy) before the start of treatment in this trial * Radiotherapy or surgery (excluding prior diagnostic biopsy) in the 30 days before trial treatment * Previous treatment with monoclonal antibody therapy, vascular endothelial growth factor (VEGF) pathway-targeting therapy, epidermal growth factor receptor (EGFR) pathway-targeting therapy, or other signal transduction inhibitors * History of organ allograft, autologous stem cell transplantation, or allogeneic stem cell transplantation * Renal replacement therapy * Intake of any investigational medication within 30 days before trial entry * Concurrent chronic systemic immune therapy or hormone therapy except physiologic replacement * Granulocyte colony stimulating factor (G-CSF) or granulocyte macrophage colony stimulating factor (GM-CSF) within 3 weeks of trial entry (these growth factors may be used during the trial thereafter) * Other non-permitted concomitant anticancer therapies * Known brain metastasis and/or leptomeningeal disease. Subjects with neurological symptoms should undergo a CT scan/MRI of the brain to exclude brain metastasis * Previous malignancy other than CRC in the last 5 years except basal cell cancer of the skin or preinvasive cancer of the cervix * Clinically significant cardiovascular disease, e.g. cardiac failure of New York Heart Association classes III-IV, uncontrolled coronary artery disease, cardiomyopathy, uncontrolled arrhythmia, uncontrolled hypertension, or history of myocardial infarction in the last 5 years, or left ventricular ejection fraction below the institutional range of normal on a baseline multiple gated acquisition scan or echocardiogram * Acute or sub-acute intestinal occlusion or history of inflammatory bowel disease * Active clinically serious infections (\> grade 2 National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 3.0), including active tuberculosis * Known and declared history of human immunodeficiency virus (HIV) infection or chronic hepatitis B or C * Peripheral neuropathy \> grade 1 * Signs and symptoms suggestive of transmissible spongiform encephalopathy, or family members who suffer(ed) from such * Uncontrolled diabetes mellitus, pulmonary fibrosis, acute pulmonary disorder, interstitial pneumonia, or liver failure * Known hypersensitivity or allergic reactions against any of the components of the trial treatments * Pregnancy (absence to be confirmed by serum β-human chorionic gonadotropin test) or breastfeeding * Ongoing alcohol or drug abuse * Presence of a medical or psychological condition that would not permit the subject to complete the trial or sign informed consent * Participation in another clinical trial within the past 30 days * Other significant disease that in the investigator's opinion should exclude the subject from the trial * Legal incapacity or limited legal capacity