Inclusion Criteria:

          -  Signed written informed consent

          -  Male or female ≥ 18 years of age

          -  Histologically proven metastatic colorectal cancer

          -  Molecular testing showing RAS wild-type in colorectal carcinoma cells

          -  Life expectancy > 12 weeks

          -  At least one measurable lesion according to RECIST 1.1

          -  Adequate bone marrow, liver, kidney, organ and metabolic function

          -  Bone marrow function:

               -  leukocyte count ≥ 3.0 × 109/L

               -  ANC ≥ 1.5 × 109/L

               -  platelet count ≥ 100 × 109/L

               -  hemoglobin ≥ 9 g/dL or 5.59 mmol/L (may be transfused or treated with
                  erythropoietin to maintain/ exceed this level)

          -  Hepatic function:

               -  Total bilirubin ≤ 1.5 × UNL

               -  ALT and AST ≤ 2.5 × UNL (or ≤ 5 × UNL in presence of liver metastases)

               -  AP ≤ 5 × UNL

          -  Renal function:

               -  Creatinine clearance ≥ 50 mL/min according to Cockcroft-Gault formula or serum
                  creatinine ≤ 1.5 × UNL

          -  Metabolic function:

               -  Magnesium ≥ lower limit of normal

               -  Calcium ≥ lower limit of normal

          -  ECOG performance status 0 - 1

          -  Women of child-bearing potential must have a negative pregnancy test

        Exclusion Criteria:

          -  Previous treatment for colorectal cancer in the metastatic setting

          -  Previous EGFR-targeting therapy < 6 months after end of adjuvant therapy

          -  Known brain metastases unless adequately treated (surgery or radiotherapy) with no
             evidence of progression and neurologically stable off anticonvulsants and steroids

          -  Chronic inflammatory bowel disease

          -  Peripheral neuropathy ≥ NCI-CTCAE V 4.03 grade 2

          -  Other previous malignancies with the exception of a history of previous curatively
             treated basal cell carcinoma of the skin or pre-invasive carcinoma of the cervix or
             other curatively treated malignant disease without recurrence after at least 5 years
             of follow-up

          -  Significant disease that, in the investigator's opinion, would exclude the patient
             from the study

          -  History of cardiac disease; defined as:

               -  Congestive heart failure > New York Heart Association (NYHA) class 2

               -  Active coronary artery disease (myocardial infarction more than 6 months prior to
                  start of study treatment is allowed)

               -  Cardiac arrhythmias requiring anti-arrhythmic therapy (beta-blockers or digoxin
                  are permitted)

               -  Uncontrolled hypertension (defined as blood pressure ≥ 160 mmHg systolic and/or ≥
                  90 mmHg diastolic on medication)

          -  Patients with interstitial lung disease, e.g., pneumonitis or pulmonary fibrosis or
             evidence of interstitial lung disease on baseline chest CT scan

          -  Known HIV, hepatitis B or C infection

          -  Known hypersensitivity reaction to any of the study components

          -  Radiotherapy, major surgery or any investigational drug 30 days before registration

          -  Pregnancy or lactation or planning to be pregnant during treatment and within 6 months
             after the end of treatment

          -  Subject (male or female) is not willing to use highly effective methods of
             contraception (per institutional standard) during treatment and for at least an
             additional 6 months after the end of treatment

          -  Known alcohol or drug abuse

          -  Any condition that is unstable or could jeopardize the safety of the patient and his
             compliance in the study