A Biomarker Study in Patients Getting Regorafenib for Metastatic Colorectal Cancer

Inclusion Criteria: * Metastatic colorectal cancer suitable for regorafenib treatment * Life expectancy of at least 12 weeks * Able to understand and willing to sign written informed consent form * Adequate bone marrow, liver, and renal function * Glomerular filtration rate \>/= 60 according to the Modified Diet in Renal Disease abbreviated formula * Women of childbearing potential must have a negative serum pregnancy test * Subject able to swallow and retain oral medication Exclusion Criteria: * Previous assignment to treatment in this study * Uncontrolled hypertension * Active or clinically significant cardiac disease * Evidence or history of Bleeding diathesis or coagulopathy * Any hemorrhage or bleeding even Grade 3 or higher within 4 weeks prior to start of study medication * Subjects with thrombotic, embolic, venous or arterial events * Subjects with any previously untreated or concurrent cancer * Pheochromocytoma * Known history of human immunodeficiency virus infection or current chronic or active hepatitis B or C infection requiring treatment with antiviral therapy * Ongoing infection Grade 2 or higher * Symptomatic metastatic brain or meningeal tumors * Presence of a non-healing wound, non-healing ulcer, or bone fracture * Renal failure requiring dialysis * Dehydration Grade 1 or higher * Seizure disorder requiring medication * Persistent proteinuria Grade 3 or higher * Interstitial lung disease with ongoing signs and symptoms at the time of informed consent * Pleural effusion or ascites that causes respiratory compromise * History of organ allograft including corneal transplant * Known or suspected allergy or hypersensitivity to the study drug * Any malabsorption condition * Women who are pregnancy or breast-feeding * Substance abuse, medical, psychological or social conditions that may interfere with the subject's participation in the study or evaluation of the study results * Concurrent anticancer therapy * Concurrent use of another investigational drug or device therapy during or within 4 weeks of trial entry * Major surgical procedure, open biopsy, or significant traumatic injury within 28 days before start of study medication * Therapeutic anticoagulation with Vitamin-K antagonists or with heparins and heparinoids * Use of any herbal remedy