History of transient ischemic attack (TIA), cerebrovascular accident (CVA), gastrointestinal (GI) perforation or arterial thrombotic event within 6 months prior to randomization or symptomatic peripheral ischemia Patients with a history of transient ischemic attack (TIA) or cerebrovascular accident (CVA) within the past 6 months prior to study enrollment are NOT eligible for participation Recent serious cardiovascular events (within 12 months) including, but not limited to, transient ischemic attack (TIA), cerebrovascular accident (CVA), or myocardial infarction (MI). History of thromboembolic or cerebrovascular events within the last 6 months, including transient ischemic attack, cerebrovascular accident, deep vein thrombosis, or pulmonary embolism Known active brain or central nervous system metastasis, or seizures requiring anticonvulsant treatment, cerebrovascular accident, or transient ischemic attack (< 6 months prior to enrollment) Cerebral vascular accident (CVA) or transitory ischemic attack (TIA) in the year before enrollment, or presence of residual symptoms from CVA that happened more than a year before Any history of cerebrovascular accident (CVA) or transient ischemic attack within 12 months prior to registration. History of prior cerebrovascular event, (including transient ischemic attack) within 6 months of start of screening Any history of cerebrovascular accident or transient ischemic attack History of thromboembolic or cerebrovascular events within the last 6 months, including transient ischemic attack, cerebrovascular accident, deep vein thrombosis, or pulmonary embolism (applicable to combination part only). Any history of myocardial infarction (MI), unstable angina, cerebrovascular accident, or Transient Ischemic Attack (TIA) PHASE I STUDY ELIGIBILITY CRITERIA:\r\nHistory of cerebrovascular accident, transient ischemic attack within 1 year prior to study enrollment PHASE II COLORECTAL CANCER COHORT 6 (MEDI+C ONLY):\r\nHistory of cerebrovascular accident, transient ischemic attack within 1 year prior to study enrollment Cerebrovascular accident or transient ischemic attack Cerebrovascular accident or transient ischemic attack within 6 months prior to first dose. History of an ischemic insult in the previous 12 months (myocardial infarction, cerebral vascular accident, ischemic tissue from injury, transient ischemic attack) History of seizures except for remote with specific etiology which has resolved (ex: alcohol induced seizure); transient ischemic attack (TIA) or cerebrovascular accident (CVA) within last 6 months History of transient ischemic attack (TIA) or cerebrovascular accident (CVA) Prior history of cerebrovascular accident or transient ischemic attack. Cerebrovascular accident or transient ischemic attack Patients must have international normalized ratio (INR) =< 1.2 within 14 days prior to registration; patients must not be receiving warfarin for therapeutic use, have history of cerebrovascular accident (CVA), history of transient ischemic attack (TIA) requiring intervention or treatment, pre-existing carotid artery disease requiring intervention or treatment, or current use of megestrol acetate (use within 10 days of registration) History or evidence of thrombotic or hemorrhagic disorders; including cerebrovascular accident (CVA)/stroke or transient ischemic attack (TIA) or sub-arachnoid hemorrhage within =< 6 months prior to the first study treatment Cerebrovascular accident (CVA, stroke), transient ischemic attack (TIA) within 6 months prior to the first date of study therapy. Known active brain or central nervous system metastasis (less than 1 month out from definitive radiotherapy or surgery), or seizures requiring anticonvulsant treatment, or clinically significant cerebrovascular accident or transient ischemic attack (< 3 months) Prior history of cerebrovascular accident or transient ischemic attack, or pre-existing carotid artery disease Patients with a cerebrovascular accident or transient ischemic attack within the past six months History of cerebrovascular attack or transient ischemic attack within 6 months prior to the initiation of therapy on this protocol Cerebrovascular accident or transient ischemic attack within 6 months prior to first dose history of cerebrovascular accident (CVA) or transient ischemic attack (TIA), Prior history of cerebrovascular accident or transient ischemic attack History or evidence of thrombotic or hemorrhagic disorders; including cerebrovascular accident (CVA)/stroke or transient ischemic attack (TIA) or sub-arachnoid hemorrhage within =< 6 months prior to the first study treatment History of cerebrovascular accident, including transient ischemic attack (TIA) History of cerebral vascular accident (CVA) or transient ischemic attack (TIA) =< 6 months prior to randomization History of cerebrovascular accident including transient ischemic attack within the past 12 months Patients with cerebrovascular accident or transient ischemic attack within 6 months of therapy are excluded History of cerebrovascular accident or transient ischemic attack. History of an ischemic insult in the previous 12 months (myocardial infarction, cerebral vascular accident, ischemic tissue from injury, transient ischemic attack. History of cerebrovascular attack or transient ischemic attack within 6 months prior to the initiation of therapy on this protocol. History of prior cerebrovascular accident (CVA), including transient ischemic attach (TIA) Cerebrovascular accident or transient ischemic attack within 2 years History of cerebrovascular accident within the past 6 months (e.g. transient ischemic attack [TIA]) History of dementia, Alzheimer’s disease, multi-infarct dementia or cerebrovascular accident (CVA) (history of transient ischemic attack [TIA] is allowed) Cerebrovascular accident (CVA), transient ischemic attack (TIA) within the last 6 months prior to registration History of cerebrovascular accident or transient ischemic attack within 3 months of first study dose Uncontrolled active seizure disorder or history of cerebrovascular accident (CVA) or transient ischemic (TI) attack within the past 12 months Cerebrovascular accident or transient ischemia.