Inclusion Criteria:

        Subjects must meet all of the inclusion criteria to participate in this study:

          1. IRB-approved informed consent obtained and signed

          2. Age ≥ 18 years

          3. Histological or cytological documentation of adenocarcinoma of the colon or rectum

          4. Measurable or non-measurable (but evaluable) disease as defined via RECIST 1.1

          5. Metastatic disease not amenable to surgical resection with curative intent

          6. No prior chemotherapy for metastatic disease

          7. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 (see section 11.1,
             Appendix A)

          8. Adequate bone marrow, renal and hepatic function, as evidenced by the following:

               -  absolute neutrophil count (ANC) ≥1,500/mm3

               -  platelets ≥100,000/mm3

               -  hemoglobin ≥9.0 g/dL

               -  serum creatinine ≤1.5 x upper limit of normal (ULN)

               -  AST and ALT ≤3x ULN ( ≤5.0 × ULN for patients with liver involvement of their
                  cancer

               -  Bilirubin ≤1.5 X ULN

               -  Alkaline phosphatase ≤3 x ULN (≤5 x ULN with liver involvement of their cancer)

          9. Willing to undergo UGT1A1 genotyping

         10. Negative pregnancy test (urine or serum), within 7 day prior to Day 1 of FOLFIRI in
             women of childbearing potential

         11. Women of childbearing potential and male subjects must agree to use adequate
             contraception for the duration of study participation. Adequate contraception is
             defined as any medically recommended method (or combination of methods) as per
             standard of care.

        Exclusion Criteria

          1. UGT1A1 genotype other than *1/*1, *1/*28, or *28/*28

          2. Known dihydropyrimidine dehydrogenase (DPD) deficiency

          3. Prior treatment with irinotecan and/or bevacizumab

          4. Unable or unwilling to discontinue (and substitute if necessary) use of prohibited
             drugs for at least 14 days (fruits and juices for at least 7 days) prior to Day 1 of
             FOLFIRI + bevacizumab initiation (see section 11.2, Appendix B, for list of prohibited
             drugs)

          5. Inadequately controlled hypertension (defined as systolic blood pressure > 140 mmHg
             and/or diastolic blood pressure > 90 mmHg)

          6. Prior history of hypertensive encephalopathy

          7. Active cardiac disease including any of the following:

               -  New York Heart Association (NYHA) Grade II or greater congestive heart failure
                  (see section 11.3, Appendix C)

               -  History of myocardial infarction or unstable angina within 6 months prior to Day
                  1

               -  History of stroke or transient ischemic attack within 6 months prior to Day 1 of
                  FOLFIRI + bevacizumab initiation

          8. Significant vascular disease (e.g., aortic aneurysm, requiring surgical repair or
             recent peripheral arterial thrombosis) within 6 months prior to Day 1 of FOLFIRI +
             bevacizumab initiation

          9. History of hemoptysis (≥ 1/2 teaspoon of bright red blood per episode) within 1 month
             prior to Day 1 of FOLFIRI + bevacizumab initiation

         10. Evidence of bleeding diathesis or significant coagulopathy (in the absence of
             therapeutic anticoagulation)

         11. Major surgical procedure, open biopsy, or significant traumatic injury within 28 days
             prior to Day 1 of FOLFIRI + bevacizumab initiation or anticipation of need for major
             surgical procedure during the course of the study

         12. Core biopsy or other minor surgical procedure, excluding placement of a vascular
             access device, within 7 days prior to Day 1 of FOLFIRI + bevacizumab initiation

         13. History of abdominal fistula or gastrointestinal perforation within 6 months prior to
             Day 1 of FOLFIRI + bevacizumab initiation

         14. Serious, non-healing wound, active ulcer, or untreated bone fracture

         15. Proteinuria as demonstrated by:

             Urine protein: creatinine (UPC) ratio ≥ 1.0 at screening OR Urine dipstick for
             proteinuria ≥ 2+ (patients discovered to have ≥2+ proteinuria on dipstick urinalysis
             at baseline should undergo a 24 hour urine collection and must demonstrate ≤ 1g of
             protein in 24 hours to be eligible)

         16. Any serious uncontrolled medical disorder that would impair the ability of the subject
             to receive protocol-driven therapy

         17. Other anti-cancer or investigational therapy while patients are on study therapy