Inclusion Criteria:

- Inclusion Criteria

Patients may be entered in the study only if they meet all of the following criteria:

1. Male or female patient greater than or equal to 18 years of age;

2. Histologically or cytologically confirmed nonresectable locally advanced or
metastatic colorectal adenocarcinoma;

3. Patients must have failed a first-line chemotherapy regimen for nonresectable locally
advanced or mCRC (first-line 5-FU-based therapies, including but not limited to
FOLFOX, FOLFOX 4, mFOLFOX6, CapeOX, single-agent capecitabine, infusional 5-FU, or
other chemotherapies. Bevacizumab, cetuximab, panitumumab, and EGFR inhibitors are
allowed. Prior treatment with irinotecan or FOLFIRI is not allowed for Phase II).
For Phase Ib only, up to 3 prior therapies are allowed (including non-irinotecan
containing therapies and adjuvant therapy);

4. At least 1 site of measurable disease by the Response Evaluation Criteria in Solid
Tumors (RECIST version 1.1) criteria;

5. Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of less than or
equal to 2;

6. Patients must have adequate renal function as evidenced by serum creatinine <2 mg/dL
and creatinine clearance >50 mL/minute per the Cockcroft and Gault formula;

7. Patients must have adequate bone marrow function as evidenced by absolute neutrophil
count (ANC) ≥1.5 x 109/L, platelets >100 x 109/L, hemoglobin ≥9.0 g/dL (a hemoglobin
<9.0 g/dL at Screening is acceptable if it is corrected to

≥9 g/dL by growth factor or transfusion prior to the first dose);

8. Patients must have adequate liver function as evidenced by bilirubin ≤1.5 times the
upper limit of the normal range (ULN), and alkaline phosphatase, alanine
aminotransferase (ALT), and aspartate aminotransferase (AST) ≤3 X ULN (in the case of
liver metastases, ≤5 X ULN).If there are bone metastases, liver-specific alkaline
phosphatase may be separated from the total and used to assess liver function instead
of total alkaline phosphatase;

9. For patients with hypertension, it must be well controlled. If a patient presents
with poorly controlled hypertension, defined as a mean systolic blood pressure ≥140
mm Hg or mean diastolic blood pressure ≥90 mm Hg,antihypertensive medication(s)
should be initiated or adjusted with a goal to control the blood pressure <140/90 mm
Hg. Blood pressure must be reassessed on 2 occasions, consecutively, that are
separated by a minimum of 24 hours;

10. Male or female patients of child-producing potential must agree to use double barrier
contraception, oral contraceptives, or avoidance of pregnancy measures during the
study and for 90 days after the last day of treatment;

11. Females of childbearing potential must have a negative serum pregnancy test at
Screening;

12. Females may not be breastfeeding; Ability to understand and willingness to sign a
written informed consent.

Exclusion Criteria:

1. Received chemotherapy, targeted therapy, radiotherapy, surgery, immunotherapy, or
treatment in another clinical study within the 30 days prior to commencing study
treatment or have not recovered from side effects of all treatment-related toxicities
to Grade ≤1, except for peripheral neuropathy (Grade 1 and Grade 2 are permitted) and
alopecia;

2. Previously received irinotecan or irinotecan derivatives in Phase II
(irinotecan-containing regimens are allowed in Phase Ib);

3. Previously received anti-alpha 2 integrin therapy;

4. History of other malignancies except: (1) adequately treated basal or squamous cell
carcinoma of the skin; (2) curatively treated in situ carcinoma of the uterine
cervix; or (3) other curatively treated solid tumor with no evidence of disease for
≥5 years;

5. Presence of brain metastases, unless the patient has received adequate treatment at
least 4 weeks prior to randomization, and is stable, asymptomatic, and off steroids
for at least 4 weeks prior to randomization;

6. Are currently receiving any other anticancer treatment;

7. Serious non-healing wound, ulcer, or active bone fracture;

8. Major surgical procedure, open biopsy, or significant traumatic injury within 28 days
prior to Day 1, or anticipation of need for a major surgical procedure during the
course of the study;

9. Refractory nausea and vomiting, malabsorption, significant bowel resection, or any
other medical condition that would preclude adequate absorption or result in the
inability to take oral medication;

10. Significant cardiovascular impairment (history of congestive heart failure New York
Heart Association [NYHA] Grade >2, unstable angina or myocardial infarction within
the past 6 months, or serious cardiac arrhythmia);

11. Active hemoptysis (defined as bright red blood of ½ teaspoon or more) within the 30
days prior to study entry;

12. Current or recent use (within 7 days) of full-dose warfarin (except low-dose warfarin
as required to maintain patency of pre-existing, permanent indwelling IV catheters).
For patients receiving warfarin, International Normalization Ratio (INR) should be
<1.5. Patients may have prophylactic use of low molecular weight heparin; however,
therapeutic use of heparin or low molecular weight heparin is not acceptable;

13. History of bleeding diathesis or coagulopathy;

14. Any history of cerebral vascular accident, transient ischemic attack, or Grade ≥2
peripheral vascular disease, unless they have had no evidence of active disease for
at least 6 months prior to randomization;

15. Abdominal fistula, gastrointestinal perforation, or intra-abdominal abscess within 6
months prior to Day 1, unless affected area has been removed surgically;

16. Patients with organ allografts requiring immunosuppression;

17. Known positive human immunodeficiency virus (HIV), known hepatitis B surface antigen,
or active hepatitis C positive;

18. Patients with a history of allergic reactions attributed to compounds of similar
chemical or biologic composition to irinotecan, 5-FU, or leucovorin;

19. Hypersensitivity to sulfonamide derivatives;

20. Have any medical condition that would interfere with the conduct of the study.