A Study of Napabucasin (BBI-608) in Combination With FOLFIRI in Adult Patients With Previously Treated Metastatic Colorectal Cancer

Inclusion Criteria:

1. Written, signed consent for trial participation must be obtained from the patient
appropriately in accordance with applicable ICH guidelines and local and regulatory
requirements prior to the performance of any study specific procedure.

2. Must have histologically confirmed advanced CRC that is metastatic.

3. Must have failed treatment with one regimen containing a fluoropyrimidine, oxaliplatin
with or without bevacizumab for metastatic disease. All patients must have received a
minimum of 6 weeks of the first-line regimen that included bevacizumab (if
applicable), oxaliplatin and a fluoropyrimidine in the same cycle. Treatment failure
is defined as radiologic progression during or < 6 months after the last dose of
first-line therapy.

4. FOLFIRI therapy is appropriate for the patient and is recommended by the Investigator.

5. Imaging investigations including CT/MRI of chest/abdomen/pelvis or other scans as
necessary to document all sites of disease performed within 21 days prior to
randomization. Patients with either measurable disease or non-measurable evaluable
disease are eligible.

6. Must have an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.

7. Must be ≥ 18 years of age.

8. For male or female patient of child bearing potential: Must agree to use contraception
or take measures to avoid pregnancy during the study and for 180 days for female and
male patients, of the final FOLFIRI dose. Patients who receive single agent
napabucasin without FOLFIRI must agree to use contraception or take measures to avoid
pregnancy during the study and for 30 days for female patients and 90 days for male
patients, of the final napabucasin dose.

9. Women of child bearing potential (WOCBP) must have a negative serum or urine pregnancy
test within 5 days prior to randomization. The minimum sensitivity of the pregnancy
test must be 25 IU/L or equivalent units of HCG.

10. Must have alanine transaminase (ALT) ≤ 3 × institutional upper limit of normal (ULN)
[≤ 5 × ULN in presence of liver metastases] within 14 days prior to randomization.

11. Must have hemoglobin (Hgb) ≥ 9.0 g/dL within 14 days prior to randomization. Must not
have required transfusion of red blood cells within 1 week of baseline Hgb assessment.

12. Must have total bilirubin ≤ 1.5 × institutional ULN [≤ 2.0 x ULN in presence of liver
metastases] within 14 days prior to randomization.

13. Must have creatinine ≤ 1.5 × institutional ULN or Creatinine Clearance > 50 ml/min (as
calculated by the Cockcroft-Gault equation (Chronic Kidney Disease Epidemiology
Collaboration [CKD-EPI]) within 14 days prior to randomization.

14. Must have absolute neutrophil count ≥ 1.5 x 10^9/L within 14 days prior to
randomization.

15. Must have platelet count ≥ 100 x 10^9/L within 14 days prior to randomization. Must
not have required transfusion of platelets within 1 week of baseline platelet
assessment.

16. Patient must have adequate nutritional status with Body Mass Index (BMI) > 18 kg/m^2
and body weight of > 40 kg with serum albumin > 3 g/dL.

17. Other baseline laboratory evaluations, listed in Section 6.0, must be done within 14
days prior to randomization.

18. Patient must consent to provision of, and Investigator(s) must confirm access to and
agree to submit a representative formalin fixed paraffin block of tumor tissue in
order that the specific biomarker assays may be conducted. Submission of the tissue is
to occur prior to randomization, unless approved by the Sponsor. Where local center
regulations prohibit submission of blocks of tumor tissue, two 2 mm cores of tumor
from the block and 10-30 unstained slides of whole sections of representative tumor
tissue are preferred. Where two 2 mm cores of tumor from the block are unavailable,
10-30 unstained slides of whole sections of representative tumor tissue alone are
acceptable. Where no previously resected or biopsied tumor tissue exists or is
available, on the approval of the Sponsor/designated CRO, the patient may still be
considered eligible for the study.

19. Patient must consent to provision of a sample of blood in order that the specific
correlative marker assays may be conducted.

20. Patients must be accessible for treatment and follow-up. Patients registered on this
trial must receive protocol treatment and be followed at the participating center.
This implies there must be reasonable geographical limits placed on patients being
considered for this trial. Investigators must ensure that the patients randomized on
this trial will be available for complete documentation of the treatment, response
assessment, adverse events, and follow-up.

21. Protocol treatment is to begin within 2 calendar days of patient randomization.

22. The patient is not receiving therapy in a concurrent clinical study and the patient
agrees not to participate in other interventional clinical studies during their
participation in this trial while on study treatment. Patients participating in
surveys or observational studies are eligible to participate in this study.

Exclusion Criteria:

1. Anti-cancer chemotherapy or biologic therapy if administered prior to the first
planned dose of study medication (napabucasin or FOLFIRI) within period of time
equivalent to the usual cycle length of the regimen. An exception is made for oral
fluoropyrimidines (e.g. capecitabine, S-1), where a minimum of 10 days since last dose
must be observed prior to the first planned dose of study medication. Standard dose of
bevacizumab (5 mg/kg) may be administered prior to FOLFIRI infusion, per Investigator
decision, for as long as permanent decision to include or exclude bevacizumab is made
prior to patient randomization. Radiotherapy, immunotherapy (including immunotherapy
administered for non-malignant diseaseneoplastic treatment purposes), or
investigational agents within four weeks of first planned dose of study medication,
with the exception of a single dose of radiation up to 8 Gy (equal to 800 RAD) with
palliative intent for pain control up to 14 days before randomization.

2. More than one prior chemotherapy regimen administered in the metastatic setting.

3. Major surgery within 4 weeks prior to randomization.

4. Patients with any known brain or leptomeningeal metastases are excluded, even if
treated.

5. Women who are pregnant or breastfeeding. Women should not breastfeed while taking
study treatment and for 4 weeks after the last dose of napabucasin or while undergoing
treatment with FOLFIRI and for 180 days after the last dose of FOLFIRI.

6. Gastrointestinal disorder(s) which, in the opinion of the Qualified/Principal
Investigator, would significantly impede the absorption of an oral agent (e.g.
intestinal occlusion, active Crohn's disease, ulcerative colitis, extensive gastric
and small intestine resection).

7. Unable or unwilling to swallow napabucasin capsules daily.

8. Prior treatment with napabucasin.

9. Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, clinically significant non-healing or healing wounds, symptomatic
congestive heart failure, unstable angina pectoris, clinically significant cardiac
arrhythmia, significant pulmonary disease (shortness of breath at rest or mild
exertion), uncontrolled infection or psychiatric illness/social situations that would
limit compliance with study requirements.

10. Known hypersensitivity to 5-fluorouracil/leucovorin

11. Known dihydropyrimidine dehydrogenase (DPD) deficiency

12. Known hypersensitivity to irinotecan

13. Chronic inflammatory bowel disease (Crohn's disease or ulcerative colitis)

14. Patients receiving treatment with St. John's wort or Phenytoin.

15. Patients who plan to receive yellow fever vaccine during the course of the study
treatment.

16. Abnormal glucuronidation of bilirubin, known Gilbert's syndrome

17. Patients with QTc interval > 470 milliseconds

18. For patients to be treated with a regimen containing bevacizumab:

- History of cardiac disease: congestive heart failure (CHF) > New York Heart
Association (NYHA) Class II; active coronary artery disease, myocardial
infarction within 6 months prior to study entry; unevaluated new onset angina
within 3 months or unstable angina (angina symptoms at rest) or cardiac
arrhythmias requiring anti-arrhythmic therapy (beta blockers or digoxin are
permitted).

- Current uncontrolled hypertension (systolic blood pressure [BP] > 150 mmHg or
diastolic pressure > 90 mmHg despite optimal medical management) as well as prior
history of hypertensive crisis or hypertensive encephalopathy.

- History of arterial thrombotic or embolic events (within 6 months prior to study
entry)

- Significant vascular disease (e.g., aortic aneurysm, aortic dissection,
symptomatic peripheral vascular disease)

- Evidence of bleeding diathesis or clinically significant coagulopathy

- Major surgical procedure (including open biopsy, significant traumatic injury,
etc.) within 28 days, or anticipation of the need for major surgical procedure
during the course of the study as well as minor surgical procedure (excluding
placement of a vascular access device or bone marrow biopsy) within 7 days prior
to study enrollment

- Proteinuria at screening as demonstrated by urinalysis with 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).

- History of abdominal fistula, gastrointestinal perforation, peptic ulcer, or
intra-abdominal abscess within 6 months

- Ongoing serious, non-healing wound, ulcer, or bone fracture

- Known hypersensitivity to any component of bevacizumab

- History of reversible posterior leukoencephalopathy syndrome (RPLS)

- History of hypersensitivity to Chinese hamster ovary (CHO) cells or other human
or humanized recombinant antibodies.

19. Patients with a history of other malignancies except: adequately treated non-melanoma
skin cancer, curatively treated in-situ cancer of the cervix, or other solid tumors
curatively treated with no evidence of disease for > 3 years.

20. Any active disease condition which would render the protocol treatment dangerous or
impair the ability of the patient to receive protocol therapy.

21. Any condition (e.g. psychological, geographical, etc.) that does not permit compliance
with the protocol.