Inclusion Criteria:

        Subjects must meet all of the following criteria to be eligible for the study:

          -  Pathologically-confirmed, locally advanced or metastatic solid tumors that have
             relapsed or are refractory to or are not considered medically suitable to receive
             standard of care treatment (Dose Escalation Phase)

          -  Histologically-diagnosed, advanced Gl tumors, such as colorectal adenocarcinoma,
             gastric adenocarcinoma, pancreatic adenocarcinoma, bile duct carcinoma,
             hepatocellular carcinoma, esophageal carcinoma that have relapsed or are refractory
             to or are not considered medically suitable to receive standard of care treatment
             (Dose Expansion Phase)

          -  Eastern Cooperative Oncology Group score of 0 - 2

          -  Minimum life expectancy of 3 months

          -  Age 18 years or older

          -  Adequate organ function

          -  Recovery from prior treatment-related toxicities

          -  Ability to swallow tablets

          -  Willingness for patients of reproductive potential to use adequate methods of
             contraception during and for 3 months after study treatment

        Exclusion Criteria:

          -  Prior exposure to a WNT inhibitor

          -  Received previous therapy for malignancy within 21 days

          -  Major surgery within 4 weeks of first dose of study drug

          -  Radiotherapy within 2 weeks of first dose of study drug

          -  Bleeding disorder

          -  Bone abnormalities

          -  Uncontrolled central nervous system metastases or leptomeningeal metastases

          -  Requirement for immunosuppressive agents (must be off for at least 7 days)

          -  Currently receiving medications known to be inhibitors of CYP3A4/5. Subjects
             currently receiving medications of known inducers of CYP3A4/5 or substrates of
             CYP2C8/9 and CYP1A2 may be excluded.

          -  Cardiac abnormalities

          -  Known human immunodeficiency virus positive, or active hepatitis A, B or C

          -  History of additional prior malignancy with the exception of surgically cured
             carcinomas such as skin, prostate, bladder, thyroid, cervix or other carcinomas in
             situ

          -  Active systemic infection requiring intravenous antibiotics within 2 weeks of
             treatment start

          -  GI impairment that may compromise absorption of study drug

          -  Pregnancy or lactation