Inclusion Criteria:

          -  Age ≥18 years.

          -  Ability to understand and willingness to sign a written informed consent document.

          -  Phase I: Must have received all curative treatment options and at least 2 lines of
             systemic therapy.

          -  Phase II: Must have received at least 2 lines of systemic therapy including a
             fluropyrimidine, oxaliplatin, and irinotecan-containing regimen. KRAS/NRAS/BRAF
             wildtype patients must have received or refused anti-EGR.

          -  Must have received all curative treatment options and at least 2 lines of systemic and
             standard therapy.

          -  Must have measurable disease based on RECIST 1.1

          -  Must have biopsiable disease.

          -  ECOG performance status 0 or 1

          -  Life expectancy of greater than 3 months.

          -  Patients must have adequate organ and marrow function defined by study-specified
             laboratory tests within 21 days of initial study drug.

          -  Men must use acceptable form of birth control while on study.

          -  Woman of childbearing potential must have a negative pregnancy test and follow
             contraceptive guidelines as defined per protocol.

        Exclusion Criteria:

          -  Prior treatment with immunotherapy agents (including, anti-PD-1, anti-PD-L1, anti-
             PD-L2, anti-CTLA4, etc.).

          -  Prior therapy with a PI3K inhibitor

          -  Chemotherapy, target small molecule therapy, investigational therapy, or surgery
             within 4 weeks prior to first dose of treatment.

          -  Has received prior radiotherapy within 2 weeks prior to the start of treatment.

          -  Patient who is receiving or have received any other investigational agents within 4
             weeks prior to the first dose of treatment.

          -  Has received a live vaccine 30 days prior to the first dose of study drug.

          -  Has known additional malignancy that is progressing or requires active treatment..

          -  Has known central nervous system (CNS) metastases and/or carcinomatous meningitis.

          -  Has symptomatic ascites or has required a paracentesis in the last 12 weeks.

          -  Hypersensitivity reaction to study drug.

          -  Patients diagnosed of immunodeficiency or are on any immunosuppressive agents within 7
             days prior to first dose of study drug.

          -  Has active autoimmune disease that has required systemic treatment in the past 12
             months, or a documented history of clinically severe autoimmune disease, or a syndrome
             that requires systemic steroids or immunosuppressive agents.

          -  Has a history of (non-infectious) pneumonitis that required steroids or has current
             pneumonitis.

          -  Has an active infection requiring systemic therapy.

          -  Infection with HIV or hepatitis B or C.

          -  CMV PCR (cytomegalovirus polymerase chain reaction) positive.

          -  Known history or concurrent interstitial lung disease.

          -  Type I diabetes or Type II diabetes requiring treatment with a sulfonylurea,
             meglitinide, or insulin at screening.

          -  Uncontrolled cardiovascular disease.

          -  Patient with uncontrolled intercurrent illness including, but not limited to,
             uncontrolled infection, symptomatic congestive heart failure, unstable angina
             pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would
             limit compliance with study requirements.

          -  Use of anti-arrhythmic therapy (beta blockers or digoxin are permitted).

          -  Use of CYP3A4 inhibitors and inducers within 2 weeks of starting study drug and
             throughout treatment.

          -  Any arterial or venous thrombotic or embolic events within 3 months of start of study
             drug.

          -  Non-healing wound, ulcer, or fracture.

          -  Patients with evidence or history of bleeding condition.

          -  Had a blood or platelet transfusion within 7 days of Cycle 1 Day 1 treatment.

          -  Seizure disorder requiring anti-seizure medication.

          -  Conditions, including alcohol or drug dependence, intercurrent illness, or lack of
             sufficient peripheral venous access, that would affect the patient's ability to comply
             with study visits and procedures.

          -  Are pregnant or breastfeeding.

          -  Unwilling or unable to follow the study schedule for any reason.