A Study Evaluating TAS-102 Plus Nivolumab in Patients With MSS CRC

Inclusion Criteria

• Has provided written informed consent.
• Participants with confirmed histologically proven metastatic or locally advanced colorectal adenocarcinoma who are microsatellite stable (MSS) (ie, not microsatellite instable [MSI]) based on either an analysis of tissue from a prior biopsy or based on tissue from a new biopsy.
• Participants with the presence of at least 1 lesion with measurable disease as defined by 10 millimeters (mm) in the longest diameter for a soft tissue lesions or 15 mm in the short axis for a lymph node by response evaluation criteria in solid tumors (RECIST) and immune related response-criteria (irRC) for a response assessment.
• Participants has received at least 2 prior lines of standard chemotherapies for metastatic colorectal cancer (mCRC) and is refractory to or failing those chemotherapies.
• Age greater than or equal to (>=) 18 years.
• Eastern Cooperative Oncology Group performance status of 0 to 1
• Life expectancy of >=4 months.
• Has adequate organ function.
• Women of childbearing potential must have a negative pregnancy test (urine or serum) within 7 days before starting study drugs. Is able to take medications orally.
• Is able to take medications "orally".

Exclusion Criteria

• Has a serious illness or medical condition.
• Treatment with any of the following within the specified time frame before enrollment:
• Major surgery within the past 4 weeks (the surgical incision should be fully healed before study drug administration).
• Any anticancer therapy within the past 3 weeks before enrollment.
• Extended field radiation within the past 4 weeks or limited field radiation within the past 2 weeks before enrollment.
• Any investigational drug/device received within the past 4 weeks or 5 times the half-life (whichever is shorter) before enrollment.
• Previous treatment with TAS-102.
• Prior treatment with anti-programmed cell death-1 (anti-PD-1), anti-programmed cell death ligand (anti-PD-L1), anti programmed cell death ligand 2, anti-CD137, anti-OX-40, anti CD40, anti cytotoxic T lymphocyte associated antigen-4 antibodies, or any other immune checkpoint inhibitors.
• Unresolved toxicity of >=Common Terminology Criteria for Adverse Events version (CTCAE) version 4.03 grade 2 attributed to any prior therapies (excluding anemia, alopecia, skin pigmentation, and platinum induced neurotoxicity).
• Prior events of immune-mediated pneumonitis, immune-mediated colitis, immune-mediated hepatitis, immune-mediated endocrinopathies, immune mediated nephritis and renal dysfunction, immune mediated rash, immune mediated encephalitis, and history of infusion reactions to nivolumab.
• Known or assumed hypersensitivity to TAS-102 or nivolumab or any of its ingredients, including polysorbate 80-containing infusion.
• Previous severe hypersensitivity reaction to treatment with another mAb.
• Pregnant or lactating female.
• Inappropriate for entry into this study in the judgment of the investigator.