Study to Test the Safety and Tolerability of PF-07062119 in Patients With Selected Advanced or Metastatic Gastrointestinal Tumors.

Inclusion Criteria

• For Part 1 and Part 2, diagnosis of advanced/metastatic colorectal, gastric or esophageal adenocarcinoma that is resistant to standard therapy or for which no local regulatory approved standard therapy is available that would confer significant benefit.
• For Part 2, diagnosis of colorectal adenocarcinoma that is resistant to standard therapy or for which no standard therapy is available
• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) 0 or 1
• Measurable disease or non-measurable disease and refractory to or intolerant of existing therapies (Part 1)
• Measurable disease as defined by RECIST 1.1 is required (Part 2)

Exclusion Criteria

• Known active uncontrolled or symptomatic Central Nervous System (CNS) metastases
• Other active malignancy within 3 years prior to randomization, except for adequately treated basal cell or squamous cell skin cancer, or carcinoma in situ
• Major surgery or radiation within 3 weeks prior to study entry
• Last anti-cancer treatment within 4 weeks prior to study entry
• Active or history of clinically significant autoimmune disease that required systemic immunosuppressive medication
• Active or history of clinically significant gastrointestinal disease
• Participation in other studies involving investigational drug(s) within 2 weeks prior to study entry
• Pregnant or breastfeeding female patients