A First-in-Human, Open-Label, Phase 1/2 Dose-Escalation with Enrichment and Dose-Expansion Study to Investigate the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Antitumor activity of GIM-122 as a Single Agent in Adult Subjects with Advanced Solid Malignancies

Inclusion Criteria: General - Written informed consent - ECOG performance status 0-1. - Laboratory assessment 28 days prior to enrollment for assessment of acceptable cardiac, renal and hepatic functions - Recommended Double methods of contraception 90-days post treatment Cancer Specific - Histologically or cytologically confirmed locally advanced/unresectable or metastatic solid tumor - Received FDA approved treatment of PD-1 inhibitor or PD-L1 inhibitor for advance malignant tumors and have progressed/relapsed, are refractory, or intolerant - Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1 - Had prior therapy with PD-1/PD-L1 inhibitors. Other checkpoint inhibitors (ie, CTLA4, LAG3) are permitted if they did not lead to treatment discontinuation - No other lines of therapy that are available Exclusion Criteria: General - Enrolled in any other interventional clinical trial, starting within 4 weeks of the first dose of GIM-122 and throughout the duration of the study, or is receiving other therapy directed at their malignancy - Women who are pregnant or breastfeeding - History of cardiac issues, pulmonary embolism, active and clinically significant bacterial, fungal, or viral infection ≤ 6 months prior to dosing - Contraindications to the imaging assessments or other study procedures that subjects will undergo or any medical or social condition that, in the opinion of the investigator, might place a subject at an increased risk, affect compliance, or confound safety or other clinical study data interpretation Cancer Specific - Current second malignancy at other sites - Leptomeningeal disease - Spinal cord compression - Symptomatic or new or enlarging central nervous system (CNS) metastases Treatment-specific Exclusion Criteria - Ongoing toxicity > Grade 1 from prior therapy according to Common Terminology Criteria for Adverse Events (CTCAE) v 5.0 - Has undergone a major surgery < 1 month prior to administration of GIM-122 - Has received radiation therapy within 2 weeks prior to administration of GIM-122 - Has undergone or is anticipated to undergo organ transplantation including allogeneic or autologous stem cell transplantation at any time - Has received systemic anti-cancer therapy within 2 weeks and cytotoxic agents that have a major delayed toxicity within 4 weeks, of the first dose of GIM-122 - Prior treatment with other immune modulating agents within < 4 weeks prior to the first dose of GIM-122. - Has a diagnosis of immunodeficiency, either primary or acquired - Has received treatment with systemic steroids or any form of immunosuppressive therapy within 14 days prior to administration of GIM-122 - Has active or prior history of autoimmune disease, including ulcerative colitis and Crohn's disease, or any condition that requires systemic steroids. - Has a known severe intolerance to or hypersensitivity reactions to monoclonal antibodies, Fc-bearing proteins, or IV immunoglobulin preparations; prior history of human anti-human antibody response; known allergy to any of the study medications, or excipients in the various formulations of any agent. - Has received live vaccines within 30 days of study initiation (inactivated vaccines are allowed; seasonal vaccines should be up to date > 30 days prior to administration of GIM-122).