Dose escalation study: Primary purpose: To investigate the safety and tolerability of GLS-010 in subjects with advanced solid tumors (mainly gastric cancer, esophageal cancer). Secondary purpose: 1. To characterize the pharmacokinetics(PK) profile of GLS-010; 2. To determine dose-limiting toxicity(DLT), maximum tolerated dose (MTD) and recommended Phase II dose (RP2D) for GLS-010; 3. To assess the preliminary anti tumor activity of GLS-010; 4. To assess programmed cell death-1 (PD-1) receptor occupancy. Exploratory purpose: 1. To investigate the preliminary relationship between the expression of the ligand of PD-1 (PD-L1) /PD-L2 and efficacy; 2. To characterize immunogenicity of GLS-010. Expansion study: Primary purpose: To assess the preliminary anti-tumor activity of GLS-010 in subjects with advanced solid tumors(gastric cancer, esophageal cancer); Secondary purpose: 1. To further assess the safety and tolerability of GLS-010; 2. To further assess the safety and tolerability of GLS-010 in subjects with advanced tumors. Exploratory purpose: 1. To assess PD-1 receptor occupancy of GLS-010; 2. To assess the relationship between the expression of PD-L1/PD-L2 and efficacy; 3. To further assess the immunogenicity of GLS-010.
To investigate the safety and tolerability of GLS-010 in subjects with advanced solid tumors (mainly gastric cancer, esophageal cancer).~To investigate the preliminary relationship between the expression of the ligand of PD-1 (PD-L1) and efficacy.