DDR1 x VEGFR2 x CSF-1R

Main purpose: Phase I study: Evaluate the safety and tolerability of C019199 combined with sintilimab in the treatment of patients with advanced solid tumors, and determine the maximum tolerated dose (MTD) and/or phase II recommended dose (RP2D). Phase II study: Evaluate the objective response rate (ORR) [irRECIST for immune-related solid tumor efficacy evaluation criteria] and progression-free survival (PFS) of C019199 combined with sintilimab in the treatment of patients with advanced solid tumors. Secondary purpose: Phase I study: 1. Evaluate the pharmacokinetics (PK) of C019199 combined with sintilimab in patients with advanced solid tumors. 2. Evaluate the preliminary efficacy of C019199 combined with sintilimab in the treatment of patients with advanced solid tumors: objective response rate (ORR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and disease control rate (DCR). Phase II study: 1. Evaluate the safety of C019199 combined with sintilimab. 2. Evaluate the efficacy of C019199 combined with sintilimab in the treatment of patients with advanced solid tumors: duration of response (DOR), overall survival (OS), and disease control rate (DCR).