TL-938

Primary objectives: To evaluate the tolerability of TL938 combined with trastuzumab in patients with HER2-positive advanced colorectal cancer, explore the maximum tolerated dose (MTD), and determine the recommended dose for Phase II (RP2D, cohort 1); to evaluate the efficacy of TL938 combined with trastuzumab in the treatment of HER2-positive advanced colorectal cancer. Secondary objectives: (1) To evaluate the safety of TL938 combined with trastuzumab in the treatment of patients with HER2-positive advanced colorectal cancer; (2) To evaluate the efficacy of TL938 alone in the treatment of patients with HER2-positive advanced colorectal cancer; (3) To evaluate the safety of TL938 alone in the treatment of patients with HER2-positive advanced colorectal cancer; (4) To evaluate the pharmacokinetic characteristics of TL938 alone or in combination with trastuzumab in the treatment of patients with HER2-positive advanced colorectal cancer.