BA-1106

Primary objective: To evaluate the safety and tolerability of BA1106 injection, observe dose-limiting toxicity (DLT), and determine the maximum tolerated dose (MTD). Secondary objective: To evaluate the pharmacokinetic (PK) characteristics, immunogenicity, and preliminary efficacy of BA1106 in patients with advanced solid tumors. Exploratory objectives: (1) To analyze the changes in peripheral blood and/or intratumoral lymphocyte subset counts (including regulatory T cells Treg, effector T cells Teff), Teff/Treg, and their correlation with safety/efficacy at each time point after administration compared with baseline; (2) To analyze the changes in peripheral blood cytokines compared with baseline at each time point after administration, and their correlation with safety/efficacy.