HDM-2012

Part I (dose escalation phase, Ia)Main objectives: To evaluate the safety and tolerability of HDM2012 at different doses in subjects with advanced solid tumors. To explore the maximum tolerated dose (MTD) of HDM2012 in subjects with advanced solid tumors and determine the recommended dose for expansion (RDE). Secondary objectives: To evaluate the pharmacokinetic (PK) characteristics of HDM2012 in subjects with advanced solid tumors. To evaluate the immunogenicity characteristics of HDM2012 in subjects with advanced solid tumors. To evaluate the preliminary anti-tumor activity of HDM2012 in subjects with advanced solid tumors. Part II (dose expansion phase, Ib)Main objectives: To evaluate the preliminary anti-tumor activity of HDM2012 at the RDE dose in specific cancer types. To evaluate the safety and tolerability of HDM2012 at the RDE dose. To determine the recommended dose (RP2D) for Phase II clinical trials of HDM2012. Secondary objectives: To evaluate the long-term efficacy of HDM2012 at the RDE dose in specific cancer types. To study the PK characteristics of HDM2012 in subjects with advanced solid tumors. To investigate the immunogenicity profile of HDM2012 in subjects with advanced solid tumors.