IPM-514

This is a open-label, multicenter study to assess the safety, tolerability, and preliminary efficacy of IPM514 in patients with esophageal squamous cell carcinoma. This study consists of dose escalation phase (IPM514 monotherapy) ，dose expansion phase (IPM514 combined with anti-PD-1 antibody) and the neoadjuvant therapy cohort(IPM514 combined with anti-PD-1 antibody, cisplatin and paclitaxel).The dose escalation and dose expansion stages will include patients with unresectable advanced, recurrent or metastatic ESCC who have failed first-line treatment. After confirming the preliminary safety and effectiveness in the dose escalation and dose expansion stages, a neoadjuvant therapy cohort study will be developed, and resectable ESCC subjects will be included.