The study will begin with open-label dose escalation in ZG005 monotherapy treatment to determine the Maximum tolerated dose (MTD).

The dose-expansion stage will commence after the Recommended Phase 2 Dose (RP2D) is determined during the dose-escalation stage.Single drug dose expansion was performed in different tumors, such as :Non-small cell lung cancer, small cell lung cancer, Esophageal squamous cell carcinoma, Alveolar soft part sarcoma

The dose groups of ZG005 for dose escalations are set as 0.3 mg/kg, 1mg/kg, 3mg/kg, 10mg/kg, and 20mg/kg, intravenous infusion, once every 3 weeks.

A DLT is defined as any of the following ≥ Grade 3 adverse events occurring from the first dose to the end of first Cycle (21 days), unless the investigator deems that the AE is clearly related to the disease progress or definitely due to an external cause.

Number of participants with adverse events that are related to treatment

Objective response rate was based on response evaluation criteria in solid tumors 1.1 (RECIST 1.1)

During the dose escalation stage, if 2 of up to 6 subjects in the first dose groups experienced DLT, then the dose level will be considered to be an intolerable dose or DLT dose level, and the previous lower dose will be considered to be the MTD.