Phase I/IIa Study for PM1032 in the Treatment of Patients With Advanced Solid Tumors

Inclusion Criteria:

* Voluntary participation in clinical study; fully understand the study and sign informed consent voluntarily;
* Male or female aged 18 to 75 years;
* Subjects with malignant tumor confirmed by histology or cytology, subjects with advanced malignant solid tumors who have no standard treatment, have failed standard treatment or are not eligible for standard treatment:

  1. Phase I dose escalation stage: gastric/gastroesophageal junction adenocarcinoma, esophageal cancer, etc.;
  2. Phase I dose expansion stage, phase IIa dose expansion stage: gastric/gastroesophageal junction adenocarcinoma, esophageal cancer, other tumors; CLDN18.2-positive tumor expression as determined by the CLDN18.2 IHC assay in central laboratory.
* Adequate organ function;
* ECOG score was 0-1;
* Expected survival≥12 weeks;

Exclusion Criteria:

* History of severe allergic, severe allergy to drugs or known allergy to any component of the drug in this study;
* Previous exposure to immune co-stimulatory molecule agonists such as 4-1BB mono/bispecific antibodies, etc;
* Patients who received CLDN18.2-targeted mono/bispecific antibodies or cell therapy;
* Cerebral parenchymal metastasis or meningeal metastasis with clinical symptoms were deemed unsuitable for this study by the investigator;
* Current definite interstitial lung disease or non-infectious pneumonitis, except for local radiotherapy;
* Current presence of uncontrolled pleural, pericardial, and peritoneal effusions;
* Adverse reactions to previous anti-tumor therapy have not recovered to NCI-CTCAE V5.0 rating≤1;
* Patients ever received the following treatments or drugs prior to the study treatment:

  1. Major organ surgery within 28 days prior to initiation of trial treatment or requiring elective surgery during the trial period;
  2. Received live attenuated vaccine within 28 days prior to the study treatment;
  3. Received chemotherapy, radical/extensive radiation, biotherapy, endocrine therapy and other anti-tumor drug therapy within 4 weeks of the first administration;
  4. Received systemic glucocorticoid or other immunosuppressive therapy within 2 weeks before the trial treatment;
* Active bleeding within 3 months of the first administration;
* History of allogeneic hematopoietic stem cell transplantation or allogeneic organ transplantation;
* Pregnant or lactating women;
* Other conditions considered unsuitable for this study by the investigator.