The purpose of this study is to evaluate the safety of [68Ga]Ga-NOTA-SNA002 and investigate the uptake of [68Ga]Ga-NOTA-SNA002 in patients with solid tumors.

After being informed about the study and potential risks, all patients giving written informed consent will be evaluated to determine eligibility for study entry. Patients will receive an injection of [68Ga]Ga-NOTA-SNA002 (1.0-5.0mCi) in Day1 and will undergo PET/CT scanning to determine uptake of [68Ga]Ga-NOTA-SNA002 in tumor lesions and reference tissues.

Inclusion Criteria:

1. Age 18-75 years (including boundary values);
2. Have behavioral ability, and voluntarily participate in this clinical study, and sign the informed consent form (ICF);
3. Performance status (ECOG) score 0-2 points (see Appendix 1 for details);
4. Basal heart rate 60-100 beats/min (including boundary values);
5. Blood pressure measurement < hypertension grade 1 level (including a history of hypertension, systolic blood pressure < 140 and diastolic blood pressure < 90 mmHg by exercise or drug treatment);
6. Patients with confirmed solid tumors;
7. Patients who must have at least one image-measurable lesion according to the evaluation criteria for solid tumors (RECISTv1.1);
8. Imaging results show that at least one tumor lesion can be needle biopsy or surgical treatment to obtain specimens (enhanced CT, enhanced MRI or 18F-FluroDeoxyGlucose(FDG) PET/CT results are acceptable);
9. Patients obtained with immunohistochemical PD-L1 expression results within the previous month.

Exclusion Criteria:

1. Those who are unable to follow this clinical trial protocol well enough to make visits, or undergo relevant examinations, or treatment;
2. Those who have extremely poor nutritional status and cannot tolerate the trial;
3. Known or suspected evidence of active autoimmune disease;
4. Patients taking high doses of hormones, such as more than 20mg of hydrocortisone or 5mg of prednisone in the morning and more than 10mg of hydrocortisone or 2.5mg of prednisone at night；
5. Those with known severe allergy to SNA002, similar drugs or excipients；
6. Patients with brain metastases；
7. Serum virology tests: positive results for any of hepatitis B virus surface antigen, hepatitis C virus antibodies, syphilis-specific antibodies or those who cannot be determined to be negative for human immunodeficiency virus antibodies；
8. Women who are pregnant or breastfeeding.
9. Those who, in the opinion of the investigator, are not suitable to participate in this clinical study.