Inclusion Criteria:
* 1\. Participants must have the ability to understand and sign a written informed consent form for participation in this study, including all assessments and procedures specified in the protocol;
* 2\. Male or female participants aged ≥18 years;
* 3\. At least one measurable lesion as defined by RECIST v1.1 within 28 days prior to the first dose of IBI3043;
* 4\. ECOG performance status of 0-1;
* 5\. Life expectancy of at least 12 weeks at the start of treatment;
* 6\. Adequate bone marrow and organ function as confirmed during the screening period;
* 7\. Male or female participants who are either of non-reproductive potential or agree to use at least one highly effective method of contraception during the study period (starting from screening or 2 weeks prior to first dosing, whichever comes first, and continuing until 6 months after the last dose of study drug);
* 8\. Not amenable to curative surgical resection or definitive chemoradiotherapy;
* 9\. Participants with locally advanced, unresectable, or metastatic solid tumors who have failed or are intolerant to standard therapy.
Exclusion Criteria:
* 1\. Participation in any interventional clinical study other than observational (non-interventional) studies, or currently in the up period of an interventional study;
* 2\. Adverse reactions from prior anti-tumor therapies that have not resolved to Grade 0 or 1, or baseline levels, according to NCI CTCAE v6.0, prior to the first dose of study drug (exceptions include alopecia, fatigue, hyperpigmentation, or other conditions deemed without safety risk by the investigator);
* 3\. Known symptomatic central nervous system (CNS) metastases. Participants with asymptomatic CNS metastases (i.e., no neurological syndrome and metastatic lesion diameter ≤1.5 cm) or those with stable disease post-treatment as judged by the investigator may be considered under the following conditions: absence of midbrain, pons, cerebellum, meninges, medulla oblongata, or spinal cord involvement; clinically stable for at least 4 weeks prior to the first dose of study drug (stable on ≤1.5 mg/day dexamethasone or equivalent corticosteroid and baseline anticonvulsant therapy), with no clinically confirmed new or enlarging CNS lesions.
* 4\. Patients with imaging results during the screening period suggesting that the tumor surrounds important blood vessels, or there is obvious necrosis or cavity, and the investigator judges that there is a risk of bleeding;
* 5\. Tumor invasion into surrounding critical organs or structures (e.g., cardiac pericardium, mediastinal vessels, superior vena cava, trachea, esophagus, etc.) or at risk of gastrointestinal/respiratory fistula formation;
* 6\. Received major surgery (e.g., craniotomy, thoracotomy, or laparotomy, or other surgeries as determined by the investigator) within 4 weeks prior to the first dose of study drug, excluding core biopsy; or anticipated to undergo major surgery during the study period; or presence of serious non-healing wounds, trauma, ulcers, etc.
* 7\. Known hypersensitivity, allergic reaction, or intolerance to IBI3043 or its excipients.
