Inclusion Criteria:
* The subject voluntarily participates in this study, signs the informed consent form, and has good compliance;
* Gender is not restricted; age (calculated as of the date of signing the informed consent form): 18-75 years old;
* Eastern Cooperative Oncology Group Performance Status (ECOG PS) score: 0-1; expected survival period ≥ 3 months;
* Patients with histologically or cytologically confirmed advanced malignant solid tumors, including but not limited to epithelial ovarian cancer, fallopian tube cancer, primary peritoneal cancer, breast cancer, prostate cancer, etc.;
* Advanced solid tumors that have failed standard treatment (disease progression or intolerance) or for which there is no standard treatment plan;
* For Phase Ib (dose expansion stage), except for patients receiving maintenance treatment for ovarian cancer/fallopian tube cancer/primary peritoneal cancer, other patients are required to have target lesions meeting the RECIST 1.1 criteria. For Phase Ia (dose escalation stage), measurable lesions are not required;
* Good function of major organs;
* Women of childbearing age must agree to use effective contraceptive measures during the study and within 6 months after the end of the study; serum or urine pregnancy test must be negative within 7 days before enrollment, and they must be non-lactating subjects; men must agree to use effective contraceptive measures during the study and within 6 months after the end of the study.
Exclusion Criteria:
* History of other malignant tumors within 3 years prior to the first administration of the study drug;
* Failure to recover from toxicity and/or complications of previous interventions to CTCAE ≤ Grade 1;
* Risk of bleeding;
* Arterial thrombotic events occurring within 6 months prior to the first administration;
* Suffering from ≥ Grade 2 myocardial ischemia or myocardial infarction, supraventricular or ventricular arrhythmias, and ≥ Grade 2 congestive heart failure; poorly controlled blood pressure;
* History of psychotropic substance abuse with inability to abstain, or presence of mental disorders; patients with epilepsy requiring treatment; or patients with severe mental or neurological diseases;
* Active or uncontrolled severe infections;
* Active syphilis; HIV infection or other immunodeficiency diseases; active hepatitis B or active hepatitis C;
* Complicated with moderate to severe pulmonary diseases that significantly affect respiratory function;
* Patients with active autoimmune diseases requiring systemic treatment (e.g., disease-modifying drugs, corticosteroids, or immunosuppressants);
* Receipt of systemic treatment with prednisone \> 10 mg/day or equivalent drugs, or any other form of immunosuppressive therapy within 2 weeks prior to administration;
* History of organ transplantation (except corneal transplantation), allogeneic or autologous hematopoietic stem cell transplantation;
* Poorly controlled diabetes mellitus;
* Patients with leptomeningeal (including arachnoid and pia mater) metastases;
* Known central nervous system (CNS) involvement;
* Presence of massive serous cavity (pleural, peritoneal, or pericardial) effusions requiring repeated drainage to relieve clinical symptoms, or receipt of therapeutic serous cavity effusion drainage within 2 weeks prior to treatment;
* Current intestinal obstruction;
* Known allergy to the components of the study drug;
* Receipt of anti-tumor treatments such as radiotherapy, chemotherapy, targeted therapy, or immunotherapy within 4 weeks prior to the first administration;
* Receipt of Chinese patent medicines explicitly indicated for anti-tumor use in their drug labels approved by National Medical Products Administration (NMPA) within 2 weeks prior to the first administration;
* According to the investigator's judgment, subjects with concomitant diseases that severely endanger their safety or affect the completion of the study, or those deemed unsuitable for enrollment for other reasons.
