• Understand and sign the informed consent form voluntarily.

• ≥18 years old when signing the informed consent, regardless of sex.

• Have histologically or cytologically confirmed unresectable advanced, recurrent, or metastatic solid tumors (including but not limited to small cell lung cancer, glioblastoma, urothelial carcinoma, endometrial cancer, cervical cancer, ovarian cancer, breast cancer, and liver cancer) for which standard therapy has failed or was intolerable, and currently no standard treatment is available.

‣ Radiological or histopathological evidence indicating disease progression should be documented.

⁃ Intolerance is defined as discontinuation of treatment due to adverse events during therapy.

⁃ Recurrence is based on radiological or histopathological results.

• For glioblastoma: at least one measurable intracranial tumor lesion according to the RANO 2.0 criteria. For other solid tumors: at least one measurable lesion according to RECIST v1.1 criteria. Note: Target lesions can be located in previously irradiated areas, but must be confirmed by imaging to show disease progression after radiation.

• For glioblastoma: KPS score ≥60. For other solid tumors: ECOG performance status of 0 or 1.

• Meet the following laboratory criteria (without receiving any blood products, hematopoietic growth factors, albumin, or other treatments within 14 days prior to testing, except iron supplements):

‣ Hematology: Hemoglobin (Hb) ≥100 g/L, absolute neutrophil count (ANC) ≥1.5×10\^9/L, platelet (PLT) count ≥100×10\^9/L.

⁃ Biochemistry: 1) Dose escalation phase: Serum creatinine (Cr) ≤ upper limit of normal (ULN); total bilirubin (TBIL) ≤1.25×ULN; alanine aminotransferase (ALT), aspartate aminotransferase (AST) ≤1.5×ULN (for subjects with liver metastases or hepatocellular carcinoma: ≤3×ULN). 2) Cohort expansion phase: Cr ≤1.5×ULN; TBIL ≤1.5×ULN; ALT, AST ≤2.5×ULN (for subjects with liver metastases or hepatocellular carcinoma: ≤5×ULN).

⁃ Coagulation: International normalized ratio (INR) ≤1.5×ULN; prothrombin time (PT) and activated partial thromboplastin time (APTT) ≤1.5×ULN (for participants receiving prophylactic anticoagulation, the INR and APTT should be within a safe and effective therapeutic range as judged by the investigator).

⁃ Urinalysis: Urine protein \<2+; if ≥2+, a 24-hour urine protein quantification should be performed. \<1 g/24 h can be enrolled but ≥1 g/24 h is prohibited. without quantification when urine protein ≥2+ is not allowed.

• Expected survival ≥12 weeks.

• Cohort Expansion Phase: 1) Cohort 1: Histologically or cytologically confirmed small cell lung cancer (SCLC) that has progressed or recurred after at least two lines of systemic chemotherapy (including a platinum-based regimen). Note: A new line of treatment is defined as a change in treatment due to disease progression, not due to toxicity or other reasons. Re-initiation of the same treatment regimen after initial progression is considered a new line of treatment. 2) Cohort 2: Recurrent or progressive glioblastoma confirmed by histopathology or imaging, which has progressed or recurred after at least one prior treatment with temozolomide.