Inclusion Criteria:
* Age 18 years or older; able to provide written informed consent and comply with study visits and procedures.
* Pathologically confirmed, unresectable advanced solid tumor.
* Disease progression after at least one systemic therapy, with no beneficial standard option available or tolerated. Disease-specific prior therapy requirements apply to urothelial and renal cell carcinoma cohorts.
* At least one measurable lesion by RECIST version 1.1, ECOG performance status of 0 or 1, and life expectancy of at least 3 months.
* Adequate bone marrow, renal, hepatic, coagulation, and cardiac function as defined in the protocol.
* Meets protocol requirements for reproductive safety and tumor tissue availability.
Exclusion Criteria:
* Relevant hypersensitivity or intolerance to prior immunotherapy, interleukin-2 based therapy, monoclonal antibodies, or the study treatment; or prior immunotherapy discontinued because of an immune-related adverse event.
* Untreated or unstable central nervous system metastases, leptomeningeal disease, or brainstem metastases.
* Clinically significant autoimmune or skin disease requiring systemic treatment; Stevens-Johnson syndrome or toxic epidermal necrolysis; or current, suspected, or steroid-treated interstitial lung disease/pneumonitis.
* Unresolved toxicity from prior therapy, or recent anticancer treatment, major surgery, live vaccine, or other restricted therapy within protocol-defined washout periods.
* Clinically significant cardiac, thromboembolic, cerebrovascular, gastrointestinal, bleeding, or other uncontrolled medical condition.
* Active or recent severe infection.
* Prior allogeneic transplantation or adoptive cellular immunotherapy; concurrent investigational therapeutic trial; or pregnancy or breastfeeding.
* Another malignancy within 5 years, except permitted low-risk or in situ cancers; or any condition that increases risk, prevents consent or compliance, or could interfere with study interpretation.
