A First-in-human, Dose Escalation and Indication Expansion Study of BNT3212 as Monotherapy or in Combination With BNT327 in Adults With Advanced Solid Tumors

Key Inclusion Criteria: * Participants with histologically or cytologically confirmed locally advanced, recurrent, or metastatic solid tumors that have progressed after at least one available standard therapy; or for whom the standard therapy is considered inappropriate or intolerable. * Have at least one measurable lesion based on RECIST v1.1. * Eastern Cooperative Oncology Group performance status of 0 (fully active, able to carry out all pre-disease activities without restriction) or 1 (unable to perform physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature). * Predicted life expectancy of ≥3 months. * Left ventricular ejection fraction ≥50% by either echocardiography or multigated acquisition scan within 28 days prior to first dose of study treatment. * Adequate liver, renal, hematological, and coagulation function. * Recovery to Grade 0-1 (or baseline) from adverse reactions related to prior anti cancer therapy except for: * Asymptomatic laboratory abnormalities such as elevated alkaline phosphatase, hyperuricemia, elevated serum amylase/lipase, and elevated blood glucose. * Toxicity that the investigator determined to have no safety risk, such as alopecia, Grade 2 peripheral neurotoxicity, hypothyroidism stabilized by hormone replacement therapy, etc. * The investigator considers discontinuation of protocol-defined anti-cancer therapies and restricted medications with protocol-defined washout periods as medically acceptable. * For Parts B and D only: Participants must be diagnosed with specific indications. Key Exclusion Criteria: * Active infection (e.g., bacterial or fungal infections) requiring systemic treatment (e.g., severe pneumonia, bacteremia, sepsis), except oral antibiotics. * Participants with primary central nervous system (CNS) malignancies. * Active CNS metastases, defined as untreated and symptomatic, or requiring therapy with corticosteroids or anticonvulsants to control associated symptoms. * Unstable pleural effusion or ascites requiring thoracentesis or paracentesis within 14 days prior to initiation of study treatment. * Have active, or a history of, pneumonitis requiring treatment with steroids, or has active, or a history of, interstitial lung disease. * Clinically significant pulmonary complications. * History of severe cardiovascular disease. * Have a history of significant hematologic toxicity to prior lines of therapy, as assessed by investigator, e.g., Grade 4 febrile neutropenia or recurrent/persistent Grade 3 to 4 neutropenia. * Have active or chronic corneal disorders or with any clinically significant corneal disease that prevents adequate monitoring of drug-induced keratopathy. * Have uncontrolled hypertension while on antihypertensive medicine or poorly controlled diabetes. * Concurrent malignancy within 5 years prior to study enrollment. Exceptions: basal cell carcinoma, squamous cell carcinoma of the skin, carcinoma in situ after radical resection. * Unstable thrombotic event (e.g., deep vein thrombosis, arterial thrombosis, pulmonary embolism). * Have adverse reactions from prior anti-tumor therapy that have not returned to Grade 1 (graded by NCI CTCAE v5.0 criteria) or below (unless the investigator determines that certain AEs pose no safety risk to participants, such as hair loss, Grade 2 peripheral neuropathy or stable hypothyroidism under hormone replacement therapy) are not eligible for the study. * For Parts C and D only: Prior treatment with PD-1/L1 and VEGF-A antibody combinations (including bispecific antibodies to PD-1/L1 and VEGF-A). * For Parts C and D only: Have active, or history of, autoimmune disease with risk of exacerbation following PD-L1 inhibition OR an immune deficiency (e.g., allogeneic hematopoietic stem cell transplantation or organ transplantation). Participants with protocol-specified conditions may be eligible. * For Parts C and D only: Have serious non-healing wounds, ulcer, or bone fracture. * For Parts C and D only: Have evidence of major coagulation disorders or other significant risks of hemorrhage. * For Parts C and D only: Have a history of serious Grade 3 or higher immune-related AEs that led to treatment discontinuation of a prior immunotherapy. * For Parts C and D only: Have a history of small bowel obstruction requiring hospitalization within the past 3 months prior to the first dose of IMP. * For Parts C and D only: Have received: * anticoagulant therapy for therapeutic purposes (except low molecular weight heparin) within 14 days prior to the first dose of IMP. * antiplatelet drugs within 10 days prior to the initiation of study treatment. NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.