A First-in-human Clinical Trial to Test if the Investigational Drug BNT3219 is Safe and Potentially Beneficial for People With Advanced Solid Tumors When Given Alone or Together With Other Investigational Drugs

Key Inclusion Criteria:

• Are ≥18 years of age at the time of the informed consent form signature. Local laws will be followed if the age of consent is older.
• Have histologically or cytologically confirmed locally advanced, recurrent, or metastatic solid tumors which have progressed after at least one available standard therapy; or for whom the standard therapy is considered to be ineffective, inappropriate or intolerable, or for whom no standard treatment is available.
• Must be willing to provide a tissue sample, archival or fresh, during the screening period. An archival sample less than 2 years old is only acceptable if biopsy is not feasible due to safety concerns.
• Have at least one measurable lesion based on RECIST v1.1.
• Have an 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).
• Have a predicted life expectancy of ≥3 months.
• Have a left ventricular ejection fraction of ≥50% by either echocardiogram or multi-gated acquisition scan within 28 days prior to first dose of study treatment.
• Have an adequate liver, renal, hematological, and coagulation function as defined by the protocol.
• Have recovered to Grade 1 or baseline from adverse reactions related to prior anticancer therapy except for 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-specified anticancer therapies and restricted medications with protocol-specified washout periods prior to the first dose of study treatment as medically acceptable.

Key Exclusion Criteria:

• Have an active infection (e.g., bacterial or fungal infections or tuberculosis) requiring systemic IV treatment (e.g., severe pneumonia, bacteremia, sepsis), or any uncontrolled infection within 14 days prior to the first dose of study treatment.
• Have active central nervous system metastases and/or carcinomatous meningitis as defined in the protocol.
• Participants at imminent risk for spinal cord compression or leptomeningeal disease are not eligible.
• Have 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. Those with a history of pulmonary fibrosis or currently diagnosed with severe lung diseases such as interstitial pneumonia, pneumoconiosis, chemical pneumonitis, or any other condition resulting in significant impairment in lung function.
• Have clinically significant pulmonary complications including, but not limited to, chronic obstructive pulmonary disease, restrictive lung disease, lung injury accompanied with autoimmune disease/connective tissue disorders.
• Have a history of severe cardiovascular disease as defined in the protocol.
• Have a history of serious Grade ≥3 immune-related adverse events that led to treatment discontinuation of a prior immunotherapy. Participants with a history of Grade ≥3 that did not lead to treatment discontinuation of a prior immunotherapy may be enrolled per investigator's discretion.
• Have uncontrolled hypertension or poorly controlled diabetes as defined in the protocol within the screening period and prior to study treatment.

• Have a concurrent malignancy within 5 years prior to study enrollment except for:

  • Curatively treated basal cell or squamous cell carcinoma of the skin.
  • Curatively treated cervical cancer in-situ.
  • Curatively treated superficial or non-invasive bladder cancer.
  • Curatively treated ductal or lobular breast carcinoma in situ and not currently receiving any systemic therapy.
  • Localized prostate cancer that has been treated surgically with curative intent and presumed cured.
  • Localized papillary carcinoma of thyroid that has been treated surgically with curative intent and presumed cured.
• Have had an unstable thrombotic event (e.g., deep vein thrombosis, arterial thrombosis, pulmonary embolism) requiring therapeutic intervention within 3 months.
• Have known human immunodeficiency virus infection or known acquired immunodeficiency syndrome (exceptions apply).
• Have an active hepatitis B virus (HBV) infection (chronic or acute; defined as having a positive hepatitis B surface antigen test result at screening). However, participants with known HBV infection or resolved HBV infection (defined as the presence of hepatitis B core antibody and absence of hepatitis B surface antigen) are eligible only if they are negative for HBV deoxyribonucleic acid (DNA) (HBV viral load is below the limit of quantification per local laboratory).
• Have an active hepatitis C virus (HCV) infection. Participants with a negative HCV antibody test at screening or positive HCV antibody test followed by a negative HCV ribonucleic acid test at screening are eligible. Participants who have completed curative antiviral treatment with HCV viral load below the limit of quantification are allowed.
• Have received systemic corticosteroids, live attenuated vaccine(s) or drugs within protocol-specified requirements prior to study treatment.
• Have active tuberculosis or an active syphilis infection.

NOTE: Other protocol defined Inclusion/Exclusion criteria apply.