Inclusion Criteria:

          -  Histologically or cytologically confirmed solid tumor that is metastatic (Stage IV) or
             unresectable and for whom there is no available standard therapy likely to confer
             clinical benefit, or patient who is not a candidate for such available therapy. If
             there is no contraindication, patients should have exhausted all standard of care
             (SoC) therapies before entering the trial.

          -  Measurable or evaluable disease per RECIST1.1.

          -  Male and female aged ≥ 18 years.

          -  Prior to any trial-related assessments or procedures, must sign an informed consent
             form (ICF) indicating that he or she understands the purpose and procedures required
             for the trial and are willing to participate in the trial.

          -  Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1.

          -  Adequate coagulation function at screening as determined by:

               1. International normalized ratio (INR) or prothrombin time ≤ 1.5 × upper limit
                  normal (ULN); unless on therapeutic anticoagulants with values within therapeutic
                  window),

               2. Activated partial thromboplastin time (aPTT) ≤ 1.5 × ULN (unless on therapeutic
                  anticoagulants with values within therapeutic window).

          -  Adequate hematologic function at screening as determined by:

               1. White blood cell count (WBC) ≥ 3 × 10^9/L

               2. Absolute neutrophil count ≥ 1.5 × 10^9/L (patient may not use granulocyte-colony
                  stimulating factor (G-CSF) or granulocyte-macrophage colony stimulating factor
                  (GM-CSF) to achieve these WBC and absolute neutrophil count levels)

               3. Platelet count ≥ 100 × 10^9/L

               4. Hemoglobin (Hgb) ≥ 9.0 g/dL (may not transfuse or use erythropoietin to obtain
                  this Hgb level in the past 7 days).

          -  Adequate hepatic function at screening as determined by:

               1. Total bilirubin ≤ 1.5 mg/dL (or ≤ 2.0 mg/dL for patients with known Gilbert's
                  syndrome or liver metastasis)

               2. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 × ULN;
                  ≤ 3 × ULN for patients with liver metastasis.

          -  Adequate renal function at screening as determined by: Glomerular filtration rate ≥ 45
             mL/min/1.73 m^2 - according to the abbreviated Modification of Diet in Renal Disease
             (MDRD) equation: Glomerular filtration rate = 186 × (Screatinin-1.154) × (age-0.203)
             (where Screatinin, the serum creatinine level, is expressed in mg/dL; multiply it by
             0.742 if the patient is female; multiply it by 1.212, if the patient is
             African-American [Levey et al. 1999]).

          -  Able and willing to comply with scheduled visits, treatment schedule, laboratory
             tests, lifestyle restrictions, and other requirements of the trial.

          -  Women of childbearing potential (WOCBP) must have a negative serum (beta-human
             chorionic gonadotropin [beta-hCG]) test/value at screening. Patients who are
             post-menopausal or permanently sterilized can be considered as not having reproductive
             potential.

          -  WOCBP must agree to use highly effective contraception during the trial and for 6
             months after receiving the last dose of BNT152 or BNT153. Birth control methods are
             considered highly effective if they have a failure rate of less than 1% per year, when
             used consistently and correctly.

          -  WOCBP must agree not to donate eggs (ova, oocytes) for the purposes of assisted
             reproduction during the entire trial, until 6 months after last BNT152 or BNT153
             treatment.

          -  A man who is sexually active with a WOCBP and has not had a vasectomy must agree to
             use a barrier method of birth control, e.g., either condom with spermicidal
             foam/gel/film/cream/suppository or partner with occlusive cap (diaphragm or
             cervical/vault caps) with spermicidal foam/gel/film/cream/suppository, and all men
             must also agree to not donate sperm during the trial and for 6 months after receiving
             the last dose of BNT152 or BNT153.

        Exclusion Criteria:

        Prior and concomitant therapy:

          -  Use of any investigational medical product or device within 28 days before
             administration of first dose of trial treatment.

          -  Has been receiving: radiotherapy, chemotherapy, or molecularly-targeted agents or
             tyrosine kinase inhibitors within 2 weeks or 5 half-lives (whichever is longer) of the
             start of trial treatment; immunotherapy/monoclonal antibodies within 3 weeks of the
             start of trial treatment; nitrosourea, antibody-drug conjugates, or radioactive
             isotopes within 6 weeks of the start of trial treatment.

          -  Ongoing participation in the active treatment phase of an interventional clinical
             trial.

          -  Receives concurrent systemic (oral or IV) steroid therapy >10 mg prednisone daily or
             its equivalent for an underlying condition.

          -  Has had major surgery within the 4 weeks before the first dose of trial treatment.

          -  Ongoing or active infection requiring IV treatment with anti-infective therapy that
             has been administered less than 2 weeks prior to the first dose of trial treatment.

          -  Has side effects of any prior therapy or procedures for any medical condition not
             recovered to NCI CTCAE v.5 Grade ≤ 1. Note: peripheral neuropathy Grade ≤ 2 is
             allowed; alopecia of any grade is allowed.

        Medical conditions:

          -  Current evidence of new or growing brain or leptomeningeal metastases during
             screening. Patients with known brain metastases may be eligible if they:

               1. had radiotherapy, surgery or stereotactic surgery for the brain metastases,

               2. have no neurological symptoms (excluding Grade ≤ 2 neuropathy),

               3. have stable brain metastasis on the computerized tomography (CT) or magnetic
                  resonance imaging (MRI) scan within 4 weeks before signing the informed consent,

               4. are not undergoing acute corticosteroid therapy or steroid taper. Notes: Patients
                  with central nervous system (CNS) symptoms should undergo a CT-scan or MRI of the
                  brain to exclude new or progressive brain metastases. Spinal bone metastases are
                  allowed, unless imminent fracture with cord compression is anticipated.

          -  Has a history of a cerebrovascular accident or had a transient ischemic attack less
             than 6 months before signing the ICF.

          -  Effusions (pleural, pericardial, or ascites) requiring drainage.

          -  Fever ≥ 38°C within 3 days before signing the ICF.

          -  Active autoimmune disease including but not limited to inflammatory bowel disease,
             systemic lupus erythematosus, ankylosing spondylitis, scleroderma, or multiple
             sclerosis (except type 1 diabetes with well-regulated blood sugar).

          -  Has any active immunologic disorder or after organ transplantation requiring
             immunosuppression with steroids or other immunosuppressive agents (e.g., azathioprine,
             cyclosporine A) with the exception of patients with isolated vitiligo, resolved
             childhood asthma or atopic dermatitis, controlled hypoadrenalism or hypopituitarism,
             and patients with a history of Graves' disease with stable thyroid function. Patients
             with controlled hyperthyroidism must be negative for thyroglobulin, thyroid peroxidase
             antibodies, and thyroid stimulating immunoglobulin prior to administration of trial
             treatment.

          -  Known history of seropositivity for human immunodeficiency virus (HIV) with CD4+
             T˗cell (CD4+) counts <350 cells/µL and with a history of acquired immunodeficiency
             syndrome (AIDS)-defining opportunistic infections.

          -  Known history/positive serology for hepatitis B requiring active antiviral therapy
             (unless immune due to vaccination or resolved natural infection or unless passive
             immunization due to immunoglobulin therapy). Patients with positive serology must have
             hepatitis B virus viral load below the limit of quantification.

          -  Active hepatitis C virus infection; patients who have completed curative antiviral
             treatment with hepatitis C virus viral load below the limit of quantification are
             allowed.

          -  Known hypersensitivity to a component of any trial treatment.

          -  Another primary malignancy that has not been in remission for at least 2 years, with
             the exception of those with a negligible risk of metastasis or death (including but
             not limited to adequately treated carcinoma in situ of the cervix, basal or squamous
             cell skin cancer, localized prostate cancer, or ductal carcinoma in situ). In case of
             uncertainties, the medical monitor should be consulted.

        Other comorbidities:

          -  Abnormal electrocardiograms (ECGs) that are clinically significant, such as
             Fridericia-corrected QT prolongation >480 ms.

          -  In the opinion of the treating investigator, has any concurrent conditions that could
             pose an undue medical hazard or interfere with the interpretation of the trial
             results; these conditions include, but are not limited to:

               1. Ongoing or active infection requiring antibiotic/antiviral/antifungal therapy.

               2. Concurrent congestive heart failure (New York Heart Association [NYHA] Functional
                  Classification Class III or IV).

               3. Concurrent unstable angina.

               4. Concurrent cardiac arrhythmia requiring treatment (excluding asymptomatic atrial
                  fibrillation).

               5. Acute coronary syndrome within the previous 6 months.

               6. Symptomatic pulmonary embolism within the previous 3 months.

               7. Significant pulmonary disease (shortness of breath at rest or on mild exertion)
                  for example due concurrent severe obstructive pulmonary disease.

          -  Cognitive, psychological or psychosocial impediment that would impair the ability of
             the patient to receive therapy according to the protocol or adversely affect the
             ability of the patient to comply with the informed consent process, protocol, or
             protocol-required visits and procedures.

          -  Is pregnant or breastfeeding.

          -  Patients unable to consent.