A Study to Find the Best Dose of BI 1387446 Alone or in Combination With Ezabenlimab (BI 754091) in Patients With Different Types of Advanced or Metastatic Cancer (Solid Tumors)

Inclusion criteria

* Histologically or cytologically confirmed diagnosis of an advanced, unresectable and/or metastatic malignant solid tumor and indication for treatment
* Patient must have exhausted established treatment options known to prolong survival for the malignant disease, or is not eligible for established treatment options.
* Medically fit and willing to undergo all mandatory trial procedures.
* At least one tumor lesion which is suitable for injection (Screening/initial administration), appropriate for the allocated treatment arm, and measurable.
* At least 1 discrete lesion, in addition to the lesion proposed for injection, which is amenable to biopsy and is not located in the brain, mediastinum or pancreas.
* Adequate organ function or bone marrow reserve
* Further inclusion criteria apply

Exclusion criteria:

* Any investigational or antitumour treatment (including antibodies targeting Programmed Cell Death-1 (PD1) - or programmed Death-Ligand 1 (PDL1)) within 4 weeks or 5 half-life periods (whichever is shorter) prior to the initial administration of BI 1387446 or BI 754091.
* Persistent toxicity from previous treatments (including Immune-related Adverse Events (irAEs)) that has not resolved to ≤ Grade 1, except for alopecia, xerostomia, and immunotherapy related endocrinopathies which may be included if clinically stable on hormone supplements or antidiabetic drugs as per Investigator judgement
* History or evidence of active, non-treatment related autoimmune disease, except for endocrinopathies which may be included if clinically stable on hormone supplements or antidiabetic drugs.
* History or evidence of pneumonitis related to prior immunotherapy
* Immunosuppressive corticosteroid doses (\>10 mg prednisone daily or equivalent) within 2 weeks prior to the first dose of BI 1387446 or BI 754091.
* The tumor at the projected injection site has a high risk for local complications, e.g. bleeding related to encasement/infiltration of major blood vessels or contact with liver capsule, compression of vital structures in case of swelling of injected lesion, in the opinion of the Investigator.
* Active infection requiring systemic therapy at the start of treatment in the trial, including active viral hepatitis infection or active tuberculosis infection.
* Cardiac insufficiency New York Heart Association (NYHA) III or IV
* Left ventricular ejection fraction \< 50% measured by echocardiography or Multigated Acquisition (MUGA) scan
* Mean resting corrected QT interval (QTc) \>470 msec
* Further exclusion criteria apply