Platform Trial Evaluating Safety and Efficacy of BI 754091 Anti- PD-1 Based Combination Therapies in PD-(L)1 naïve and PD- (L)1 Pretreated Patient Populations With Advanced/Metastatic Solid Tumours.

Inclusion Criteria

Master Protocol:

- Provision of signed and dated, written Master informed consent form (ICF) prior to any
trial-specific procedures, sampling, or analyses.

- Patient ≥18 years of age at the time of signature of the ICF.

- Eastern Cooperative Oncology Group (ECOG) score: 0 to 1.

- Patient must agree to a pre-treatment biopsy (if archival tissue is not available) and
on-treatment tumour biopsy.

- Life expectancy of at least 12 weeks after the start of the treatment according to the
Investigator's judgement.

- Male or female patients. Women of childbearing potential (WOCBP)1 and men able to
father a child must be willing and able to use highly effective methods of birth
control (that result in a low failure rate of less than 1% per year when used
consistently and correctly) during trial participation and for at least 6 months after
the last administration of trial medication.

Module A:

-Histologically confirmed diagnosis of one of the following cohorts:

- Cohort 1 GEC - Locally advanced, unresectable or metastatic gastric adenocarcinoma or
gastro oesophageal adenocarcinoma (GEC) (defined as primary tumour localisation below
the gastro oesophageal junction (GEJ) with prior anti-PD-1 or anti-PD-L1 based treated
tumour.

- Cohort 2 Patients with secondary resistance to anti-PD-1 or anti-PD-L1 based therapy:
Any advanced or metastatic solid tumour with previously anti-PD-1 or anti-PD-L1 based
treatment who progressed after achieving benefit

- Cohort 3 Patients with primary resistance to anti-PD-1 or anti-PD-L1 based therapy:
Select advanced or metastatic solid tumour types with previous anti-PD- 1/PD-L1 based
treated tumour without achieving benefit.

- All patients must have measurable lesions according to RECIST v1.1

- Patient must agree to pre- and on-treatment tumour biopsies. If archived tumour tissue
is available from the last treatment failure, sections may be supplied instead of a
pre-treatment biopsy.

Exclusion Criteria

Master Protocol:

- Any investigational treatment anti-tumour treatment within 4 weeks or within 5
half-life periods (whichever is shorter) prior to the initiation of trial treatment.

- A maximum of one anti-PD-(L)1-based treatment regimen prior to entering study

- Major surgery ('major' according to the Investigator's assessment) performed within 12
weeks prior to first trial treatment or planned within 12 months after screening,
e.g., hip replacement.

- Known history of severe hypersensitivity reactions to other mAbs or known
hypersensitivity to the trial drugs or their excipients.

- Known presence of symptomatic central nervous system (CNS) metastases, unless
asymptomatic and off corticosteroids and/or anticonvulsant therapy for at least 2
weeks prior to start of treatment.

- Immunosuppressive corticosteroid doses (>10 mg prednisone daily or equivalent) within
4 weeks prior to the first dose of study treatment.

- Active autoimmune disease or a documented history of autoimmune disease, except
vitiligo or resolved childhood asthma/atopy, or a patient removed from previous
anti-PD-1 or anti-PD-L1 therapy because of a severe immune-related adverse event
(irAE).

Module A:

- Previous treatment with an anti-LAG-3 agent

- The use of systemic steroids

- Autoimmune disease