A First-in-human Dose-escalation and Expansion Study With the Antibody-drug Conjugate BYON3521

Inclusion Criteria:

* Patient with histologically-confirmed, locally advanced or metastatic cancer who has progressed on standard therapy or for whom no standard therapy exists:
* Part 1 (dose-escalation): solid tumours of any origin;
* Part 2 (expansion):

  * Cohort A: Non-squamous non small cell lung cancer (non-squamous NSCLC);
  * Cohort B: Gynaecological cancers: ovarian cancer, endometrial cancer, cervical cancer;
  * Cohort C: Pancreatic adenocarcinoma (PA);
  * Cohort D: Uveal melanoma (UM).
* c-MET prevalence confirmed by:
* Part 1: Tumour c-MET positive membrane staining by immunohistochemistry (IHC) and/or MET amplification by dual In Situ Hybridization (dISH) and/or known MET-mutation;
* Part 2: Tumour c-MET membrane expression by immunohistochemistry (IHC score ≥ 2+) as determined by the central laboratory on most recent available/obtained tumour material from a site not previously irradiated;
* Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1;
* Adequate organ function

Exclusion Criteria:

* Having been treated with:
* Trastuzumab duocarmazine (SYD985) at any time;
* Other anticancer therapy within 4 weeks or as defined in the protocol;
* History or presence of keratitis, glomerulonephritis, idiopathic pulmonary fibrosis, organizing pneumonia (e.g. bronchiolitis obliterans), drug-induced or idiopathic pneumonitis, or evidence of active pneumonitis on screening chest CT scan;
* History (within 6 months prior to start IMP) or presence of clinically significant cardiovascular disease such as unstable angina, congestive heart failure, myocardial infarction, uncontrolled hypertension, or cardiac arrhythmia requiring medication;
* Symptomatic brain metastases, brain metastases requiring steroids or treatment for brain metastases within 8 weeks