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

• 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