Phase 1 Study of Single Agent GBR 1302 in Subjects With HER2 Positive Cancers

Inclusion Criteria: 1. Progressive HER2 positive solid tumours (immunohistochemistry \[IHC\] positive or equivocal) with no available standard or curative treatment. 2. Eastern Cooperative Oncology Group (ECOG) performance score of 0-2. Exclusion Criteria: 1. Active infectious disease considered by the Investigator to be incompatible with the protocol. 2. Patients not recovered from any therapy-related toxicities from previous therapies to at least CTCAE ≤ Grade 1 except in case of liver metastases or Gilbert's Syndrome or alopecia. 3. Brain metastases that are symptomatic or untreated or that require current therapy. 4. Previous treatment with immunotherapy within 8 weeks of starting study medication, chemotherapy, radiotherapy, molecular-targeted therapy, or biological therapies (including HER2 directed therapies) within 4 weeks of starting study medication, or hormone therapy within 2 weeks of starting study medication. 5. Use of any investigational drug within the past 4 weeks before start of study medication or concomitantly with this study except for investigational immune-stimulatory therapy (e.g. checkpoint-regulator targeted treatment). The minimum washout period should be 8 weeks before starting the study medication.