In Part I (Dose Escalation - DE), the intention is to include patients with any of the four solid tumor types: Non-Small Cell Lung Cancer (NSCLC), Pancreatic Ductal Adenocarcinoma (PDAC), Triple Negative Breast Cancer (TNBC) or Colorectal Cancer (CRC). In this part of the study safety and tolerability will be documented and the MTD/ RP2D will be determined. Patients will stay on CAN04 treatment until disease progression, unacceptable toxicity, or discontinuation for any other reason.