This is a first-in-human (FIH), first-in-class, Phase I/IIa, open-label study designed to evaluate the safety and tolerability of EP0089 (study drug). Study drug will initially be given via intravenous (IV) infusion once every 2 weeks (Q2W), with one treatment cycle defined as 14 days. The study will enroll patients with advanced solid tumours for whom no standard therapy exists or for whom standard therapy has failed. An independent Safety Monitoring Committee (SMC) will review safety data at regular intervals to ensure participant safety and support dose escalation decisions.