A Phase I Clinical Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Clinical Activity of GSK5733584 for Injection in Subjects with Advanced Solid Tumours

This research study is being done to learn more about an investigational treatment, GSK5733584 in its treatment of patients with advanced solid tumours. GSK5733584, are a new class of drug, called antibody-drug conjugate. GSK5733584 is an antibody that binds to a target called B7-H4 which kills the cancer cells. This study will look at how the body reacts to, how the body uses the GSK5733584 and how safe this medicine is at different doses in participants with advanced solid tumours. This may benefit people with advanced solid tumours by providing them with new treatment possibilities. This is an open-label study. That means the study doctors and the participants both will be aware of the treatment given to the participants. The study consists of Phase 1a and Phase1b. In Phase 1a, the study doctors will identify a safe dose and in Phase 1b, the chosen dose will be further studied in participants with breast and ovarian cancer. Men and non-pregnant women can be included if they are aged 18 years or older and are diagnosed with advanced or solid tumours and available treatments have stopped working. Participants cannot be included if they have received any prior chemotherapy or radiation treatment and/or have a serious and unstable medical conditions related to other organs. Participants will receive the GSK5733584 infusions into a vein, until disease progression, unacceptable toxicity, death, or withdrawal. All the participants will continue to receive safety follow-up until 90 days after the last dose (Phase 1a) and they will be additionally followed up every 12 weeks after the last dose for survival status (Phase 1b). The study will be conducted in accordance with the protocol and considering international ethical guidelines.