#$%^&*AU2017261455A120171130.pdf#####ABSTRACT A method for the prophylaxis and/or treatment of a tumour in a subject is provided. The method comprises the steps of administering a therapeutically effective amount of a composition comprising an anti-tumour agent and a therapeutically effective amount of a composition 5 comprising 5-[2pyrazinyl]-4-methyl-1 ,2-3-thione, or an analogue, derivative, metabolite, prodrug, solvate or pharmaceutically acceptable salt thereof to the subject. Examples of anti-tumour agents for use in the method of the invention are platinum-based agents, such as cisplatin, and monoclonal antibodies, such Cetuximab. Also provided are compositions comprising an antitumour agent and 5-[2pyrazinyl]-4-methyl-1 ,2-3-thione, or an analogue, derivative, metabolite, 10 prodrug, solvate or pharmaceutically acceptable salt thereof.