 - Experimental nature of the study drug. The drug stimulates the immune system to produce more proteins that will attack the tumour cells. It is thought that this will be selective for tumour cells; however it is possible that effects on normal tissues may cause side effects. These risks will be managed as much as possible by regular 3 weekly clinical assessments as a hospital outpatient, by experienced clinicians while having the study treatment. Comprehensive assessments for safety will be carried out including more intensive monitoring with blood tests. 