Pemetrexed-cisplatin will be given into a vein in the arm (intravenously) every 3 weeks. The TroVax® vaccine will be given as an injection into the shoulder muscle (intramuscularly) 3 weeks before chemotherapy starts, one week before chemotherapy starts, then every 3 weeks. Each participant will receive 4 chemotherapy and 9 vaccine treatments if they complete the planned trial schedule. We aim to recruit 26 patients into the trial over a two year period. If this study shows that pemetrexed-cisplatin chemotherapy plus the TroVax® vaccine is safe and beneficial in terms of stimulating the immune system, the combination will be tested further in larger clinical trials.