We are investigating whether giving a vaccine called TroVax® with pemetrexed-cisplatin chemotherapy is both safe and potentially beneficial in patients with mesothelioma. This vaccine has been used in combination with chemotherapy in other types of cancer and has been shown to be safe. Cancer vaccines work by stimulating the person's immune system to fight the disease, in a similar way to the immune system fighting infection. In laboratory experiments, the vaccine has been shown to stimulate an immune response to a particular protein widely found on mesothelioma cells called 5T4. In patients with mesothelioma it is hoped that the vaccine will stimulate the immune system to attack mesothelioma cells carrying the 5T4 protein.